JP4719496B2 - Mobile radio communication system - Google Patents

Description

  The present invention relates to a mobile radio communication system that performs radio communication between a master station and a slave station mounted on a mobile body, and in particular, a master station installed in a railway station or the like and a slave station mounted on a train. The present invention relates to a train radio communication system that performs radio communication with the train.

  FIG. 11 shows an example of an Automatic Train Stop (ATS) system used for ensuring the safety of train operation around a railway station. FIG. 12 is a plan view of the periphery of (A) indicated by the broken line in FIG. 11 as viewed from above.

  In this ATS system, a ground unit 16 is installed at a necessary location on the rail 11 and is connected to the information transmission device 14 by a cable 15. The ground unit 16 transmits digital information such as the signal type and distance information of the stop signal device 13 to the vehicle upper unit 17 installed in the train 12, and the vehicle unit 17 receives information received from the ground unit 16 as information. The data is transferred to the cab device 19 via the transmission device 18.

  On the other hand, recently, there is a need for more advanced various controls by adding various data such as train number information and driver identifiers to the contents of data communication between on-board systems and ground systems of passing trains and stopped trains. It is growing.

  As a method for inexpensively transmitting and receiving various data to and from a passing train, it is conceivable to use a wireless transmission / reception device for the ground system and the on-board system. However, in digital mobile communication, the Doppler shift is performed depending on the relative speed between the transmitting station and the receiving station. It is widely known that the occurrence of the error, it becomes difficult to correctly demodulate the received signal, and the bit error rate (BER) deteriorates.

  As a method of correcting the Doppler shift, for example, as described in Patent Document 1 below, the latitude, longitude, and moving speed of a mobile station are measured using a global positioning system (GPS) and measured in advance. There is known a system that calculates a Doppler shift from a relative position with respect to a base station and finely adjusts a local frequency of a transmission apparatus based on the calculation result.

  Further, a method of detecting the speed of a moving body using a speed detector and correcting a Doppler shift as in Patent Document 2 below, or a Doppler in mobile communication using an artificial satellite as in Patent Document 3 below. A method for correcting the shift is also known.

In addition, as a vehicle position detection device, an inexpensive and high-performance frequency-modulated continuous wave (FM-CW) in-vehicle radar using a millimeter wave band has recently been installed in a general passenger car. It is used as a safety technology that measures the relative distance and relative speed with the vehicle ahead and reduces damage when it collides with the vehicle ahead.
JP 2003-309517 A Japanese Patent Laid-Open No. 05-022183 Special table 2001-509324 gazette

However, the above-described conventional train radio communication system has the following problems.
The ATS system is a security system that issues a warning to the crew and automatically stops the train when the train tries to enter the signal position beyond the indicated speed of the stop signal by performing position notification and data communication to the train It is. However, when a new ATS system is introduced to an existing track, as shown in FIGS. 11 and 12, a laying work is required to lay the signal line or power line cable under the rail to install the ground element. As a result, economic problems occur, such as enormous construction costs.

  As a method for solving the problem of the construction cost, a method of constructing an ATS system by providing an inexpensive and high-performance radar device and a wireless transmission / reception device in a ground system and a wireless transmission / reception device in an on-board system can be considered. However, when communication between a train moving at high speed and a ground system using a wireless transmitter / receiver in the microwave band or millimeter wave band, a Doppler shift corresponding to the speed of the train occurs in the received radio wave, and the BER deteriorates. To do.

  In the above Patent Document 1, GPS is used for Doppler shift correction. However, this method is applied to cases where it is difficult to receive radio waves from GPS satellites due to shielding by station structures or weather conditions, or in subways and the like. Can not do it.

  It is an object of the present invention to influence the Doppler shift without increasing the circuit size, size, and cost of a wireless transmission / reception device in wireless communication between a moving body such as a train moving at high speed and a ground system. Is to provide a stable quality wireless line.

  Another problem of the present invention is to construct a train operation management system such as an ATS system at a low cost.

FIG. 1 is a principle diagram of a mobile radio communication system in the first to third aspects of the present invention.
In the first aspect of the present invention, a wireless communication apparatus includes a measurement unit 101, a control unit 102, a variable frequency oscillation unit 103, a modulation unit 104, and a transmission unit 105, and is a mobile wireless communication device installed in a mobile body 111. Data is transmitted to 112.

  The measuring means 101 transmits a radar wave, receives the radar wave reflected by the moving body 111, and measures the Doppler shift frequency. The control means 102 outputs a control signal for correcting the Doppler shift based on the measured frequency, and the frequency variable oscillation means 103 outputs a local signal having a frequency corresponding to the control signal. Modulating means 104 generates a modulated wave from the baseband signal of the transmission data. The transmission means 105 performs frequency conversion of the modulated wave using the local signal, and transmits a radio wave having a frequency corrected for Doppler shift to the mobile radio communication apparatus 112.

  According to such a wireless communication apparatus, a transmission wave in which a frequency shift due to Doppler shift is corrected in advance is transmitted to the mobile wireless communication apparatus 112. Since the corrected Doppler shift is offset by the Doppler shift of the radio wave propagation path, the mobile radio communication apparatus 112 can receive the radio wave from which the influence of the Doppler shift is eliminated.

  The measurement unit 101 and the control unit 102 correspond to, for example, a radar apparatus 31 and a frequency control circuit 309 in FIG. 3 to be described later, and the frequency variable oscillation unit 103 includes, for example, a transmission unit high frequency band voltage controlled oscillator (VCO) 306 or This corresponds to the transmission unit intermediate frequency band VCO 308. The modulation unit 104 corresponds to, for example, the modulation circuit 310, and the transmission unit 105 includes, for example, the transmission unit high frequency band frequency converter 305 or the transmission unit intermediate frequency band frequency converter 307, the high frequency band transmission amplification circuit 304, and the transmission antenna. 303.

  In the second aspect of the present invention, the wireless communication apparatus includes a measurement unit 101, a control unit 102, a variable frequency oscillation unit 103, a reception unit 106, and a demodulation unit 107, and a mobile wireless communication device installed in a mobile body 111. Receive data from 112.

  The measuring means 101 transmits a radar wave, receives the radar wave reflected by the moving body 111, and measures the Doppler shift frequency. The control means 102 outputs a control signal for correcting the Doppler shift based on the measured frequency, and the frequency variable oscillation means 103 outputs a local signal having a frequency corresponding to the control signal. The receiving means 106 receives a radio wave from the mobile radio communication apparatus 112, performs frequency conversion of the received wave using a local signal, and extracts a modulated component of the received wave whose Doppler shift is corrected. Demodulating means 107 generates a baseband signal of received data from the modulation component of the received wave.

According to such a wireless communication device, when a radio wave affected by the Doppler shift is received from the mobile wireless communication device 112, the frequency shift of the received wave can be corrected.
The measurement unit 101 and the control unit 102 correspond to, for example, a radar apparatus 41 and a frequency control circuit 409 in FIG. 4 described later, respectively, and the variable frequency oscillation unit 103 includes, for example, the reception unit high frequency band VCO 406 or the reception unit intermediate frequency band VCO 408. Corresponding to The reception unit 106 corresponds to, for example, the reception unit high frequency band frequency converter 405 or the reception unit intermediate frequency band frequency converter 407, the high frequency band reception amplification circuit 404, and the reception antenna 403. The demodulation unit 107 includes, for example, a demodulation circuit. Corresponds to 410.

  In the third aspect of the present invention, the wireless communication apparatus includes a measurement unit 101, a control unit 102, a variable frequency oscillation unit 103, a modulation unit 104, a transmission unit 105, a reception unit 106, and a demodulation unit 107, and a mobile unit 111. Data is transmitted / received to / from the mobile wireless communication apparatus 112 installed in the wireless system using a passive method using a frequency-modulated continuous wave.

  The measuring means 101 transmits a radar wave, receives the radar wave reflected by the moving body 111, and measures the Doppler shift frequency and the time from when the radar wave is transmitted until the reflected radar wave is received. To do. The control means 102 outputs a control signal indicating a frequency modulation continuous wave curve for correcting the Doppler shift based on the measured frequency and time, and the variable frequency oscillation means 103 changes according to the control signal. Outputs local signal of frequency.

  Modulating means 104 generates a modulated wave from the baseband signal of the transmission data. The transmission means 105 performs frequency conversion of the modulated wave using the local signal, and transmits a radio wave having a frequency corrected for Doppler shift to the mobile radio communication apparatus 112.

  The receiving means 106 receives a radio wave transmitted from the mobile radio communication apparatus 112 by a passive method, performs frequency conversion of the received wave using the local signal, and extracts a modulated component of the received wave whose Doppler shift is corrected. . Demodulating means 107 generates a baseband signal of received data from the modulation component of the received wave.

  According to such a wireless communication device, a transmission wave in which a frequency shift due to Doppler shift is corrected is transmitted to the mobile wireless communication device 112, and the mobile wireless communication device 112 receives a radio wave that excludes the influence of the Doppler shift. be able to. Furthermore, when a radio wave affected by the Doppler shift is received from the mobile radio communication device 112, the frequency shift of the received wave can be corrected.

