JPH0680968B2 - Optically controlled phased array antenna - Google Patents

Description

The present invention relates to an optically controlled phased array antenna.

[Prior Art] In recent years, as a land mobile station antenna and satellite antenna for automobiles of a mobile satellite communication system, the antenna is small and lightweight, can withstand vibration, and has a wide angle for tracking a partner station. There is a demand for a high-performance and highly-functional antenna that can perform beam scanning at high speed and can form a beam pattern having a desired shape according to communication conditions. These requirements are, in general, for a phased array antenna in which a plurality of antennas are arranged in parallel for beam scanning in which the radiation direction is changed, so that the beam direction becomes a desired direction, that is, by using the plurality of antennas. It is realized by appropriately shifting the phase of each transmission wireless signal or each reception wireless signal (hereinafter referred to as phase shift) so that each transmission wireless signal to be transmitted or received or each reception wireless signal is radiated or received in the same phase. it can.

For example, assuming that a transmission radio signal having a transmission frequency ωr output from a transmitter is represented by the following equation, cosωrt (1) The excitation current output to a plurality of n antennas in a phased array antenna is expressed by the following equation. Need to be represented.

cos (ωrt + θk), k = 1,2,3, ..., n (2) where θk is the amount of phase shift given to the excitation current of each antenna to obtain the desired beam direction, and the plurality of antennas are used. Is set according to the deviation angle of the beam direction so that each transmission radio signal or each reception radio signal transmitted and received using the radiated signal is radiated or received in phase. Therefore, by forming each excitation current represented by the above equation (2) capable of independently controlling each phase θk from the transmission radio signal and outputting each excitation current to each antenna, the transmission phased An array antenna can be constructed.

The conventional phased array antenna uses a microwave feed line for transmitting a microwave signal and a microwave phase shifter for shifting the phase of the microwave signal. In this case, when the number of array antenna elements increases,
In order to significantly increase the number of the power supply lines and the phase shifters and to realize the control circuit for the phase shift in a predetermined size, it is necessary to mount these at high density. At this time, since the power supply lines are close to each other, there is a possibility that microwave signals flowing in the respective lines interfere with each other between the adjacent lines. In order to prevent this, the feed line of the conventional phased array antenna is configured with an optical fiber cable that is resistant to interference, and the control circuit for phase shift is an optical integrated circuit that uses phase control and interference of optical signals. An optical control type phased array antenna to be realized is proposed in Japanese Patent Application No. 63-36218.

FIG. 7 is a block diagram of a proposed conventional optically controlled transmission phased array antenna device. This conventional optically controlled transmission phased array antenna uses one semiconductor laser diode 1 as a coherent light source, and the branch optical waveguides 12, 13, 15 which are optical signal processing circuits required for beam scanning. , Multiplexing optical waveguides 18a to 1
8d, optical frequency shifter 14, optical phase shifters 16a to 16d, 17a to 17
d, and the optical waveguides 21 to 24, 25a to 25d, 26a to 26d, 27
a to 27d, 28a to 28d, 29a to 29d are respectively dielectric substrates
The feature is that it is integrated and provided on 100.

In FIG. 7, the optical signal cos ωct output from the laser diode 1 enters the branch optical waveguide 12 via the input end 11 of the dielectric substrate 100 and the optical waveguide 21, and then is split into two, and the above-mentioned split is performed. One optical signal is output to the branch optical waveguide 13 via the optical waveguide 22, and the other optical signal thus distributed is branched via the optical waveguide 23, the optical frequency shifter 14, and the optical waveguide 24. Is output to. Here, the optical signal incident on the optical frequency shifter 14
Cosωct is frequency-shifted by the frequency of the microwave signal cosωrt modulated by the baseband signal in the transmission device 2, and the optical signal cos (ωc + ωr) t is output.

The branching optical waveguide 13 divides the incident optical signal into four, and each of the optical waveguides 25a to 25d, the optical phase shifters 16a to 16d, and the optical waveguides 26a to 26d are used to divide the optical signal into four beams. Output to the input terminal of 1. Further, the branch optical waveguide 15 divides the incident optical signal into four, and the optical waveguides 27a to 27a are respectively divided.
7d, the optical phase shifters 17a to 17d, and the optical waveguides 28a to 28d are output to the respective second input ends of the multiplexing optical waveguides 18a to 18d.

