JP2862100B2 - Mobile communication system and mobile communication device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a mobile communication system, and more particularly to a communication system capable of performing high-speed communication and reducing power consumption of a mobile communication device.

BACKGROUND ART A mobile communication system that performs communication between a communication device (interrogator) provided on a fixed side and a simple communication device (responder) provided on a mobile body side called a tag has attracted attention. In this case, an inquiry signal is issued to a transponder carried by an object or person who has reached the communication area, and the object or person is recognized in a non-contact manner by an identification signal returned from the transponder. in use.

In such a mobile communication system, the power supply of the transponder often uses a battery because of its simplicity and light weight, and one problem is to reduce power consumption and extend the battery life.

As a method for solving this, as shown in FIG. 8, power is always supplied only to the circuit 64 necessary for receiving the interrogation signal,
At the time of receiving the interrogation signal, the power consumption is reduced by activating the switch circuit 600 and supplying power to the remaining signal processing means 65 (for example, Japanese Patent Application Laid-Open No. 61-201177; The former is called).

On the other hand, as shown in FIG. 9, the unmodulated wave from the interrogator 75 is received by the transponder 70, the identification information is added to the response wave, and the response wave is returned to the interrogator 75. There is a transponder 70 for identifying information (Japanese Unexamined Patent Publication No. 57-79).
No. 476, hereinafter referred to as the latter). However, the latter communication system shown in FIG. 9 has the above configuration, and therefore can only read preset identification information. Moreover, in order to make the transponder 70 small and simple in circuit configuration, the configuration of the code generation means 74 and the low-frequency generation means 73 for providing information is also simple, so that the identification information is at most several hundred bits (numbers). 1
(0 bytes) is the limit, and storage management of a large amount of information such as several thousand bytes is extremely difficult. Then, all the processing information based on the read identification information needs to be stored and managed in the interrogator 75 side, and the number of transponders 70 is increased. There are problems to be solved practically, such as enlarging and complicating the system. By the way, the former communication system is intended only for data reading from now on, mainly for the identification of the transponder. However, in recent years, for the application to a wider field, it is necessary to provide the transponder with the transponder. It is necessary to issue various command signals from the interrogator for instructing transmission of various data, or to write various data signals from the interrogator to the storage unit of the transponder.

In this case, it is necessary to increase the data transmission speed in order for the transponder to communicate necessary commands or data signals in a short time while passing through the communication area with the interrogator. It is necessary to set the frequency band high enough to cover the data transmission speed, which inevitably raises the problem of increasing the power consumption of the receiving unit to which the power is always supplied.

More specifically, in the former, the power must always be supplied to the start circuit 64 (generally including the amplifier circuit) in order to receive the start signal, but the power is always supplied to the signal processing means 65 including the frequency conversion circuit and the code conversion circuit. Although the idea is that power consumption is smaller than supplying power, in this case, in consideration of writing a data signal to the transponder, the data signal is received after receiving the activation signal.
Therefore, when trying to transmit a high-speed data signal, the starting circuit
The 64 requires a high frequency band corresponding to the data transmission rate so that the waveform of the high-speed data signal is not distorted and a predetermined gain is sufficiently obtained.

Generally, the current consumption of such a circuit (a signal amplification circuit included in the start-up circuit) increases in proportion to the height of the frequency band. Therefore, in the former method, the standby state of the start-up circuit 64 which also receives a high-speed data signal is required. The current consumption at the time is greatly increased.
In addition, when the data transmission time is shortened by increasing the transmission speed, the ratio of the power constantly consumed by the starting circuit 64 to the power consumption of the entire transponder increases. Therefore, there has been a problem that the former transponder cannot perform high-speed transmission.

On the other hand, attempts have been made to use the latter mobile communication system for production instructions and distribution management on production lines in factories, and in such applications, the transmission data is relatively large, with tens or thousands of characters. Therefore, it is desired that data can be transmitted reliably and at high speed within a limited communication time under a noise environment.

Then, the present inventors not only read out the identification signal,
Various kinds of large amounts of information can be written or read to the mobile communication device (responder) at high speed and with high quality. In addition, the transponder has devised a mobile communication system and a mobile communication device that can manage and store such information and consume less power and have a longer life despite high-speed transmission.

DISCLOSURE OF THE INVENTION The present invention solves such a problem, and provides a mobile communication system capable of high-speed data transmission to a mobile communication device and capable of extremely reducing power consumption of the communication device. The purpose is to do.