  The measurement unit 101, the control unit 102, the frequency variable oscillation unit 103, the modulation unit 104, and the demodulation unit 107 are, for example, a radar device 51, a frequency control circuit 510, a transmission / reception high frequency band VCO 506, a modulation circuit 512, And the demodulation circuit 513, respectively. The transmission unit 105 corresponds to, for example, the high frequency band transmission amplification circuit 504 and the transmission antenna 503, and the reception unit 106 corresponds to, for example, the reception unit high frequency band frequency converter 507, the high frequency band reception amplification circuit 508, and the reception antenna 509. To do.

  In a fourth aspect of the present invention, a wireless communication device includes a measurement unit, a generation unit, a transmission oscillation unit, a modulation unit, and a transmission unit, and transmits data to a mobile wireless communication device installed in a mobile body. To do.

  The measurement means transmits a radar wave, receives the radar wave reflected by the moving body, and measures the Doppler shift frequency. The generation unit generates a low-speed transmission communication packet including information on the measured frequency and a high-speed transmission communication packet including transmission data. The transmission oscillating means outputs a local signal for transmission. The modulation means performs amplitude modulation on the low-speed transmission communication packet at a frequency lower than the carrier wave to generate a modulated wave, and performs multi-level modulation on the high-speed transmission communication packet to generate a modulated wave. The transmission means performs frequency conversion of the generated modulated wave using the local signal for transmission, and transmits the radio wave of the converted frequency to the mobile radio communication device.

The mobile radio communication apparatus includes a reception unit, a demodulation unit, a control unit, a reception frequency variable oscillation unit, and a reception conversion unit, and receives data from other radio communication devices.
The receiving means is multi-valued for a radio wave generated by performing amplitude modulation at a frequency lower than the carrier wave on a low-speed transmission communication packet including information on the Doppler shift frequency of the mobile object and a high-speed transmission communication packet including transmission data Radio waves generated by modulation are received from other wireless communication devices. The demodulating means generates a baseband signal of the low-speed transmission communication packet from the received wave of the low-speed transmission communication packet by envelope detection, and generates a baseband signal of the high-speed transmission communication packet from the modulation component of the reception wave of the high-speed transmission communication packet. .

  The control means extracts Doppler shift frequency information from the baseband signal of the low-speed transmission communication packet, and outputs a reception control signal for correcting the Doppler shift based on the extracted frequency. The reception variable frequency oscillation means outputs a reception local signal having a frequency corresponding to the reception control signal. The reception conversion means performs frequency conversion of the reception wave of the high-speed transmission communication packet using the reception local signal, extracts the modulation component of the reception wave whose Doppler shift is corrected, and outputs it to the demodulation means.

  According to such a mobile radio communication system, first, Doppler shift frequency information is transmitted from the radio communication apparatus to the mobile radio communication apparatus by amplitude modulation with little influence of Doppler shift, and the mobile radio communication apparatus The information can be used to correct the frequency shift of the received wave. Next, transmission data by multi-level modulation influenced by the Doppler shift is transmitted from the wireless communication apparatus to the mobile wireless communication apparatus, and the mobile wireless communication apparatus corrects the frequency shift of the received wave, thereby affecting the influence of the Doppler shift. Can receive radio waves.

  The measurement means corresponds to, for example, a radar apparatus 81 in FIG. 8 or a radar apparatus 1001 in FIG. The generation unit, the modulation unit, the demodulation unit, and the control unit correspond to, for example, the data packet generation circuit 809 or 1019, the modulation circuit 810 or 1020, the demodulation circuit 819 or 1035, and the frequency control circuit 818 or 1042, respectively.

  The transmission oscillating means corresponds to, for example, the transmission unit high frequency band oscillator 806 or the transmission unit intermediate frequency band oscillator 808 of FIG. 8, or the transmission unit high frequency band oscillator 1016 or the transmission unit intermediate frequency band oscillator 1018 of FIG. The transmission means is, for example, the transmission unit high frequency band frequency converter 805 or the transmission unit intermediate frequency band frequency converter 807, the high frequency band transmission amplification circuit 804, and the transmission antenna 803 of FIG. 8, or the transmission unit high frequency band frequency of FIG. This corresponds to the converter 1015 or the transmission unit intermediate frequency band frequency converter 1017, the high frequency band transmission amplifier circuit 1014, and the transmission antenna 1013.

  The reception means corresponds to, for example, the reception antenna 812 and the high frequency band reception amplification circuit 813 of FIG. 8, or the reception antenna 1029 and the high frequency band reception amplification circuit 1030 of FIG. The receiving frequency variable oscillation means corresponds to, for example, the receiving unit high frequency band VCO 815 or the receiving unit intermediate frequency band VCO 817 of FIG. 8, or the receiving unit high frequency band VCO 1032 or the receiving unit intermediate frequency band VCO 1034 of FIG.

  The receiving conversion means is, for example, the receiving unit high frequency band frequency converter 814 or the receiving unit intermediate frequency band frequency converter 816 in FIG. 8, or the receiving unit high frequency band frequency converter 1031 or the receiving unit intermediate frequency band frequency in FIG. This corresponds to the converter 1033.

  According to the present invention, in a mobile radio communication system that transmits and receives data between a master station radio communication device installed on the ground and a slave station radio communication device installed on a mobile object such as a train, By measuring the Doppler shift frequency of a moving object using radar waves, a transmission wave in which the frequency shift due to the Doppler shift is corrected in advance is transmitted from the master station to the slave station, or the frequency shift of the received wave from the slave station is detected at the master station. It becomes possible to correct. It is also possible to transmit information of the measured Doppler shift frequency from the master station to the slave station, and to correct the frequency shift of the received wave from the master station at the slave station.

  As a result, wireless communication that eliminates the influence of the Doppler shift is realized between the master station and the slave station, and the deterioration of the BER caused by the Doppler shift generated according to the speed of the moving body is improved. Further, since a Doppler shift can be corrected without receiving radio waves from a satellite unlike a system using GPS, a train radio communication system suitable for practical use can be constructed.

  In addition, most of the circuits for reducing the influence of Doppler shift can be realized with digital signal processing and inexpensive and easy configuration of modulation and demodulation circuits, enabling downsizing and cost reduction of wireless communication devices. is there.

The best mode for carrying out the present invention will be described below in detail with reference to the drawings.
FIG. 2 is a conceptual diagram of a train radio communication system. In FIG. 2, the ground system includes a master station 21 and a master station control device 22, and the on-board system mounted on the train 25 includes a slave station 23 and a slave station control device 24. V and L represent the relative speed and the relative distance between the master station 21 and the slave station 23, respectively. F1 is the transmission frequency of the radio transmission apparatus provided in the master station 21, F2 is the transmission frequency of the radio transmission apparatus provided in the slave station 23, and F3 is the transmission of the radar apparatus provided in the master station 21. Represents the frequency.

  In the first to fifth train radio communication systems described below, Doppler shift information is calculated using Doppler frequency information measured by the radar device of the master station 21, and the master station 21 is calculated based on the result. The radio frequency used for communication between the slave station 23 and the slave station 23 is corrected.

  In the first train radio communication system, in the unidirectional communication from the master station 21 to the slave station 23, the master station 21 uses the transmitter high frequency band VCO or the transmitter intermediate based on the Doppler frequency information measured by the radar device. The frequency band VCO is controlled, and a transmission wave in which a frequency shift caused by Doppler shift is corrected in advance is output. The corrected Doppler shift is offset by the Doppler shift of the radio wave propagation path, and the slave station 23 receives the received wave having the correct frequency.

  FIG. 3 shows a configuration example of the master station 21 and the slave station 23 in such a first train radio communication system. The system shown in FIG. 3 includes a radar device 31 and a master station radio transmitter 32 installed in the master station 21, and a slave station radio receiver 33 installed in the slave station 23.

  The radar apparatus 31 includes a radar antenna 301 and a Doppler frequency measurement circuit 302. The master station wireless transmission device 32 includes a transmission antenna 303, a high frequency band transmission amplifier circuit 304, a transmission unit high frequency band frequency converter 305, a transmission unit high frequency band VCO 306, a transmission unit intermediate frequency band frequency converter 307, and a transmission unit intermediate frequency band VCO 308. A frequency control circuit 309, a modulation circuit 310, and a baseband processing circuit 311.

  The slave station radio reception apparatus 33 includes a reception antenna 312, a high frequency band reception amplification circuit 313, a frequency converter 314, a reception oscillator 315, a demodulation circuit 316, and a baseband processing circuit 317.

  Next, the operation of the train radio communication system in FIG. 3 will be described. Referring to FIG. 2, since the slave station 23 installed on the train 25 is approaching at a speed V toward the master station 21 installed on the ground, the radio wave of the transmission frequency F1 of the master station radio transmission device 32 is Under the influence of the Doppler effect, the Doppler shift ΔF1 is involved, and F1 + ΔF1 is reached to reach the slave station 23. At this time, if the wavelength of the radio wave having the frequency F1 is λ1, ΔF1 = V / λ1.

