JPS62294346A - Mictowave data transmission equipment - Google Patents

Abstract

PURPOSE:To eliminate the need for special consideration such as linearly polarized wave processing at an antenna installing position for a questionnaire device and a reply device by using a circularly polarized wave so as to communicate information. CONSTITUTION:A microwave carrier in first frequency f1 from the questionnaire 101 is sent as a radio wave w4 of a left rotatory circularly polarized wave (carrier of non-modulation) via a transmission/reception antenna 13. The radio wave w4 is caught by a left/right rotatory circularly polarized wave antenna 24 in common use for transmission/reception of the reply equipment 201, demultiplexed by a circularly polarized wave antenna feeding circuit 25 and sent to a modulator 28. In such case, a CPU in a signal processing unit 27 sends the data information stored in a RAN to the modulator 28 by the recognition of the reception of the radio wave w4 of the left rotatory circularly polarized wave first frequency f1 from the questionnaire device 101 in a signal processing unit 27. The modulator 28 used data information so as to modulate the non-modulation received carrier.

Description

Detailed Description of the Invention 3. Technical Field of the Invention The present invention relates to a microwave data transmission device that transmits and receives information using microwaves.

<Prior Art> Conventionally, there has been a microwave data transmission device having a structure shown in FIG. 2 for transmitting and receiving information using microwaves.

In Fig. 2, 1 is an interrogator and 2 is a transponder, and when the interrogator 1 interrogates the transponder 2 using a microwave signal,
The transponder 2 transmits fixed information stored therein to the interrogator 1 using a microwave signal. The above-mentioned interrogator 1 receives a signal from the J microphone (a signal generator that generates a 1-wave signal, and a signal generator that generates a 1-wave signal, and transmits it into the air as a radio wave, and a radio wave sent from the transponder 2. A transmitting/receiving dual-purpose vertical/horizontal linearly polarized antenna 3 is provided, and a demodulator is provided for demodulating the microwaves from the transmitting/receiving vertical/horizontal linearly polarized antenna 3. A transmitting/receiving vertical/horizontal/horizontal linearly polarized antenna 4 that catches the radio waves sent from the antenna 1 or transmits the modulated microwaves; a demodulator 6 that demodulates the signal, a signal processor 7 that includes a power supply circuit, a CPU, ROM, RAM, etc. and performs various signal processing; A modulator 8 that performs modulation is provided.

In the conventional microwave data transmission device having the above configuration, the signal sent from the signal generator of the interrogator 1 is
The signal is transmitted from the transmitting/receiving vertically horizontal linearly polarized antenna 3 toward the transponder 2 as a vertically linearly polarized radio wave w1. This transmission signal is an unmodulated carrier wave with a frequency fl, which is received by the transceiver/vertical/horizontal linearly polarized antenna 4 of the transponder 2, and transmitted to the modulator 8j via the feeder circuit 5 equipped with a polarization separation function. It will be done. On the other hand, the signal processor 7
The code information signal stored therein is sent to the modulator 8.
The carrier wave is modulated by this signal. After undergoing this modulation, the modulated signal is sent out into the air toward the interrogator 1 by the transmitting/receiving vertical/horizontal linearly polarized antenna 4 of the transponder 2 as a vertically linearly polarized radio wave w2.

In the interrogator 1, the radio wave w2 from the transponder 2 is received by the transmitting/receiving vertical/horizontal linearly polarized antenna 3, and is demodulated by the demodulator to read the fixed information stored in the transponder 2 in advance.

On the other hand, when the interrogator l rewrites the information held inside the signal processor 7 of the transponder 2, the vertically polarized radio wave wl used to read the above information is used, and a carrier wave of a frequency f2 different from w2 is used. This modulated signal is transmitted from the antenna 3 as a horizontally polarized radio wave w3. This transmitted radio wave w3 is received by the antenna 4 of the transponder 2, which is installed so that the antenna 3 of the interrogator 1 and the sensing polarization direction thereof match, and is guided to the demodulator 6 through the feeding circuit 5. The signal demodulated by the demodulator 6 is input to the signal processor 7, and the information held within the signal processor 7 is rewritten by the demodulated signal. In this conventional method, as mentioned above, the frequency of the transmitting/receiving signal for reading and the transmitting signal for rewriting are adjusted to prevent interference between them and the data being read or rewritten by mistake. They also used orthogonal linear polarization. However, in the above microwave data transmission device, since two orthogonal linearly polarized waves are used, the antenna 4 of the transponder 2 and the antenna 3 of the interrogator 1 are adjusted so that the sensing polarization directions match each other. Therefore, there were restrictions in the installation of transponders, which were supposed to be attached to moving objects.

<Purpose> The present invention was made to solve the various problems mentioned above, and it is possible to identify signals by using circularly polarized waves of different frequencies and different directions of rotation in the two systems of reading and writing. It is an object of the present invention to provide a microwave data transmission device in which a transponder can be freely installed without reducing the efficiency.

<Structure of the Invention> In order to achieve the above object, the present invention provides a microwave data transmission device with mutually different first and second polarization directions (
an interrogator comprising: transmitting means for transmitting microwave signals of two types of circularly polarized waves (right-handed or left-handed); and receiving means for receiving microwave signals in a first polarization direction; detects the microwave signal in the first polarization direction transmitted from the carrier, modulates the carrier wave based on the data in the storage unit, and converts the modulated microwave signal in the first polarization direction to the carrier wave. A response comprising a transmitting means for transmitting to an interrogator, and a rewriting means for detecting a microwave signal in a second polarization direction sent from the interrogator and rewriting data in a storage unit based on the signal. It is equipped with a container.

<Embodiment> Hereinafter, an embodiment of the microwave data transmission device according to the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a block diagram of an embodiment of a microwave data transmission device according to the present invention.

In the same figure, 101 is an interrogator, and the interrogator 101 includes a transmitting circuit that transmits microwave signals of different first and second frequencies fl and f2, and receives a microwave signal of a first frequency f1. A transmitter/receiver having a receiving circuit, and a polarization separation/combiner for transmitting in mutually different polarization directions (right-handed or left-handed, and at different frequencies) are provided. Furthermore, there is a dual-polarized antenna I for transmitting and receiving, which transmits and receives microwave radio waves to (or from) the air.
3 is connected.

Further, 201 is a transponder, and the transponder 201 includes a circularly polarized antenna feeding circuit 25 that separates the microwave signal emitted from the interrogator 101, a demodulator 26 that demodulates the microwave signal, and a modulator that modulates the microwave signal. 28, and C- which performs various signal processing.
Power supply circuit and CPU consisting of low power consumption circuits such as MOSIC.

A signal processor 27 containing ROM, RAM, etc. is provided. Furthermore, there is a left and right polarized antenna 24 for transmitting and receiving microwave radio waves from (or to) the air.
is connected.

Next, the operation of the microwave data transmission apparatus will be explained in detail below.

First, reading out data information held in the transponder 201 will be explained.

A microwave carrier wave with a first frequency f1 is transmitted from the interrogator 101 via the transmitting/receiving antenna 13 as a left-handed circularly polarized radio wave w4-.
(This is an unmodulated carrier wave). Left-handed circularly polarized radio waves transmitted by the above transmitting/receiving antenna I3
4 is gated by the left and right polarized antenna 24 for both transmission and reception of the transponder 201, and the caught signal is separated by the circularly polarized antenna feeding circuit 25 and sent to the modulator 28. At this time, the signal processor 27 recognizes that it has received the left-handed circularly polarized radio wave w4 of the first frequency r1 from the interrogator 101.
The PU sends data information stored in RAM to modulator 28 . The modulator 28 modulates the unmodulated carrier wave received via the circularly polarized antenna feeding circuit 25 using the data information. This modulated wave is radiated as a left-handed polarized radio wave W5 having the same rotational direction as the radio wave received toward the interrogator 101 from the left and right polarized antenna 24 for both transmitting and receiving purposes, and is received by the transmitting and receiving antenna 13 in the interrogator 101. Then, the received wave is detected by the transceiver of the interrogator 101, and the data information stored inside the signal processor 27 is extracted.

Next, when it is desired to change the data information held in the transponder 201, the interrogator 101 sends a microwave signal of a second frequency f2 modulated by the write data signal to a right-handed circularly polarized wave via the transmitting/receiving antenna I3. Transmit as radio wave W6. The above writing data signal is sent to the transmitting/receiving antenna 13.
When the radio wave W6 is transmitted from the transponder 201, the left and right polarized antenna 24 for both transmission and reception receives the radio wave W6, separates the received signal via the circularly polarized antenna feeding circuit 25, and demodulates it. The signal processor 26 demodulates the signal and guides the demodulated signal to the signal processor 27. The signal processor 27 rewrites the contents of the stored data held in the internal RAM according to the demodulated signal.

Due to the orientation of the circularly polarized waves, there is no interference between the signals. In other words, in the radio waves flying in the air, the signals that are modulated and superimposed on the carrier wave are the left-handed polarized wave W5 and the right-handed circularly polarized wave W6, and these are polarized waves that are different from each other in the direction of polarization (with respect to the direction of travel). Since the clockwise and counterclockwise directions are different, it is possible to prevent interference on the receiving side.Furthermore, the left-handed circularly polarized wave w5 and the right-handed circularly polarized wave w6 have different frequencies, which further prevents interference. It can be prevented.

The microwave data transmission device having the above configuration can be applied to production control in a factory, warehouse management, parking lot management, or room entry/exit control by having a person carry a transponder. For example, when using it for production control in a factory, a transponder is attached to each part, with individual data such as the part code number, processing procedure, transport route, etc. of the parts on the production line input into memory in advance. Interrogators should be installed at major points on the production line. The interrogator transmits microwaves to transponders installed in each component flowing on the production line, reads the internal data as described above, and outputs a control signal to control the flow of the line. Since microwaves pass through plastic decks, wood, etc., there is no need to install a transponder on the surface of each part.

<Effects of the Invention> According to the present invention, since information is communicated using circularly polarized waves in a microwave data transmission system, linearly polarized waves are not transmitted at the installation positions of the interrogator and transponder antennas. There is no need to take such special considerations. In particular, since there is no need to take special consideration regarding the direction of the antenna of a transponder generally installed on a moving object, the degree of freedom in installing the transponder is dramatically increased and handling becomes easier.

Therefore, it is possible to obtain a microwave data transmission system that can be applied to a wide range of fields of use.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of a microwave data transmission device according to the present invention, and FIG. 2 is a block diagram of a conventional microwave data transmission device. 13 in the figure, transmitting and receiving antenna 24. Transmitting/receiving antenna 25: Circularly polarized antenna feeding circuit 26; Demodulator 27: Signal processor 28: Modulator 101 Interrogator 201: Responder

Claims (1)

[Claims] 1. Transmitting means for transmitting two types of circularly polarized microwave signals having first and second polarization directions (right-handed or left-handed) different from each other; and a first polarization direction. an interrogator comprising a receiving means for receiving a microwave signal, and a microwave signal in a first polarization direction transmitted from the interrogator is detected, and a carrier wave is detected based on data in a storage unit. transmitting means for applying modulation and transmitting the modulated microwave signal in the first polarization direction to the interrogator; and detecting the microwave signal in the second polarization direction sent from the interrogator. and a transponder equipped with rewriting means for rewriting data in a storage unit based on the signal.