Here, the optical phase shifters 16a to 16d are respectively for performing the above-mentioned phase shift, and the variable voltage source 4 for supplying the direct-current voltage for controlling the phase shift amount to the optical phase shifters 16a to 16d, respectively.
Is connected to a direction control device 3 for controlling the beam direction of the phased array antenna, and the direction control device 3 is connected to an input device 80 for inputting the beam direction information. Here, the variable voltage source 4 is, as is known, a beam deviation in the beam direction so that each transmission radio signal or each reception radio signal transmitted / received using the plurality of antennas 8a to 8d is radiated or received in phase. It comprises four variable voltage sources 4a to 4d in order to supply different DC voltages for controlling the phase shift amounts of the four optical phase shifters 16a to 16d according to the angle of shift. For example, when a plurality of antennas 8a to 8d are juxtaposed on one straight line, the beam deviation when the direction orthogonal to the juxtaposed straight line is the central beam direction and the beam deviation angle is 0 °. There is a proportional relationship between the shift angle (for example, in the range of -90 ° to + 90 °) and each DC voltage generated by the variable voltage sources 4a to 4d, and each proportional constant is proportional to a predetermined proportional coefficient. Then, there is a proportional relationship that increases in proportion, or a proportional relationship that decreases in inverse proportion with a predetermined inverse proportional coefficient. Generally speaking, the proportional constant is, as is known, based on the arrangement shape of the plurality of antennas 8a to 8d so that each transmission radio signal to be transmitted or received or each reception radio signal is radiated or received in phase. It is determined in advance for each of the variable voltage sources 4a to 4d.

Each of the optical phase shifters 16a to 16d has a phase shift amount θk proportional to the DC voltage applied from the variable voltage sources 4a to 4d, where k is the optical phase shifter 16a to 16d. The phase-shifted optical signal cos (ωct + θk) is output after phase shifting by a natural number from 1 to 4 corresponding to 16d. Here, each phase shift amount θk is proportional to the DC voltage applied from the variable voltage sources 4a to 4d, but each proportional coefficient (hereinafter, referred to as phase shift amount proportional constant) is the same.

In the following description of the phase of the signal, the phase shift amount of the optical phase shifter 17a to 17d for phase correction, and the branch optical waveguides 12, 13,
15, optical waveguides 22 to 24, 25a to 25d, 26a to 26d, 27a to
The amount of delay in 27d, 28a to 28d is not considered.

Further, the optical phase shifters 17a to 17d are respectively connected to the branch optical waveguide 12
Is a phase shifter for phase correction for correcting the respective optical signals divided in two at the branching section of the optical waveguides 18a to 18d so as to have the same optical path difference until reaching the multiplexing sections. Therefore, a DC voltage for phase correction is supplied to each of the optical phase shifters 17a to 17d. Here, the variable voltage source 5 supplies a DC voltage for controlling the optical phase shifters 17a to 17d,
It consists of four variable voltage sources 5a to 5d. Note that the amount of phase shift for the above-described phase shift correction may be determined in advance, for example, at the time of manufacturing, and may be set and adjusted, as is known. The former case is illustrated in FIG. 7 and FIGS. 1 to 5 of the embodiment described later.

Further, the combined optical waveguides 18a to 18d combine the two incident optical signals, and combine the combined optical signals cos (ωc +
Let ωr) t + cos (ωct + θk) be the optical waveguides 29a to 29d,
And output to the photoelectric converters 6a to 6d via the output terminals 19a to 19d. Each of the photoelectric converters 6a to 6d square-detects the incident optical signal cos (ωc + ωr) t + cos (ωct + θk) and removes the direct-current component to obtain each microwave signal cos (ωrt− θk) is output via the power amplifiers 7a to 7d to the antennas 8a to 8d juxtaposed in line. This allows each microwave signal to
Emitted from 8a to 8d.

In the optically controlled transmission phased array antenna configured as described above, when the operator inputs the beam deviation angle information of the beam direction of the phased array antenna to the input device 80, the beam deviation angle information is used for direction control. In response to this, the direction control device 3 causes the direction control device 3 to set each of the preset proportional constants with respect to the input beam deviation angle based on the beam deviation angle information of the beam direction. Each of the predetermined DC voltage proportional to
Through 4d to the optical phase shifters 16a through 16d. Thereby, the above-mentioned phase shift is performed, and a plurality of microwave signals can be radiated in the same phase from the antennas 8a to 8d at the beam phase angle in the desired beam direction input by the operator as described above. Therefore, by configuring as shown in FIG. 1, it is possible to realize an optically controlled transmission phased array antenna capable of controlling beam scanning.

[Problems to be Solved by the Invention] The above-described conventional phased array antenna has the following problems.