  Further, the radio wave of the transmission frequency F3 from the radar device 31 is affected by the Doppler effect, is accompanied by a Doppler shift ΔF3, becomes F3 + ΔF3, reaches the child station 23, is reflected by the train 25, and further receives the Doppler shift ΔF3. Along with this, the master station 21 is reached. For this reason, the frequency of the reflected wave received by the radar apparatus 31 is F3 + 2 × ΔF3. At this time, if the wavelength of the radio wave having the frequency F3 is λ3, ΔF3 = V / λ3.

In this way, the radar antenna 301 outputs a radio wave having the frequency F3 and receives a reflected wave having the frequency F3 + 2 × ΔF3 from the train 25. The Doppler frequency measurement circuit 302 extracts the Doppler shift ΔF3 that changes every moment, and sequentially calculates the relative speed V of the train 25 on which the slave station 23 is mounted. At this time, if the amount of Doppler shift observed by the radar device 31 is ΔFrd (= 2 × ΔF3), the relative velocity V is calculated by the following equation.

V = λ3 × ΔFrd / 2 (1)

Further, the Doppler frequency measurement circuit 302 sequentially calculates the Doppler shift ΔF1 (= V / λ1) of the transmission wave F1 of the master station wireless transmission device 32 using the relative velocity V, and the calculation result is sent to the frequency control circuit 309. Output.

  The frequency control circuit 309 generates a control voltage correction value ΔVF1 so that the Doppler shift amount ΔF1 of the transmission wave F1 is corrected, and outputs the control voltage VLO1-ΔVF1 to the transmission unit high frequency band VCO 306, or the transmission unit The control voltage VLO2-ΔVF1 is output to the intermediate frequency band VCO 308.

  When the control voltage VLO1-ΔVF1 is output to the transmitter high frequency band VCO 306, the control voltage VLO2 is output to the transmitter intermediate frequency band VCO 308, and the control voltage VLO2-ΔVF1 is output to the transmitter intermediate frequency band VCO 308. When outputting, control voltage VLO1 is output with respect to the transmission part high frequency band VCO306.

  When the control voltage VLO1-ΔVF1 is output to the transmission unit high frequency band VCO 306, the transmission unit high frequency band VCO 306 outputs a signal of frequency FLO1-ΔF1, and the transmission unit intermediate frequency band VCO 308 outputs a signal of frequency FLO2. When the control voltage VLO2-ΔVF1 is output to the transmitter intermediate frequency band VCO 308, the transmitter high frequency band VCO 306 outputs a signal of frequency FLO1, and the transmitter intermediate frequency band VCO 308 outputs a signal of frequency FLO2-ΔF1. To do.

  The baseband processing circuit 311 receives transmission data from the master station controller 22, generates a transmission baseband signal and outputs it to the modulation circuit 310, and the modulation circuit 310 generates a modulated wave of transmission data from the transmission baseband signal. And output to the transmitter intermediate frequency band frequency converter 307.

  The transmission unit intermediate frequency band frequency converter 307 converts the modulated wave into the intermediate frequency FIF (or FIF-ΔF1) using the output FLO2 (or FLO2-ΔF1) of the transmission unit intermediate frequency band VCO 308 as a local signal. The transmission unit high frequency band frequency converter 305 uses the output FLO1-ΔF1 (or FLO1) of the transmission unit high frequency band VCO 306 as a local signal, and transmits the output of the intermediate frequency FIF (or FIF-ΔF1) with the Doppler shift ΔF1 corrected. The frequency is converted to F1-ΔF1.

The high frequency band transmission amplifier circuit 304 amplifies the transmission wave having the frequency F 1 −ΔF 1, and the transmission antenna 303 transmits the amplified transmission wave to the slave station radio reception apparatus 33.
The transmission wave F1-ΔF1 from the master station wireless transmission device 32 is affected by the Doppler shift in the radio wave propagation path, thereby canceling out the Doppler shift amount ΔF1. Therefore, the reception wave of frequency F1 is input to the reception antenna 312 of the slave station radio reception apparatus 33. The reception wave F1 is amplified by the high frequency band reception amplification circuit 313 and output to the frequency converter 314.

  The frequency converter 314 frequency-converts the output of the high frequency band reception amplification circuit 313 using the output of the reception oscillator 315 as a local signal. Demodulation circuit 316 extracts the received baseband signal with the Doppler shift ΔF1 corrected from the frequency-converted received signal, and outputs the received baseband signal to baseband processing circuit 317. The baseband processing circuit 317 extracts received data from the received baseband signal and transfers it to the slave station control device 24.

  That is, the slave station radio reception apparatus 33 receives the radio wave with the corrected Doppler shift ΔF1 to extract a reception baseband signal with little signal degradation due to the Doppler shift ΔF1, and the data without BER degradation. Can be demodulated.

  As described above, according to the train radio communication system of FIG. 3, in the unidirectional communication from the master station 21 to the slave station 23, the Doppler shift amount ΔFrd of the transmission / reception wave of the radar device 31 to the Doppler shift amount of the transmission wave F1. By sequentially calculating ΔF1, the Doppler shift ΔF1 can be easily corrected in real time, so that stable communication quality can be ensured.

  In the master station 21, most of the circuits for calculating and correcting the Doppler shift ΔF1 can be realized by digital signal processing. In the slave station 23, a special correction for correcting the Doppler shift of the transmission wave F1 is possible. Does not require a simple circuit.

  Next, the second train radio communication system will be described. In the second train radio communication system, in the unidirectional communication from the slave station 23 to the master station 21, the master station 21 receives the reception high frequency band VCO or the reception intermediate frequency band based on the Doppler frequency information measured by the radar device. The VCO is controlled to correct the frequency shift due to the Doppler shift of the received wave.

  FIG. 4 shows a configuration example of the master station 21 and the slave station 23 in such a train radio communication system. The system shown in FIG. 4 includes a radar device 41 and a master station radio receiver 42 installed in the master station 21, and a slave station radio transmitter 43 installed in the slave station 23.

  The radar apparatus 41 includes a radar antenna 401 and a Doppler frequency measurement circuit 402. The master station radio receiver 42 includes a reception antenna 403, a high frequency band reception amplification circuit 404, a reception unit high frequency band frequency converter 405, a reception unit high frequency band VCO 406, a reception unit intermediate frequency band frequency converter 407, and a reception unit intermediate frequency band VCO 408. A frequency control circuit 409, a demodulation circuit 410, and a baseband processing circuit 411.

  The slave station radio transmission apparatus 43 includes a transmission antenna 412, a high frequency band transmission amplifier circuit 413, a frequency converter 414, a transmission oscillator 415, a modulation circuit 416, and a baseband processing circuit 417.

  Next, the operation of the train radio communication system in FIG. 4 will be described. In this system, the master station radio receiver 42 controls the reception local signal that is the output of the receiver high frequency band VCO 406 or the receiver intermediate frequency band VCO 408, and transmits the transmission wave of the frequency F 2 from the slave station radio transmitter 43. The Doppler shift amount ΔF2 is corrected.

  The baseband processing circuit 417 of the slave station wireless transmission device 43 receives transmission data from the slave station control device 24, generates a transmission baseband signal, and outputs it to the modulation circuit 416. The modulation circuit 416 receives the transmission baseband signal from the transmission baseband signal. A modulated wave of transmission data is generated and output to the frequency converter 414.

  The frequency converter 414 uses the output of the frequency F2 from the transmission oscillator 415 as a local signal, converts the modulated wave of the transmission data into a high frequency band signal, and the high frequency band transmission amplifier circuit 413 amplifies the transmission wave of the frequency F2. Then, the transmission antenna 412 transmits the amplified transmission wave to the master station radio reception device 42.

  Similarly to the radar apparatus 31 of FIG. 3, the radar apparatus 41 outputs a radio wave having a frequency F3, and sequentially calculates the relative speed V of the slave station 23 from the Doppler shift amount ΔFrd (= 2 × ΔF3). Then, the relative speed V is used to sequentially calculate the Doppler shift ΔF2 of the transmission wave F2 of the slave station wireless transmission device 43, and the calculation result is output to the frequency control circuit 409.

  The frequency control circuit 409 generates a control voltage correction value ΔVF2 so that the Doppler shift amount ΔF2 of the transmission wave F2 is corrected, and outputs the control voltage VLO1-ΔVF2 to the reception unit high frequency band VCO 406, or receives the reception unit A control voltage VLO2-ΔVF2 is output to the intermediate frequency band VCO 408.

  When the control voltage VLO1-ΔVF2 is output to the receiver high frequency band VCO 406, the control voltage VLO2 is output to the receiver intermediate frequency band VCO 408, and the control voltage VLO2-ΔVF2 is output to the receiver intermediate frequency band VCO 408. When outputting, control voltage VLO1 is output with respect to the receiving part high frequency band VCO406.

  When the control voltage VLO1-ΔVF2 is output to the receiver high frequency band VCO 406, the receiver high frequency band VCO 406 outputs a signal of frequency FLO1-ΔF2, and the receiver intermediate frequency band VCO 408 outputs a signal of frequency FLO2. When the control voltage VLO2-ΔVF2 is output to the receiver intermediate frequency band VCO 408, the receiver high frequency band VCO 406 outputs a signal of frequency FLO1, and the receiver intermediate frequency band VCO 408 outputs a signal of frequency FLO2-ΔF2. To do.