Another object of the present invention has been made under the above-mentioned demands, and has as its object to provide a mobile communication system which realizes reliable and high-speed data transmission.

As means for solving such a problem, a mobile communication system of the present invention has the following configuration.

That is, the present system includes a communication device provided on the fixed side and a communication device provided on the mobile side, and transmits a data signal to the fixed side communication device at a high speed following a low-speed start signal. Starting means for receiving the start signal and operating the switch means, the start signal receiving means comprising an amplifier having a low frequency band which is always supplied with power and operating the switch means. A data signal receiving means comprising a high frequency band amplifier which is supplied with power and starts receiving the data signal, a signal processing means for outputting data to be transmitted based on the data signal from the data signal receiving means, and A mobile communication system comprising transmission means for transmitting transmission data.

In the communication system having the above configuration, the activation signal transmitted at a low speed from the transmission means of the fixed communication device is received by the activation signal receiving device of the mobile communication device which is constantly supplied with power. Upon receiving the start signal, the start signal receiving means activates the switch means to supply power to the data signal receiving means, the signal processing means, and the transmitting means. The mobile communication device that has been activated by being supplied with power supplies the fixed communication device with a predetermined response signal to notify that the fixed communication device has been activated. The fixed-side communication device that has received the response signal starts transmitting the data signal at a high speed following the activation signal from the transmitting unit. The high-speed data signal is received by the data signal receiving means on the side of the moving body which has been supplied with power and started operating, and after signal processing by the signal processing means, sends a response or data based on the processed result to the fixed side by the transmitting means. Send to communication device.

Since the start signal is transmitted at a low speed irrespective of the transmission speed of the high-speed data, the frequency band of the start signal receiving means for receiving the start signal may be low in accordance with the transmission speed of the start signal. It can be kept very small.

When data communication is required, power is supplied to a data signal receiving means having a high frequency band, thereby enabling high-speed data transmission. The current consumption of the data signal receiving means is increased by the higher frequency band, but the time required for data communication is sufficiently shorter than the time during which the power of the start signal receiving means, which is always supplied with power, is supplied. At the same time, the transmission time is shortened in inverse proportion to the transmission speed, so that the power consumption per unit data hardly changes.

Accordingly, a communication system that satisfies conflicting demands of high-speed transmission and low power consumption has been realized.

Next, another configuration of the present invention will be described. The communication device provided on the fixed side sends inquiry data, and the communication device provided on the moving body (not shown) returns response data or the fixed side communication. In a mobile communication system for transmitting data from a device and storing the data in a mobile communication device, an entry detecting means for detecting that the communication device provided on the mobile device has entered the good communication range of the fixed communication device. The fixed-side communication device is started by the entry detection means, and the fixed-side communication device has an oscillation means for generating a carrier wave in the microwave band, Data generating means for generating the interrogation data with no data frame length, transmitting means for transmitting the unmodulated carrier, and modulation for modulating the carrier at high speed with the interrogation data. Means and transmitting means for transmitting the modulated carrier wave, and a demodulating means for demodulating the signal after the detection and the detection of the modulated carrier wave to obtain the response data, the mobile communication device, Modulated carrier wave receiving means and received signal detecting means, starting signal receiving means for receiving the starting signal and activating the switching means, further demodulating means for demodulating the signal after detection and obtaining the interrogation data, Data generating means for generating the response data with a data frame length not exceeding a fixed byte range,
Modulation means for high-speed modulation of the received unmodulated carrier wave with the response data and transmission means for returning the modulated carrier wave are provided. Here, the data frame length that does not exceed a certain byte range means that when the data amount to be transmitted is less than a certain byte range, the data amount to be transmitted is the data frame length, and the data amount to be transmitted is If the length is longer than a certain byte range, the amount of data to be transmitted is divided by the data frame length of the certain byte range, and the amount of data transmitted at a time is divided into data frame lengths that make the certain byte range the maximum length. Say that.
In addition, the existence region of the radio wave radiated from the transmitting means of the fixed communication device generally has a sufficiently strong electric field strength, a region I in which reliable communication can be performed, a region III outside in which communication is impossible, and an intermediate region therebetween. It consists of the area II where the electric field strength fluctuates and transmission errors easily occur. Here, the good communication area is referred to as area I. By starting communication by the entry detecting means when the mobile communication device enters the area I, reliable communication with extremely few transmission errors can be performed. If the data frame length is less than a certain byte range,
That is, preferably in the 64-64 byte range, 64
If it is less than bytes, for example, when transmitting a few hundred characters to several thousand characters with a commonly used 16-byte data frame length, it must be sent in tens to hundreds of data frames, which means that It takes a time to check whether the data is correct for each frame, and as a result, the transmission efficiency is reduced and the speed cannot be increased. If it exceeds 512 bytes, even if advanced error detection (such as CRC) described later is used, the oversight rate for reading a large number of characters will increase, and the error detection efficiency will decrease. If so, a large number of characters must be transmitted again, resulting in a practical problem that transmission efficiency is deteriorated. Therefore, in the present invention, the data frame length is within the range of 64 to 512 bytes, more preferably the range of 128 to 256 bytes, which satisfies both the practical improvement of the error detection rate and the high speed (see FIG. 5).

