JP7126166B2 - Wireless communication system, wireless communication method and wireless communication device - Google Patents

Description

The present invention relates to a radio communication system, a radio communication method and a radio communication device.

Among antennas that re-radiate radio waves in the direction of arrival of radio waves, the one with the simplest structure is the Van Atta array (Patent Document 1). FIG. 19 shows a four-element Van Atta array. In the Van-Atta array, a plurality of antenna elements are arranged at regular intervals, and the antenna elements located symmetrically about the center of the array are connected to each other by wires having equal path lengths. When a plane wave incident on the Van Atta array is received in the order of antenna elements #4, #3, #2, and #1, antenna elements #1, #2, #3, and # 4 are re-radiated in order. At this time, the re-radiated waves reinforce each other in phase with respect to the arrival direction of the plane wave. Although FIG. 19 shows an example of a linear array, a planar array can also be realized in the same manner.

Van-Atta arrays do not require signal processing for beamforming in the direction of arrival of radio waves, unlike phased arrays. As a result, beam formation in the direction of arrival of radio waves can be performed automatically and instantaneously, and the time from reception of radio waves to formation of beams in the direction of arrival is overwhelming compared to that of phased arrays. short to
Also, the Van-Atta array does not require a signal processor or phase shifter like a phased array. Therefore, the structure of the array can be greatly simplified, and the size and cost of the array can be reduced. Moreover, since the signal processing and the phase shifter as described above are not required, the power required for them can be reduced, and power saving can be realized.

Wireless communication using a van-atta array is also under consideration. (Non-Patent Document 1) introduces a technique in which an amplifier is added to the connection of a Van Atta array to modulate the amplitude of an incoming wave, and a technique in which an oscillator and a mixer are added to perform frequency modulation or phase modulation. In addition, (Non-Patent Document 2) introduces modulation by adding a switch to the connection of the Van Atta array. 20, 21 and 22 each show the addition of amplifiers, oscillators and mixers, and switches to the wiring of the Van Atta array. These van Atta arrays can modulate the radio waves they receive and re-radiate them in their direction of arrival, which means they can transmit information.

U.S. Pat. No. 2,908,002

Vincent Fusco, and Neil Buchanan “Developments in retrodirective array technology” IET Microwaves, Antennas & Propagation, 2013, Vol. 7, Iss. 2, pp. 131-140 P. Chan, and V. Fusco “Bi-static 5.8 GHz RFID range enhancement using retrodirective techniques” Proceedings of the 41th Microwave Conference, 2011, pp. 976-979

However, Van Atta arrays such as Non-Patent Document 1 and Non-Patent Document 2 are supposed to receive only an unmodulated continuous wave, modulate it and re-radiate it in the direction of arrival. That is, it assumes one-way communication in which the Van Atta Array can transmit information but cannot receive information. Therefore, RFID (radio frequency identifier) etc. can be considered as a main usage scene.

If the Van Atta Array can be applied to ordinary wireless communication devices such as wireless LAN access points and smartphones, it will be possible to form beams at higher speeds, reduce size and cost, and save power compared to conventional devices. becomes possible. However, the van-atta arrays capable of only one-way communication, such as Non-Patent Document 1 and Non-Patent Document 2, are insufficient for application to normal wireless communication devices, and are particularly capable of two-way communication. is considered to be an essential requirement.

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a technology that enables two-way communication using a van-atta array.

One aspect of the present invention includes a data transmission unit that transmits a data signal that is a modulated radio wave, and an unmodulated continuous wave that is an unmodulated radio wave having a frequency different from that of the data signal. I first wireless devices (I is an integer equal to or greater than 1) comprising a wave transmitting unit and a receiving unit for receiving radio waves; and J van-atters receiving the data signal and the unmodulated continuous wave. a second radio device (J is an integer of 1 or more) that is an array, the data signal of frequency f1_i (i is an integer of 1 or more) is the i-th data signal, and the unmodulated continuous wave of frequency f2_i is the i-th data signal; As the i-th unmodulated continuous wave, the second wireless device includes an i-th modulated signal filter that transmits the i-th data signal, an i-th unmodulated wave filter that transmits the i-th unmodulated continuous wave, and the i-th an i-th modulated signal demodulator that demodulates the i-th data signal that has passed through the modulated signal filter; and an i-th non-modulated wave modulator that modulates the i-th non-modulated continuous wave that has passed through the i-th non-modulated wave filter. , wherein the second radio device radiates the i-th unmodulated continuous wave after being modulated by the i-th unmodulated wave modulation unit, and the first radio device is modulated by the second radio device is a wireless communication system that receives the i-th unmodulated continuous wave after being modulated.

One aspect of the present invention is the above wireless communication system, wherein the second wireless device includes first to (2×N) antenna elements for receiving the data signal and the unmodulated continuous wave. Equipped with 2×N antenna elements (N is an integer equal to or greater than 1), the second radio device receives the i-th unmodulated continuous wave received by the n-th antenna element as the i-th unmodulated wave filter. An i-th non-modulated wave filter for an n-th antenna element to be transmitted is provided, and the second radio device, as the i-th non-modulated wave modulator, transmits the i-th non-modulated continuous wave transmitted through the n-th non-modulated wave filter. The i-th non-modulated wave modulation unit for the n-th antenna element for modulating a wave is provided, the 2×N antenna elements are arranged in an array, and the m-th antenna element (m is 1 or more (2×N) The following odd number) and the (m+1)-th antenna element are antenna elements located at symmetrical positions about the center of the array, and the i-th unmodulated continuous wave received by the m-th antenna element is the m-th After passing through the continuous wave filter CF-i, it is modulated by the m-th modulation unit Hi, modulated by the m-th modulation unit Hi, radiated from the (m+1)th antenna element, and the (m+1)th ) the i-th unmodulated continuous wave received by the antenna element is modulated by the (m+1)-th modulation unit Hi after passing through the (m+1)-th continuous wave filter CF-i, and the (m+1)-th modulation It is radiated from the m-th antenna element after being modulated by part Hi.

One aspect of the present invention is the above wireless communication system, wherein the second wireless device includes first to (2×N) antenna elements for receiving the data signal and the unmodulated continuous wave. 2×N antenna elements (N is an integer of 1 or more), and the second radio apparatus includes the n-th antenna element (n is 1 or more (2×N) or less) as the i-th modulation signal filter. an i-th data signal filter for the n-th antenna element that transmits the i-th data signal received by the integer), and the i-th modulated signal demodulator transmits the i-th modulated signal filter for the n-th antenna element. demodulate the i-th data signal.

One aspect of the present invention is the above wireless communication system, wherein the distance between the m-th antenna element and the (m+1)-th antenna element is the unmodulated continuous wave in the space in which the unmodulated continuous wave propagates. is less than the wavelength of

One aspect of the present invention is the above wireless communication system, wherein the period during which the i-th unmodulated wave modulation unit for the n-th antenna element modulates the i-th unmodulated continuous wave is the n-th modulation period, and all are the same for the n-th modulation period.

One aspect of the present invention is a radio communication method performed by the above radio communication system, wherein I first radio devices provided in the radio communication system transmit data signals, which are modulated radio waves, and non-modulated radio waves. a transmitting step of transmitting an unmodulated continuous wave that is a radio wave; a first receiving step of receiving the data signal and the unmodulated continuous wave by a second radio device included in the radio communication system; and the second radio device. a separation step of separating the data signal and the unmodulated continuous wave; a demodulation step of the second radio device demodulating the data signal; and a modulation step of the second radio device modulating the unmodulated continuous wave. a radiating step in which the second radio device radiates the unmodulated continuous wave modulated in the modulating step; and a radiating step in which the first radio device receives the unmodulated continuous wave radiated in the radiating step. and a second receiving step for performing wireless communication.

One aspect of the present invention is a van-atta array, in which a data signal of frequency f1_i (i is an integer equal to or greater than 1) is the i-th data signal, and an unmodulated continuous wave of frequency f2_i is the i-th unmodulated continuous wave , the i-th modulated signal filter that transmits the i-th data signal, the i-th non-modulated wave filter that transmits the i-th non-modulated continuous wave, and the i-th data signal that has passed through the i-th modulated signal filter The wireless device includes an i-th modulated signal demodulator for demodulation and an i-th non-modulated wave modulator for modulating the i-th non-modulated continuous wave transmitted through the i-th non-modulated wave filter.

The present invention enables two-way communication using a van-atta array.

1 is a diagram showing an example of a system configuration of a radio communication system 1 according to the first embodiment; FIG. 1 is a first diagram showing an example of frequency spectra of a data signal Di and an unmodulated continuous wave Ci according to the first embodiment; FIG. FIG. 2 is a second diagram showing an example of frequency spectra of a data signal Di and an unmodulated continuous wave Ci in the first embodiment; 4 is a diagram showing an example of the functional configuration of a second radio device 20 according to the first embodiment; FIG. FIG. 4 is a diagram showing an example of a transmission spectrum of a data signal filter 203 and a transmission spectrum of a continuous wave filter 204 in the first embodiment; FIG. 4 is a diagram showing an example of temporal change in intensity of an unmodulated continuous wave Ci and temporal change in intensity of an unmodulated continuous wave C1-i in the first embodiment; FIG. 4 is a diagram showing an example of a first modulated signal V1-i and a second modulated signal V2-i when the phase difference between the first modulated signal V1-i and the second modulated signal V2-i is 2πL/λ<2π; FIG. 3 is a diagram showing an example of a first modulated signal V1-i and a second modulated signal V2-i when the phase difference between the first modulated signal V1-i and the second modulated signal V2-i is 2πL/λ≧2π; The figure which shows an example of the frequency spectrum of the output wave in 1st Embodiment. The figure which shows an example of a functional structure of the 2nd radio|wireless apparatus 20a in 1st Embodiment. 4 is a flowchart showing an example of the flow of processing in the wireless communication system 1 of the first embodiment; The figure which shows an example of the system configuration|structure of the radio|wireless communications system 1b of 2nd Embodiment. The figure which shows an example of functional structure of 2nd radio|wireless apparatus 20b-i in 2nd Embodiment. FIG. 10 is a diagram showing an example of the functional configuration of a second radio device 20b-i when J=1 in the second embodiment; FIG. 10 is a diagram showing an example of the frequency spectrum of output waves emitted by a second radio device 20b-i according to the second embodiment; 10 is a flow chart showing an example of the flow of processing in the wireless communication system 1b of the second embodiment; The figure which shows an example of the system configuration|structure of the radio|wireless communications system 1c of 3rd Embodiment. FIG. 11 is a flowchart showing an example of the flow of processing in the wireless communication system 1c of the third embodiment; FIG. FIG. 4 is a diagram for explaining a conventional four-element Van Atta array; FIG. 1 is a first diagram for explaining a conventional antenna in which an amplifier, an oscillator, a mixer, and a switch are added to connections of a Van Atta array; FIG. 2 is a second diagram illustrating a conventional antenna in which an amplifier, an oscillator, a mixer, and a switch are added to the connections of the Van Atta array; Fig. 3 is a third diagram for explaining a conventional antenna in which an amplifier, an oscillator, a mixer, and a switch are added to the connections of the Van Atta array;

(First embodiment)
FIG. 1 is a diagram showing an example of a system configuration of a wireless communication system 1 according to the first embodiment. The wireless communication system 1 includes first wireless devices 10 - 1 to 10 -I (I is an integer of 2 or more) and a second wireless device 20 .

The first wireless device 10-i (i is an integer of 1 or more and I or less) includes a CPU (Central Processing Unit), a memory, an auxiliary storage device, etc. connected via a bus, and functions as a device by executing a program. . The first wireless device 10-i functions as a device comprising a data transmitter 101-i, an unmodulated wave transmitter 102-i, and a receiver 103-i by executing a program.

Data transmitter 101 - i transmits data signal Di to second radio apparatus 20 . The data signal Di is a radio wave modulated with a frequency f1_i and indicating predetermined information.
Unmodulated wave transmitting section 102 - i transmits unmodulated continuous wave Ci to second radio apparatus 20 . The unmodulated continuous wave Ci is an unmodulated radio wave of frequency f2_i and is a continuous wave.
The receiving unit 103-i receives radio waves.

The frequencies of all data signals Di and all unmodulated continuous waves Ci are different frequencies. Hereinafter, data signals Di are referred to as data signals D when not distinguished from each other. Hereinafter, the unmodulated continuous wave Ci will be referred to as an unmodulated continuous wave C when not distinguished from each other.

FIG. 2 is a first diagram showing an example of frequency spectra of data signal Di and unmodulated continuous wave Ci in the first embodiment.
FIG. 2 shows the frequency spectrum W_i_1 of the data signal Di and the frequency spectrum W_i_2 of the unmodulated continuous wave Ci. Data signal Di is a modulated signal and unmodulated continuous wave Ci is an unmodulated signal. Therefore, the half width of the frequency spectrum W_i_1 of the data signal Di is wider than the half width of the frequency spectrum W_i_2 of the unmodulated continuous wave Ci. The frequency spectrum W_i_1 of the data signal Di and the frequency spectrum W_i_2 of the unmodulated continuous wave Ci do not overlap on the frequency axis.

FIG. 3 is a second diagram showing an example of frequency spectra of the data signal Di and the unmodulated continuous wave Ci in the first embodiment.
FIG. 3 shows that the frequency of the data signal D and the frequency of the unmodulated continuous wave C are all different.

Returning to the description of FIG.
The second radio device 20 receives the data signal Di and the unmodulated continuous wave Ci and outputs an output wave. The output wave is a radio wave obtained by modulating the unmodulated continuous wave Ci received by the second radio device 20 by the second radio device 20 .

FIG. 4 is a diagram showing an example of the functional configuration of the second radio device 20 according to the first embodiment.
The second wireless device 20 includes a CPU (Central Processing Unit), a memory, an auxiliary storage device, and the like connected via a bus, and executes programs. By executing a program, the second radio device 20 is configured to have a first antenna element 201-1, a second antenna element 201-2, a first circulator 202-1, a second circulator 202-2, a filter unit 21, demodulation unit 22. The filter unit 21 includes first data signal filters 203-1-1 to 203-1-I, second data signal filters 203-2-1 to 203-2-I, and a first continuous wave filter 204-1- 1 to 204-1-I, second continuous wave filters 204-2-1 to 204-2-I, first modulating sections 205-1-1 to 205-1-I, and second modulating section 205- 2-1 to 205-2-I. Demodulation unit 22 includes demodulators 206-1 to 206-I.

First antenna element 201-1 and second antenna element 201-2 receive data signal Di and unmodulated continuous wave Ci. The first antenna element 201-1 and the second antenna element 201-2 transmit output waves.

The first circulator 202-1 and the second circulator 202-2 are electronic component circulators. The first circulator 202-1 and the second circulator 202-2 have three or more ports including a first port, a second port and a third port. The first port, the second port, and the third port are connected to different destinations.

Specifically, the first terminal of first circulator 202-1 is connected to first antenna element 201-1. The second terminal of first circulator 202-1 is coupled to first continuous wave filters 204-1-1 through 204-1-I and first data signal filters 203-1-1 through 203-1-I. A third terminal of the first circulator 202-1 is connected to the second modulation sections 205-2-1 to 205-2-I.

A first terminal of the second circulator 202-2 is connected to the second antenna element 201-2. A second terminal of the second circulator 202-2 is coupled to second continuous wave filters 204-2-1 through 204-2-I and second data signal filters 203-2-1 through 203-2-I. A third terminal of the second circulator 202-2 is connected to the first modulating sections 205-1-1 to 205-1-I.

The first data signal filter 203-1-i and the second data signal filter 203-2-i transmit the data signal Di, and filter the data signal D other than the data signal Di and the unmodulated continuous wave C. Don't let it pass through. First data signal filter 203-1-i is coupled to first circulator 202-1 and demodulator 206-i. Second data signal filter 203-2-i is coupled to second circulator 202-2 and demodulator 206-i.

The first data signal filter 203-1-i and the second data signal filter 203-2-i transmit the data signal Di, and filter the data signal D other than the data signal Di and the unmodulated continuous wave C. Any type may be used as long as it is not permeable. The first data signal filter 203-1-i and the second data signal filter 203-2-i may be, for example, bandpass filters whose frequency band is substantially the same as that of the data signal Di.

The first continuous wave filter 204-1-i and the second continuous wave filter 204-2-i transmit the unmodulated continuous wave Ci, and transmit the unmodulated continuous wave C other than the unmodulated continuous wave Ci and the data. signal D is not transmitted. The first continuous wave filter 204-1-i is connected to the first circulator 202-1 and the first modulator 205-1-i. The second continuous wave filter 204-2-i is connected to the second circulator 202-2 and the second modulator 205-2-i.

The first continuous wave filter 204-1-i and the second continuous wave filter 204-2-i transmit the unmodulated continuous wave Ci and transmit the unmodulated continuous wave C other than the unmodulated continuous wave Ci and the data signal. Any material may be used as long as it does not transmit D and D. The first continuous wave filter 204-1-i and the second continuous wave filter 204-2-i may be, for example, bandpass filters whose frequency band is substantially the same as the frequency band of the unmodulated continuous wave Ci. .

FIG. 5 shows the transmission spectra of the first data signal filter 203-1-i and the second data signal filter 203-2-i and the first continuous wave filter 204-1-i and the second continuous wave in the first embodiment. FIG. 10 is a diagram showing an example of a transmission spectrum of a filter 204-2-i;

The transmission spectrum S1_i of the first data signal filter 203-1-i and the second data signal filter 203-2-i is a transmission spectrum that does not transmit the data signal D other than the data signal Di and the unmodulated continuous wave C. be. The transmission spectrum S2_i of the first continuous wave filter 204-1-i and the second continuous wave filter 204-2-i transmit the unmodulated continuous wave Ci and transmit unmodulated continuous waves other than the unmodulated continuous wave Ci. It is a transmission spectrum in which C and data signal D are not transmitted.

Returning to the description of FIG.
The first modulating sections 205-1-1 to 205-1-I and the second modulating sections 205-2-1 to 205-2-I modulate the unmodulated continuous wave C at the same time. More specifically, first modulating section 205-1-i modulates unmodulated continuous wave Ci that has passed through first continuous wave filter 204-1-i, and second modulating section 205-2-p (p is an integer greater than or equal to 1 and less than or equal to I) modulates the unmodulated continuous wave Cp transmitted through the second continuous wave filter 204-2-p. The time at which the first modulating section 205-1-i modulates the unmodulated continuous wave Ci transmitted through the first continuous wave filter 204-1-i and the second modulating section 205-2-i modulating the second continuous wave filter The time at which the unmodulated continuous wave Ci transmitted through 204-2-i is modulated is the same time.

Note that the time at which the first modulating section 205-1-i modulates the unmodulated continuous wave Ci transmitted through the first continuous wave filter 204-1-i and the second modulating section 205-2-p The time at which the unmodulated continuous wave Cp that has passed through wave filter 204-2-p is modulated may be the same time. The time at which the first modulating section 205-1-i modulates the unmodulated continuous wave Ci transmitted through the first continuous wave filter 204-1-i and the second modulating section 205-2-p modulating the second continuous wave filter The time to modulate the unmodulated continuous wave Cp transmitted through 204-2-p may be different if i=p is not true.

The first modulation section 205-1-i is connected to the first continuous wave filter 204-1-i and the third terminal of the second circulator 202-2. The second modulation section 205-2-i is connected to the second continuous wave filter 204-2-i and the third terminal of the first circulator 202-1.

The demodulator 206-i acquires the data signal Di that has passed through the first data signal filter 203-1-i or the second data signal filter 203-2-i, and demodulates the acquired data signal Di. . The demodulator 206-i is connected to the first data signal filter 203-1-i and the second data signal filter 203-2-i. The demodulator 206-i outputs the demodulated data signal Di to a predetermined output destination (not shown).

(Wiring length)
Here, the length of wiring between the functional units provided in the second radio device 20 will be described. In second radio apparatus 20, the length of wiring from first antenna element 201-1 to second circulator 202-2 and the length of wiring from second antenna element 201-2 to first circulator 202-1 are approximately are identical. More specifically, the path length of the first path K1-i and the path length of the second path K2-i are the same. A first path Ki passes from the first antenna element 201-1 to the first circulator 202-1, the first continuous wave filter 204-1-i, and the first modulation section 205-1-i to the second circulator. This is the route leading to 202-2. A second path Ki passes from the second antenna element 201-2 to the second circulator 202-2, the second continuous wave filter 204-2-i, and the second modulation section 205-2-i to the first circulator. This is the route leading to 202-1.

Also, the length of the wiring between the first circulator 202-1 and the first antenna element 201-1 and the length of the wiring between the second circulator 202-2 and the second antenna element 201-2 are the same. be. Hereinafter, the length of wiring between first circulator 202-1 and first antenna element 201-1 will be referred to as first antenna wiring length. Hereinafter, the length of wiring between second circulator 202-2 and second antenna element 201-2 is referred to as the second antenna wiring length.

Also, the length of the wiring from the first antenna element 201-1 to the first modulating section 205-1-i and the length of the wiring from the second antenna element 201-2 to the second modulating section 205-2-i are are identical.

(Regarding the path of propagation)
The propagation paths in the second radio device 20 of the data signal and the unmodulated continuous wave received by the second radio device 20 will be described. Hereinafter, when the first data signal filters 203-1-1 to 203-1-I are not distinguished from each other, they are referred to as the first data signal filter 203-1. Hereinafter, when the second data signal filters 203-2-1 to 203-2-I are not distinguished from each other, they are referred to as the second data signal filter 203-2. Hereinafter, when the first continuous wave filters 204-1-1 to 204-1-I are not distinguished from each other, they are referred to as the first continuous wave filter 204-1. Hereinafter, when the second continuous wave filters 204-2-1 to 204-2-I are not distinguished from each other, they are referred to as the second continuous wave filter 204-2.

First, the propagation paths of the data signal D and the unmodulated continuous wave C received by the first antenna element 201-1 will be described. Data signal D and unmodulated continuous wave C received by first antenna element 201-1 propagate to first circulator 202-1. Data signal D and unmodulated continuous wave C propagated to first circulator 202-1 propagate from first circulator 202-1 to first data signal filter 203-1 and first continuous wave filter 204-1.

Of the data signal D and the unmodulated continuous wave C propagated to the first continuous wave filter 204-1, only the unmodulated continuous wave Ci passes through the first continuous wave filter 204-1-i. The unmodulated continuous wave Ci that has passed through the first continuous wave filter 204-1-i propagates from the first continuous wave filter 204-1-i to the first modulating section 205-1-i.

Unmodulated continuous wave C propagated to first modulation section 205-1-i is modulated by first modulation section 205-1-i for a predetermined period (hereinafter referred to as "first modulation period"). The unmodulated continuous wave Ci modulated by the first modulation section 205-1-i is hereinafter referred to as a first modulated signal V1-i. The first modulated signal V1-i is a radio wave.
The first modulation period may be a different period for each frequency of the unmodulated continuous wave C, or may be the same period regardless of the frequency of the unmodulated continuous wave C.

First modulated signal V1-i propagates from first modulating section 205-1-i to second circulator 202-2. First modulated signal V1-i propagated to second circulator 202-2 propagates from second circulator 202-2 to second antenna element 201-2 and is radiated from second antenna element 201-2.

On the other hand, of the data signal D and the unmodulated continuous wave C propagated to the first data signal filter 203-1-i, only the data signal Di passes through the first data signal filter 203-1-i. Data signal Di that has passed through first data signal filter 203-1-i propagates from first data signal filter 203-1-i to demodulator 206-i. Data signal Di propagated to demodulator 206-i is demodulated by demodulator 206-i.

Next, the propagation paths of the data signal D and the unmodulated continuous wave C received by the second antenna element 201-2 will be described.

Data signal D and unmodulated continuous wave C received by second antenna element 201-2 propagate to second circulator 202-2. Data signal D and unmodulated continuous wave C propagated to second circulator 202-2 propagate from second circulator 202-2 to second data signal filter 203-2 and second continuous wave filter 204-2.

Of the data signal D and the unmodulated continuous wave C propagated to the second continuous wave filter 204-2-i, only the unmodulated continuous wave Ci passes through the second continuous wave filter 204-2-i. The unmodulated continuous wave C transmitted through the second continuous wave filter 204-2-i propagates from the second continuous wave filter 204-2-i to the second modulating section 205-2-i.

Unmodulated continuous wave C propagated to second modulating section 205-2-i is modulated by second modulating section 205-2-i for a predetermined period (hereinafter referred to as "second modulating period"). The second modulation period is a period having the same period start time and period length as the first modulation period. The unmodulated continuous wave Ci modulated by the second modulating section 205-2-i is hereinafter referred to as a second modulated signal V2-i. The second modulated signal V2-i is a radio wave. Hereinafter, when the first modulation period and the second modulation period are not distinguished from each other, they are referred to as a modulation period.
The second modulation period may be a different period for each frequency of the unmodulated continuous wave C, or may be the same period regardless of the frequency of the unmodulated continuous wave C. FIG.

Second modulated signal V2-i propagates from second modulating section 205-2-i to first circulator 202-1. Second modulated signal V2-i propagated to first circulator 202-1 propagates from first circulator 202-1 to first antenna element 201-1 and is radiated from first antenna element 201-1.

(About output waves)
The output wave output by the second radio device 20 will be described by describing the radio wave radiated from the first antenna element 201-1 and the radio wave radiated from the second antenna element 201-2.
In the following, it is assumed that the light source radiates a data signal and an unmodulated continuous wave at time t0. The light source is the first wireless device 10-i.

The time at which the data signal Di and the unmodulated continuous wave Ci radiated from the first radio apparatus 10-i at time t0 reach the first antenna element 201-1 is defined as first arrival time t_in_1-i. The time when the data signal Di and the unmodulated continuous wave Ci radiated from the first radio apparatus 10-i at time t0 reach the second antenna element 201-2 is defined as a second arrival time t_in_2-i.

When the first optical path length L1-i and the second optical path length L2-i are equal, the first arrival time t_in_1-i and the second arrival time t_in_2-i are the same. The first optical path length L1-i is the distance between the first radio device 10-i, which is the light source of the data signal Di and the unmodulated continuous wave Ci, and the first antenna element 201-1. The second optical path length L2-i is the distance between the first radio device 10-i, which is the light source of the data signal Di and the unmodulated continuous wave Ci, and the second antenna element 201-2.
On the other hand, when the first optical path length L1-i and the second optical path length L2-i are different, the first arrival time t_in_1-i and the second arrival time t_in_2-i are different.

Since the length of the first route K1-i and the length of the second route K2-i are the same, and the length of the first antenna wiring and the length of the second antenna wiring are the same, the first arrival time t_in_1 and the second When the arrival time t_in_2 is different, the first modulated signal V1-i and the second modulated signal V2-i start to be emitted at different times. Specifically, when the first arrival time t_in_1 is later than the second arrival time t_in_2 by time Δt, the first emission time t_out_1 is earlier than the second emission time t_out_2 by time Δt. The first radiation time t_out_1 is the time when the first modulated signal V1-i starts to be radiated from the first antenna element 201-1. The second radiation time t_out_2 is the time when the second modulated signal V2-i starts to be radiated from the second antenna element 201-2.

Thus, since the path length of the first path K1-i and the path length of the second path K2-i are the same, and the first antenna wiring length and the second antenna wiring length are the same, the first arrival time A value obtained by subtracting the second arrival time t_in_2-i from t_in_1-i is equal to a value obtained by subtracting the first emission time t_out_1-i from the second emission time t_out_2-i. Therefore, the second radio unit 20 is a van-atta array antenna.

FIG. 6 shows the time variation of the intensity of the unmodulated continuous wave Ci at the first antenna element 201-1 and the intensity of the unmodulated continuous wave Ci at the second antenna element 201-2 in the first embodiment. It is a figure which shows an example with a change.

FIG. 6 shows that the time at which the unmodulated continuous wave Ci reaches the first antenna element 201-1 is L/c more than the time at which the unmodulated continuous wave Ci reaches the second antenna element 201-2. indicates that it is only slow. L is the difference between the first optical path length L1-i and the second optical path length L2-i. Hereinafter, L is referred to as an optical path difference. c represents the speed of light. A difference of L/c means that there is a phase difference of 2πL/λ. λ is the wavelength of the unmodulated continuous wave Ci in the space in which the unmodulated continuous wave Ci propagates. λ is more specifically a dimension of length, and length is a value obtained by dividing λ0 by the dielectric constant of the space in which the unmodulated continuous wave Ci propagates, where λ0 is the wavelength in a vacuum. .

FIG. 7 shows the time variation of the intensity of the first modulated signal V1-i in the first antenna element 201-1 of the first embodiment and the intensity of the second modulated signal V2-i in the second antenna element 201-2. It is a figure which shows an example with a change. More specifically, FIG. 7 shows the first modulated signal V1 at first antenna element 201-1 when the phase difference between first modulated signal V1-i and second modulated signal V2-i is 2πL/λ<2π -i and a second modulated signal V2-i in the second antenna element 201-2. When the phase difference between the first modulated signal V1-i and the second modulated signal V2-i is 2πL/λ<2π, the path difference is L<λ.

FIG. 7 shows that the time at which first modulated signal V1-i begins to be radiated by first antenna element 201-1 is L/L than the time at which second modulated signal V2-i begins to be radiated by second antenna element 201-2. c is earlier.

Since the first arrival time t_in_1-i is later than the second arrival time t_in_2-i by L/c, the first emission time t_out_1-i is earlier than the second emission time t_out_2-i by L/c.

FIG. 7 shows an example of the result of modulation during the modulation period. Specifically, FIG. 7 shows an example of the first modulated signal V1-i, which is an unmodulated continuous wave Ci whose amplitude is amplified by the first modulation section 205-1-i during the modulation period. FIG. 7 shows an example of the second modulated signal V2-i, which is an unmodulated continuous wave Ci whose amplitude is amplified by the second modulating section 205-2-i during the modulation period.

In FIG. 7, periods P1 and P2 are periods in which the phase changes of the first modulated signal V1-i and the second modulated signal V2-i are the same. Further, in FIG. 7, the phase difference between the first modulated signal V1-i and the second modulated signal V2-i in period P1 and period P2 is 2πL/λ. In FIG. 7, in the period P1 and the period P2, the phase of the first modulated signal V1-i is the predetermined phase ξ (ξ is an arbitrary value) and the phase of the second modulated signal V2-i is the phase ξ. The time difference from the time is L/c. Hereinafter, the time difference between the time when the phase of the first modulated signal V1-i is the phase ξ and the time when the phase of the second modulated signal V2-i is the phase ξ in the period P1 and the period P2 is defined as the period P1 and the period P2. is called the time difference between FIG. 7 shows that the first arrival time is L/c later than the second arrival time.

In FIG. 7, the first arrival time is later than the second arrival time by L/c, and the time difference between period P1 and period P2 is L/c. Therefore, the first modulated signal V1-i in the period P1 and the second modulated signal V2-i in the period P2 are in phase and intensify each other in the direction of propagation to the first radio apparatus 10-i.

FIG. 8 shows the first modulated signal V1-i and the second modulated signal V2-i when the phase difference between the first modulated signal V1-i and the second modulated signal V2-i is 2πL/λ≧2π, that is, the path difference is L≧λ. FIG. 10 is a diagram showing an example with a signal V2-i;
In FIG. 8, periods P1 and P2 are periods in which the phase changes of the first modulated signal V1-i and the second modulated signal V2-i are the same. Also, in FIG. 8, the phase difference between the first modulated signal V1-i and the second modulated signal V2-i between the period P1 and the period P2 is θ. However, θ is a value greater than or equal to 0 and less than 2π, and satisfies the relationship of 2πL/λ=θ+2hπ (h is a positive integer) with the optical path difference L and wavelength λ. Therefore, the time difference between the time when the phase of the first modulated signal V1-i is the phase ξ and the time when the phase of the second modulated signal V2-i is the phase ξ in the period P1 and the period P2 is λθ/2πc.

In FIG. 8, the first arrival time is later than the second arrival time by L/c, and the time difference between period P1 and period P2 is λθ/2πc. Therefore, the first modulated signal V1-i in the period P1 and the second modulated signal V2-i in the period P2 are in phase in the direction of propagation to the first radio apparatus 10-i and do not reinforce each other.

(Regarding the distance between the first antenna element and the second antenna element)
Here, the distance between the first antenna element 201-1 and the second antenna element 201-2 will be explained. Hereinafter, the distance between the first antenna element 201-1 and the second antenna element 201-2 is referred to as the first inter-antenna distance d.

If the optical path difference L is less than the wavelength (that is, L<λ), the first modulated signal V1-i in the period P1 and the second modulated signal V2- in the period P2 in the direction of propagation to the first radio device 10-i i is in phase. However, if the optical path difference L is greater than or equal to the wavelength (that is, L≧λ), the first modulated signal V1-i in the period P1 and the second modulated signal V1-i in the period P2 in the direction of propagation to the first radio device 10-i V2-i are not in phase. Therefore, when the first inter-antenna distance d is less than the wavelength, the intensity of the output wave is stronger in the direction of propagation to the first radio device 10-i than when the first inter-antenna distance d is equal to or greater than the wavelength.
If the distance d between antennas is less than the wavelength λ/2, the occurrence of grating lobes is suppressed.

FIG. 9 is a diagram showing an example of the frequency spectrum of output waves in the first embodiment. FIG. 9 shows the frequency spectrum W_i_3 of the output wave. The output wave is a radio wave obtained by modulating the unmodulated continuous wave Ci. Therefore, the frequency spectrum W_i_3 of the output wave is centered at the center of the frequency spectrum W_i_2 of the unmodulated continuous wave Ci and has a wider half width than the frequency spectrum W_i_2 of the unmodulated continuous wave Ci. The description of FIG. 9 ends here.

The second radio apparatus 20 configured in this manner includes first continuous wave filters 204-1-1 to 204-1-I, second continuous wave filters 204-2-1 to 204-2-I, first data Signal filters 203-1-1 to 203-1-I, second data signal filters 203-2-1 to 203-2-I, first modulation sections 205-1-1 to 205-1-I, second modulation Sections 205-2-1 to 205-2-2 and demodulators 206-1 to 206-I, and the path length of the first path K1-i and the path length of the second path K2-i are the same. The first antenna wiring length and the second antenna wiring length are the same, and the first modulation period and the second modulation period are the same. Therefore, the second radio apparatus 20 configured in this manner is capable of receiving data signals and transmitting output waves, even though it is a van-atta array antenna.

The wireless communication system 1 configured in this manner includes I first wireless devices 10 and I second wireless devices 20 . Therefore, the wireless communication system 1 configured in this way is capable of multiple-access two-way communication using the van-atta array. Specifically, the second radio apparatus 20 configured in this manner is capable of frequency-division multiple access (FDMA) using a van-atta array.

(Regarding the case where the second radio device 20 has four or more antenna elements)
Hereinafter, the first antenna element 201-1 and the second antenna element 201-2 in the first embodiment will be referred to as the antenna element 201 when not distinguished from each other. Hereinafter, the first circulator 202-1 and the second circulator 202-2 in the first embodiment are referred to as circulators 202 when not distinguished from each other. Hereinafter, the first data signal filter 203-1 and the second data signal filter 203-2 in the first embodiment will be referred to as the data signal filter 203 when not distinguished from each other. Hereinafter, the first continuous wave filter 204-1 and the second continuous wave filter 204-2 in the first embodiment will be referred to as the continuous wave filter 204 when not distinguished from each other. Hereinafter, when the first modulating sections 205-1-1 to 205-1-I are not distinguished from each other, they are referred to as the first modulating section 205-1. Hereinafter, when the second modulating sections 205-2-1 to 205-2-I are not distinguished from each other, they are referred to as the second modulating section 205-2. Hereinafter, the first modulating section 205-1 and the second modulating section 205-2 in the first embodiment are referred to as the modulating section 205 when not distinguished from each other.

The second radio apparatus 20 in the first embodiment does not necessarily have to have only two antenna elements 201, the first antenna element 201-1 and the second antenna element 201-2. The second radio apparatus 20 in the first embodiment may have an even number of antenna elements 201 of four or more. Hereinafter, the second radio apparatus 20 having 2×N antenna elements 201 (N is an integer equal to or greater than 1) will be referred to as a second radio apparatus 20a. Hereinafter, when distinguishing the 2×N antenna elements 201, they are referred to as the n-th antenna element 201-n (n is an integer of 1 or more and 2×N or less).

2×N antenna elements 201 are arranged in an array. The m-th antenna element 201-m and the (m+1)-th antenna element 201-(m+1) are positioned symmetrically about the center of the array (m is an odd number between 1 and (2×N−1)).

The second radio apparatus 20a includes one filter unit 21 for each pair of antenna elements, that is, the mth antenna element 201-m and the (m+1)th antenna element 201-(m+1). That is, the second radio device 20a includes N filter units 21 . A pair of antenna elements consisting of the mth antenna element 201-m and the (m+1)th antenna element 201-(m+1) is hereinafter referred to as an antenna element pair Gm. Hereinafter, the filter unit 21 through which the radio wave received by the antenna element pair Gm propagates will be referred to as a filter unit 21-m.

FIG. 10 is a diagram showing an example of the functional configuration of the second radio device 20a according to the first embodiment.
The second radio device 20a includes a CPU (Central Processing Unit), a memory, an auxiliary storage device, etc., which are connected via a bus, and executes programs. The second radio apparatus 20a functions as a device including 2×N antenna elements 201, 2×N circulators 202, N filter units 21, and a demodulation unit 22a by executing a program.

The filter unit 21-m includes m-th data signal filters 203-m-1 to 203-m-I, (m+1)th data signal filters 203-(m+1)-1 to 223-(m+1)-I, m-th continuous wave filters 204-m-1 to 204-m-I, (m+1)-th continuous wave filters 204-(m+1)-1 to 204-(m+1)-I, m-th modulation units 205-m-1 to 205-m -I and (m+1)th modulating sections 205-(m+1)-1 to 205-(m+1)-I.

Demodulation unit 22a is different from demodulation unit 22 in that it includes demodulation sections 206a-1 to 206a-I instead of demodulation sections 206-1 to 206-I.
In the following, the same reference numerals as in FIG. 4 are assigned to components having the same functions as those of the first radio apparatus 10, and the description thereof will be omitted.
Hereinafter, when distinguishing between the 2×N circulators 202, it is referred to as the n-th circulator 202-n.

A first terminal of the mth circulator 202-m is connected to the mth antenna element 201-m. The second terminal of the m-th circulator 202-m is connected to the m-th continuous wave filters 204-m-1 to 204-m-I and the m-th data signal filters 203-m-1 to 203-m-I. The third terminal of the mth circulator 202-m is connected to the (m+1)th modulation sections 205-(m+1)-1 to 205-(m+1)-I.

The first terminal of the (m+1)th circulator 202-(m+1) is connected to the (m+1)th antenna element 201-(m+1). The second terminal of the (m+1)th circulator 202-(m+1) is coupled to the (m+1)th continuous wave filters 204-(m+1)-1 to 204-(m+1)-I and the (m+1)th data signal filter 203-(m+1). )-1 to 203-(m+1)-I. The third terminal of the (m+1)th circulator 202-(m+1) is connected to the mth modulating sections 205-m-1 to 205-m-I.

The mth data signal filter 203-mi is connected to the mth circulator 202-m and the demodulator 206a-i. The (m+1)th data signal filter 203-(m+1)-i is connected to the (m+1)th circulator 202-(m+1) and the demodulator 206a-i.

The m-th continuous wave filter 204-mi is connected to the m-th circulator 202-m and the m-th modulator 205-mi. The (m+1)th continuous wave filter 204-(m+1)-i is connected to the (m+1)th circulator 202-(m+1) and the (m+1)th modulator 205-(m+1)-i.

The m-th modulation section 205-mi is connected to the m-th continuous wave filter 204-mi and the third terminal of the (m+1)th circulator 202-(m+1). The (m+1)th modulation section 205-(m+1)-i is connected to the (m+1)th continuous wave filter 204-(m+1)-i and the third terminal of the mth circulator 202-m.
The time at which the n-th modulating section 205-ni modulates the unmodulated continuous wave Ci transmitted through the n-th continuous wave filter 204-ni is the same time regardless of n. That is, the period during which the n-th modulation section 205-ni modulates the unmodulated continuous wave C is the n-th modulation period, and all the n-th modulation periods are the same. That all n-th modulation periods are the same means that the period start times and period lengths of the n-th modulation periods are the same regardless of n.

Note that the n-th modulation period may be a different period for each frequency of the unmodulated continuous wave C, or may be the same period regardless of the frequency of the unmodulated continuous wave C.

The demodulator 206a-i acquires the data signal passed through the first data signal filter 203-1-i to the (2×N)-th data signal filter 203-(2×N)-i, and converts the acquired data signal to demodulate. The demodulation unit 206a-i is connected to 2×N data signal filters 203 from the first data signal filter 203-1-i to the (2×N)-th data signal filter 203-(2×N)-i. . The demodulator 206a-i outputs the demodulated data signal to a predetermined output destination (not shown).

In FIG. 10, thick lines represent I connections between the n-th data signal filters 203-n-1 to 203-n-I and the demodulators 206a-1 to 206a-I.

(Wiring length)
Here, the length of wiring between the functional units provided in the second radio device 20a will be described. Hereinafter, when the n-th data signal filters 203-n-1 to 203-n-I are not distinguished from each other, they are referred to as the n-th data signal filter 203-n. Hereinafter, when the n-th continuous wave filters 204-n-1 to 204-n-I are not distinguished from each other, they are referred to as the n-th continuous wave filter 204-n. Hereinafter, when the n-th modulating sections 205-n-1 to 205-n-I are not distinguished from each other, they are referred to as the n-th modulating section 205-n.

In the second radio device 20a, the length of the wiring from the m-th antenna element 201-m to the m-th modulation unit 205-m-i and the length of the wiring from the (m+1)th antenna element 201-(m+1) to the m-th modulation unit 205-( The wiring length up to m+1)-i is the same. More specifically, the m-th route Km-i and the (m+1)-th route K(m+1)-i have the same route length. The m-th route Km-i is from the m-th antenna element 201-m to the m-th circulator 202-m, the m-th continuous wave filter 204-m and the m-th modulation unit 205-m-i via the (m+1)th ) is the path leading to the circulator 202-(m+1). The (m+1)th path K(m+1)-i is from the (m+1)th antenna element 201-(m+1) to the (m+1)th circulator 202-(m+1), the (m+1)th continuous wave filter 204-(m+1)-i and the (m+1)th modulation section 205-(m+1)-i to the mth circulator 202-m. Furthermore, the length of the n-th route Kn-i is substantially the same regardless of n.

Also, all the n-th antenna wiring lengths are the same. The nth antenna wiring length is the length of the wiring between the nth circulator 202-n and the nth antenna element 201-n.

Also, the length of wiring from the n-th antenna element 201-n to the n-th modulation section 205-ni is the same regardless of n.

(Regarding the propagation path in the second radio device 20a)
The propagation paths in the second radio device 20a of the data signal Di and the unmodulated continuous wave Ci received by the second radio device 20a will be described.

First, the propagation paths of the data signal Di and the unmodulated continuous wave Ci received by the m-th antenna element 201-m will be described. The data signal Di and the unmodulated continuous wave Ci received by the mth antenna element 201-m propagate to the mth circulator 202-m. The data signal Di and the unmodulated continuous wave Ci propagated to the mth circulator 202-m are transferred from the mth circulator 202-m to the mth data signal filter 203-m and the mth continuous wave filter 204-m. -i.

Of the data signal Di and the unmodulated continuous wave Ci that have propagated to the m-th continuous wave filter 204-mi, only the unmodulated continuous wave Ci passes through the m-th continuous wave filter 204-mi. do. The unmodulated continuous wave Ci that has passed through the m-th continuous wave filter 204-mi propagates from the m-th continuous wave filter 204-mi to the m-th modulation section 205-mi.

The unmodulated continuous wave C propagated to the m-th modulating section 205-m-i is modulated by the m-th modulating section 205-m-i for a predetermined period (hereinafter referred to as "m-th modulating period"). Hereinafter, the unmodulated continuous wave Ci modulated by the m-th modulating section 205-m-i is referred to as the m-th modulated signal Vm-i. The m-th modulated signal Vm-i is a radio wave.
Note that the m-th modulation period may be a different period for each frequency of the unmodulated continuous wave C, or may be the same period regardless of the frequency of the unmodulated continuous wave C.

The m-th modulated signal Vm-i propagates from the m-th modulation section 205-m-i to the (m+1)th circulator 202-(m+1). The m-th modulated signal Vm-i propagated to the (m+1)-th circulator 202-(m+1) propagates from the (m+1)-th circulator 202-(m+1) to the (m+1)-th antenna element 201-(m+1), m+1) radiated from antenna element 201-(m+1).

On the other hand, among the data signal Di and the unmodulated continuous wave Ci propagated to the m-th data signal filter 203-mi, only the data signal Di passes through the m-th data signal filter 203-mi. do. The data signal Di that has passed through the mth data signal filter 203-mi propagates from the mth data signal filter 203-mi to the demodulator 206a-i. Data signal Di propagated to demodulator 206a-i is demodulated by demodulator 206a-i.

Next, the propagation paths of the data signal Di and the unmodulated continuous wave Ci received by the (m+1)th antenna element 201-(m+1) will be described.

The data signal Di and the unmodulated continuous wave Ci received by the (m+1)th antenna element 201-(m+1) propagate to the (m+1)th circulator 202-(m+1). The data signal Di and the unmodulated continuous wave Ci propagated to the (m+1)th circulator 202-(m+1) are transferred from the (m+1)th circulator 202-(m+1) to the (m+1)th data signal filter 203-(m+1). )-i and the (m+1)th continuous wave filter 204-(m+1)-i.

Of the data signal Di and the unmodulated continuous wave Ci that have propagated to the (m+1)th continuous wave filter 204-(m+1)-i, only the unmodulated continuous wave Ci is the (m+1)th continuous wave filter 204 -(m+1)-i is transmitted. The unmodulated continuous wave Ci that has passed through the (m+1)th continuous wave filter 204-(m+1)-i passes through the (m+1)th continuous wave filter 204-(m+1)-i to the (m+1)th modulation section 205-( m+1)-i.

The unmodulated continuous wave C propagated to the (m+1)th modulation unit 205-(m+1)-i is a predetermined period (hereinafter referred to as “the (m+1)th modulation period”). -i. Hereinafter, the unmodulated continuous wave Ci modulated by the (m+1)th modulating section 205-(m+1)-i is referred to as the (m+1)th modulated signal V(m+1)-i. The (m+1)th modulated signal V(m+1)-i is a radio wave. Note that all n-th modulation periods are the same. That all the n-th modulation periods are the same means that the period start times and period lengths of the n-th modulation periods are the same regardless of n.
Note that the (m+1)th modulation period may be a different period for each frequency of the unmodulated continuous wave C, or may be the same period regardless of the frequency of the unmodulated continuous wave C.

The (m+1)th modulated signal V(m+1)-i propagates from the (m+1)th modulation section 205-(m+1)-i to the mth circulator 202-m. The (m+1)-th modulated signal V(m+1)-i propagated to the m-th circulator 202-m propagates from the m-th circulator 202-m to the m-th antenna element 201-m, and is radiated from the m-th antenna element 201-m. be done.

(Regarding the output wave of the second radio device 20a)
Hereinafter, the time from when the mth antenna element 201-m receives the unmodulated continuous wave to when the (m+1)th antenna element 201-(m+1) radiates the unmodulated continuous wave is referred to as the mth elapsed time. Hereinafter, the time from when the (m+1)th antenna element 201-(m+1) receives the unmodulated continuous wave to when the mth antenna element 201-m radiates the unmodulated continuous wave is referred to as the (m+1)th elapsed time.

The path length of the n-th path Kn-i is the same regardless of n, the n-th antenna wiring length is the same regardless of n, and the n-th modulation section 205-n passes through the n-th continuous wave filter 204-n. The time to modulate the unmodulated continuous wave is the same regardless of n. Therefore, all nth elapsed times are the same.

Therefore, the second radio device 20a configured in this manner is a van-atta array because all the n-th elapsed times are the same, and the second radio device 20a propagates toward the first radio device 10. form a beam that The beam formed by the second radio device 20a is the output wave.

(flowchart)
FIG. 11 is a flow chart showing an example of the flow of processing in the wireless communication system 1 of the first embodiment. For simplicity of explanation, it is assumed that the second radio device 20 included in the radio communication system 1 is the second radio device 20a. However, the flow of processing is the same. When the second radio apparatus 20 included in the radio communication system 1 is the second radio apparatus 20, this corresponds to the case of N=1.

A first radio apparatus 10-i transmits a data signal Di and an unmodulated continuous wave Ci (step S101). The second radio device 20a receives the data signal Di and the unmodulated continuous wave Ci (step S102). Specifically, the data signal Di and the unmodulated continuous wave Ci reach the nth antenna element 201-n and are received by the nth antenna element 201-n.

The second radio apparatus 20a separates the data signal Di received in step S102 from the unmodulated continuous wave Ci (step S103). Specifically, the data signal Di received by the n-th antenna element 201-n passes through the n-th data signal filter 203-ni, and the unmodulated continuous wave C received by the n-th antenna element 201-n -i passes through the n-th continuous wave filter 204-ni, thereby separating the data signal Di and the unmodulated continuous wave Ci.

The second radio device 20a demodulates the data signal Di (step S104). Specifically, the demodulator 206a-i demodulates the data signal Di that has passed through the n-th data signal filter 203-ni.
The second radio device 20a modulates the unmodulated continuous wave Ci (step S105). Specifically, the n-th modulating section 205-ni modulates the unmodulated continuous wave Ci received by the n-th antenna element 201-n and transmitted through the n-th continuous wave filter 204-ni.

The second radio device 20a radiates the unmodulated continuous wave Ci after being modulated by the n-th modulating section 205-ni (step S106). Specifically, the unmodulated continuous wave Ci modulated by the m-th modulating section 205-m-i is radiated from the (m+1)-th antenna element 201-(m+1)-i. The unmodulated continuous wave modulated by the (m+1)th modulating section 205-(m+1)-i is radiated from the mth antenna element 201-mi.

The first radio device 10-i receives the radio waves emitted from the second radio device 20a (step S107). Specifically, the first radio device 10-i receives radio waves emitted by the second radio device 20a in step S106.

In the second radio apparatus 20a configured in this manner, all n-th paths have the same path length, all n-th antenna wiring lengths are the same, and the n-th modulation section 205-n modulates the n-th continuous wave Since the unmodulated continuous wave C transmitted through the filter 204-n is modulated at the same time, it is a Van Atta array antenna.

The second radio apparatus 20a configured in this manner comprises 2×N antenna elements 201, N filter units 21, and demodulation units 22a, all of which have the same n-th elapsed time. Therefore, the second radio apparatus 20a configured in this way is capable of receiving data signals and transmitting output waves, even though it is a Van Atta array antenna.

The wireless communication system 1 configured in this manner includes I first wireless devices 10 and I second wireless devices 20a. Therefore, the radio communication system 1 configured in this manner is capable of two-way communication using the van-atta array. Specifically, the wireless communication system 1b configured in this manner is capable of frequency-division multiple access (FDMA) using a van-atta array.

In the second radio apparatus 20a configured as described above, one demodulator 206a demodulates the data signal D received by four or more even-numbered antenna elements 201. FIG. Therefore, the second wireless device 20a configured in this way can suppress the increase in size of the device.

(Second embodiment)
FIG. 12 is a diagram showing an example of the system configuration of the wireless communication system 1b of the second embodiment. The wireless communication system 1b includes a first wireless device 10b and second wireless devices 20b-1 to 20b-I. 1, 4, and 10 are given the same reference numerals as in FIGS. 1, 4, and 10, and description thereof is omitted.

The first wireless device 10b includes a CPU (Central Processing Unit), a memory, an auxiliary storage device, etc., which are connected via a bus, and functions as a device by executing a program. The first radio apparatus 10b functions as a device having a data transmission section 101b, a non-modulated wave transmission section 102b, and a reception section 103b by executing a program.

The data transmission unit 101b transmits data signals D-1 to DI to the second radio devices 20b-1 to 20b-I.
Unmodulated wave transmitting section 102b transmits unmodulated continuous waves C-1 to CI to second radio devices 20b-1 to 20b-I.
The receiving unit 103b receives radio waves.

The second radio device 20b-i receives the data signal Di and the unmodulated continuous wave Ci and outputs an output wave. The output wave is a radio wave obtained by modulating the unmodulated continuous wave Ci received by the second radio device 20b-i by the second radio device 20b-i.
The frequency spectra of data signal Di and unmodulated continuous wave Ci are the same as in FIG.

FIG. 13 is a diagram showing an example of the functional configuration of the second radio device 20b-i according to the second embodiment.
The second radio apparatus 20b-i has a filter unit 21b-i instead of the N filter units 21 and a demodulation unit 22b-i instead of the N demodulation units 22a. 2 different from the wireless device 20a.

The 2×N antenna elements 201 are arranged in an array, similar to the second radio apparatus 20a. The mth antenna element 201-m and the (m+1)th antenna element 201-(m+1) are positioned symmetrically about the center of the array.

The second radio apparatus 20b-i includes one filter unit 21b-i for each antenna element pair Gm. That is, the second radio device 20b-i includes N filter units 21b-i. Hereinafter, the filter unit 21b-i through which the radio wave received by the antenna element pair Gm propagates will be referred to as the filter unit 21b-i-m.

Filter unit 21b-i-m is different from filter unit 21-i in that it includes only m-th data signal filter 203-mi instead of m-th data signal filters 203-m-1 to 203-m-I. different. The filter unit 21b-i-m replaces the (m+1)th data signal filters 203-(m+1)-1 to 203-(m+1)-I with only the (m+1)th data signal filter 203-(m+1)-i. It differs from the filter unit 21-i in that it is provided.

The filter unit 21b-i-m differs from the filter unit 21 in that it includes only the m-th continuous wave filter 204-m-i instead of the m-th continuous wave filters 204-m-1 to 204-m-I. The filter unit 21b-i-m includes only the (m+1)-th continuous wave filter 204-(m+1)-i instead of the (m+1)-th continuous wave filter 204-(m+1)-1 to 204-(m+1)-I. It differs from the filter unit 21 in that it is provided.

Filter unit 21b-i-m differs from filter unit 21 in that only m-th modulating section 205-m-i is provided instead of m-th modulating sections 205-m-1 to 205-m-I. Filter unit 21b-i-m includes only (m+1)-th modulating section 205-(m+1)-i instead of (m+1)-th modulating section 205-(m+1)-1 to 205-(m+1)-I. and is different from the filter unit 21 .

Demodulation unit 22b-i differs from demodulation unit 22a in that demodulation unit 206a-i is provided instead of demodulation units 206a-1 to 206a-I.

In the second radio device 20b-i, the wiring lengths between the functional units are the same as in the second radio device 20a. Therefore, all the n-th elapsed times are the same in the second radio apparatus 20b-i as in the second radio apparatus 20a.
Also, in the second radio apparatus 20b-i, all n-th modulation periods are the same as in the second radio apparatus 20a.

FIG. 14 is a diagram showing an example of the functional configuration of the second radio device 20b-i when J=1 in the second embodiment.
The second radio device 20b-i includes a first antenna element 201-1, a second antenna element 201-2, a first circulator 202-1, a second circulator 202-2, and a first data signal filter 203- 1-i, a second data signal filter 203-2-i, a first continuous wave filter 204-1-i, a second continuous wave filter 204-2-i, and a first modulation section 205-1-i , a second modulation section 205-2-i, and a demodulation section 206a-i.

The first data signal filter 203-1-i, the second data signal filter 203-2-i, the first continuous wave filter 204-1-i, and the second continuous wave filter 204-2-i in FIG. , the first modulation section 205-1-i and the second modulation section 205-2-i is the filter unit 22b-i-1.

Transmission spectra of the first data signal filter 203-1-i and the second data signal filter 203-2-i and the first continuous wave filter 204-1-i and the second continuous wave filter in the second radio device 20b-i The transmission spectrum of 204-2-i is the same as in FIG.

Time change of intensity at first antenna element 201-1 of unmodulated continuous wave Ci and time change of intensity at second antenna element 201-2 of unmodulated continuous wave C1-i in second radio device 20b-i is the same as in FIG.

In the second radio device 20b-i, the time variation of the intensity of the first modulated signal V1-i at the first antenna element 201-1 and the time variation of the intensity of the second modulated signal V2-i at the second antenna element 201-2 is the same as in FIG.

FIG. 15 is a diagram showing an example of the frequency spectrum of the output wave emitted by the second radio device 20b-i in the second embodiment. As in FIG. 9, the output wave frequency spectrum W_i_3 is a radio wave obtained by modulating the unmodulated continuous wave Ci. Therefore, as in FIG. 9, the frequency spectrum W_i_3 of the output wave is centered at the center of the frequency spectrum W_i_2 of the unmodulated continuous wave Ci and wider than the half width of the frequency spectrum W_i_2 of the unmodulated continuous wave Ci. Has a half width. However, unlike FIG. 9, the output waves of the frequency spectrum of FIG. 15 are not all output waves radiated by one second radio device 20 or 20a. One frequency spectrum W_i_3 in FIG. 15 is the frequency spectrum of the output wave radiated by one second radio device 20b-i. The description of FIG. 15 ends here.

(flowchart)
FIG. 16 is a flow chart showing an example of the flow of processing in the wireless communication system 1b of the second embodiment.

The first radio apparatus 10b transmits a data signal Di and an unmodulated continuous wave Ci (step S201). The second radio device 20b-i receives the data signal Di and the unmodulated continuous wave Ci (step S202). Specifically, the data signal Di and the unmodulated continuous wave Ci reach the n-th antenna element 201-n of the second radio device 20b-i, and the n-th antenna element of the second radio device 20b-i 201-n.

The second radio apparatus 20b-i separates the data signal Di received in step S102 from the unmodulated continuous wave Ci (step S203). Specifically, in the second radio apparatus 20b-i, the data signal Di received by the n-th antenna element 201-n passes through the n-th data signal filter 203-ni. Further, in the second radio apparatus 20b-i, the unmodulated continuous wave Ci received by the n-th antenna element 201-n passes through the n-th continuous wave filter 204-ni. Thus, the data signal Di and the unmodulated continuous wave Ci are separated.

The second radio device 20b-i demodulates the data signal Di (step S204). Specifically, in the second radio apparatus 20b-i, the demodulator 206a-i demodulates the data signal Di passed through the n-th data signal filter 203-ni.
The second radio device 20b-i modulates the unmodulated continuous wave Ci (step S205). Specifically, in the second radio apparatus 20b-i, the n-th modulating section 205-ni is received by the n-th antenna element 201-n and passed through the n-th continuous wave filter 204-ni. Modulate the continuous wave Ci.

The second radio device 20b-i radiates the unmodulated continuous wave Ci modulated by the n-th modulating section 205-ni (step S206). Specifically, in the second radio apparatus 20b-i, the unmodulated continuous wave Ci modulated by the m-th modulation section 205-m-i is converted to the (m+1)th antenna element 201-(m+1)-i radiated from In the second radio apparatus 20b-i, the unmodulated continuous wave after being modulated by the (m+1)-th modulation section 205-(m+1)-i is radiated from the m-th antenna element 201-m-i.

The first radio device 10-i receives radio waves emitted from the second radio device 20b-i (step S207). Specifically, the first radio device 10-i receives radio waves emitted by the second radio device 20b-i in step S106.

The second radio apparatus 20b-i configured in this manner includes 2×N antenna elements 201, filter units 21b-i-m, and demodulation units 22b-i, and all n-th elapsed times are are identical. Therefore, the second radio apparatus 20b-i configured in this manner is capable of receiving data signals and transmitting output waves while being a van-atta array antenna.

The wireless communication system 1b configured in this manner includes a first wireless device 10b and second wireless devices 20b-1 to 20b-I. Therefore, the wireless communication system 1b configured in this manner is capable of two-way communication using the van-atta array. Specifically, the wireless communication system 1b configured in this manner is capable of frequency-division multiple access (FDMA) using a van-atta array.

(Third Embodiment)
FIG. 17 is a diagram showing an example of the system configuration of a wireless communication system 1c according to the third embodiment. The wireless communication system 1c includes first wireless devices 10-1 to 10-I and a plurality of second wireless devices 20. FIG. 1, 4, 10, 12, and 13, and description thereof will be omitted.

Hereinafter, when distinguishing between the plurality of second radio apparatuses 20, they are referred to as second radio apparatuses 20-j (j is an integer equal to or greater than 1).
In the radio communication system 1c, the second radio device 20-j receives the data signal Di and the unmodulated continuous wave Ci transmitted by the first radio devices 10-1 to 10-I, and outputs the output wave. Output. As in the radio communication system 1, the output wave is a radio wave obtained by modulating the unmodulated continuous wave Ci received by the second radio device 20-j by the second radio device 20-j.

(flowchart)
FIG. 18 is a flow chart showing an example of the flow of processing in the wireless communication system 1c of the third embodiment.

The first radio apparatus 10-i transmits data signal Di and unmodulated continuous wave Ci (step S301). The second radio device 20-j receives the data signal Di and the unmodulated continuous wave Ci (step S302). Specifically, in the second radio apparatus 20-j, the data signal Di and the unmodulated continuous wave Ci reach the n-th antenna element 201-n and are received by the n-th antenna element 201-n. .

The second radio apparatus 20-j separates the data signal Di received in step S102 from the unmodulated continuous wave Ci (step S303). Specifically, in the second radio apparatus 20-j, the data signal Di received by the n-th antenna element 201-n passes through the n-th data signal filter 203-ni. In the second radio apparatus 20-j, the unmodulated continuous wave Ci received by the n-th antenna element 201-n passes through the n-th continuous wave filter 204-ni. Thus, the data signal Di and the unmodulated continuous wave Ci are separated.

The second radio device 20-j demodulates the data signal Di (step S304). Specifically, in the second radio apparatus 20-j, the demodulator 206a-i demodulates the data signal Di passed through the n-th data signal filter 203-ni.
The second radio device 20-j modulates the unmodulated continuous wave Ci (step S305). Specifically, in the second radio apparatus 20-j, the n-th modulation unit 205-ni is received by the n-th antenna element 201-n, and the unmodulated signal transmitted through the n-th continuous wave filter 204-ni Modulate the continuous wave Ci.

The second radio device 20-j radiates the unmodulated continuous wave Ci after being modulated by the n-th modulation unit 205-ni (step S306). Specifically, in the second radio apparatus 20-j, the unmodulated continuous wave Ci modulated by the m-th modulation section 205-m-i is converted to the (m+1)-th antenna element 201-(m+1)-i radiated from In the second radio apparatus 20-j, the unmodulated continuous wave modulated by the (m+1)th modulation section 205-(m+1)-i is radiated from the mth antenna element 201-mi.

The first radio device 10-i receives radio waves emitted from the second radio device 20-j (step S307). Specifically, the first radio device 10-i receives radio waves emitted by the second radio device 20-j in step S106.

The wireless communication system 1c configured in this manner includes first wireless devices 10-1 to 10-I and second wireless devices 20-1 to 20-J. Therefore, the wireless communication system 1c configured in this manner is capable of two-way communication using the van-atta array. Specifically, the wireless communication system 1b configured in this manner is capable of frequency-division multiple access (FDMA) using a van-atta array.

(Modification)
Note that the demodulators 206 and 206a may demodulate the data signal D using a diversity reception scheme. For simplicity of explanation, the demodulator 206 will be specifically explained below. If the power of the first data signal and the power of the second data signal are different, the demodulator 206 may demodulate only the data signal with the higher power. The first data signal is the data signal received by the first antenna element 201-1. The second data signal is the data signal received by the second antenna element 201-2. The demodulator 206 may demodulate only the data signal with high power using any method as long as it can demodulate only the data signal with high power. For example, the demodulator 206 may demodulate only high-power data signals by a selective combining method.

A situation in which the first data signal and the second data signal have different powers occurs, for example, when the direction in which the data signal arrives at the second radio device 20 is not the front. The data signal is emitted from the light source located on the perpendicular bisector of the straight line connecting the first antenna element 201-1 and the second antenna element 201-2. comes from
When the direction in which the data signal arrives at the second radio device 20 is not the front, the time at which the data signal reaches the first antenna element 201-1 and the time at which the data signal reaches the second antenna element 201-2. is different.

The first radio apparatuses 10-1 to 10-I and the first radio apparatus 10b may transmit pilot signals. For example, when the first radio apparatus 10-i or the first radio apparatus 10b transmits a pilot signal, the demodulators 206 and 206a may perform channel estimation using the pilot signal. Also, in such a case, the demodulators 206 and 206a may calculate weights by performing eigenvalue decomposition of the correlation matrix of the received radio waves, and perform maximum ratio combining.

The second radio devices 20a, 20b-i and 20-1 to 20-J do not necessarily have one demodulator 206a or 206 for each frequency, and may have multiple demodulators 206a or 206 for each frequency. good. For example, the second radio apparatus 20a includes a demodulation section 206a, one for each frequency, for each pair of antenna elements 201 of the mth antenna element 201-m and the (m+1)th antenna element 201-(m+1). may

Note that the 2×N antenna elements 201 may be positioned in any manner as long as they are positioned in an array. The 2×N antenna elements 201 may be arranged in a linear array, or may be arranged in a planar array, for example. An array means that 2×N antenna elements 201 are arranged regularly.

Note that the distance between the mth antenna element 201-m and the (m+1)th antenna element 201-(m+1) (hereinafter referred to as the "mth antenna distance") may be less than the wavelength λ. In such a case, as in the case where the distance d between the first antennas is less than the wavelength λ, the first radio device 10-i or the first radio The intensity of the output wave is high in the direction of propagation to the device 10b.
Further, similarly to the case where the distance d between the first antennas is less than the wavelength λ, when the distance between the m-th antennas is less than the wavelength λ/2, generation of grating lobes is suppressed.

The second radio devices 20, 20a, 20b-i and 20-1 to 20-J are examples of radio devices. Note that steps S101, S201 and S301 are an example of the transmission step. Note that steps S102, S202 and S302 are an example of the first receiving step. Note that steps S103, S203 and S303 are an example of the separation step. Note that steps S104, S204, and S304 are examples of demodulation steps. Note that steps S105, S205, and S305 are examples of modulation steps. Note that steps S106, S206, and S306 are examples of the radiation step. Note that steps S107, S207, and S307 are examples of the second receiving step.

The first data signal filter 203-1-i to the (2×N)-th data signal filter 203-(2×N)-i are examples of the i-th modulation signal filter. Note that the n-th data signal filter 203-ni is an example of the i-th data signal filter for the n-th antenna element. The first continuous wave filter 204-1-i to the (2×N)-th continuous wave filter 204-(2×N)-i are examples of the i-th non-modulated wave filter. The n-th continuous wave filter 204-ni is an example of the i-th non-modulated wave filter for the n-th antenna element. The first modulating section 205-1-i to the (2×N)-th modulating section 205-(2×N)-i are examples of the i-th non-modulated wave modulating section. Note that the n-th modulating section 205-ni is an example of the i-th non-modulated wave modulating section for the n-th antenna element. The demodulator 206-i is an example of the i-th modulated signal demodulator.

The unmodulated continuous wave Ci is an example of the i-th unmodulated continuous wave. Note that the data signal Di is an example of the i-th data signal.

All or part of the functions of the first radio devices 10-1 to 10-I and the first radio device 10b and the second radio devices 20, 20a, 20b-i and 20-1 to 20-J are , ASIC (Application Specific Integrated Circuit), PLD (Programmable Logic Device), FPGA (Field Programmable Gate Array), or other hardware. The program may be recorded on a computer-readable recording medium. Computer-readable recording media include portable media such as flexible disks, magneto-optical disks, ROMs and CD-ROMs, and storage devices such as hard disks incorporated in computer systems. The program may be transmitted over telecommunications lines.

Although the embodiment of the present invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design and the like are included within the scope of the gist of the present invention.

1, 1b, 1c... wireless communication system, 10-1 to 10-I, 10b... first wireless device, 101-i, 101b... data transmitter, 102-i, 102b... unmodulated wave transmitter, 103-i , 103b... Receiving unit 20, 20a, 20b-i, 20-1 to 20-J... Second radio apparatus 201... Antenna element 202... Circulator 203... Data signal filter 204... Continuous wave filter 205... Modulator, 206, 206a... Demodulator

Claims (7)

A data transmission unit that transmits a data signal that is a modulated radio wave, a modulated wave transmission unit that transmits an unmodulated continuous wave that is a radio wave having a frequency different from that of the data signal and is an unmodulated radio wave, and receives radio waves. I first wireless devices (I is an integer equal to or greater than 1), and
a second radio device (J is an integer equal to or greater than 1) that is J Van Atta arrays that receive the data signal and the unmodulated continuous wave;
with
A data signal with frequency f1_i (i is an integer equal to or greater than 1) is the i-th data signal, and an unmodulated continuous wave with frequency f2_i is the i-th unmodulated continuous wave,
The second radio device,
2 × N antenna elements (N is an integer of 1 or more) from the first antenna element to the (2 × N)th antenna element for receiving the data signal and the unmodulated continuous wave,
an i-th modulation signal filter that transmits the i-th data signal;
an i-th unmodulated wave filter that transmits the i-th unmodulated continuous wave;
an i-th modulated signal demodulator that demodulates the i-th data signal that has passed through the i-th modulated signal filter;
an i-th non-modulated wave modulation unit that modulates the i-th non-modulated continuous wave that has passed through the i-th non-modulated wave filter;
with
The second radio device radiates the i-th unmodulated continuous wave after being modulated by the i-th unmodulated wave modulation unit,
The first radio device receives the i-th unmodulated continuous wave after being modulated by the second radio device,
the timing at which the data transmission unit transmits the data signal and the timing at which the modulated wave transmission unit transmits the unmodulated continuous wave are simultaneous;
The timing at which the n antenna elements (n is an integer of 1 or more and 2×N or less) receives the data signal and the timing at which the unmodulated continuous wave is received are the same.
wireless communication system. The second radio device has 2×N antenna elements (N is an integer equal to or greater than 1) from a first antenna element to a (2×N)th antenna element for receiving the data signal and the unmodulated continuous wave. prepared,
The second radio device includes, as the i-th non-modulated wave filter, an i-th non-modulated wave filter for the n-th antenna element that transmits the i-th non-modulated continuous wave received by the n-th antenna element,
The second wireless device, as the i-th unmodulated wave modulation unit, is an i-th unmodulated wave modulation unit for an n-th antenna element that modulates the i-th unmodulated continuous wave that has passed through the i -th unmodulated wave filter. with
The 2×N antenna elements are arranged in an array, and the m-th antenna element (m is an odd number of 1 or more and (2×N) or less) and the (m+1)-th antenna element are symmetrical about the center of the array. An antenna element located at a position,
The i-th unmodulated continuous wave received by the m-th antenna element is modulated by the i-th unmodulated wave modulation unit for the m-th antenna element after passing through the m-th continuous wave filter CF-i, and radiated from the (m+1)-th antenna element after being modulated by the i-th non-modulated wave modulation unit for the m-th antenna element ,
The i-th unmodulated continuous wave received by the (m+1)th antenna element is modulated for the (m+1)th antenna element after passing through the (m+1)th continuous wave filter CF-i. radiated from the m-th antenna element after being modulated by the i-th unmodulated wave modulation unit for the (m+1)-th antenna element,
A wireless communication system according to claim 1 . The second radio device has 2×N antenna elements (N is an integer equal to or greater than 1) from a first antenna element to a (2×N)th antenna element for receiving the data signal and the unmodulated continuous wave. prepared,
The second radio apparatus, as the i-th modulated signal filter, is for the n-th antenna element that transmits the i-th data signal received by the n-th antenna element (n is an integer of 1 or more (2×N) or less). an i-th data signal filter of
The i-th modulated signal demodulator demodulates the i-th data signal that has passed through the i-th modulated signal filter for the n-th antenna element,
The radio communication system according to claim 1 or 2. The distance between the m-th antenna element and the (m+1)-th antenna element is less than the wavelength of the unmodulated continuous wave in the space in which the unmodulated continuous wave propagates.
A wireless communication system according to claim 3. The period during which the i-th non-modulated wave modulation unit for the n-th antenna element modulates the i-th non-modulated continuous wave is defined as the n-th modulation period, and all n-th modulation periods are the same.
A wireless communication system according to claim 2. A wireless communication method performed by the wireless communication system according to claim 1,
a transmission step in which I first wireless devices provided in the wireless communication system transmit a data signal that is a modulated radio wave and an unmodulated continuous wave that is an unmodulated radio wave;
a first receiving step in which a second radio device included in the radio communication system receives the data signal and the unmodulated continuous wave;
a separation step in which the second radio device separates the data signal and the unmodulated continuous wave;
a demodulation step in which the second radio device demodulates the data signal;
a modulating step in which the second radio device modulates the unmodulated continuous wave;
a radiating step in which the second radio device radiates the unmodulated continuous wave after being modulated in the modulating step;
a second receiving step in which the first radio device receives the unmodulated continuous wave radiated in the radiating step;
having
wireless communication method. A Van Atta array comprising 2×N antenna elements (N is an integer of 1 or more) from the first antenna element to the (2×N)th antenna element,
A data signal having a frequency f1_i (i is an integer equal to or greater than 1), which is transmitted by a data transmission unit that transmits a data signal that is a modulated radio wave, is defined as an i-th data signal, and a frequency different from that of the data signal. The non-modulated continuous wave of frequency f2_i transmitted by the modulated wave transmitting unit that transmits the non-modulated continuous wave that is a radio wave that is not modulated is the i-th non-modulated continuous wave,
an i-th modulation signal filter that transmits the i-th data signal;
an i-th unmodulated wave filter that transmits the i-th unmodulated continuous wave;
an i-th modulated signal demodulator that demodulates the i-th data signal that has passed through the i-th modulated signal filter;
an i-th non-modulated wave modulation unit that modulates the i-th non-modulated continuous wave that has passed through the i-th non-modulated wave filter;
with
The n -th antenna element (n is an integer of 1 or more and 2×N or less) receives the data signal and the unmodulated continuous wave,
The timing at which the data transmission unit transmits the data signal and the timing at which the modulated wave transmission unit transmits the unmodulated continuous wave are simultaneous,
The timing at which the n -th antenna element receives the data signal and the timing at which the unmodulated continuous wave is received are the same.
wireless communication device.

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