  Since the transmission wave F2 from the slave station wireless transmission device 43 is affected by the Doppler shift in the radio wave propagation path, the reception wave having the frequency F2 + ΔF2 is input to the reception antenna 403. The reception wave F2 + ΔF2 is amplified by the high frequency band reception amplification circuit 404 and output to the reception unit high frequency band frequency converter 405.

  The reception unit high frequency band frequency converter 405 converts the output from the high frequency band reception amplification circuit 404 into an intermediate frequency FIF (or FIF + ΔF2) using the output FLO1-ΔF2 (or FLO1) of the reception unit high frequency band VCO 406 as a local signal. The receiver intermediate frequency band frequency converter 407 converts the output of the intermediate frequency FIF (or FIF + ΔF2) using the output FLO2 (or FLO2-ΔF2) of the receiver intermediate frequency band VCO 408 as a local signal, and the Doppler shift ΔF2 is The modulated component of the received wave having the corrected frequency F2 is extracted.

  Demodulation circuit 410 extracts the received baseband signal from the modulation component of the received wave, and outputs it to baseband processing circuit 411. The baseband processing circuit 411 extracts received data from the received baseband signal and transfers it to the master station control device 22.

  That is, the master station radio receiving apparatus 42 can generate a local signal that corrects the Doppler shift ΔF2 by controlling the receiving unit high frequency band VCO 406 or the receiving unit intermediate frequency band VCO 408 by the frequency control circuit 409. . By using this local signal to remove the Doppler shift amount ΔF2 of the received wave F2 + ΔF2 affected by the Doppler shift, a received baseband signal with little signal degradation due to the Doppler shift ΔF2 is extracted, and BER degradation occurs. Data can be demodulated without any problem.

  As described above, according to the train radio communication system of FIG. 4, in the unidirectional communication from the slave station 23 to the master station 21, the transmission wave (from the Doppler shift ΔFrd of the transmission / reception wave of the radar device 41 to the slave station 23 ( That is, by sequentially calculating the Doppler shift amount ΔF2 of the received wave of the master station 21, correction of the Doppler shift amount ΔF2 of the received wave of the master station 21 can be easily performed in real time, so that stable communication quality can be ensured.

  In the master station 21, most of the circuits for calculating and correcting the Doppler shift ΔF2 can be realized by digital signal processing. In the slave station 23, a special correction for correcting the Doppler shift of the transmission wave F2 is possible. Does not require a simple circuit.

  Next, the third train radio communication system will be described. In the third train radio communication system, half duplex bidirectional communication using a passive method is performed between the master station 21 and the slave station 23. The master station 21 controls the transmission / reception VCO based on the Doppler frequency information measured by the radar device, outputs a transmission wave in which a frequency shift caused by the Doppler shift is corrected in advance, and depends on the Doppler frequency of the reception wave. Correct frequency deviation.

  FIG. 5 shows a configuration example of the master station 21 and the slave station 23 in such a train radio communication system. The system shown in FIG. 5 includes a radar device 51 and a master station radio transmission / reception device 52 installed in the master station 21, and a slave station radio transmission / reception device 53 installed in the slave station 23.

  The radar apparatus 51 includes a radar antenna 501 and a Doppler frequency / relative distance measurement circuit 502. The master station radio transmission / reception device 52 includes a transmission antenna 503, a high frequency band transmission amplification circuit 504, a transmission / reception high frequency band VCO 506, a reception unit high frequency band frequency converter 507, a high frequency band reception amplification circuit 508, a reception antenna 509, a frequency control circuit 510, A memory 511, a modulation circuit 512, a demodulation circuit 513, and a baseband processing circuit 514 are provided.

  The slave station radio transmission / reception apparatus 53 includes a reception antenna 515, a high frequency band reception amplification circuit 516, a signal distributor 517, a high frequency band transmission amplification circuit 519, a transmission antenna 520, a demodulation circuit 521, a modulation circuit 522, and a baseband processing circuit 523. Prepare.

  FIG. 6 is a graph showing changes in frequency in the train radio communication system of FIG. In FIG. 6, a broken line 531 represents a frequency change of a signal (transmission wave frequency F <b> 1) output from the transmission / reception high-frequency band VCO 506 of the parent station wireless transmission / reception device 52, and a solid line 532 is received by the parent station wireless transmission / reception device 52. A change in frequency of radio waves is represented, and a one-dot chain line 533 represents a change in frequency of radio waves received by the slave station wireless transmission / reception device 53.

  t1 represents the radio wave propagation delay time due to the relative distance between the master station 21 and the slave station 23, and t3 represents the round-trip radio wave propagation delay time due to the relative distance between the master station 21 and the slave station 23. t2 represents the packet transmission time from the parent station 21 to the child station 23, and t4 represents the packet transmission time from the child station 23 to the parent station 21. ΔF1 is a Doppler shift that occurs when the slave station 23 receives a packet, and 2 × ΔF1 is a Doppler shift that occurs when the master station 21 receives a packet.

  In packet transmission from the master station radio transceiver apparatus 52 to the slave station radio transceiver apparatus 53 at time t2, the modulation circuit 512 of the master station radio transceiver apparatus 52 generates an amplitude modulation (AM modulation) signal, and the high frequency transmission amplifier circuit 504 The drive voltage is turned ON / OFF. As a result, a high frequency band AM-modulated wave is output from the master station radio transceiver apparatus 52, and the demodulation circuit 521 of the slave station radio transceiver apparatus 53 extracts packets using the envelope detection method.

  When the slave station radio transceiver 53 receives a packet from the master station radio transceiver 52, a Doppler shift ΔF1 occurs in the carrier wave, but AM modulation is performed in a frequency band far lower than the carrier wave, and an envelope detection method is used. Therefore, even if the Doppler shift ΔF1 occurs in the carrier band, the Doppler shift amount is very small in the reception baseband. Therefore, it is possible to extract a received baseband signal with little signal degradation and to demodulate data without causing BER degradation.

  On the other hand, in packet transmission from the slave station radio transceiver apparatus 52 to the master station radio transceiver apparatus 52 at time t4, the frequency control circuit 510 and the memory 511 are set based on the Doppler frequency and the relative distance L measured by the radar apparatus 51. By using this and controlling the transmission / reception high frequency band VCO 506, the master station radio transmission / reception device 52 outputs FM-CW transmission waves in which the Doppler shift 2 × ΔF 1 is corrected in advance.

  The slave station radio transceiver 53 returns the received FM-CW signal in a passive manner and supplies it as a local signal to the high frequency band transmission amplifier 519, and the modulation circuit 522 generates an FSK (Frequency shift keying) / AM modulation signal. Then, the drive voltage of the high-frequency transmission amplifier circuit 519 is turned ON / OFF in accordance with the frequency of FSK. As a result, the FSK / AM modulated wave in the high frequency band is output from the slave station radio transceiver 53.

  The reception unit high frequency band frequency converter 507 of the master station radio transceiver 52 outputs FM-CW output from the transmission / reception high frequency band VCO 507 controlled to correct the Doppler shift 2 × ΔF1 when performing the detection by the homodyne method. The signal is used as a local signal. Therefore, it is possible to extract a received baseband signal with little signal degradation and to demodulate data without causing BER degradation.

By the way, in the memory 511 of the master station radio transmission / reception apparatus 52, for example, as shown in FIG. 7, a matrix structure area is prepared in which the axis of the relative distance L and the axis of the relative velocity V are taken. FM-CW curve data corresponding to the set is stored. This FM-CW curve is digital data that can be converted from digital to analog, and its slope k is calculated in advance by the following equation using relative velocity V and relative distance L as parameters.

k = (V × C) / (L × λ) (2)

Here, C represents the speed of light, and λ represents the wavelength of the transmission wave of the master station radio transceiver apparatus 52.

  At time t4, the Doppler frequency / relative distance measuring circuit 502 of the master station radio transmitting / receiving device 52 sequentially calculates the relative speed V and relative distance L of the slave station 23 that change from moment to moment, and outputs them to the frequency control circuit 510. To do. The frequency control circuit 510 reads the FM-CW curve corresponding to the received set of the relative velocity V and the relative distance L from the memory 511, converts it into a control voltage, and outputs it to the transmission / reception high frequency band VCO 506. Thereby, it is possible to make the frequency change 531 of the transmission / reception high frequency band VCO 506 coincide with the frequency change 532 of the received wave of the master radio transmission / reception apparatus 52.

  Next, the operation of the train radio communication system in FIG. 5 will be described. In this system, when packet transmission is performed from the master station radio transmitter / receiver 52 to the slave station radio transmitter / receiver 53, the baseband processing circuit 514 receives transmission data from the master station controller 22 and generates a transmission baseband signal. The modulation circuit 512 generates an AM modulation signal of transmission data from the transmission baseband signal and outputs it to the high frequency band transmission amplification circuit 504.

  The high frequency band transmission amplifier circuit 504 controls the drive voltage on / off by the AM modulation signal from the modulation circuit 512 and outputs a high frequency band AM modulated wave, and the transmission antenna 503 transmits / receives the AM modulated wave to / from the local station wirelessly. Transmit to the device 53.