In the mobile communication system having the above-described configuration, communication between the communication devices is performed in the microwave band after the entry detection unit detects that the communication device provided in the mobile unit has entered the good communication range (the above-described area I). Since the communication is started with a direct wave by a carrier wave, reliable communication is performed under a sufficient radio wave intensity.

Further, since the microwave carrier is modulated and transmitted / received at high speed with question data and response data having a long data frame length in the range of 64 to 512 bytes, a large amount of data is communicated at high speed within a short time.

As described above, according to the mobile communication system of the present invention,
Communication between the fixed communication device and the mobile communication device can be performed at high speed and reliably.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing the overall configuration when the mobile communication system of the present invention is applied to tag communication, and FIG. 2 shows an example of a specific configuration of a start signal receiving means and a data signal receiving means. FIG. 3 is a diagram showing a frequency band and a gain relationship relating to the amplifying means, FIG. 4 is a signal time chart, FIG. 5 is a diagram explaining transmission characteristics, and FIG. 6 is another diagram of the present invention. FIG. 7 is a schematic perspective view of a mobile communication system including a transponder detector, and FIGS. 8 and 9 are block diagrams showing a conventional apparatus.

BEST MODE FOR CARRYING OUT THE INVENTION A mobile communication system according to the best mode of the present invention includes a communication device provided on a fixed side and a communication device provided on a mobile side, and is activated from the fixed side communication device. The mobile communication device that has been supplied with power to all circuits and has started operation modulates the radio wave radiated from the fixed communication device with a predetermined code and returns a response to continue communication of commands and data. A communication system, wherein the fixed-side communication device transmits a high-speed data signal following a low-speed start signal for transmission to a mobile-side communication device, and provides a transmission clock to the transmission unit. A modulating means comprising a clock generating means, a carrier oscillating means and a modulator for modulating a high frequency oscillated by the transmitting signal, and emitting the high frequency modulated by the transmitting signal as radio waves Antenna means for emitting light.

The mobile communication device further includes: a detection unit that detects a start signal or a data signal from a received radio wave; a start signal reception unit that amplifies and processes a low-speed start signal among the detected reception signals; Data signal receiving means for amplifying and processing a high-speed data signal among signals, a switch means for turning on a switch at the output of the start signal receiving means and supplying power to the data signal receiving means and other signal processing means and transmitting means. In addition to the above, the activation signal receiving means has a low frequency band corresponding to a low-speed activation signal, and is in an operation state in which power is constantly supplied and waits for an activation signal from the fixed-side communication device. Further, the data signal receiving means has a high frequency band sufficiently covering a high-speed data signal, and is supplied with power only by a start signal and operates.

Here, the configurations of the activation signal receiving means and the data signal receiving means will be described in detail with reference to FIG.

The start signal receiving circuit 21 includes an amplifier circuit A1 for the low-speed start signal detected by the detection circuit 25 and a comparator C1 for signal conversion to a logic level connected to the subsequent stage. Input to the control terminal. Here, a configuration may be employed in which the output of the amplifier circuit A1 is directly input to the control terminal of the switch circuit 23 and the signal conversion comparator C1 is not provided. The data signal receiving circuit 22 comprises an amplifying circuit A2 for the high-speed data signal detected by the detecting circuit 25 and a comparator C2 for signal conversion to a logic level connected to the subsequent stage. The signal is input to the signal processing circuit 26 as shown.