First, the variable voltage sources 4a to 4d and 5a to 5d for driving the optical phase shifters 16a to 16d and 17a to 17d are equal to the number of antennas of 2
You need double the number. Therefore, as the number of antennas increases, the number of the power sources increases significantly, which significantly increases the weight of the phased array antenna including the power sources and significantly increases the cost of the phased array antenna. There was a point. Also, due to the increase in the number of the power supplies, the control lines between the direction control device 3 and the variable voltage sources 4a to 4d, 5a to 5d, the variable voltage sources 4a to 4d and the optical phase shifters 16a to 16a. 16d
And the variable voltage sources 5a to 5d.
There is a problem that the number of voltage supply lines between the optical phase shifters 17a to 17d and the number of the voltage supply lines are significantly increased, the wiring is complicated, and the size of the phased array antenna is increased.

Secondly, in this phased array antenna, the direction control circuit 3 for controlling the variable voltage source is provided for beam scanning. However, as the number of variable voltage sources to be controlled increases, the control is performed. There is a problem that the control circuit 3 becomes complicated and the circuit configuration of the control circuit 3 becomes complicated, and the processing speed decreases.

Therefore, the above-mentioned optical control type phased array antenna of the conventional example is unsuitable particularly when it is mounted on a mobile body or a satellite and applied to mobile communication.

An object of the present invention is to solve the above problems and to provide a light control type phased array antenna which can be constituted by a simple circuit as compared with a conventional example, is small and lightweight, and can control beam scanning easily. Especially.

[Means for Solving the Problem] An optically controlled phased array antenna according to the present invention is an optical signal generation means (1) for generating a coherent optical signal in a phased array antenna including a plurality of antennas (8a-8d). )
A first distribution means (12) for distributing an optical signal output from the optical signal generation means (1) into two optical signals, and one of the first output means (12) output from the first distribution means (12). Second distribution means (13) for distributing an optical signal into a plurality of first optical signals
A voltage generating means (4) for generating and outputting a DC voltage proportional to the beam deviation angle of the phased array antenna input thereto; and a plurality of first distribution means (13) for outputting from the second distributing means (13). Of the plurality of antennas (8a-8d) for the DC voltage output from the voltage generating means (4).
Phase shift amounts proportional to the phase shift amounts proportional to the plurality of predetermined proportional factors so that the plurality of transmission radio signals transmitted from the plurality of antennas (8a-8d) are radiated in phase based on the arrangement relationship of A plurality of phase shifting means (16a-16d) and a shifting means (14, 16d) for shifting the frequency of the other optical signal output from the first distributing means (12) by the frequency of the input transmission radio signal. 14a), a third distributing means (15) for distributing the optical signal output from the shift means (14, 14a) to the plurality of second optical signals, and the plurality of phase shifting means (16a- Each first output from 16d)
A plurality of multiplexing means (18a-18d) for respectively multiplexing the second optical signal output from the third distributing means (15) and the plurality of multiplexing means (18a). -18d) and a plurality of photoelectric conversion means (6a-6d) for detecting a plurality of optical signals and outputting a plurality of transmission radio signals to the plurality of antennas (8a-8d), respectively. , The plurality of transmission radio signals output from the plurality of photoelectric conversion means (6a-6d) are radiated from the plurality of antennas (8a-8d) at the beam deviation angle of the input phased array antenna. Characterize.

[Operation] In the phased array antenna configured as described above, the first distribution means (12) distributes the optical signal output from the optical signal generation means (1) into two optical signals. The second distributing means (13) distributes one optical signal output from the first distributing means (12) into a plurality of first optical signals. On the other hand, the voltage generating means (4) generates and outputs a DC voltage proportional to the beam deviation angle of the phased array antenna that is input.

Next, the plurality of phase shifting means (16a-16d) are connected to the second
Of the plurality of first optical signals output from the distribution means (13) of the plurality of antennas (8a-8d) with respect to the DC voltage output from the voltage generation means (4). Based on the above, the plurality of transmission radio signals transmitted from the plurality of antennas (8a-8d) are phase-shifted by respective phase shift amounts proportional to each other by a plurality of predetermined proportional coefficients so as to be radiated in phase. The shift means (14, 14a) is the first
The other optical signal output from the distributing means (12) is frequency-shifted by the frequency of the input transmission radio signal. Further, the third distribution means (15) is provided with the deviation means (14, 1).
4a) outputs the optical signal to the plurality of second optical signals, and the plurality of multiplexing means (18a-18d) outputs the plurality of phase shifting means (16a-16d). The first optical signal and the respective second optical signals output from the third distributing means (15) are multiplexed. Finally, the plurality of photoelectric conversion means (6a-6d) are connected to the plurality of multiplexing means (18a-18
A plurality of optical signals output from d) are detected and a plurality of transmission radio signals are output to the plurality of antennas (8a-8d).

Thereby, the plurality of transmission radio signals output from the plurality of photoelectric conversion means (6a-6d) are radiated from the plurality of antennas (8a-8d) at the beam shift angle of the input phased array antenna. . That is, by changing the beam deviation angle of the input phased array antenna, the voltage generating means (4) changes the generated DC voltage in response to this. At this time, the plurality of phase shifting means (16a-16d) respectively output the plurality of first optical signals output from the second distributing means (13).
A plurality of transmission radio signals transmitted from the plurality of antennas (8a-8d) based on the arrangement relationship of the plurality of antennas (8a-8d) with respect to the DC voltage output from the voltage generation means (4). Are phase-shifted by a plurality of proportional coefficients that are proportional to each other and are proportional to each other. Thereby, the plurality of transmission radio signals output from the plurality of photoelectric conversion means (6a-6d) are transmitted to the plurality of antennas (8a-
8d) is radiated at the beam deviation angle of the phased array antenna input above.

[Embodiment] First Embodiment FIG. 1 is a block diagram of an optically controlled transmission phased array antenna according to a first embodiment of the present invention. In FIG. 1, the same elements as those in FIG. 7 are the same. The code is attached.

The phased array antenna of the first embodiment is the seventh
The difference from the conventional phased array antenna in the figure is that
One variable voltage source 4 is provided in place of the variable voltage sources 4a to 4d, and a DC voltage for controlling the amount of phase shift is supplied from this variable voltage source 4.
The optical signals input in response to the same DC voltage are applied to the respective optical phase shifters 16a to 16d for shifting the phase shift amounts different from each other, and one variable voltage source is used instead of the variable voltage sources 5a to 5d. Each of the optical phase shifters 17a is provided with a voltage source 5 and shifts the direct current voltage for phase correction from the variable voltage source 5 in response to the same direct current voltage by different phase shift amounts. To 17d via the phase fine adjustment variable resistors Ra to Rd, respectively, and other configurations are the same as those in FIG.

FIG. 6A shows optical phase shifters 16a to 16d (hereinafter collectively referred to as "optical phase shifters").
16 3] is a perspective view showing the basic configuration of FIG.

In FIG. 6 (A), a substantially semi-cylindrical optical waveguide 110 is formed on the dielectric substrate 100, covers a part of the optical waveguide 110, and the longitudinal direction of the optical waveguide 110 is parallel to the longitudinal direction of the electrode 120. Then, a rectangular electrode 120 having a longitudinal length 1 is formed on the dielectric substrate 100. The length of the electrode 120 is set so as to be separated from one side in the longitudinal direction of the electrode 120 by a distance d in the direction perpendicular to the longitudinal direction and the longitudinal direction of the electrode 120 is parallel to the longitudinal direction of the electrode 130. A rectangular electrode 130 having l is formed.
Here, a voltage source 140 for applying a DC voltage V is connected to the electrodes 120 and 130.

In the optical phase shifter 16 configured as described above, the optical waveguide
When an optical signal of wavelength λ is input to 110, a predetermined electric field is applied in a direction substantially perpendicular to the optical axis of the optical waveguide 110, whereby the phase of the optical signal traveling through the optical waveguide 110 is expressed by the following equation. The phase is shifted by the phase shift amount θ.

θ = π / λ / d · n ³ · γ · Γ · l · V [rad] (3) where n is the refractive index of the dielectric substrate 100 and γ is the dielectric substrate 1
The electro-optic coefficient of 00, Γ is the applied electric field reduction coefficient determined from the positional relationship between the optical waveguide 110 and the electrodes 120 and 130. Therefore, when the applied voltage V is constant, the phase shift amount θ of the optical phase shifter 16 is changed by changing the distance d between the electrodes, the electrode length l, or the applied electric field reduction coefficient Γ. Can change.

FIG. 6B is a plan view showing the configuration of the optical phase shifters 16a to 16d used in this embodiment.

In FIG. 6 (B), the optical phase shifters 16a to 16d have the same basic configuration as the optical phase shifter 16 in FIG. 6 (A).
The distances between the electrodes of the optical phase shifters 16a to 16d are different from each other. Optical phase shifter 1 with optical waveguide 110a and electrodes 120a and 130a
6a is configured, and the optical phase shifter 16b is configured by the optical waveguide 110b and the electrodes 120b and 130b. Further, the optical waveguide 110c and the electrodes 120c and 130c constitute an optical phase shifter 16c, and the optical waveguide 11c
The optical phase shifter 16d is configured by 0d and the electrodes 120d and 130d.
Here, the distances between the electrodes of the optical phase shifters 16a to 16d are set to d, d / 2, d / 3, and d / 4, respectively. Each electrode 120a,
The electrodes 120b, 120c, 120d are connected to the voltage application line 150, while the electrodes 130a, 130b, 130c, 130d are connected to the voltage application line 160. Further, the variable voltage source 4 is connected to the voltage application lines 150 and 160.

When the optical signals cos (ωct) are input to the optical waveguides 110a to 110d of the optical phase shifters 16a to 16d configured as described above, the optical phase shifters 16a to 16d respectively output the optical signals cos (ωc
t + θ), cos (ωct + 2θ), cos (ωct + 3θ), cos
Output (ωct + 4θ). That is, by applying the same DC voltage V from the variable voltage source 4 to each of the optical phase shifters 16a to 16d, each of the optical phase shifters 16a to 16d, as described above,
The input optical signals are phase-shifted by the amounts of phase shifts θ, 2θ, 3θ, 4θ which are different from each other and are proportional to the DC voltage V and output.
That is, each of the optical phase shifters 16a to 16d has a phase shift amount θ, 2θ which is proportional to the incident optical signal with respect to the DC voltage applied from the variable voltage source 4 by a predetermined different phase shift amount proportional constant. , 3θ, 4θ, the phase-shifted optical signal is output.

Here, each phase shift amount of the optical phase shifters 16a to 16d is proportional to the DC voltage applied from the variable voltage source 4, and the phase shift amount proportional constant is such that each transmission radio signal to be transmitted has the same phase. It is previously determined for each of the optical phase shifters 16a to 16d based on the arrangement shape of the plurality of antennas 8a to 8d so as to be radiated. For example, when a plurality of antennas 8a to 8d are arranged side by side on a straight line, as is well known, the phase shift amount proportional constants for the optical phase shifters 16a to 16d are proportional to each other with a predetermined proportional coefficient. It becomes a proportional relationship that increases or a proportional relationship that decreases in inverse proportion to a predetermined inverse proportional coefficient. That is, in the first embodiment, the phase shift amount proportional constants for the respective optical phase shifters 16a to 16d are 1, 2, 3, and 4 (see, for example, FIG. 6 (B)).

Further, the optical phase shifters 17a to 17d are configured similarly to the optical phase shifters 16a to 16d in FIG. 6B, and the optical phase shifters 17a to 17d are provided.
A variable voltage source 5 is connected to each of them via the phase fine adjustment variable resistors Ra to Rd. Therefore, from the variable voltage source 5 to the respective optical phase shifters 17a to 17d, from the DC voltage V'to the variable resistors Ra to 17d.
By applying the DC voltage finely adjusted by Rd, the optical phase shifters 17a to 17d are different from each other in the input optical signal as described above, and are proportional to the DC voltage finely adjusted from the DC voltage V '. The phase is shifted and output.

In the optically controlled transmission phased array antenna configured as described above, when the operator inputs the beam deviation angle information of the beam direction of the phased array antenna to the input device 80, the information is output to the direction control device 3. In response to this, the direction control device 3 outputs a beam deviation angle signal proportional to the beam deviation angle to the variable voltage source 4 based on the beam deviation angle information of the beam direction. The variable voltage source 4 is proportional to the beam shift angle signal and each optical phase shifter 16
The same DC voltage for driving a to 16d is generated and applied to each optical phase shifter 16a to 16d. In response to this, each of the optical phase shifters 16a to 16d causes the incident optical signal to be proportional to the DC voltage applied from the variable voltage source 4 by each of the preset phase shift amount proportional constants. Phase shift amount θ, 2θ, 3θ, 4θ
After phase-shifting only, the phase-shifted optical signal is output. As a result, the plurality of microwave signals radiated from the antennas 8a to 8d are radiated in phase with the beam deviation angle in the desired beam direction input by the operator as described above. Therefore,
An optically controlled phased array antenna capable of controlling beam scanning can be realized.

Here, each phase shift amount of the optical phase shifters 16a to 16d is proportional to the DC voltage applied from the variable voltage source 4, and the phase shift amount proportional constant is such that each transmission radio signal to be transmitted has the same phase. It is predetermined for each of the optical phase shifters 16a to 16d based on the arrangement shape of the plurality of antennas 8a to 8d so as to be radiated.
Therefore, when the input beam deviation angle information changes,
The beam deviation angle signal changes in proportion to the beam deviation angle, and further, the same DC voltage applied to each optical phase shifter 16a to 16d changes in proportion to the beam deviation angle signal. To do. When the applied DC voltage is changed, each phase shift amount of the optical phase shifters 16a to 16d is proportional to the applied DC voltage and the phase shift amount θ ′, which is proportional to the preset phase shift amount proportional constant, 2
θ ′, 3θ ′, 4θ ′. This allows the antenna
A plurality of microwave signals radiated from 8a to 8d are radiated in phase with the beam deviation angle in the changed beam direction.

As described above, in the transmission phased array antenna of this embodiment, the four variable voltage sources 4a to 4d of the conventional example are used.
Since one variable voltage source 4 is used instead of the above, and one variable voltage source 5 is used instead of the four variable voltage sources 5a to 5d of the conventional example, the phased array antenna is compared with the conventional example. It has the advantage that it can be made smaller and lighter.

Further, instead of the plurality of pairs of voltage application lines of the conventional example, which are connected to the pair of optical phase shifters 16a to 16d or 17a to 17d, only one pair of voltage application lines need be formed. The structure of the voltage application line on the dielectric substrate 100 is simplified.

Further, in the conventional example, the direction control device 3 needs to send a control signal to a large number of variable voltage sources 4a to 4d and 5a to 5d, but in the present embodiment, the two variable voltage sources 4,5. Therefore, the circuit configuration of the direction control device 3 can be simplified and the processing speed of the device 3 can be increased.

Therefore, the optically controlled transmission phased array antenna of this embodiment has a simpler circuit configuration and a smaller size than the conventional example.
Since it is lightweight and has no moving parts and is not easily affected by vibration, it can be used as a phased array antenna mounted on a mobile body or a satellite.

In the first embodiment described above, the semiconductor laser diode 1 is used as a light source that outputs a coherent optical signal, but the present invention is not limited to this, and a gas laser may be used.

In the first embodiment described above, the distances between the electrodes of the optical phase shifters 16a to 16d are made different from each other, and the optical phase shifters 16a to 16d are changed.
Change the phase shift amount for each phase shift, but the invention is not limited to this, and the electrode length l or the applied electric field reduction coefficient Γ
May be made different from each other to change the phase shift amounts at which the optical phase shifters 16a to 16d perform the phase shifts.

In the above first embodiment, the four antennas 8a to 8d
However, the present invention is not limited to this, and a plurality of antennas may be arranged side by side in an example or in a plane. In this case, depending on the number of antennas,
Optical phase shifters 16a to 16d, 17a to 17d, power amplifiers 7a to 7
d, it is necessary to provide each of the multiplexing optical waveguides 18a to 18d, the photoelectric converters 6a to 6d, and the power amplifiers 7a to 7d. Further, since it is necessary to control in two orthogonal directions, it is necessary to provide two variable voltage sources 4. Note that only one variable voltage source 5 needs to be provided.

Second Embodiment FIG. 2 is a block diagram of an optically controlled transmission phased array antenna according to a second embodiment of the present invention. In FIG. 2, the same parts as those in FIG. is doing.

The optically controlled transmission phased array antenna of the second embodiment differs from the optically controlled transmission phased array antenna of the first embodiment of FIG. 1 in that the branched optical waveguide of FIG.
An optical frequency shifter 14a that shifts the frequency of the incident optical signal between the branch optical waveguide 12 and the branch optical waveguide 13 by the frequency of the microwave signal output from the microwave signal generator 30 and not frequency-modulated by the baseband signal. And also the first
An optical frequency shifter 14b for shifting the frequency of the incident optical signal by the frequency of the baseband signal output from the baseband signal generator 31 is provided between the branched optical waveguide 12 and the branched optical waveguide 13 in the figure. That is.

Therefore, one optical signal distributed by the branch optical waveguide 12 is
The other optical signal which is incident on the input end of the branch optical waveguide 13 via the optical waveguide 22a, the optical frequency shifter 14b, and the optical waveguide 22b and which is distributed is the optical waveguide 23, the optical frequency shifter 14a, and the optical waveguide 24. It is incident on the input end of the branch optical waveguide 15 via.

The optical control type transmission phased array antenna of the second embodiment configured as described above operates as an up-converter for converting the frequency of the baseband signal into the frequency band of the microwave signal, and is the same as that of the first embodiment. Has the action and effect of.

Third Embodiment FIG. 3 is a block diagram of an optically controlled transmission phased array antenna according to a third embodiment of the present invention. In FIG. 2, the same parts as those in FIG. is doing.

The optically controlled phased array antenna of the third embodiment differs from the optically controlled phased array antenna of the first embodiment of FIG. 1 in the following points. That is, instead of the laser diode 1, the branch optical waveguide 12, and the optical frequency shifter 14 of FIG. 1, laser diodes 1a, 1b and an optical frequency control device 90 are provided, each power amplifier 7a to 7d and each antenna 8a. 8d to 8d, frequency converters 33a to 33d are provided, and the baseband signal output from the baseband signal generator 31 is divided into 4 by the distributor 37, and each of the divided signals is converted into a frequency converter. This is input to 34a to 34d.

In the optically controlled transmission phased array antenna configured as described above, the optical frequency control device 90, the frequency difference between the optical signals output from each laser diode 1a and 1b matches the frequency of the transmitted microwave signal. Thus, the laser diodes 1a and 1b are controlled. Laser diode 1a
The coherent optical signal output from the dielectric substrate 10
It is input to the branch optical waveguide 13 via the 0 input end 11a and the optical waveguide 22b. On the other hand, the coherent optical signal output from the laser diode 1b is input to the branch optical waveguide 15 via the input end 11b on the dielectric substrate 100 and the optical waveguide 24.

Further, the baseband signal output from the baseband signal generator 31 is divided into four by the distributor 37, and then each distributed baseband signal is input to the frequency converters 34a to 34d. The frequency converters 34a to 34d are respectively photoelectric converters.
The frequency of the microwave signal input from 6a to 6d via the power amplifiers 7a to 7d is shifted by the frequency of the baseband signal, that is, the baseband signal is frequency-converted into the frequency band of the microwave signal. , Antenna 8a
To 8d. As a result, the microwave signal including the information of the baseband signal is radiated into space from the antennas 8a to 8d.

The optically controlled phased array antenna of the third embodiment configured as described above operates as an up-converter that frequency-converts into a frequency band of a bake band signal microwave signal, and outputs the same signal as in the first embodiment. Have an effect.

Fourth Embodiment FIG. 4 is a block diagram of an optically controlled reception phased array antenna according to a fourth embodiment of the present invention. In FIG. 4, the same elements as those in FIGS. 1 to 3 are the same. The symbol is attached.

The optically controlled reception phased array antenna of the fourth embodiment differs from the optically controlled transmission phased array antenna of the first embodiment of FIG. 1 in that microwave signals received by antennas 32a to 32d are received. Low noise amplifier 35a
Through 35d, input to the frequency converters 34a to 34d provided in the subsequent stage of the power amplifiers 7a to 7d, the signals output from the frequency converters 34a to 34d are combined by the combiner 35 to form a baseband signal. And a microwave signal for outputting to the optical frequency shifter 14 a microwave signal having the same frequency as the received microwave signal instead of the transmitter 2 in FIG. That is, the generator 30 is provided.

In the optically controlled phased array antenna of the fourth embodiment configured as described above, the microwave signal including the information of the baseband signal transmitted from the partner station is transmitted to the antenna.
After being received by 32a to 32d, they are input to the frequency converters 34a to 34d via the low noise amplifiers 33a to 33d. The frequency converters 34a to 34d respectively frequency-convert the microwave signal containing the information of the baseband signal by the frequency of the microwave signal input from the photoelectric converters 6a to 6d via the power amplifiers 7a to 7d. Output to the combiner 35. Combiner
35 combines the input signals and outputs them as a baseband signal to the receiving device 36.

Therefore, the optically controlled phased array antenna according to the fourth embodiment operates as a down converter that frequency-converts the microwave signal modulated with the baseband signal into the frequency band of the baseband signal. Here, the antennas 32a to 3
The control of the receiving beam direction of the 2d array antenna is
This is performed by the direction control device 3 in the same manner as the transmission phased array antenna of the first to third embodiments.

Fifth Embodiment FIG. 5 is a block diagram of an optically controlled reception phased array antenna according to a fifth embodiment of the present invention. In FIG. 5, the same elements as those in FIGS. 1 to 3 are the same. The symbol is attached.

The optically controlled reception phased array antenna of the fifth embodiment differs from the optically controlled transmission phased array antenna of the third embodiment of FIG. 3 in that the microwave signals received by the antennas 32a to 32d are different from each other. Low noise amplifier 35a
Through 35d, input to the frequency converters 34a to 34d provided in the subsequent stage of the power amplifiers 7a to 7d, the signals output from the frequency converters 34a to 34d are combined by the combiner 35 to form a baseband signal. As a result, the optical frequency control device 90 causes the laser so that the frequency difference between the optical signals output from the laser diodes 1a and 1b matches the frequency of the received microwave signal. The purpose is to control the diodes 1a and 1b.

In the optically controlled phased array antenna of the fifth embodiment configured as described above, the microwave signal including the information of the baseband signal transmitted from the partner station is transmitted to the antenna.
After being received by 32a to 32d, they are input to the frequency converters 34a to 34d via the low noise amplifiers 33a to 33d. The frequency converters 34a to 34d respectively frequency-convert the microwave signal containing the information of the baseband signal by the frequency of the microwave signal input from the photoelectric converters 6a to 6d via the power amplifiers 7a to 7d. Output to the combiner 35. Combiner
35 combines the input signals and outputs them as a baseband signal to the receiving device 36.

Therefore, the optically controlled phased array antenna of the fifth embodiment operates as a down converter that frequency-converts the microwave signal modulated by the baseband signal into the frequency band of the baseband signal. Here, the antennas 32a to 3
The control of the receiving beam direction of the 2d array antenna is
This is performed by the direction control device 3 in the same manner as the transmission phased array antenna of the first to third embodiments.

[Effect of the Invention] As described in detail above, according to the present invention, in the optically controlled phased array antenna, the voltage generation means (4) for generating a DC voltage proportional to the beam deviation angle of the input phased array antenna. And a plurality of first optical signals output from the second distribution means (13) to the direct current voltage output from the voltage generation means (4), respectively, of the plurality of antennas (8a-8d). Based on the arrangement relationship, the plurality of transmission radio signals transmitted from the plurality of antennas (8a-8d) are phase-shifted by respective phase shift amounts proportional to each other by a plurality of predetermined proportional coefficients so as to be radiated in phase. Multiple phase shifting means (16a
-16d) and. Therefore, compared to the case of using a plurality of variable voltage sources (4a-4d) as in the conventional example, the circuit can be simplified and reduced in size and weight, and thus the entire phased array antenna including the circuit can be obtained. Small
The weight can be reduced. Further, since the beam direction can be controlled only by the DC voltage, there is an advantage that the control of the beam direction is simpler than that of the conventional example. These effects increase as the number of antenna elements increases.

Therefore, the optically controlled phased array antenna of the present invention can be applied to a mobile or satellite mounted phased array antenna.

[Brief description of drawings]

1 to 3 are block diagrams of an optically controlled transmission phased array antenna according to first to third embodiments of the present invention, and FIGS. 4 and 5 show fourth and fifth embodiments of the present invention. 6 is a block diagram of an optical control type reception phased array antenna which is an embodiment, FIG. 6 (A) is a perspective view showing a basic configuration of an optical phase shifter 16 used in FIGS. 1 to 5, and FIG. 4) used in FIGS. 1 to 5
FIG. 7 is a plan view showing the configuration of each of the optical phase shifters 16a to 16d, and FIG. 7 is a block diagram of a conventional optically controlled transmission phased array antenna. 1 ... Laser diode, 2 ... Transmitter, 3 ... Direction control device, 4,5 ... Variable voltage source 6a to 6d ... Photoelectric converter, 7a to 7d ... Power amplifier, 8a to 8d ... Antenna , 12,13,15 ...... Branch optical waveguide, 14 ...... Optical frequency shifter, 16a to 16d ...... Optical phase shifter, 18a to 18d ...... Multiplexing optical waveguide, 21 to 24,25a to 25d, 26a to 26d , 27a to 27d, 28a to 2
8d, 29a to 29d ... Optical waveguide, 80 ... Input device, 100 ... Dielectric substrate.

Front Page Continuation (72) Inventor, Koji Yasukawa, Kyoto, Soraku-gun, Seika-cho, Osamu Osamu, Osamu, Mihiratani No.5

Claims (1)

[Claims] 1. A phased array antenna comprising a plurality of antennas (8a-8d), wherein optical signal generating means (1) for generating coherent optical signals.
A first distribution means (12) for distributing an optical signal output from the optical signal generation means (1) into two optical signals, and one of the first output means (12) output from the first distribution means (12). Second distribution means (13) for distributing an optical signal into a plurality of first optical signals
A voltage generating means (4) for generating and outputting a DC voltage proportional to the beam deviation angle of the phased array antenna input thereto; and a plurality of first distribution means (13) for outputting from the second distributing means (13). Of the plurality of antennas (8a-8d) for the DC voltage output from the voltage generating means (4).
Phase shift amounts proportional to the phase shift amounts proportional to the plurality of predetermined proportional factors so that the plurality of transmission radio signals transmitted from the plurality of antennas (8a-8d) are radiated in phase based on the arrangement relationship of A plurality of phase shifting means (16a-16d) and a shifting means (14, 16d) for shifting the frequency of the other optical signal output from the first distributing means (12) by the frequency of the input transmission radio signal. 14a), a third distributing means (15) for distributing the optical signal output from the shift means (14, 14a) to the plurality of second optical signals, and the plurality of phase shifting means (16a- Each first output from 16d)
A plurality of multiplexing means (18a-18d) for respectively multiplexing the second optical signal output from the third distributing means (15) and the plurality of multiplexing means (18a). -18d) and a plurality of photoelectric conversion means (6a-6d) for detecting a plurality of optical signals and outputting a plurality of transmission radio signals to the plurality of antennas (8a-8d), respectively. , The plurality of transmission radio signals output from the plurality of photoelectric conversion means (6a-6d) are radiated from the plurality of antennas (8a-8d) at the beam deviation angle of the input phased array antenna. The feature is an optically controlled phased array antenna.