  Since the transmission wave F1 of the master station radio transmission / reception device 52 is affected by the Doppler shift in the radio wave propagation path, a Doppler shift amount ΔF1 is generated, and the reception wave F1 + ΔF1 is input to the reception antenna 515 of the slave station radio transmission / reception device 53. The The reception wave F1 + ΔF1 is amplified by the high frequency band reception amplification circuit 516 and output to the demodulation circuit 521 through the signal distributor 517.

  Demodulation circuit 521 demodulates the received wave using the envelope detection method, and outputs the received baseband signal to baseband processing circuit 523. The baseband processing circuit 523 extracts received data from the received baseband signal and transfers it to the slave station control device 24.

  That is, since the master station radio transmitter / receiver 52 performs AM modulation in a frequency band far lower than the carrier wave and the slave station radio transmitter / receiver 53 performs demodulation using the envelope detection method, a Doppler shift ΔF1 occurs in the carrier wave band. However, the Doppler shift amount is very small in the reception baseband.

On the other hand, when packet transmission is performed from the slave station radio transceiver 53 to the master station radio transceiver 52, the radar device 51 outputs radio waves of the frequency F3 as in the radar device 31 of FIG. ΔFrd (= 2 × ΔF3) and a time t3 from when the radio wave is transmitted to when the reflected wave is received are measured. The Doppler frequency / relative distance measuring circuit 502 sequentially calculates the relative speed V of the slave station 23 from the Doppler shift amount ΔFrd, and sequentially calculates the relative distance L of the slave station 23 from the time t3 by the following equation.

L = t3 × C / 2 (3)

The calculated relative velocity V and relative distance L are output to the frequency control circuit 510 of the master station radio transmitting / receiving device 52, and the frequency control circuit 510 reads FM-CW curves corresponding to these numerical sets from the memory 511. Thus, a control voltage for correcting the Doppler shift amount 2 × ΔF1 is generated.

  The transmission / reception high-frequency band VCO 506 is controlled by this control voltage and outputs a local signal having a frequency FLO subjected to FM-CW modulation. The local signal FLO is transmitted as a transmission wave F1 to the slave station radio transmission / reception device 53 via the high-frequency band transmission amplifier circuit 504 and the transmission antenna 503.

At this time, if the relative velocity V in the equation (2) is replaced with λ × ΔF1 and the relative distance L is replaced with t3 × C / 2 in the equation (3), the slope k of the FM-CW curve becomes as follows. .

k = 2 × ΔF1 / t3 (4)

Therefore, it can be seen that the local signal FLO of the transmission / reception high frequency band VCO 506 is controlled such that the frequency increases by 2 × ΔF1 during the radio wave propagation delay time t3.

  Since the transmission wave F1 of the master station radio transmission / reception device 52 is affected by the Doppler shift in the radio wave propagation path, a Doppler shift amount ΔF1 occurs, and the reception wave F2 = F1 + ΔF1 is generated in the reception antenna 515 of the slave station radio transmission / reception device 53. Entered. The reception wave F2 is amplified by the high frequency band reception amplification circuit 516 and supplied as a local signal to the high frequency band transmission amplification circuit 519 via the signal distributor 517.

  The baseband processing circuit 523 receives transmission data from the slave station controller 24, generates a transmission baseband signal, and outputs the transmission baseband signal to the modulation circuit 522. The modulation circuit 522 performs FSK / AM modulation of the transmission data from the transmission baseband signal. A signal is generated and output to the high frequency band transmission amplifier circuit 519. The high-frequency transmission amplifier circuit 519 controls the driving voltage according to the frequency of the FSK by the FSK / AM modulation signal from the modulation circuit 522, outputs a high-frequency band FSK / AM modulated wave, and the transmission antenna 520 The transmission wave of the frequency F2 is transmitted to the master station radio transmission / reception device 52.

  Since the transmission wave F2 of the child base station radio transmission / reception device 53 is affected by the Doppler shift in the radio wave propagation path, a Doppler shift amount ΔF1 is generated, and the reception wave F2 + ΔF1 = F1 + 2 is generated in the reception antenna 509 of the parent station radio transmission / reception device 52. × ΔF1 is input.

  The high frequency band reception amplification circuit 508 amplifies the reception wave F1 + 2 × ΔF1 and outputs the amplified signal to the reception unit high frequency band frequency converter 507. The receiving unit high frequency band frequency converter 507 performs homodyne detection of the received wave using the FM-CW modulated local signal FLO output from the transmission / reception high frequency band VCO 506 to extract a modulation component. Demodulation circuit 513 extracts the received baseband signal from the modulation component of the received wave, and outputs it to baseband processing circuit 514. The baseband processing circuit 514 extracts received data from the received baseband signal and transfers it to the master station controller 22.

  At the time when the received wave F1 + 2 × ΔF1 is homodyne detected by the receiving unit high frequency band frequency converter 507, the round-trip radio wave propagation delay time t3 between the master station 21 and the slave station 23 has passed. The frequency of the output local signal FLO changes from F1 to F1 + 2 × ΔF1. For this reason, the frequency change 2 × ΔF1 of the local signal FLO and the Doppler shift 2 × ΔF1 are canceled out.

  When the frequency control circuit 510 outputs the control voltage, instead of using the memory 511 storing the FM-CW curve data, the slope k of the FM-CW curve is calculated in real time using the equation (2). Also good.

  As described above, according to the train radio communication system of FIG. 5, in the bidirectional communication performed in a passive manner between the master station 21 and the slave station 23, the child wave is detected from the Doppler shift amount ΔFrd of the transmission / reception wave of the radar device 51. The relative speed V and the relative distance L of the station 23 are calculated, FM-CW curves corresponding to them are read from the memory, and the transmission / reception high frequency band VCO 506 is sequentially controlled. Thereby, the correction of the Doppler shift 2 × ΔF1 of the transmission / reception wave of the master station 21 can be easily performed in real time, so that stable communication quality can be ensured.

  In the master station 21, most of the control circuit for correcting the amount of Doppler shift can be realized by digital signal processing. Further, since it is a passive communication, the transmission / reception frequency is the same, and the local signal for transmission / reception is transmitted. Only one VCO needs to be generated. The slave station 23 does not require a high-frequency band oscillator and does not require a special circuit for correcting the Doppler shift 2 × ΔF1 of the transmitted / received wave.

  Next, the fourth train radio communication system will be described. In the fourth train radio communication system, in the unidirectional communication from the master station 21 to the slave station 23, the master station 21 generates a data packet including Doppler frequency information measured by the radar device, and the influence of the Doppler shift. After low-speed data transmission is performed with low AM modulation and the frequency of the received wave can be corrected on the slave station 23 side, the transmission wave is output by switching to high-speed data transmission by multilevel modulation.

  On the other hand, the slave station 23 extracts the Doppler frequency information from the demodulated data by the envelope detection and controls the receiving unit high frequency band VCO or the receiving unit intermediate frequency band VCO, thereby correcting the frequency shift due to the Doppler shift of the receiving wave. Thereafter, the multi-level modulated high-speed data is demodulated using the heterodyne method or the superheterodyne method. As a result, communication is performed from the master station 21 to the slave station 23 in which the Doppler shift is corrected.

  FIG. 8 shows a configuration example of the master station 21 and the slave station 23 in such a fourth train radio communication system. The system of FIG. 8 includes a radar device 81 and a master station radio transmission device 82 installed in the master station 21, and a slave station radio reception device 83 installed in the slave station 23.

  The radar device 81 includes a radar antenna 801 and a Doppler frequency measurement circuit 802. The master station wireless transmission device 82 includes a transmission antenna 803, a high frequency band transmission amplifier circuit 804, a transmission unit high frequency band frequency converter 805, a transmission unit high frequency band oscillator 806, a transmission unit intermediate frequency band frequency converter 807, and a transmission unit intermediate frequency band. An oscillator 808, a data packet generation circuit 809, a modulation circuit 810, and a baseband processing circuit 811 are provided.

  The slave station radio reception device 83 includes a reception antenna 812, a high frequency band reception amplification circuit 813, a reception unit high frequency band frequency converter 814, a reception unit high frequency band VCO 815, a reception unit intermediate frequency band frequency converter 816, and a reception unit intermediate frequency band VCO 817. A frequency control circuit 818, a demodulation circuit 819, and a baseband processing circuit 820.

  FIG. 9 shows an example of the structure and timing of a communication packet used in the train radio communication system of FIG. As shown in the communication packet timing configuration 91, N low-speed transmission communication packets 92 are first transmitted from the master station 21 to the slave station 23, and then M high-speed transmission communication packets 93 are transmitted. Thereafter, data transmission is performed using these N + M packets as a reference period.

  The low-speed transmission communication packet 92 includes synchronization data 901 for timing synchronization at the time of reception, control data 902 including Doppler shift information, and an error detection code 903. The high-speed transmission communication packet 93 includes synchronization data 904 for timing synchronization at the time of reception, control data 905 including Doppler shift information, information data 906, and an error detection code 907.