The relationship between the frequency of the input signal to each of the amplifier circuits A1 and A2 and the frequency band and gain of the amplifier circuits A1 and A2 is the third.
As shown in the figure, the amplification circuit A1 included in the activation signal receiving circuit 21 can obtain a predetermined gain only in a low frequency band enough to cover the frequency of the low-speed activation signal, but is included in the data signal receiving circuit 22. The amplifier circuit A2 has a predetermined gain up to a high frequency band covering the high-speed data frequency.

Here, "low speed" refers to a case where the activation signal is slower than the transmission speed of the data signal, and "high speed" refers to a case where the transmission speed of the data signal is faster than the transmission speed of the activation signal. (For example, when the transmission speed of the activation signal is several Kbps or less and the transmission speed of the data signal is several Kbps or more, the activation signal is called low-speed and the data signal is called high-speed, respectively.) Refers to a frequency band in which the low-speed start signal can be transmitted and received without distortion (for example, several tens KHz or less). A high frequency band means that a high-speed data signal can be transmitted and received without distortion (for example, several tens KHz). (KHz or higher).

First Embodiment FIG. 1 shows an example in which the present invention is applied to a so-called tag communication system. In the figure, the fixed-side communication device is an interrogator 1, which is fixedly provided at a desired place. The interrogator 1 includes a transmission circuit 11 for transmitting a start signal or a data signal including an instruction, which will be described in detail later, a clock generation circuit 12 for supplying a predetermined clock to the transmission circuit 11 to change a signal transmission speed, Modulation circuit that modulates the carrier of frequency f1 oscillated by oscillator F1 with the signal sent from 11
13, a transmitting antenna 14 for transmitting a modulated wave as a radio wave, a transmitting / receiving circuit 15 for generating a high-frequency carrier wave of an unmodulated frequency f2 from the oscillator F2 and extracting a data signal from the returning carrier wave modulated by the transponder 2, It comprises a connected transmitting / receiving antenna 16 and a signal processing circuit 17 including a microcomputer.

The mobile communication device 2 is a transponder (tag), and is attached to a mobile such as an assembly moving on a production line or a running automobile. The transponder 2 includes a start signal receiving circuit 21 for receiving the start signal, a data signal receiving circuit 22 for receiving the data signal, a switch circuit 23 operated by the start signal receiving circuit 21, and the transmitting antenna 14.
A receiving antenna 24 for receiving a radio wave transmitted from the receiving antenna 24, a detecting circuit 25 connected to the receiving antenna 24 for detecting a modulated wave and obtaining the starting signal or the data signal, a signal processing circuit 26 including a microcomputer, and storing data. Memory circuit 2
7, a transmission circuit 28 for transmitting a data signal including an identification signal,
It comprises a transmitting / receiving antenna 29 for receiving the unmodulated carrier at the frequency f2, modulating it with a data signal, and returning it, and a power supply 30 such as a battery.

Then, the power supply 30 includes the activation signal receiving circuit 21,
The switch circuit 23 and the detection circuit 25 are directly connected, and the data signal reception circuit 22, the signal processing circuit 26, the storage circuit
27 and the transmission circuit 28 are connected to the power supply 30 via the switch circuit 23.

In the communication system having the above configuration, the signal processing circuit 17 of the interrogator 1 sets the output clock of the clock generation circuit 12 to a predetermined low frequency by the control signal 17a, and sends out a start signal to the transmission circuit 11. The start signal is input to the modulation circuit 13 as a pulse start signal (FIG. 4 (1)) synchronized with the output clock, and the frequency oscillated by the oscillator F1
The transmission wave is transmitted from the transmission antenna 14 as a radio wave obtained by modulating the carrier of f1 with the activation signal. At the same time, the signal processing circuit 17 activates the transmission / reception circuit 15 by the control signal 17b, and the oscillator F2
The transmission / reception antenna 16 transmits the unmodulated wave of the frequency f2 oscillated in the above. In the present embodiment, separate oscillators of frequencies f1 and f2 are used and two oscillators F1 and F2 are used, but the same frequency may be used. In this case, one of the oscillators is used. May be.

When the transponder 2 attached to the mobile body enters the communication area of the interrogator 1, the radio wave of the frequency f1 modulated by the activation signal by the receiving antenna 24 is received and detected, and the activation signal having a low frequency band is detected. Input to the receiving circuit 21. The receiving circuit 21 which has received the start signal issues a switch operation signal to activate the switch circuit 23, thereby
Power supply to 22, 26, 27, and 28 is started.

