JP3204084B2 - Moving object identification device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to a transponder which moves when a transponder attached to a moving body such as a person, a car, a train, or the like passes near a fixed interrogator. The present invention relates to a mobile object identification device in which an interrogator identifies in a non-contact manner and exchanges information between an interrogator and a transponder.

[0002]

2. Description of the Related Art As a conventional moving object identification device, for example, a method described in Japanese Patent Application Laid-Open No. 1-182778 is known. Hereinafter, a conventional method will be described with reference to the drawings.

FIG. 14 is a conceptual diagram of a conventional moving object identification device. FIG. 15 shows the interrogator 702 and the responder 7 in FIG.
It is a timing chart which shows passage of time of the communication state of 01a, 701b.

In FIG. 14, an interrogator 702 continuously or intermittently transmits a communication start request signal R0 (FIG. 15). When the transponder 701a enters a communication area 703, the transponder 701a transmits the communication start request signal R0. Signal R0 (FIG. 15) is received at time t1, and response signal A0 (FIG. 15) is transmitted to interrogator 702 to start communication. The interrogator 702 transmits a communication end request signal RN (FIG. 15) when terminating or temporarily suspending communication with the responder 701a. The transponder 701a that has received the communication end request signal RN (FIG. 15) at time ts suspends the communication operation for a fixed time Δt. At this time, if another transponder 701b that has not performed the communication operation immediately before has newly entered the communication area 703, the transponder 701b transmits the reception confirmation signal A0,
The communication operation with the interrogator 702 is started. Therefore, unless the two transponders 701a and 701b enter the communication area 703 at exactly the same time, the two mobile stations 701a and 701b
a and 701b do not perform the transmission operation at the same time.

[0005]

The above-mentioned conventional mobile unit identification apparatus can communicate when two mobile stations do not enter the communication area at the same time, but two mobile stations enter the communication area at the same time. When the mobile station enters, or when three or more mobile stations exist in the communication area, communication cannot be performed because the reception confirmation signal A0 collides. Further, in the above-described conventional configuration, it is necessary that the interrogator and the transponder be communication devices that individually transmit and receive, but one of the transmitted carriers (for example, the carrier of the interrogator) is used and the other is used. It is difficult to realize such a configuration in which communication is performed using a reflection modulation operation (for example, a reflection modulation operation on the transponder side).

[0006] The present invention is to solve the above problems,
Even a simple communication device using intermittent, reflection and absorption of a carrier wave is intended to realize communication without interference with an interrogator and one of a plurality of transponders in a communication area. .

[0007]

In order to achieve the above object, according to the present invention, a carrier signal control transmitting means of an interrogator alternately transmits a periodically continuous carrier and a synchronization signal for stopping the carrier for a predetermined time. By this means, the synchronization signal detecting means of the transponder detects the part of the synchronization signal, and the modulation reflection means sequentially transmits the communication data by the modulation reflection during the continuation of the carrier wave after the synchronization signal, and periodically transmits the synchronization signal. The other transponders do not transmit the communication request signal or the communication data because the other transponders detect, and after the communication with the specific transponder is completed, the carrier signal control transmission means of the interrogator transmits the continuous carrier wave. If the synchronization signal is not detected for more than a predetermined time by the synchronization signal detection means, the transponder further performs detection until a time interval set at random by the random time generation means, In the transponders that generated the shortest random time among the transponders, the synchronization signal was not detected, the carrier was determined to be continuous, the communication request signal was transmitted, and after receiving the communication request signal, the interrogator transmitted the carrier signal control. The means is configured to alternately transmit a periodically continuous carrier and a synchronization signal.

According to the present invention, even in a simple communication apparatus using intermittent, reflection, and absorption of a carrier wave, communication without interference between the interrogator and one of the plurality of transponders in the communication area. Can be realized.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is characterized in that the interrogator has a communication determination control means for determining the presence or absence of a reflected radio wave from a transponder, and the communication determination control means has a communication area in the communication area. wherein a cyclically continuous carrier if a particular one transponder is determined that the responder raises an existing communication request signal is permitted to transmit the communication data transportable
A carrier that sends out a synchronous signal for stopping the transmission for a certain time alternately, and sends out only a continuous carrier signal in a standby state in which the communication determination control means determines that the transponder has not sent a communication request signal. A signal control transmitting unit, wherein the transponder includes a synchronous signal detecting unit that detects a synchronous signal transmitted from the interrogator, a random time generating unit that randomly sets a time interval, and a pre-synchronizing signal detecting unit. Gating period determination control means for determining that the carrier is continuous after a time interval set at random by the random time generation means when the synchronization signal is not detected for a predetermined time or more, and immediately determining that the carrier wave is disconnected when the synchronization signal is detected. When,
An information storage means for storing communication data; and a communication request signal and a sequential modulation reflection means for modulating communication data determined when reflecting the carrier signal transmitted from the interrogator. Entering the area, when the gating period determination control means determines that the carrier wave is continuous, immediately after the sequential modulation reflection means sends out the determined communication request signal.
After the synchronization signal detection means detects the synchronization signal and determines that the carrier is intermittent, the sequential modulation reflection means sends communication data during the carrier wave continuation, and before the transponder sends a predetermined communication request signal. When the gating cycle determination control means detects a synchronization signal and determines that the carrier is gating, the sequential modulation and reflection means does not transmit the communication request signal until the gating cycle means determines that the carrier is continuous. In the case where the synchronization signal detecting means does not detect the synchronization signal for a certain period of time or more, the carrier signal is determined to be continuous after a randomly set time. Differently, the transponder which transmitted the communication request signal earliest transmits the communication data without collision of the communication request signal, and the carrier signal control transmitting means of the interrogator. For delivering intermittent carrier wave,
The other transponders do not transmit the communication data until the next determination is made that the carrier wave is continuous, so that the transponder has an effect of being able to communicate without interfering with one of the transponders in the communication area.

According to a second aspect of the present invention, the stop of the carrier wave for a predetermined time is used as a synchronization signal, and the storage contents can be changed when the power is on as the information storage means of the transponder and stored when the power is off. Carrier wave reception having a non-volatile storage means for holding the contents, and rectifying radio waves radiated from the interrogator in the transponder and serving as a power source for the information storage means, the sequential modulation reflection means, and the intermittent period determination control means. It has a rectifier means, and when the sequential modulation reflection means of the transponder has started transmission of communication data by modulation reflection, the information storage means has already transmitted just before the transmission of the carrier wave from the interrogator is stopped. The address of the communication data in the memory is held in the non-volatile storage means, and transmission of the communication data which has not been transmitted is restarted when the carrier wave is transmitted again. Since the non-volatile storage means is used as the storage means, even when rectifying the carrier from the interrogator and using the power supply of the transponder, the address of the transmitted communication data in the memory immediately before the stop of the carrier is stored in the information storage unit. The other interrogator is reset to the initial state at this time to hold it, whereas the carrier wave of the interrogator is rectified by re-rectifying the Has the effect that one of the transponders used for communication can continue communication.

[0011] In the invention according to claim 3, the interrogator includes:
Correctness judgment means for judging the correctness of the output of the reception demodulation means, and when the correctness judgment means judges that the communication data was erroneously received, the non-volatile storage means of the transponder stores the communication data on the memory. A second periodic intermittent unit for transmitting a carrier wave continuous with the synchronizing signal in a cycle shorter than a cycle for updating the address, wherein the non-volatile information means of the transponder updates the address of the communication data on the memory; When there is no communication data, the sequential reflection means retransmits the communication data, and the interrogator has correct / error determining means for determining whether the communication data received is correct, and it has been determined that the communication data was erroneously received. Occasionally, the periodic interrupting means interrupts the carrier in a short cycle, so the carrier stops before the address on the memory is held as the transmitted communication data in the non-volatile memory of the transponder, and again. Since transmitting is left address of already transmitted communication data held before the information storage unit when sent, has the effect of the communication data received incorrectly in interrogator can responder retransmits.

[0012]

[0013]

[0014]

[0015]

An embodiment of the present invention will be described below with reference to FIGS. (Embodiment 1) FIG. 1 is a block connection diagram of a moving object identification device according to a first embodiment of the present invention. In FIG. 1, 1
Reference numeral 01 denotes a fixedly installed interrogator. When the transponder 102 attached to a mobile object such as a person, a car, or a train passes nearby, the transponder 102 identifies the moving transponder 102 in a non-contact manner and responds. Exchange information with the device.

Numeral 110 denotes a carrier control transmitting means constituting the interrogator 101, which transmits a continuous carrier wave in a standby state where there is no transmission from the transponder 102, and communicates communication data with one specific transponder 102. Sometimes it sends out intermittent carriers. Reference numeral 111 denotes communication determination control means constituting the interrogator 101, which controls the carrier wave control transmission means 110 according to the demodulation state of the reception demodulation means 112. Reference numeral 113 denotes a transmission antenna constituting the interrogator 101, which transmits a carrier wave output from the carrier wave control transmitting means 110 to the transponder 102. On the other hand, reference numeral 114 denotes a receiving antenna constituting the interrogator 101, which receives a demodulation signal from the transponder 102,
Supply to 12. Note that the transmission antenna 113 and the reception antenna 114 may be configured as transmission / reception antennas by a general configuration.

In the carrier control transmitting means 110, 115 is a carrier signal generating means for generating a fixed carrier signal, and 116 is an output of the carrier signal generating means 115 as a synchronizing signal when communicating with one transponder 102. Periodic switching means 117 for stopping the carrier wave for a certain time with respect to a certain carrier signal; 117, a signal switching means for switching one of the output of the carrier signal generating means 115 and the output of the periodic gating means 116; The transmission power amplifier amplifies the output of the signal switching means 117.

On the other hand, reference numeral 120 denotes a sequential modulation reflection means constituting the transponder 102, which reflects the carrier signal transmitted from the interrogator 101 according to the conditions. Reference numeral 121 denotes a synchronization signal detecting unit included in the transponder 102, and detects a synchronization signal of the carrier signal transmitted from the interrogator 101. Reference numeral 122 denotes an intermittent cycle determination control unit which constitutes the transponder 102.
The continuity / intermittent of the carrier signal transmitted from 1 is determined.
Numeral 127 denotes a random time generating means which constitutes the transponder 102, and supplies a random time for the determination by the intermittent cycle determination control means 122. Reference numeral 123 denotes a transmitting / receiving antenna constituting the responder 102, which transmits / receives a signal to / from the interrogator 101.

In the sequential modulation reflecting means 124,
126 is an information storage means for storing communication data, 12
Reference numeral 5 denotes a modulating / reflecting means for modulating a carrier wave based on the communication data in the information storage means 126, and 124 outputs a modulated / reflected signal of the modulating / reflecting means 125 in a transmission mode described later, and is transmitted from the interrogator 101 in a receiving mode. And a signal switching unit for causing the synchronization signal detecting unit 121 to transmit the generated carrier signal.

FIG. 2 is a diagram showing the positional relationship between the transponder and the interrogator in the communication area. 2, 101 is an interrogator in FIG. 1, 102, 130, and 131 are transponders, and transponders 130 and 131 are transponders 102 in FIG.
Is equivalent to Reference numeral 104 denotes a communication area of the interrogator 101.

FIG. 3 is a diagram showing the timing of communication between the interrogator and the responder. In FIG. 3, (a) shows the interrogator 10
1 (b) shows the transmission timing of the carrier signal of FIG.
2, (c) shows the modulated reflected signal of the transponder 130, and (d) shows the time lapse of the modulated reflected signal of the transponder 131, and t1, t2, t3, t4, t5, t6, and t.
7, t8, t9, t10, t11, and t12 each represent time.

The operation of the moving object identification device configured as described above will be described below. First, when there is no transponder in the communication area, the interrogator 101 converts the continuous carrier signal generated by the carrier signal generation means 115 into the transmission power amplifier 11 through the signal switching means 117.
8 and then transmitted from the transmission antenna 113. Further, the interrogator 101 stops the carrier wave for a fixed time as a synchronization signal when communicating with one transponder.

At the time t1, the transponder 102 is placed in the communication area 140.
Enters, if the carrier does not stop until t2 after the predetermined time interval ton, the intermittent cycle determination control means 122 further waits for the randomly set time interval tr1 of the random time generation means 127. I do.

If the synchronization signal detecting means 121 does not detect the stop of the carrier by the time t3 after the time tr1, the gating cycle determination control means 122 determines that the carrier signal is continuous, sets the switching means 124 to the switching transmission mode, and sets the modulation mode. The reflection means 125 modulates and reflects a predetermined communication request.

If the synchronization signal detecting means 121 detects the stop of the carrier wave during the predetermined time interval ton or the random time interval tr1, the intermittent period determination control means 122 returns to the state after the predetermined time ton. Check that there is no stoppage of the carrier wave.

On the other hand, the interrogator 101 demodulates the modulated reflected signal from the transponder 102 by the reception / demodulation means 112 and immediately switches the switching means 117 when the communication determination control means 111 determines that the signal is a predetermined communication request signal. The carrier signal (carrier wave transmission time interval ton, carrier wave stop time interval toff) that is periodically intermittently transmitted by the switching periodic intermittent means 116 is transmitted.

After transmitting the communication request signal, the transponder 102 switches the switching means 124 to the switching reception mode, and after the synchronous signal detecting means detects the stop of the carrier wave at toff, switches the switching means 124 during the continuation of the carrier wave to the transmission mode. The modulation reflection means 125 modulates and reflects the carrier with the communication data of the information storage means 126. After a predetermined time ton, the modulation reflection is interrupted, the switching means 124 is set to the reception mode, and after the synchronization signal detection means 121 detects the carrier stop again, the switching means 124 is switched to the transmission mode, and the communication data is modulated and reflected again. , And similarly continues until t4 when all the communication data of the transponder 102 has been transmitted.

The transponder 130 is provided between the time t1 and the time t5.
And 131 enter the communication area 140, the synchronization signal detecting means 12 of the transponders 130 and 131 respectively.
Since 1 has detected the stop of the carrier wave, the communication of the transponder 102 is completed, and the data communication by the modulation reflection is not performed until t5 after the last stop of the carrier wave.

The time interval ton determined from the time t5 and the time randomly set by the random time generation means 127, the transponder 130 is tr2, and the transponder 131 is tr3
It waits until (tr2> tr3). Transponder 131
Sends a communication request signal at t7 because the waiting time set at random is short, and thereafter transmits data to the interrogator.

The transponder 130 detects the stop of the carrier wave because the waiting time set at random is long, and thereafter does not transmit the data until the transponder 131 finishes transmitting all the communication data at time t8.

If the stop of the carrier is not detected for the time interval ton determined from the time t9 and the time randomly set by the random time generating means 127, the time t
11, a communication request signal is sent, and then data is sent when a carrier wave is being sent next.

In the above description, the synchronizing signal is the stop period of the carrier, but the carrier may be modulated in a specific pattern (for example, a PN code).

As described above, according to the mobile unit identification apparatus of the present embodiment, the interrogator transmits a continuous carrier wave when the interrogator is in the standby state where there is no transmission from the transponder, and communicates with one specific transponder and the communication data. When the communication is performed, the intermittent carrier is transmitted. When the intermittent carrier is transmitted, the transponder is communicating with another specific transponder.Therefore, the transponder does not transmit the communication data, and the transponder does not transmit random data even when a continuous carrier is detected. Since the communication data is transmitted after waiting for a time, there is no data collision in the plurality of transponders, and the communication with the interrogator can be performed.

(Embodiment 2) FIG. 4 is a block connection diagram of a moving object identification apparatus according to a second embodiment of the present invention.

FIG. 4 differs from the configuration of FIG.
First, with respect to the interrogator 101, a correct / incorrect judgment unit 20 for judging an error in demodulated data from the output of the reception demodulation unit 112.
1 and a periodic intermittent means 11 of FIG.
A first periodic intermittent means 202 and a second periodic intermittent means 203 having two types of intermittent properties in place of 6;
The switching means 204 controls the carrier signal generation means 115,
First periodic intermittent means 202, second periodic intermittent means 2
03 is selected based on the output of the communication determination control means 111. Transponder 1
In No. 02, a carrier receiving rectifying unit 207 which receives a carrier wave by a receiving antenna 205, rectifies the carrier wave by a carrier rectifying unit 206 and uses the rectified signal as a power source, and a non-volatile storage unit 208 which stores a communication request signal is provided. It is a point.

FIG. 5 is a diagram showing the timing of communication between the interrogator 101 and the responder 102. In FIG. 5, (a)
Is the transmission timing of the carrier signal of the interrogator 101,
(B) shows the time lapse of the modulated reflected signal of the transponder 102, and t1, t2, t3, t4, t5, t6, t7,
t8, t9, and t10 represent time.

The operation of the moving object identification device configured as described above will be described below. First, when the transponder 102 does not exist in the communication area, the interrogator 101 power-amplifies the continuous carrier signal generated by the carrier signal generation unit 115 by the transmission power amplifier 118,
Transmitted from the transmitting antenna 113.

The transponder 102 is a carrier wave receiving rectifier 207.
The receiving antenna 205 receives the carrier transmitted from the transmitting antenna 113 and rectifies the carrier by the carrier rectifier 207.

The rectified signal is used as a power source to operate the sequentially modulating / reflecting means 120, the intermittent cycle determination control means 122, and the random time generation means 127 inside the transponder 102.

The transponder 102 enters the communication area with the interrogator 101 at time t1 and when a carrier signal is present, the carrier reception rectifier 207 rectifies the carrier signal and becomes a power source. Modulation reflection means 120, intermittent cycle determination control means 122, random time generation means 127
Operation starts.

If there is no stoppage of the carrier until time t1 after a predetermined time interval ton, the intermittent cycle determination control means 122 waits for a time tr1 set by the random time generation means 127 at random.

If the carrier does not stop by the time t3 after the time tr1, the transponder 102 modulates the carrier from the interrogator 101 by the modulation reflection means 127 to modulate the communication request signal stored in the nonvolatile storage means 208. Make a reflection.

After receiving the communication request signal, the interrogator 101
The carrier is continuously transmitted at the time interval ton, and the time interval tof
The first periodic intermittent means 201 for stopping the carrier at f
After stopping the carrier wave at the time interval toff, the carrier wave transmission is started at time t4.

The transponder 102 includes a nonvolatile storage unit 208
The carrier reflected from the interrogator 101 is modulated and reflected by the modulation reflection means 125 to transmit the communication data stored in the communication data. The interrogator 101 receives the reflected radio wave from the transponder 102 and
14 and the correct / incorrect judgment means 201 judges the demodulated data of the reception demodulation means 112. If this determination result is correct, the first periodic intermittent means 202 sets the time interval toff
To stop the carrier.

This time interval ton is stored in the nonvolatile storage means 2
Since 08 is longer than the time for updating and storing the address of the internal transmitted communication data in the memory, the carrier stops at t5 after updating the address in the memory.

On the other hand, when the correct / incorrect judgment means 201 judges that there is an error in the demodulated data, the second periodic continuation means 20 for stopping the carrier at a time interval tng shorter than ton.
3 stops the carrier at the time interval tng. Since this time interval tng is shorter than the time when the nonvolatile storage unit 208 updates the address of the internally transmitted communication data in the memory, the data is retransmitted at the next start of the carrier wave transmission. .

From time t6, transponder 102 transmits data by modulation reflection, but if an error in data is detected by interrogator 101, the carrier stops at time t7 after tng.

For this reason, before the address of the transmitted communication data in the memory is updated in the nonvolatile storage means 208, the output of the carrier wave reception rectification means 207 is turned off, and the modulation reflection means 120, the intermittent period judgment control means 122, the operation of the random time generation means 127 stops.

Next, at time t8, when the carrier is transmitted again, the transponder transfers the same data as the data started to be transferred at time t6. When data is sent without error,
At a time t9 after the time interval ton by the first periodic intermittent means 202, the carrier wave from the interrogator 101 is updated after the address in the memory of the communication data transmitted by the transponder 102 is updated by the nonvolatile storage means 208. The operation stops, and transmission of all communication data ends at t10.

In the above description, the synchronizing signal is the stop period of the carrier, but the carrier may be modulated in a specific pattern (for example, PN code).

As described above, according to the moving object identification device of the present embodiment, the transponder 102
07, the carrier is rectified and used as a power source, so that when communicating with one specific transponder 102, the other transponders are always reset due to the interruption of the carrier, so that no communication is performed, and When the correct / wrong determining means 201 of the interrogator 101 determines that the communication data has been erroneously received, the first and second periodic intermittent means 202, 20
3 performs the intermittent operation of the carrier wave in a short cycle.
The carrier wave stops before the address on the memory is held as the transmitted communication data in the non-volatile storage means 208, and when the carrier wave is transmitted again, the address of the transmitted communication data previously held remains in the information storage unit. The interrogator 10
1 enables the transponder to retransmit the erroneously received communication data.

(Embodiment 3) FIG. 6 is a block diagram showing a mobile unit identification apparatus according to a third embodiment of the present invention.

FIG. 6 differs from the configuration of FIG.
The interrogator 101 is different from the interrogator 101 in that the correctness / incorrectness determination means 201 of FIG. 4 is provided, and the result of the correctness / incorrectness determination is provided by a modulation means 304 for modulating the carrier with the communication slot number transmitted by the transponder 102. On the other hand, the transponder 102 is provided with a communication slot selection control means 302 for randomly selecting a communication slot, and the interrogator 101
Demodulating means 30 for demodulating the result of correct / incorrect judgment sent from
3 is provided.

FIG. 7 is a diagram showing the timing of communication between the interrogator and the transponder. In FIG. 7, (a) shows the transmission timing of the carrier of the interrogator, (b) shows the frame and communication slot, (c) shows the transmission timing of the interrogator, and (d) shows the timing of the transmission in the communication area of the interrogator. (E) is the transmission timing of the second transponder in the communication area of the interrogator, and (f) is the transmission timing of the third transponder in the communication area of the interrogator. Yes, 310, 311,
312 is a frame, s1, s2, s3, s4, s5, s
6 is a communication slot, 313, 314 and 315 are communication slots transmitted by the interrogator, 316 is a communication slot transmitted by the first transponder, 317 and 318 are slots transmitted by the second transponder, 319 and 320 are This is a communication slot transmitted by the third transponder.

The operation of the moving object identification device configured as described above will be described below.

First, in the interrogator 101, the carrier signal control means 110 repeats the transmission and the stop of the carrier at a constant period shown in FIG.

As shown in FIG. 2, when the first transponder 102 enters the communication area of the interrogator 101, the transponder 102 synchronizes the carrier stop portion with the received signal by the synchronization signal detecting means 121. The communication slot selection control means 302 detects the signal as a signal and randomly selects any one of the first five communication slots among the six communication slots existing at equal intervals in the frame 310 starting from the rising edge of the carrier wave, and (c) In the selected communication slot s2 indicated by 316, the modulation reflection means 120 sequentially sends out the data of the information storage means 126 by modulation reflection.

The communication data from the first responder is interrogator 1
01 is demodulated by the reception demodulation means 112 of FIG.
At 01, it is determined whether or not there is an error in the data. 31 of (c)
In the communication slot s6 shown in FIG. 3, the result of the right / wrong judgment is modulated by the modulating means 304 together with the communication slot number transmitted by the transponder, and sent out. The result is demodulated, and if there is no error, the data transmission from the first transponder ends.

In the communication area of the interrogator, as shown in FIG.
When the transponder 130 and the third transponder 131 enter, the transponders respectively detect the stop of the carrier in the received signal as the synchronization signal by the synchronization signal detecting means 121, and the frame 311 starting from the rising edge of the carrier. The communication slot selection control means 302 randomly selects any one of the first five communication slots among the six communication slots existing at equal intervals, and selects the selected communication slots 317 in (e) and 319 in (f). The modulation reflection means 120 sequentially transmits the data of the information storage means 126 by modulation reflection in the slot.

At this time, since the second transponder and the third transponder select the same communication slot s2, collision of communication data occurs, and the demodulated data in the interrogator is erroneous by the correct / incorrect judgment means 201. Is determined. For this reason, 314 of (c)
The result of the right / wrong judgment which is modulated and transmitted from the interrogator in the slot s6 shown in FIG. 4 is demodulated by the transponder and the communication slot selecting means 302 retransmits data in the next frame 312.

In the frame 312, as a result of the communication slot selection control means of the second transponder selecting a communication slot at random, the communication slot s4 indicated by 318 in (e) is selected, and the third transponder (f) is selected. Since the communication slot s2 shown in (320) is selected, no collision of communication data occurs, the correctness judgment means of the interrogator judges that there is no error, and the judgment result is transmitted in the communication slot s6 shown in 315 of (c). Then, it is demodulated by the transponder, and the data transmission from the second and third transponders ends.

In the above description, the number of communication slots is six, but any number of two or more may be used. Further, although the synchronization signal is used as the carrier stop section, the carrier may be modulated in a specific pattern (for example, a PN code).

As described above, according to the mobile unit identification apparatus of the present embodiment, the timing of data transmission from transponder 102 to interrogator 101 is defined as a communication slot, and transponder 102 randomly selects a communication slot. Therefore, even when a plurality of transponders exist in the communication area of the interrogator 101, the probability of occurrence of transmission data collision decreases. Further, even when the transmission data collides, the interrogator 101 returns the reception correct / incorrect judgment result to the transponder 102, so that reliable communication with the interrogator 101 is possible.

(Embodiment 4) FIG. 8 is a block diagram showing a mobile unit identification apparatus according to a fourth embodiment of the present invention.

FIG. 8 differs from FIG. 6 in that
A communication request signal slot selection control unit 401 for randomly selecting a communication request signal slot is provided, and a communication data transmission control unit 402 for transmitting data in a communication data slot corresponding to the communication request signal slot is newly provided. .

FIG. 9 is a diagram showing the timing of communication between the interrogator and the transponder. In FIG. 9, (a) is the transmission timing of the carrier wave of the interrogator, (b) is the frame and communication slot, (c) is the transmission timing of the interrogator, and (d) is the first in the communication area of the interrogator. (E) is the transmission timing of the second transponder in the communication area of the interrogator, and 410 is the frame, c1, c2,
c3, c4, c5, c6 are communication request signal slots, s
1, s2, s3 are communication data slots, 411, 41
Reference numerals 2 and 413 denote timings at which the interrogator sends the correct / incorrect judgment result of the communication request signal, and reference numerals 414 and 415 denote timings at which the interrogator sends the correct / incorrect judgment result of the communication data.
7 is a timing at which the first transponder transmits a communication request signal, 418 is a timing at which the first transponder transmits communication data, 419 and 420 are timings at which the second transponder transmits a communication request signal, 421. Is the timing at which the second transponder sends communication data.

The operation of the moving object identification device configured as described above will be described below.

The interrogator 101 is provided with a carrier signal control unit 11.
0 repeats the transmission and the stop of the carrier at the timing of the constant cycle shown in FIG.

As shown in FIG. 2, when the first transponder 102 and the second transponder 130 enter the communication area of the interrogator 101, the transponder synchronizes the carrier stop portion with the received signal. The signal detection means 121 detects a synchronization signal,
Communication request signal slot selection control means 401 which is present at equal intervals in frame 410 starting from the rising of the carrier wave and corresponding to communication data slots s1, s2, and s3 from three communication request signal slots c1, c2, and c3, respectively.
Randomly selects a communication request signal slot, and the first transponder 102 selects the selected slot c indicated by 416 in (d).
In the first half of 2, the second transponder 130 transmits the communication request signal in the first half of the selected slot c2 indicated by 419 in FIG.

However, since the two signals collide at this time, the correct / incorrect judgment means 201 determines whether the received demodulated signal of the interrogator is correct.
Is determined to be an error. The result of this right / wrong judgment is the
4 and transmitted in the second half of slot c2.

Each of the transponders demodulates the result of the correct / incorrect judgment sent from the interrogator 101 by the demodulation means 303, and since there is an error, each of the communication request signal slot selection control means 401 again transmits the communication data slots s1, s2. , S3
The communication request signal slot selection control unit 401 randomly selects a slot from three communication request signal slots c4, c5, and c6, respectively.

The first responder 102 selects the slot c4 indicated by 417 in (d), and the second responder 130 selects (e) the slot c4.
And selects a slot c6 indicated by 420, and sends a communication request signal in the first half of each slot.

Since the communication request signal of the transponder is transmitted without collision, the true / false determination means 201 determines that the received demodulation signal of the interrogator 101 has been received without error and transmits the determination result to the transponder. I do.

In each of the transponders 102 and 130, the communication data transmission control means 402 transmits data in the communication data slot corresponding to the communication request signal slot.

The first transponder 102 performs transmission in slot s1 indicated by 418 in (d) corresponding to slot c4,
The second transponder 130 performs transmission at s3 indicated by 421 in (e) corresponding to slot c6.

The interrogator 101 receives and demodulates the communication data from the transponder, and sends the result of the right / wrong judgment to the transponder. If the transponder can transmit without error, the transmission is terminated. If an error exists, the same processing is performed again in the next frame.

When the communication request signal slot for the communication data slot is correctly received once, the communication determination control means 111 of the interrogator 101 receives a communication request for the communication data slot from another transponder after that. ,
Since the right / wrong judgment result is not returned to the transponder, the transmission slot is not allocated to two or more transponders.

In the above description, the number of communication data slots is three, but any number of two or more communication data slots may be used. The number of communication request signal slots is 6, but any number may be used as long as it is an integral multiple of the communication data slot. Further, although the synchronization signal is used as the carrier stop section, the carrier may be modulated in a specific pattern (for example, a PN code).

As described above, according to the mobile unit identification apparatus of the present embodiment, since the data length of the communication request signal is sufficiently shorter than the data length of the communication data, the communication request is an integral multiple of the communication data slot. A signal slot is provided, and even if a communication request signal transmitted by the transponder collides, a plurality of communication requests can be made, and communication slots can be efficiently allocated.

(Embodiment 5) FIG. 10 is a block diagram showing a moving object identification apparatus according to a fifth embodiment of the present invention.

10 is different from the configuration of FIG. 1 in that the interrogator 1 does not include the signal switching means 117 and the communication determination control means 111 and newly adds
12, an interrogator spreading code generating means 501 for generating a spreading code for performing spectrum despreading is provided. On the other hand, the transponder 102 is different from the transponder 102 in that a transponder spread code generator 502 for newly generating a spread code is provided in place of the random time generator 127 of FIG.

FIG. 11 shows an example of generation of spreading codes of the interrogator and the transponder. In FIG. 11, (a) shows the transmission timing of the carrier wave of the interrogator, (b) shows the sequence of the spreading code generated by the interrogator spreading code generation means, and (c) shows the first sequence.
(D) is a sequence of spread codes generated by the transponder spread code generating means of the second transponder, F1, F2, F3, F
4, F5 is a frame number.

The operation of the moving object identification device configured as described above will be described below.

First, in the interrogator 101, the carrier signal control means 110 repeats the transmission and the stop of the carrier at the timing of a constant cycle shown in FIG. As shown in FIG.
In the communication area of the interrogator 101, the first responder 102 and the second
When the transponder 130 has entered the transponder 130, the transponder detects the received carrier stop portion as the synchronization signal detected by the synchronization signal detection means 121, and the intermittent period determination control means 122 starts the rising of the restart of the carrier wave transmission. In the spreading code generating means 502, the first transponder 102 starts generating the spreading code of the sequence PN2 shown in FIG.
Numeral 30 starts generating a spreading code of the sequence PN5 shown in FIG.

The modulation reflection means 125 is provided for the information storage means 12.
After performing phase modulation on the carrier with the communication data of No. 6, spread spectrum modulation is performed by applying phase modulation with the spread code.

Interrogator spread code generating means 5 of interrogator 101
In the case of 01, the periodic intermittent means 116 stops the carrier wave, the spreading code is sequentially changed for each frame starting from the rising edge of the restart of the carrier wave transmission, and the receiving / demodulating means 112 performs spectrum despreading.

In frames F1, F3, and F4, interrogator spreading code generation means 501 generates sequences PN1, PN3, and PN4, so that received modulated wave sequence PN2 of first transponder 102 and second transponder 130 modulated wave sequence PN5
Since there is no correlation with the data, the interrogator 101 does not receive data.

In frame F2, interrogator spreading code generating means 501 generates sequence PN2.
It matches the sequence PN2 of the 02 modulated wave. Also, interrogator spreading code generating means 501 and transponder spreading code generating means 502
Since the start point of the spreading code sequence by the synchronization signal due to the stop of the carrier coincides, if the interrogator 101 and the transponder are the same sequence in the frame, a correlation is obtained by despreading and data reception is performed.

On the other hand, in the second transponder 130, the sequence PN5
Is generated and the sequence is different from that of the interrogator 101, so that there is no correlation and no data reception is performed.

In frame F5, on the contrary, there is no correlation with the sequence PN2 of the first transponder 102, so that no reception is performed, and the correlation is obtained with the sequence PN5 of the second transponder 130. And data reception is performed.

In the above description, this is repeated assuming that the number of frames is 5, but any two or more frames may be used. Further, although the synchronization signal is used as the carrier stop section, the carrier may be modulated in a specific pattern (for example, a PN code).

As described above, according to the mobile object identification apparatus according to the present embodiment, a unique spreading code sequence is assigned to each transponder, and the interrogator 101 and the transponder 102 or 130 are synchronized with the synchronization signal by the synchronization signal, respectively. So that
Since the spectrum despreading can be easily performed, and the spread codes used in the plurality of transponders are different, the interrogator can read those data signals independently.

(Embodiment 6) FIG. 12 is a block diagram of an interrogator 101 of a moving object identification apparatus according to a sixth embodiment of the present invention.

In FIG. 12, reference numeral 117a designates an output of a carrier signal control / transmission means, which will be described later, and
01, 603, and 605, a signal switching unit that switches the reception output of the receiving antennas 602, 604, and 606 that receives a transmission signal from the transponder 102; and 607, a carrier that transmits a carrier. Signal control transmission means, 608 is a reception / demodulation means for receiving and demodulating a transmission signal from the transponder, 609 is a true / false determination means for judging an error in the reception data demodulated by the reception / demodulation means 608, and 610 is a function of the communication area. Signal switching means 1
Communication area switching means for controlling 17a and 117b.

FIG. 13 is a diagram showing a communication area obtained by switching the antenna of the interrogator. In FIG. 13, 621 and 6
Reference numerals 22 and 623 denote communication areas when the antenna is switched.

[0097] The operation of the moving object identification device configured as described above will be described below.

First, the transmitting antenna 60 is provided to the interrogator 101.
1, 603, 605 and receiving antennas 602, 604, 6
06, and the communication area determined by the directivity of each antenna 601 and 602 is 621, and the antenna 60
The communication area determined by the directivity of 3, 604 is 62
2. When the communication area determined by the directivity of the antennas 605 and 606 is 623, the communication area switching means 610 first switches the signal switching means 117a and 117b, selects the transmission antenna 601 and the reception antenna 602, and selects the communication area. Is set to 621.

The carrier signal control transmitting means 607 transmits the carrier wave, and the transponder transmits the communication request or the communication data by the modulation reflection.
Since there are two transponders 2 and 131, collision occurs in the communication data, and the output of the reception demodulation unit 608 determines whether the received data is erroneous.

Next, the communication area switching means selects the transmission antenna 603 and the reception antenna 604, and the communication area becomes 6
22. Since only one of the transponders 102 exists in this communication area, the communication data due to the modulation reflection from the transponder is demodulated by the reception demodulation means, and thereafter, it is determined by the correctness / incorrectness determination means that the data has been correctly received. Next, the communication area switching means selects the transmission antenna 605 and the reception antenna 604, and the communication area becomes 623. The transponder 13 is located in this area.
Since only one is present, the communication data due to the modulation reflection from the transponder is demodulated by the reception demodulation means, and then it is determined by the correctness determination means that it was correctly received.

In the above description, three sets of transmitting antennas and receiving antennas are used, but any of two or more sets may be used.

As described above, according to the mobile object identification apparatus of the present embodiment, since the interrogator has a plurality of transmitting / receiving antennas and switches between them, there is a plurality of transponders for one interrogator. Also, by switching to an antenna having a different directivity, one transponder without a communication area can be used, and as a result, data communication with a plurality of transponders becomes possible.

[0103]

According to the present invention, there is provided a mobile identification apparatus in which a transponder transmits and receives data by using a carrier wave transmitted by an interrogator. The transponder includes a plurality of transponders in a communication area of the received interrogator. In this case, there is an advantage that data can be communicated with each of them.

[Brief description of the drawings]

FIG. 1 is a block connection diagram of a moving object identification device according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a relationship between a transponder and an interrogator in a communication area according to the first embodiment of the present invention.

FIG. 3 is a diagram showing the timing of communication between the interrogator and the transponder according to the first embodiment of the present invention.

FIG. 4 is a block diagram of a moving object identification device according to a second embodiment of the present invention.

FIG. 5 is a diagram showing the timing of communication between an interrogator and a transponder according to a second embodiment of the present invention.

FIG. 6 is a block diagram of a moving object identification device according to a third embodiment of the present invention.

FIG. 7 is a diagram showing communication timing between an interrogator and a transponder according to a third embodiment of the present invention.

FIG. 8 is a block diagram of a moving object identification device according to a fourth embodiment of the present invention.

FIG. 9 is a diagram showing the timing of communication between the interrogator and the transponder according to the fourth embodiment of the present invention.

FIG. 10 is a block diagram of a moving object identification device according to a fifth embodiment of the present invention.

FIG. 11 is a diagram showing an example of generation of spreading codes of an interrogator and a transponder according to a fifth embodiment of the present invention.

FIG. 12 is a block diagram of a moving object identification device according to a sixth embodiment of the present invention.

FIG. 13 is a diagram showing a communication area by antenna switching of an interrogator according to a sixth embodiment of the present invention.

FIG. 14 is a conceptual diagram of a conventional moving object identification device.

FIG. 15 is a diagram showing communication timing of a conventional mobile unit identification device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 101 Interrogator 102 Transponder 110 Carrier signal control transmission means 111 Communication determination control means 112 Reception demodulation means 113 Transmission antenna 114 Reception antenna 120 Sequential modulation reflection means 121 Synchronization signal detection means 122 Intermittent period determination control means 123 Transmission antenna 127 Random time generation Means 201 Correctness judgment means 207 Carrier reception rectification means 208 Nonvolatile storage means 302 Communication slot selection control means 303 Demodulation means 401 Communication request signal slot selection control means 402 Communication data transmission control means 501 Interrogator spread code generation means 502 Transponder spread code Generation means 610 Communication area switching means

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Naoki Adachi 1006 Kazuma Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-3-82979 (JP, A) JP-A-7 JP-A-140236 (JP, A) JP-A-6-201821 (JP, A) JP-A-50-109695 (JP, A) JP-A-8-21874 (JP, A) JP-A-6-181449 (JP, A) JP-A-7-159527 (JP, A) JP-A-8-68854 (JP, A) JP-A-63-134978 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H04B 7/24-7/26 H04Q 7/00-7/38 H04B 1/59 H04B 5/02

Claims (3)

(57) [Claims] 1. An interrogator, a communication determination control means for determining the presence or absence of a reflected radio wave from a transponder, and the communication determination control means determines that the transponder is present in a communication area and has transmitted a communication request signal. When one specific transponder is allowed to transmit communication data, the transponder periodically sends alternately a continuous carrier wave and a synchronization signal for stopping the carrier wave for a certain period of time. A carrier signal control transmitting means for transmitting only a continuous carrier signal in a standby state in which it is determined that the communication request signal has not been transmitted, and detecting, in the transponder, a synchronization signal transmitted from the interrogator; Synchronizing signal detecting means, random time generating means for randomly setting a time interval, and the random time when the pre-synchronizing signal detecting means does not detect a synchronizing signal for a predetermined time or more. Gating period determination control means for determining carrier continuity after a time interval set at random by the generation means and immediately determining that the carrier wave is gating when a synchronization signal is detected; information storage means for storing communication data; A communication request signal determined when reflecting the carrier signal sent from the device and a sequential modulation reflection means for modulating the communication data, the transponder enters a communication area, and the intermittent cycle determination control means includes When it is determined that the carrier wave is continuous, immediately after the sequential modulation / reflection unit sends out a predetermined communication request signal, the synchronization signal detection unit detects the synchronization signal and determines that the carrier wave is intermittent. Communication data is sent during the period, and before the transponder sends a predetermined communication request signal, the gating cycle determination control means detects a synchronization signal and determines that the carrier wave is gating. Mobile identification device, characterized in that said sequential modulating reflector means to said intermittent cycle means determines that the carrier consecutively does not throw the communication request signal when. 2. A method according to claim 1, wherein the stop of the carrier for a predetermined time is used as a synchronization signal.
The information storage means of the transponder has nonvolatile storage means capable of changing the storage content when the power is turned on when the power is on and holding the storage content when the power is turned off. Carrier rectification means for rectifying the radio wave, and powering the information storage means, the sequential modulation reflection means, and the intermittent period determination control means. When the transmission is started and immediately before the transmission of the carrier wave from the interrogator is stopped, the information storage means holds the address of the transmitted communication data in the memory in the nonvolatile storage means and the carrier wave is transmitted again. mobile identification apparatus according to claim 1, wherein the resume transmission of communication data not sent to. 3. An interrogator, comprising: a right / wrong determining unit for determining whether the output of the receiving / demodulating unit is right or wrong; The memory means has second periodic intermittent means for transmitting a carrier wave continuous with the synchronization signal in a cycle shorter than a cycle for updating the address of the communication data in the memory, and the non-volatile information means of the transponder has 3. The communication device according to claim 1, wherein the sequential modulation and reflection means retransmits the communication data when the address of the data in the memory is not updated.
Placing the mobile identification device.