  Next, the operation of the train radio communication system in FIG. 8 will be described. In this system, the master station wireless transmission device 82 converts a low-speed transmission communication packet 92 including Doppler shift information into an AM modulated wave that is less affected by Doppler shift, and then transmits the high-speed transmission communication packet 93 with multi-level modulation. Convert to wave and send.

  The slave station radio reception device 83 extracts Doppler shift information from the received wave subjected to AM modulation by envelope detection, performs frequency control, and corrects the Doppler shift for the received wave subjected to multilevel modulation. By doing so, the high-speed transmission communication packet 93 is normally received. In the slave station radio receiver 83, a superheterodyne system is used for demodulation of high-speed data.

  Similarly to the radar apparatus 31 of FIG. 3, the radar apparatus 81 outputs a radio wave having a frequency F3, and sequentially calculates the relative speed V of the slave station 23 from the Doppler shift amount ΔFrd (= 2 × ΔF3). Then, using the relative velocity V, the Doppler shift ΔF1 of the transmission wave F1 of the master station radio transmitter 82 is sequentially calculated, and the calculation result is output to the master station radio transmitter 82.

  The data packet generation circuit 809 of the master station wireless transmission device 82 includes the calculation result for the Doppler shift in the control data 902 and 905, and in the time series shown in the timing configuration 91 of the communication packet, the low-speed transmission communication packet 92 and the high-speed transmission packet 92 A transmission communication packet 93 is generated. When the high-speed transmission communication packet 93 is generated, transmission data is received from the master station control device 22 and used as information data 906.

  The baseband processing circuit 811 receives a communication packet from the data packet generation circuit 809, generates a transmission baseband signal, and outputs it to the modulation circuit 810. Modulation circuit 810 generates a modulated wave of transmission data from the transmission baseband signal and outputs the modulated wave to transmission unit intermediate frequency band frequency converter 807. At this time, the low-speed transmission communication packet 92 is AM-modulated in a frequency band far lower than the carrier wave and converted into an AM-modulated wave, and the high-speed transmission communication packet 93 is converted into a multi-level modulated wave.

  The transmission unit intermediate frequency band frequency converter 807 converts the modulated wave into the intermediate frequency FIF using the local signal of the frequency FLO2 output from the transmission unit intermediate frequency band oscillator 808. The transmission unit high frequency band frequency converter 805 converts the output of the intermediate frequency FIF to the transmission frequency F1 using the local signal of the frequency FLO1 output from the transmission unit high frequency band oscillator 806. The high-frequency band transmission amplifier circuit 804 amplifies the transmission wave of the frequency F1, and the transmission antenna 803 transmits the amplified transmission wave to the slave station radio reception device 83.

  The transmission wave F1 from the master station radio transmission apparatus 82 is affected by the Doppler shift in the radio wave propagation path, and the reception wave of the frequency F1 + ΔF1 is input to the reception antenna 812 of the slave station radio reception apparatus 83.

  The reception wave subjected to AM modulation is amplified by the high frequency band reception amplification circuit 813 and output to the demodulation circuit 819. Demodulation circuit 819 demodulates the received wave by envelope detection and outputs the received baseband signal to baseband processing circuit 820. The baseband processing circuit 820 reproduces the low-speed transmission communication packet 92 from the received baseband signal, extracts Doppler shift information from the control data 902, and sequentially outputs it to the frequency control circuit 818.

  The frequency control circuit 818 generates a control voltage for correcting the Doppler shift ΔF1 from the Doppler shift information, the frequency of the reception unit high frequency band VCO 815 is FLO1-ΔF1, and the frequency of the reception unit intermediate frequency band VCO 817 is FLO2. Alternatively, control is performed so that the frequency of the receiver intermediate frequency band VCO 817 becomes FLO2−ΔF1 and the frequency of the receiver high frequency band VCO 815 becomes FLO1.

  On the other hand, the received wave subjected to multilevel modulation is amplified by a high frequency band reception amplification circuit 813 and output to the reception unit high frequency band frequency converter 814. The receiving unit high frequency band frequency converter 814 converts the frequency of the received wave using the output FLO1-ΔF1 (or FLO1) of the receiving unit high frequency band VCO 815 as a local signal, and the receiving unit intermediate frequency band frequency converter 816 includes the receiving unit intermediate frequency band frequency converter 816. Using the output FLO2 (or FLO2-ΔF1) of the frequency band VCO 817 as a local signal, the output of the receiving unit high frequency band frequency converter 814 is frequency converted.

  As a result, the multilevel modulation component of the received wave with the Doppler shift ΔF1 corrected is extracted. The demodulation circuit 819 extracts a received baseband signal that is less deteriorated due to the Doppler shift ΔF1 from the multilevel modulation component, and demodulates the data without causing BER deterioration.

  The baseband processing circuit 820 reproduces the high-speed transmission communication packet 93 from the received baseband signal, extracts Doppler shift information from the control data 905, and sequentially outputs it to the frequency control circuit 818. As a result, the frequency control circuit 818 can correct the Doppler shift ΔF1 that changes depending on the moving speed of the slave station 23 in real time. Further, the baseband processing circuit 820 extracts the information data 906 of the high-speed transmission communication packet 93 and transfers it to the slave station control device 24.

  In the communication packet timing configuration 91, since the N low-speed transmission communication packets 92 and the M high-speed transmission communication packets 93 are alternately transmitted at a constant period, the slave station 23 can transmit the master station 21 at an arbitrary timing. Even when the communication area is reached, the low-speed transmission communication packet 92 can be received at a constant period to correct the Doppler shift.

  As described above, according to the train radio communication system of FIG. 8, in the unidirectional communication from the master station 21 to the slave station 23, the Doppler shift amount ΔFrd of the transmission / reception wave of the radar device 81 to the Doppler shift amount of the transmission wave F1. ΔF1 is sequentially calculated, and the master station wireless transmission device 82 periodically and alternately transmits a low-speed transmission communication packet based on AM modulation and a high-speed transmission communication packet based on multi-level modulation including information of Doppler shift ΔF1. As a result, the slave station radio reception device 83 can easily correct the Doppler shift ΔF1 in real time, so that stable communication quality can be ensured.

  In the master station wireless transmission device 82, most of the circuits that calculate the Doppler shift ΔF1 and generate the low-speed transmission communication packet 92 and the high-speed transmission communication packet 93 can be realized by digital signal processing. The AM modulation circuit can be easily and inexpensively configured. In the slave station wireless reception device 83, the envelope detection circuit can be easily and inexpensively configured.

  Next, a fifth train radio communication system will be described. In the fifth train radio communication system, in addition to the configuration of the fourth train radio communication system, the master station 21 has a configuration for demodulating multi-level modulated high-speed data using a heterodyne system or a superheterodyne system. The slave station 23 controls the transmission unit high frequency band VCO or the transmission unit intermediate frequency band VCO with a configuration for generating a multi-level modulation signal for high-speed data transmission and a frequency control signal corrected for Doppler shift, and transmits the transmission wave. And a configuration for transmitting. Thus, transmission from the slave station 23 to the master station 21 with the Doppler shift corrected is realized.

  FIG. 10 shows a configuration example of the master station 21 and the slave station 23 in such a fifth train radio communication system. The system in FIG. 10 includes a radar apparatus 1001 and a master station radio transmission / reception apparatus 1002 installed in the master station 21, and a slave station radio transmission / reception apparatus 1003 installed in the slave station 23.

  The master station radio transmission / reception device 1002 has a configuration in which a reception circuit for a received wave subjected to multilevel modulation is added to the circuit configuration of the master station radio transmission device 82 in FIG. 8 has a configuration in which a transmission circuit of a transmission wave subjected to multi-level modulation is added to the circuit configuration of the eight slave station radio reception apparatuses 83. In the master station radio transmission / reception apparatus 1002, a superheterodyne system is used for demodulation of high-speed data.

  The radar apparatus 1001 includes a radar antenna 1011 and a Doppler frequency measurement circuit 1012. The master station radio transceiver 1002 includes a transmission antenna 1013, a high frequency band transmission amplifier circuit 1014, a transmission unit high frequency band frequency converter 1015, a transmission unit high frequency band oscillator 1016, a transmission unit intermediate frequency band frequency converter 1017, and a transmission unit intermediate frequency band. Oscillator 1018, data packet generation circuit 1019, modulation circuit 1020, reception antenna 1021, high frequency band reception amplification circuit 1022, reception unit high frequency band frequency converter 1023, reception unit high frequency band oscillator 1024, reception unit intermediate frequency band frequency converter 1025, A receiving unit intermediate frequency band oscillator 1026, a demodulation circuit 1027, and a baseband processing circuit 1028 are provided.

  The slave station radio transmission / reception device 1003 includes a reception antenna 1029, a high frequency band reception amplification circuit 1030, a reception unit high frequency band frequency converter 1031, a reception unit high frequency band VCO 1032, a reception unit intermediate frequency band frequency converter 1033, and a reception unit intermediate frequency band VCO 1034. , Demodulation circuit 1035, transmission antenna 1036, high frequency band transmission amplifier circuit 1037, transmission unit high frequency band frequency converter 1038, transmission unit high frequency band VCO 1039, transmission unit intermediate frequency band frequency converter 1040, transmission unit intermediate frequency band VCO 1041, frequency control A circuit 1042, a modulation circuit 1043, and a baseband processing circuit 1044 are provided.