The signal processing circuit 26 starts operating and transmits an identification signal to the transmission circuit.
Send to 28. The transmission circuit 28 modulates the unmodulated wave reaching the transmission / reception antenna 29 with the identification signal and returns it to the interrogator 1. The interrogator 1 receives the modulated radio wave by the transmission / reception antenna 16 and takes in the identification signal into the signal processing circuit 17 via the transmission / reception circuit 15.

When confirming the identification signal, the signal processing circuit 17 again issues a control signal 17a to the clock generation circuit 12, sets the output clock to a predetermined high frequency, and outputs a data signal to the transmission circuit 11. The data signal is input to the modulation circuit 13 as a pulsed data signal (FIG. 4 (2)) synchronized with the high frequency clock output, and transmitted from the transmission antenna 14 as a radio wave obtained by modulating a carrier of frequency f1 with the data signal. You.

The radio waves are received by the receiving antenna 24 of the transponder 2, detected, input to the data signal receiving circuit 22 having a high frequency band, and reach the signal processing circuit 26 via the signal. Signal processing circuit 26
If the data signal is pure data, the data signal is stored in the storage circuit 27, and if the data signal is a read command, a necessary data signal is read from a predetermined address of the storage circuit 27, and this is transmitted to the transmission circuit 28. And modulates the unmodulated wave of frequency f2 with the data signal and sends it to the interrogator 1 via the transmitting / receiving antenna 29.

At the end of the communication, for example, a stop signal is transmitted from the signal processing circuit 17 of the interrogator 1. This is input to the data signal receiving circuit 22 of the transponder 2 via the antennas 14 and 24,
The operation of the switch circuit 23 is stopped by the output of 26,
The power supply to the circuit 26 and the other circuits 22, 27, 28 is completed. In our experiments, high-speed transmission (for example, 32 Kbps)
The current consumption during standby is about 10
Although the current was 0 μA, it was reduced to about 1/20 to about 1/20 in this method.

In the above embodiment, all or a part of the functions of the transmission circuit 11 and the clock generation circuit 12 of the interrogator 1 may be processed by software of the signal processing circuit 17, and the storage circuit 27 of the transponder 2 may be processed. When a random access memory (RAM) is used, power is always supplied to it.

Second Embodiment In FIG. 7, a transponder (tag) 102, which is a mobile communication device, whose structure is described in detail, is provided on a mobile M (not shown) that moves in the direction of the arrow. Above the moving passage 105, a pair of antennas 114 and 118 are provided.
Reference numerals 4 and 118 denote an interrogator as a fixed-side communicator having a communication range in an I region having a shape close to a circle including a part of the moving passage 105.
101 have been followed.

In the region I, the receiving-side phototubes 231 and 141 and the light-emitting side phototubes 232 and 142 are respectively installed on the entrance side and the exit side of the moving passage 105 so as to face each other. Connected to the vessel 101. When the transponder (tag) 102 that has reached the moving path 105 enters a region where the radio field intensity in the region I is sufficiently large (the above-mentioned good communication range I) and crosses the opposing photoelectric tube, the light is blocked. Above light receiving side photoelectric tube
An entry detection signal is issued from 231. When the transponder 102 exits from the region I, the light from the light receiving side photoelectric tube 141 is blocked and a leaving detection signal is issued. This photoelectric tube 231, 2
Although 32, 141, and 142 are shown as transmission types in the embodiments, they may be reflection types, or an object detection device such as a limit switch other than the photoelectric tube may be used.

FIG. 6 shows an interrogator including the pair of antennas 114 and 118.
2 shows a circuit configuration of 101 and a transponder 102.

The interrogator 101 has a query data generating means and a signal processing circuit 113 as means for confirming the demodulated response data. The circuit 113 is provided with a microprocessor 131, and a circuit 132 for detecting an error in the response data (such as cyclic redundancy check = CRC) is built in the processor 131 in hardware. The entry detection signal and the exit detection signal of the photoelectric tubes 231 and 141 are input to the signal processing circuit 113.

An oscillation circuit 111 generates a carrier wave in the microwave (2.45 GHz) band. The carrier wave is output from the signal processing circuit 113 to the modulation circuit 115 by query data having a data frame length of preferably 128 bytes or more, for example, 32 Kbps. At high speed and transmitted from the antenna 118. 112
Is an oscillation circuit similar to the oscillation circuit 111, and the antenna 1
14 outputs an unmodulated carrier and a detection circuit 117
Is supplied with a local oscillation signal for homodyne detection.

The detection circuit 117 is connected to the antenna 114 from the transponder 102.
The modulated carrier wave returned to the above is subjected to homodyne detection, and this detected signal is demodulated by a demodulation circuit 116 at the subsequent stage and input to the signal processing circuit 113 as response data.

The transponder 102 has a signal processing circuit 122 as a response data generating means.
As in 1, a microprocessor 221 having an error detection (CRC or the like) circuit 222 built in hardware is provided. The signal for activating the transponder transmitted from the antenna 118 of the interrogator 101 is received by the antenna 124 as an amplitude-modulated carrier, and is transmitted through the detection circuit 125 and the activation signal receiving circuit 130 to the switching means 12.
9 is operated to supply power to the signal processing circuit 122, the storage circuit 127, the demodulation circuit 121, the modulation circuit 123, and the like. Thereafter, the interrogation data from the interrogator 101 to the transponder 102 is received by the antenna 124 at the amplitude-modulated carrier wave emitted from the antenna 118, reproduced into interrogation data via the detection circuit 125 and the demodulation circuit 121, and input to the signal processing circuit 122. I do.

The response data output from the signal processing circuit 122 is input to the modulation circuit 123, and the modulation circuit 123 modulates the non-modulated carrier reaching the antenna 126 at high speed in accordance with the response data and returns the modulated signal to the interrogator 101.

In the mobile communication system having the above configuration, the moving path 10
5 The transponder 102 attached to the mobile unit on the
When entering the good communication range with 18, and crossing the photoelectric tube 231,
Entry detection signal is emitted from the photoelectric tube 231, the start signal responsive 102 from the signal processing circuit 113 having received the is output as an interrogation signal, carrier f ₁ in accordance with this is output from the modulated antenna 118. The modulated carrier is received by the antenna 124, detected and demodulated into identification confirmation data, and processed by a signal processing circuit.
Enter 122. The signal processing circuit 122 outputs a predetermined response signal as a response signal of the completion of activation, and the modulation circuit 123 modulates the unmodulated carrier wave from the antenna 114 in response thereto.
The modulated carrier is received again by the antenna 114, and after detection and demodulation, is input to the signal processing circuit 113 as a response signal.

Thereafter, if necessary, write command data is issued as an interrogation signal, and the interrogator 101 sends write data to the responder 102, or issues read command data, and obtains read data from the responder 102. The signal processing circuit 122 of the transponder 102 stores the data portion in the storage circuit 127 if the data signal is the write command data, and stores the data portion in the storage circuit 127 if the command data signal is the read command.
The necessary data signal is read out from the predetermined address of
3 and send it to the interrogator as data. In transmission and reception of such data, transmission and reception are performed as data having a sufficiently long data frame length of, for example, 128 bytes.
An error is detected by the error detection circuits 132 and 222 for each data frame constituting the data, and when a transmission error occurs, a retransmission command is immediately issued from the interrogator 101 or the transponder 102 in the receiving state.

When the transponder 102 leaves the good communication range across the phototube 141, a exit detection signal is issued from the phototube 141, and a communication end command is issued from the signal processing circuit 113 of the interrogator 101, and the communication state is canceled.

In the above system operation, the communication between the interrogator and the transponder is regarded as a region having a sufficiently high radio wave intensity and a direct wave, so that reliable and reliable communication is possible. In particular, in the present embodiment, transmission error detection is performed for each data frame by hardware using an advanced error detection method, CRC, so that more reliable and prompt communication can be performed as compared to error detection using generally used software. It is possible.

In addition, since communication is performed by direct waves of carrier microwaves,
Low error rate, preferably in the range of 64-512 bytes,
More preferably, efficient communication is possible by high-speed modulation of data having a sufficiently long data frame length in the range of 128 to 256 bytes.

INDUSTRIAL APPLICABILITY In the present invention, a large amount of data communication can be performed in a limited time, and it is easy to collect production instruction information and inspection information in a factory production line. In addition, when data transmission is performed between a transponder mounted on an automobile and a fixed-side communication device (interrogator) on the ground by taking advantage of high-speed transmission, reliable data transmission is ensured even when the automobile runs at high speed. It becomes possible. Since the high-speed communication is possible, a time margin for the double or triple transmission is generated, and the communication can be performed only in a particularly strong range (good communication range) of the electric field strength in the communication area of the interrogator. Thus, the reliability of communication is greatly improved.

────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Yoshihisa Harada 1-13-13 Takami, Chikusa-ku, Nagoya-shi, Aichi Prefecture 5 (72) Inventor Souichi Ishikawa 1-211 Fujimori, Meito-ku, Nagoya-shi, Aichi Prefecture 2-1-2 ( 72) Inventor Takehiko Okuda 2-904 Hirabari, Tenpaku-ku, Nagoya-shi, Aichi Examiner Naohiro Shigeta (58) Fields investigated (Int.Cl. ⁶ , DB name) H04B 1/59 H04B 7/26 G06F 11/00 G06K 19 / 00 G01S 13/78

Claims (7)

(57) [Claims] 1. A transmission device comprising a communication device provided on a fixed side and a communication device provided on a mobile body side, wherein the fixed-side communication device transmits a data signal at a high speed following a low-speed start signal. Starting means receiving means comprising a low-frequency-band amplifier which is always supplied with power, receives the starting signal and activates the switch means, and an operation of the switch means. A data signal receiving means comprising a high frequency band amplifier which is supplied with power and starts receiving the data signal,
A mobile communication system comprising: signal processing means for outputting data to be transmitted based on a data signal from the data signal receiving means; and transmission means for transmitting transmission data. 2. A receiving means provided in a moving body for receiving a high-speed data signal following a low-speed start signal, and an operation signal which is always supplied with power and amplifies a low-speed start signal preceding the high-speed data signal. Starting means comprising an amplifier having a low frequency band for outputting a signal, a switch means for supplying power based on an operation signal output from the starting means, and when power is supplied from the switching means, the receiving means receives a start signal from the receiving means. Signal receiving means comprising an amplifier having a high frequency band for amplifying a data signal outputted by the signal processing means, and signal processing means for performing signal processing on the amplified data signal outputted from the data signal receiving means and outputting transmission data. And a transmitting means for transmitting the data signal output from the signal processing means. 3. The fixed-side communication device includes: a transmission unit that transmits a high-speed data signal following a low-speed start signal for transmission to a mobile-side communication device; and a clock that supplies a transmission clock to the transmission unit. It is characterized by comprising: a generating means, a oscillating means for a carrier wave, a modulating means comprising a modulator for modulating a high frequency oscillated by the transmitting signal, and an antenna means for radiating the high frequency modulated by the transmitting signal as a radio wave. The mobile communication system according to claim 1. 4. A mobile communication device, comprising: detecting means for detecting a starting signal and a data signal from a received radio wave; starting signal receiving means for amplifying and processing a low-speed starting signal among the detected received signals; Data signal receiving means for amplifying and processing a high-speed data signal among the received signals, and turning on a switch at the output of the activation signal receiving means to supply power to the data signal receiving means and other signal processing means and transmitting means The mobile communication system according to any one of claims 1 to 3, further comprising switch means for performing the switching. 5. A mobile communication system in which question data including write data is sent from a communication device provided on a fixed side, and response data including read data is returned from a communication device provided on a mobile side. Providing means for detecting that the fixed communication device has entered the good communication range, so as to start the operation of the fixed communication device by the entry detection means, and, in the fixed communication device, Oscillating means for generating a carrier wave in the microwave band, data generating means for generating the interrogation data with a data frame length not exceeding a certain byte range, transmitting means for transmitting the unmodulated carrier wave, and A modulating means for performing high-speed modulation with the query data and transmitting the data; and a demodulating means for demodulating the modulated carrier wave to obtain the response data. A demodulation means for demodulating the modulated carrier wave to obtain the interrogation data; a data generation means for generating the response data with a data frame length not exceeding a predetermined byte range; And a transmitting means for modulating the carrier with the response data and returning the modulated carrier. 6. The mobile unit according to claim 5, wherein said data generating means generates question data and response data with a data frame length in a range of 64 to 512 bytes as a maximum frame length. Communications system. 7. The mobile unit according to claim 5, wherein said data generating means generates question data and response data with a data frame length in a range of 128 to 256 bytes as a maximum frame length. Communications system.