  Next, the operation of the train radio communication system in FIG. 10 will be described. In this system, in the bidirectional communication performed between the master station 21 and the slave station 23, in addition to correcting the Doppler shift amount ΔF1 of the transmission wave F1 of the master station 21, the Doppler shift amount of the transmission wave F2 of the slave station 21 is corrected. ΔF2 is also corrected.

  The operation of transmitting the transmission wave F1 from the master station 21 to the slave station 23 and the operation of correcting the Doppler shift ΔF1 in the slave station 23 are the same as in the case of FIG. At this time, the low-speed transmission communication packet 92 and the high-speed transmission communication packet 93 shown in FIG. 9 are used.

  When transmitting the transmission wave F2 from the slave station 23 to the master station 21, the baseband processing circuit 1044 of the slave station wireless transmission / reception device 1003 receives the high-speed transmission communication packet 93 from the slave station control device 24 and generates a transmission baseband signal. And output to the modulation circuit 1043. Modulation circuit 1043 generates a multi-level modulated wave from the transmission baseband signal and outputs it to transmitter intermediate frequency band frequency converter 1040.

  Also, the baseband processing circuit 1044 extracts Doppler shift information from the received communication packet and sequentially outputs it to the frequency control circuit 1042. The frequency control circuit 1042 generates a control voltage for correcting the Doppler shift ΔF2 from the Doppler shift information, the frequency of the transmission unit high frequency band VCO 1039 is FLO3-ΔF2, and the frequency of the transmission unit intermediate frequency band VCO 1041 is FLO4. Alternatively, control is performed so that the frequency of the transmission unit intermediate frequency band VCO 1041 becomes FLO4-ΔF2 and the frequency of the transmission unit high frequency band VCO 1039 becomes FLO3.

  At this time, the frequency control circuit 1042 converts the Doppler shift ΔF1 of the transmission wave F1 into the Doppler shift ΔF2 of the transmission wave F2 via the relative speed V, thereby transmitting the transmission unit high frequency band VCO 1039 and the transmission unit intermediate frequency band. A control voltage for the VCO 1041 is generated.

  The transmitter intermediate frequency band frequency converter 1040 converts the multi-level modulated wave into an intermediate frequency using the output FLO4-ΔF2 (or FLO4) of the transmitter intermediate frequency band VCO 1041 as a local signal. Transmitter high frequency band frequency converter 1038 converts output FLO3 (or FLO3-ΔF2) of transmitter high frequency band VCO 1039 as a local signal and converts the output of the intermediate frequency to transmission frequency F2-ΔF2 in which Doppler shift ΔF2 is corrected. .

The high frequency band transmission amplifier circuit 1037 amplifies the transmission wave having the frequency F 2 −ΔF 2, and the transmission antenna 1036 transmits the amplified transmission wave to the master station radio transmission / reception apparatus 1002.
The transmission wave F2-ΔF2 from the slave station radio transmitting / receiving apparatus 1003 is affected by the Doppler shift in the radio wave propagation path, so that the Doppler shift ΔF2 is canceled. Therefore, the reception wave of frequency F2 is input to the reception antenna 1021 of the master station radio transceiver apparatus 1002. The reception wave F2 is amplified by the high frequency band reception amplification circuit 1022 and output to the reception unit high frequency band frequency converter 1023.

  The receiving unit high frequency band frequency converter 1023 frequency-converts the received wave using the output FLO3 of the receiving unit high frequency band oscillator 1024 as a local signal, and the receiving unit intermediate frequency band frequency converter 1025 Using the output FLO4 as a local signal, the output of the receiving unit high frequency band frequency converter 1023 is frequency converted.

  As a result, the multilevel modulation component of the received wave with the Doppler shift amount ΔF2 corrected is extracted. The demodulation circuit 1027 extracts a received baseband signal that is less deteriorated due to the Doppler shift ΔF2 from the multilevel modulation component, and demodulates the data without causing BER deterioration. The baseband processing circuit 1028 reproduces the high-speed transmission communication packet 93 from the received baseband signal and transfers it to the master station control device 22.

  As described above, according to the train radio communication system of FIG. 10, in the bidirectional communication between the master station 21 and the slave station 23, the Doppler shift of the transmission wave F1 from the Doppler shift amount ΔFrd of the transmission / reception wave of the radar device 1001 The minute ΔF1 is sequentially calculated, and the master station radio transmitting / receiving apparatus 1002 periodically and alternately transmits the low-speed transmission communication packet by AM modulation and the high-speed transmission communication packet by multi-level modulation including the information of the Doppler shift amount ΔF1. As a result, the slave station radio transmitting / receiving apparatus 1003 can easily correct the Doppler shifts ΔF1 and ΔF2 in real time, thereby ensuring stable communication quality.

  In the master station radio transceiver apparatus 1002, most of the circuits that calculate the Doppler shift ΔF1 and generate the low-speed transmission communication packet 92 and the high-speed transmission communication packet 93 can be realized by digital signal processing. 1002 can be realized by adding an AM modulation circuit having an easy and inexpensive configuration to a general wireless transmission / reception apparatus using multi-level modulation.

  Also in the slave station wireless transmission / reception device 1003, most of the circuits that extract the Doppler shift information and generate the frequency control signal can be realized by digital signal processing. The slave station wireless transmission / reception device 1003 uses general multi-level modulation. This can be realized by adding an envelope detection circuit having an easy and inexpensive configuration to the wireless transceiver.

  By the way, the master station radio transmitter 32 in FIG. 3, the master station radio receiver 42 in FIG. 4, the master station radio transmitter 82 in FIG. 8, the slave station radio receiver 83, and the master station radio transceiver 1002 in FIG. In the slave station radio transmission / reception device 1003, frequency conversion is performed using both high frequency band and intermediate frequency band oscillators. However, even when only one of the oscillators is used, the same Doppler shift correction can be performed. is there.

(Supplementary note 1) A wireless communication device that transmits data to a mobile wireless communication device installed in a mobile body,
Measuring means for transmitting a radar wave, receiving a radar wave reflected by the moving body, and measuring a Doppler shift frequency;
Control means for outputting a control signal for correcting the Doppler shift based on the measured frequency;
A variable frequency oscillation means for outputting a local signal having a frequency according to the control signal;
Modulation means for generating a modulated wave from a baseband signal of transmission data;
A wireless communication apparatus comprising: a transmission unit configured to perform frequency conversion of the modulated wave using the local signal and to transmit a radio wave having a frequency corrected for the Doppler shift to the mobile wireless communication apparatus.
(Appendix 2) A wireless communication device that receives data from a mobile wireless communication device installed in a mobile body,
Measuring means for transmitting a radar wave, receiving a radar wave reflected by the moving body, and measuring a Doppler shift frequency;
Control means for outputting a control signal for correcting the Doppler shift based on the measured frequency;
A variable frequency oscillation means for outputting a local signal having a frequency according to the control signal;
Receiving means for receiving radio waves from the mobile radio communication device, performing frequency conversion of a received wave using the local signal, and extracting a modulation component of the received wave with the Doppler shift corrected;
A radio communication apparatus comprising: demodulation means for generating a baseband signal of received data from a modulation component of the received wave.
(Supplementary Note 3) A wireless communication device that transmits and receives data to and from a mobile wireless communication device installed in a mobile body by a passive method using a frequency-modulated continuous wave,
Measuring means for transmitting a radar wave, receiving a radar wave reflected by the moving object, and measuring a Doppler shift frequency and a time from when the radar wave is transmitted until the reflected radar wave is received;
Control means for outputting a control signal indicating a frequency modulation continuous wave curve for correcting the Doppler shift based on the measured frequency and time;
A variable frequency oscillation means for outputting a local signal having a frequency that changes in accordance with the control signal;
Modulation means for generating a modulated wave from a baseband signal of transmission data;
Transmitting means for performing frequency conversion of the modulated wave using the local signal and transmitting a radio wave having a frequency corrected for the Doppler shift to the mobile radio communication device;
Receiving means for receiving radio waves transmitted from the mobile radio communication device in a passive manner, performing frequency conversion of received waves using the local signals, and extracting modulated components of received waves with corrected Doppler shift;
A radio communication apparatus comprising: demodulation means for generating a baseband signal of received data from a modulation component of the received wave.
(Additional remark 4) It further has a storage means to store the data of a plurality of frequency modulation continuous wave curves calculated in advance, and the control means stores the data of the frequency modulation continuous wave curve corresponding to the measured frequency and time. The wireless communication apparatus according to appendix 3, wherein the control signal is generated by reading from a storage unit.
(Additional remark 5) It is a radio | wireless communication apparatus which transmits data with respect to the mobile radio | wireless communication apparatus installed in the mobile body, Comprising:
Measuring means for transmitting a radar wave, receiving a radar wave reflected by the moving body, and measuring a Doppler shift frequency;
A generation means for generating a low-speed transmission communication packet including information of the measured frequency, and a high-speed transmission communication packet including transmission data;
An oscillation means for transmission for outputting a local signal for transmission;
Modulation means for generating a modulated wave by performing amplitude modulation on the low-speed transmission communication packet at a frequency lower than a carrier wave, and performing multi-level modulation on the high-speed transmission communication packet;
A radio communication apparatus comprising: a transmission unit that performs frequency conversion of the generated modulated wave using the local signal for transmission and transmits radio waves of the converted frequency to the mobile radio communication apparatus. .
(Supplementary Note 6) A reception oscillation unit that outputs a reception local signal, and a radio wave having a frequency in which a Doppler shift is corrected based on frequency information included in the low-speed transmission communication packet is received from the mobile radio communication device. Receiving means for performing frequency conversion of a received wave using the reception local signal and extracting a modulation component of the received wave; and demodulating means for generating a baseband signal of received data from the modulation component of the received wave The wireless communication device according to appendix 5, wherein the wireless communication device is provided.
(Supplementary note 7) A mobile wireless communication device installed in a mobile body and receiving data from another wireless communication device,
Multi-level modulation is performed on a radio wave generated by performing amplitude modulation at a frequency lower than a carrier wave on a low-speed transmission communication packet including information on the Doppler shift frequency of the mobile body and a high-speed transmission communication packet including transmission data. Receiving means for receiving the radio wave generated by the other wireless communication device;
Demodulating means for generating a baseband signal of the low-speed transmission communication packet from the received wave of the low-speed transmission communication packet by envelope detection and generating a baseband signal of the high-speed transmission communication packet from the modulation component of the reception wave of the high-speed transmission communication packet When,
Control means for extracting information on the Doppler shift frequency from a baseband signal of the low-speed transmission communication packet, and outputting a control signal for reception for correcting the Doppler shift based on the extracted frequency;
A variable frequency oscillation means for reception that outputs a local signal for reception according to the control signal for reception;
Receiving conversion means for performing frequency conversion of a received wave of the high-speed transmission communication packet using the receiving local signal, extracting a modulation component of the received wave with the Doppler shift corrected, and outputting the extracted component to the demodulating means; A mobile radio communication apparatus comprising:
(Supplementary note 8) Transmission frequency variable oscillation means for outputting a transmission local signal having a frequency corresponding to the transmission control signal, modulation means for generating a modulated wave from a baseband signal of transmission data, and the transmission local signal Further comprising: a transmitting means for performing frequency conversion of the modulated wave using, and transmitting a radio wave of the converted frequency to the other wireless communication device, and the control means is based on the extracted frequency, The mobile radio communication apparatus according to appendix 7, wherein a transmission control signal for correcting a Doppler shift is output to the transmission frequency variable oscillation means.

1 is a principle diagram of a mobile radio communication system of the present invention. It is a conceptual diagram of a train radio communication system. It is a lineblock diagram of the 1st train radio communications system. It is a block diagram of a 2nd train radio | wireless communications system. It is a block diagram of a 3rd train radio | wireless communications system. It is a figure which shows the change of a frequency. It is a figure which shows the data structure of an FM-CW curve. It is a block diagram of a 4th train radio | wireless communications system. It is a figure which shows a communication packet. It is a block diagram of a 5th train radio | wireless communications system. It is a figure (the 1) which shows an automatic train stop system. It is a figure (the 2) which shows an automatic train stop system.

Explanation of symbols

11 Rail 12, 25 Train 13 Stop signal 14, 18 Information transmission device 15 Cable 16 Ground child 17 Upper child 19 Driver's cab device 21 Master station 22 Master station controller 23 Slave station 24 Slave station controller 31, 41, 51, 61, 81, 1001 Radar device 32, 82 Master station radio transmitter 33, 83 Slave station radio receiver 42 Master station radio receiver 43 Slave station radio transmitter 52, 1002 Master station radio transmitter / receiver 53, 1003 Slave station radio transmitter / receiver Device 91 Timing structure of communication packet 92 Low-speed transmission communication packet 93 High-speed transmission communication packet 101 Measuring unit 102 Control unit 103 Frequency variable oscillation unit 104 Modulating unit 105 Transmitting unit 106 Receiving unit 107 Demodulating unit 111 Mobile body 112 Mobile wireless communication device 301, 401, 501, 801, 1011 Antenna 302, 402, 802, 1012 Doppler frequency measurement circuit 303, 412, 503, 520, 803, 1013, 1036 transmitting antenna 304, 413, 504, 519, 804, 1014, 1037 high frequency band transmission amplifier circuit 305, 805, 1015, 1038 Transmitter high frequency band frequency converter 306, 1039 Transmitter high frequency band VCO
307, 807, 1017, 1040 Transmitter intermediate frequency band frequency converter 308, 1041 Transmitter intermediate frequency band VCO
309, 409, 510, 818, 1042 Frequency control circuit 310, 416, 512, 522, 810, 1020, 1043 Modulation circuit 311, 317, 411, 417, 514, 523, 811, 820, 1028, 1044 Baseband processing circuit 312, 403, 509, 515, 812, 1021, 1029 Reception antenna 313, 404, 508, 516, 813, 1022, 1030 High frequency band reception amplification circuit 314, 414 Frequency converter 315 Receiving oscillator 316, 410, 513, 521 , 819, 1027, 1035 Demodulator circuit 405, 507, 814, 1023, 1031 Receiver high frequency band frequency converter 406, 815, 1032 Receiver high frequency band VCO
407, 816, 1025, 1033 Receiver intermediate frequency band frequency converter 408, 817, 1034 Receiver intermediate frequency band VCO
415 Transmitter oscillator 502 Doppler frequency / relative distance measurement circuit 506 Transmission / reception high frequency band VCO
511 Memory 517 Signal distributor 531 Broken line 532 Solid line 533 One-dot chain line 806, 1016 Transmitter high frequency band oscillator 808, 1018 Transmitter intermediate frequency band oscillator 809, 1019 Data packet generation circuit 901, 904 Sync data 902, 905 Control data 903, 907 Error detection code 906 Information data 1024 Receiver high frequency band oscillator 1026 Receiver intermediate frequency band oscillator F1, F2, F3 Frequency L Relative distance V Relative speed

Claims (3)

A wireless communication device that transmits and receives data by a passive method using a frequency-modulated continuous wave with a mobile wireless communication device installed in a mobile body,
Measuring means for transmitting a radar wave, receiving a radar wave reflected by the moving object, and measuring a Doppler shift frequency and a time from when the radar wave is transmitted until the reflected radar wave is received;
Control means for outputting a control signal indicating a frequency modulation continuous wave curve for correcting the Doppler shift based on the measured frequency and time;
A variable frequency oscillation means for outputting a local signal having a frequency that changes in accordance with the control signal;
Modulation means for generating a modulated wave from a baseband signal of transmission data;
Transmitting means for performing frequency conversion of the modulated wave using the local signal and transmitting a radio wave having a frequency corrected for the Doppler shift to the mobile radio communication device;
Receiving means for receiving radio waves transmitted from the mobile radio communication device in a passive manner, performing frequency conversion of received waves using the local signals, and extracting modulated components of received waves with corrected Doppler shift;
A radio communication apparatus comprising: demodulation means for generating a baseband signal of received data from a modulation component of the received wave. A wireless communication device that transmits data to a mobile wireless communication device installed in a mobile body,
Measuring means for transmitting a radar wave, receiving a radar wave reflected by the moving body, and measuring a Doppler shift frequency;
A generation means for generating a low-speed transmission communication packet including information of the measured frequency, and a high-speed transmission communication packet including transmission data;
An oscillation means for transmission for outputting a local signal for transmission;
Modulation means for generating a modulated wave by performing amplitude modulation on the low-speed transmission communication packet at a frequency lower than a carrier wave, and performing multi-level modulation on the high-speed transmission communication packet;
A radio communication apparatus comprising: a transmission unit that performs frequency conversion of the generated modulated wave using the local signal for transmission and transmits radio waves of the converted frequency to the mobile radio communication apparatus. . A mobile radio communication device installed in a mobile body and receiving data from another radio communication device,
Multi-level modulation is performed on a radio wave generated by performing amplitude modulation at a frequency lower than a carrier wave on a low-speed transmission communication packet including information on the Doppler shift frequency of the mobile body and a high-speed transmission communication packet including transmission data. Receiving means for receiving the radio wave generated by the other wireless communication device;
Demodulating means for generating a baseband signal of the low-speed transmission communication packet from the received wave of the low-speed transmission communication packet by envelope detection and generating a baseband signal of the high-speed transmission communication packet from the modulation component of the reception wave of the high-speed transmission communication packet When,
Control means for extracting information on the Doppler shift frequency from a baseband signal of the low-speed transmission communication packet, and outputting a control signal for reception for correcting the Doppler shift based on the extracted frequency;
A variable frequency oscillation means for reception that outputs a local signal for reception according to the control signal for reception;
Receiving conversion means for performing frequency conversion of a received wave of the high-speed transmission communication packet using the receiving local signal, extracting a modulation component of the received wave with the Doppler shift corrected, and outputting the extracted component to the demodulating means; A mobile radio communication apparatus comprising: