JP4056909B2 - Transmission capability monitoring device, reception capability monitoring device, and wireless communication system including these - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transmission capability monitoring device that monitors whether or not the transmission power of a wireless terminal has increased. The present invention also relates to a reception capability monitoring device that monitors whether or not reception sensitivity of a wireless terminal has increased. Furthermore, the present invention relates to a radio communication system including these transmission capability monitoring devices and reception capability monitoring devices.
[0002]
[Prior art]
In a wireless communication system, as a communication system that narrows a communication area so as to communicate only with a predetermined partner, for example, there is a wireless communication system between an on-board device and a ground device using a microwave transponder in rail traffic (for example, a patent) Reference 1).
[0003]
In this communication system, as shown in FIG. 12, for example, an interrogator (hereinafter referred to as a vehicle upper element) 2 is mounted on a vehicle 1, and a responder (hereinafter referred to as a ground element) is provided between rails 3 laid on the ground. 4 is installed. The vehicle 1 travels on the rail 3 while constantly transmitting the interrogation wave from the vehicle upper element 2, and when the ground element 4 receives the interrogation wave when the vehicle 1 passes over the ground element 4, the ground element 4 Data is transmitted between the vehicle child and the ground child by returning a response wave corresponding to the received interrogation wave. And the transmission area of the vehicle upper element 2 and the reception area of the ground element 4 are set to be narrow, the vehicle element 2 communicates only with the ground element 4 installed on the rail 3 side, and is installed on the adjacent rail 5 side. In order not to communicate with the ground element 6, the ground element 4 communicates only with the vehicle upper element 2 of the vehicle 1, and does not communicate with the vehicle element (not shown) of the vehicle traveling on the adjacent rail 5 side. Yes.
[0004]
[Patent Document 1]
JP 2000-269877 A
[0005]
[Problems to be solved by the invention]
However, when the transmission power of the vehicle upper 2 is increased due to the failure and the transmission area is expanded more than necessary, or when the reception sensitivity of the ground child 4 is increased due to the failure and the reception area is expanded more than necessary, There is a possibility of communication with the ground element 5 on the adjacent rail 5 side or the vehicle element of the traveling vehicle. When the operating frequency band is low (several hundred kHz band) as in the conventional magnetic coupling method used in, for example, an ATS system, a circuit configuration that reduces transmission power and reception sensitivity at the time of failure is Although easy, there is a drawback that the data transmission speed is slow. Due to the necessity of transmitting and receiving a large amount of information between the vehicle and the ground, it is desired to increase the data transmission speed, and a radio communication system with a high frequency band (GHz band) such as the above-described transponder method is desired. ing. However, with the transponder method, it is difficult to have a circuit configuration that reduces the transmission power and reception sensitivity at the time of failure. To cope with the expansion of the communication area at the time of failure, a monitor that monitors increases in transmission power and reception sensitivity. A circuit is needed.
[0006]
The present invention has been made paying attention to the above problems, and provides a novel transmission capability monitoring device capable of monitoring an increase in transmission power of a wireless terminal. Also provided is a reception capability monitoring device capable of monitoring an increase in reception sensitivity of a wireless terminal. Furthermore, it aims at providing a radio | wireless communications system provided with these transmission capability monitoring apparatuses and reception capability monitoring apparatuses.
[0007]
[Means for Solving the Problems]
  For this reason, the invention of claim 1 is a transmission capability monitoring device for monitoring the transmission power level of a wireless terminal, wherein a transmission signal output to the transmission antenna of the wireless terminal is input and the input signal is periodically attenuated. A power level detection output generation unit that generates a power level detection output by comparing a power level between the time of attenuation and the time of non-attenuation with a preset threshold, and a check according to the output state of the power level detection output A check data generation unit for generating data, and when the check data of the check data generation unit is predetermined predetermined data indicating that the power level detection output is an alternating output, the power level is determined to be normal, and the check A level determination unit that determines that the power level is abnormal when the data is different from the predetermined data and stops the transmission function of the wireless terminal when the abnormality is determined.The power level detection output generation unit is connected to the transmission path of the transmission signal and is periodically connected to the first changeover switch, and one end side of each of the first changeover switches is connected to the first changeover switch periodically in parallel with each other. A first signal path without an attenuator and a second signal path in which an attenuator is interposed, and each of the first signal path and the second signal path is controlled periodically in synchronization with the first changeover switch. A second changeover switch that is periodically switched to the end side, and a power level at which a signal input via the second changeover switch is converted into a direct current and then subjected to a level test with the threshold value to generate the power level detection output A detection unit, and when the signal is input via the second signal path, the power level detection unit temporarily increases the signal level so as to be equal to or higher than the threshold value. And configured to include a confirmation means for signal paths to check normal or not.
[0008]
  In such a configuration, the power level detection output generation unit receives the transmission signal and periodically attenuates the power level detection output by comparing with a threshold value set in advance to a power level between when the signal is attenuated and when it is not attenuated. Generate. If the power level is normal, the power detection output becomes an alternating signal, and if the power level increases more than necessary, the power detection output does not become an alternating signal. The check data generation unit generates check data of predetermined data when the output state of the power level detection output is an alternating signal, but generates check data different from the predetermined data when it is not an alternating signal. The level determination unit determines whether the check data generated by the check data generation unit is predetermined data. If the check data is predetermined data, the level determination unit determines that the transmission power is normal. On the other hand, when the check data is not predetermined data, it is determined that the transmission power is abnormal and the transmission function of the wireless terminal is stopped.The power level detection output generation unit periodically switches the first and second changeover switches in synchronization with each other. Thus, the transmission signal is not attenuated when passing through the first signal path side, but is attenuated by the attenuator when passing through the second signal path side, and is input to the power level detection unit. The power level detection unit determines the threshold value of the input signal and generates a power level detection output. At this time, if the attenuated signal is normally input, the signal level temporarily exceeds the threshold by the confirmation means. However, if the signal is not input, a signal exceeding the threshold is not generated. The disconnection failure of the two signal path can be understood.
[0013]
  Claim2As described above, the check data generation unit samples the power level detection output at predetermined time intervals, generates serial data based on the sampling data and previously stored reference data, and converts the serial data into the check data. It may be configured to output as
[0014]
  Claim3As described above, when both the power level detection output generation unit and the check data generation unit have a dual configuration, the power level detection output generation unit generates first and second power level detection outputs that are dually related to each other. A second power level detection output generation unit, wherein the check data generation unit converts a power level detection output of the first power level detection output generation unit into first check data; A second check data conversion unit for converting the power level detection output of the second power level detection output generation unit into second check data different from the first check data, and the first and second check data are alternately switched and output. The output switching unit is preferably configured to be provided.
[0015]
  Claim4As described above, if the level determination unit is provided separately from the wireless terminal, the wireless terminal does not increase in size.
  Claim5The present invention is a reception capability monitoring device for monitoring the reception sensitivity of a wireless terminal, wherein the demodulated signal level of a demodulation circuit that demodulates the reception signal of the wireless terminal is detected, and the signal level is increased by a predetermined level or more. A monitor unit that determines that reception sensitivity is abnormal when detected and stops the reception function of the wireless terminal;The monitor unit receives received data based on a received signal input from a receiving antenna to the demodulator circuit, and then periodically attenuates a test signal and supplies the test signal to the demodulator circuit; and A power level detection output generator for inputting a test signal demodulated by the demodulation circuit and generating a power level detection output by comparing the input signal with a threshold value set in advance to a power level between when the signal is attenuated and when the signal is not attenuated; A check data generation unit that generates check data according to an output state of the power level detection output, and a check data of the check data generation unit is a predetermined value that indicates that the power level detection output is an alternating output If the data is data, it is determined that the reception sensitivity is normal, and the reception data is validated. A level determination unit that invalidates reception data and stops the reception function of the wireless terminal, and the test signal supply unit is connected to the test signal generation unit that generates a test signal and the test signal generation unit. A first changeover switch that is periodically controlled to be switched, a first signal path without an attenuator that is connected in parallel to each other and whose one end side is periodically connected to the first changeover switch, and a second that is provided with an attenuator. A signal path, a second changeover switch that is periodically controlled in synchronization with the first changeover switch, and that is periodically connected to the other end of each of the first and second signal paths; A third changeover switch for switching and connecting the input side to the receiving antenna and the second changeover switch, and the power detection output generation unit receives a signal via the second signal path. When and was configured to include a confirmation means for the second signal path to increase control so that the signal level over temporarily the threshold value to confirm whether normal or not.
[0016]
  In such a configuration, the monitor unit detects the level of the demodulated signal of the demodulator circuit, determines that the detected signal level is higher than a predetermined level, determines that the reception sensitivity is abnormal, and stops the reception function of the wireless terminal. To do.Specifically, when reception data is acquired based on a reception signal input from the reception antenna to the demodulation circuit, the test signal generation unit of the test signal supply unit generates a test signal, and the first changeover switch and the second changeover switch Synchronize the switches and switch periodically. The test signal is not attenuated when passing through the first signal path side, but is attenuated by the attenuator when passing through the second signal path side, and is input from the third changeover switch to the power detection output generation unit via the demodulation circuit. . The power level detection output generation unit inputs the demodulated test signal that is periodically attenuated, and generates a power level detection output by comparing with a threshold set in advance to a power level between when the signal is attenuated and when it is not attenuated. If the power level is normal, the power detection output becomes an alternating signal, and if the power level increases more than necessary, the power detection output does not become an alternating signal. At this time, if the attenuated signal is normally input, the signal level temporarily exceeds the threshold value by the confirmation unit. However, if the signal is not input, a signal exceeding the threshold value is not generated. It can be seen that the signal path is broken. The check data generation unit generates check data of predetermined data when the output state of the power level detection output is an alternating signal, but generates check data different from the predetermined data when it is not an alternating signal. The level determination unit determines whether the check data generated by the check data generation unit is predetermined data. If the check data is predetermined data, the level determination unit determines that the reception sensitivity is normal and validates the reception data. On the other hand, when the check data is not predetermined data, it is determined that the reception sensitivity is abnormal, the reception data is invalidated, and the reception function of the wireless terminal is stopped.
[0022]
  Claim6As described above, a normally open switch that is turned on when the power detection output of the power level detection output generation unit is equal to or higher than a predetermined level is provided in the signal path for inputting the demodulation test signal of the demodulation circuit to the check data generation unit. On the other hand, the test signal including the test data generated by the check data generation unit is supplied from the test signal supply unit to the demodulation circuit, and the check data generation unit switches the switch check data according to the input demodulated test signal. And the level determination unit may determine that the normally open switch is normal when the switch check data is predetermined data.
[0023]
In such a configuration, when the normally open switch is turned on when the demodulated test signal of the demodulating circuit is equal to or higher than a predetermined level, the test data is input to the check data generating unit to generate predetermined switch check data. On the other hand, when the test data is input to the check data generation unit when the demodulated test signal is not higher than the predetermined level, the check data generation unit generates switch check data different from the predetermined data. The level determination unit determines whether the check data generated by the check data generation unit is predetermined data. If the check data is predetermined data, the level determination unit determines that the normally open switch is normal. On the other hand, when the check data is not predetermined data, the normally open switch is determined to be abnormal.
[0026]
  Claim7As described above, the check data generation unit samples the power level detection output at predetermined time intervals, generates serial data based on the sampling data and previously stored reference data, and converts the serial data into the check data. It may be configured to output as
[0027]
  Claim8As described above, when both the power level detection output generation unit and the check data generation unit have a dual configuration, the power level detection output generation unit generates first and second power level detection outputs that are dually related to each other. A second power level detection output generation unit, wherein the check data generation unit converts a power level detection output of the first power level detection output generation unit into first check data; A second check data conversion unit for converting the power level detection output of the second power level detection output generation unit into second check data different from the first check data, and the first and second check data are alternately switched and output. The output switching unit is preferably configured to be provided.
[0028]
  Claim9As described above, if the level determination unit is provided separately from the wireless terminal, the wireless terminal does not increase in size.
  Claim10The wireless communication system of the invention ofClaims 1-4A transmission capability monitoring device according to any one ofClaims 5-9A data communication is performed between a radio station including at least one monitor device of the reception capability monitor device according to any one of the above and a radio station including at least the other monitor device.
[0029]
In such a configuration, when data communication is performed between wireless stations, the transmission capacity monitoring apparatus and the reception capacity monitoring apparatus can monitor that the communication area is expanded more than necessary. As a result, it is possible to prevent communication with a wireless station other than a predetermined partner.
[0030]
  Claim11As described above, any one of the wireless stations may be a mobile station and the other may be a fixed station. In this case, the claim12As described above, if the mobile station wireless terminal is a vehicle top mounted on a railway vehicle, and the fixed station wireless terminal is a ground element disposed between rails of the railway vehicle, the railway traffic system Can be applied to.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
  Hereinafter, embodiments of the present invention will be described with reference to the drawings.
  FIG. 1 shows a transmission capability monitoring apparatus according to the present invention.Reference exampleIt is a block diagram which shows the structure of the radio station provided with.
[0032]
  In FIG.Reference exampleThe wireless station includes a wireless terminal 11 and a determination unit 12 as a level determination unit that determines the transmission power of the wireless terminal 11.
  The wireless terminal 11 includes a transmission circuit 21 that outputs a transmission signal including transmission data generated by a data generation unit (not shown), a transmission antenna 22 for transmitting the transmission signal to the outside, and a power level detection output generation unit. Power detection unit 23, a data processing unit 24 as a check data generation unit, and a serial communication unit 25 that serially transmits check data generated by the data processing unit 24.
[0033]
  The power detection unit 23 includes a transmission circuit21From transmit antenna22The transmission signal to be output is input, and the input signal is periodically attenuated to generate a power level detection output by comparing with a preset threshold value at a power level between when the signal is attenuated and when it is not attenuated. Yes, the first and second changeover switches 23A and 23B, the attenuator 23C, the first signal path 23a without the attenuator, the second signal path 23b with the attenuator 23C interposed, and the power level detector 23D Is provided.
[0034]
The first and second changeover switches 23A and 23B are periodically switched in synchronization with each other by a control signal from a control unit (not shown), and are periodically switched between the first signal path 23a and the second signal path 23b. Connect and periodically switch the path of the input signal. As a result, an AC signal is input to the power level detection unit 23D.
[0035]
As shown in FIG. 2, the power level detection unit 23 </ b> D includes a voltage effective value-DC conversion amplification unit 31, an operational amplification unit 32, and a threshold determination unit 33 as a level verification unit, and is configured to perform second switching. The AC signal input from the switch 23B is converted into a DC signal by the voltage effective value-DC converting amplifier 31 and the operational amplifier 32, and then this DC signal is compared with a threshold set in advance by the threshold determining unit 33 to determine a threshold value. A power level detection output is generated from the unit 33 and output. Here, the voltage effective value-DC conversion amplifier 31 and the operational amplifier 32 constitute an AC-DC converter.
[0036]
The data processing unit 24 generates check data corresponding to the output state of the power level detection output output from the power level detection unit 23D. Specifically, the power level detection output is sampled at predetermined time intervals, serial data is generated by performing exclusive OR operation on the sampling data and pre-stored reference data, and the serial data is output as check data It is.
[0037]
The serial communication unit 25 serially transmits the check data from the data processing unit 24 to the determination unit 12.
The determination unit 12 determines that the power level is normal when the check data serially transmitted from the wireless terminal 11 is predetermined predetermined data indicating that the power level detection output is an alternating output, and the check data is the predetermined data. Is determined as an abnormal power level, and when the abnormality is determined, the transmission function of the wireless terminal 11 is stopped. The serial communication unit 41, the data collating unit 42 having a dual system configuration, and the power supply as a power supply cutoff unit An interruption relay 43 and a terminal power supply 44 are provided.
[0038]
The serial communication unit 41 receives check data serially transmitted from the wireless terminal 11.
The data collating unit 42 collates check data input from the serial communication unit 41 with predetermined collated data stored in advance, the two collating units of the main collating unit and the subordinate collating unit. The main collation unit and the subordinate collation unit execute the same collation operation, and when both are normal, the collation result of the main collation unit is adopted. If the check data matches the predetermined data as a result of the collation, it is determined that the power is normal, and the power cutoff relay 43 is held in the ON state. On the other hand, if the check data does not match the predetermined data, it is determined that the power is abnormal, the power cutoff relay 43 is turned off, and the power supply path between the terminal power supply 44 and the wireless terminal 11 is shut off. Here, the power detection unit 23, the data processing unit 24, the serial communication unit 25, and the determination unit 12 constitute a transmission capability monitoring device.
[0039]
Next, the operation will be described.
Transmission power output from the transmission circuit 21 to the transmission antenna 22 is input to the power detection unit 23. In the power detector 23, the first and second changeover switches 23A and 23B are controlled to be switched in synchronization. When the first and second changeover switches 23A and 23B are connected to the first signal path 23a, the input signal is input to the power level detection unit 23D without being attenuated, and the first and second changeover switches 23A and 23B When connected to the second signal path 23b, the input signal is attenuated by the attenuator 23C and input to the power level detector 23D. Thus, an AC input signal as shown in FIG. 3 is input to the power level detection unit 23D. The AC signal input to the power level detector 23D is converted into a DC signal by the voltage effective value-DC converting amplifier 31 and the operational amplifier 32, and a rectangular signal as shown in FIG. And input to the threshold value determination unit 33. The threshold determination unit 33 generates an output when the input signal level is equal to or higher than the threshold. Therefore, if the transmission power is normal, the power threshold determination unit 33 generates the power level detection output of the alternating signal as shown in FIG. 3 in synchronization with the switching cycle of the first and second changeover switches 23A and 23B. The data processing unit 24 samples the power level detection output input from the power detection unit 23 at a predetermined time interval, generates the sampling data of FIG. 4, and performs an exclusive OR operation on the sampling data and the previously stored reference data. Then, check data is generated as shown in FIG. This check data is serially transmitted from the serial communication unit 25 to the determination unit 12.
[0040]
The determination unit 12 collates the check data transmitted via the serial communication unit 41 with predetermined collation data stored in advance by the dual system collation unit 42. If the output state of the power level detection output of the power detection unit 23 is an alternating signal as shown in FIG. 3, the check data matches the verification data, the verification unit 42 determines that the transmission power is normal, and turns on the power shut-off relay. The power supply to the wireless terminal 11 is continued while maintaining the state. On the other hand, for example, when the transmission power increases more than necessary, the level of the input signal during the attenuation period of FIG. 3 increases and the output level of the operational amplifier 32 exceeds the threshold value, the power level detection output does not become an alternating signal. It becomes a DC signal. In this case, the check data is different from the verification data, the verification result of the verification unit 42 is inconsistent and the verification unit 42 determines that the transmission power is abnormal, turns off the power shut-off relay, and supplies power to the wireless terminal 11. The road is blocked and the transmission function of the wireless terminal 11 is stopped.
[0041]
Also, when the transmission power is reduced more than necessary, the input signal level in the non-attenuated period of FIG. 3 is reduced, and the output level of the operational amplifier 32 becomes less than the threshold value, check data different from the verification data is generated. Therefore, the power cutoff relay is turned OFF, the power supply path to the wireless terminal 11 is interrupted, and the transmission function of the wireless terminal 11 is stopped.
[0042]
  Also,Reference exampleThen, as shown in FIG. 4, the power level detection output is sampled at a predetermined time interval shorter than the switching cycle of the first and second changeover switches 23A and 23B, and the exclusive OR operation of the sample data and the reference data is performed. The check data is generated by For this reason, for example, when the power level detection output level temporarily decreases as indicated by the dotted line in FIG. 4 due to a temporary failure, the check data indicated by the diagonal line in FIG. 4 is different from the normal data. The collation result of the collation unit 42 becomes inconsistent, and the transmission function of the wireless terminal 11 is stopped. Even when the power level detection output level temporarily increases, the transmission function of the wireless terminal 11 is similarly stopped, unlike when the check data is normal.
[0043]
  As aboveReference exampleAccording to the above, when the transmission power of the wireless terminal 11 increases more than necessary, the transmission function of the wireless terminal 11 can be stopped. In addition, the transmission function of the wireless terminal 11 can be stopped even for an intermittent failure in which the transmission capability temporarily becomes abnormal. In addition, since the determination unit 12 is provided separately from the wireless terminal 11, the wireless terminal 11 does not increase in size.
[0044]
  Next, the present inventionFirst embodimentWill be described.
  the aboveReference exampleWith this configuration, even if a disconnection occurs in the second signal path 23b, there is a possibility that the power level detection output of the alternating signal is generated from the power detection unit 23 as in the normal state.First embodimentSolves this problem.
[0045]
  In FIG.First embodimentThe power level detection unit is shown. Other configurations areReference exampleIt is the same.
  As shown in FIG.First embodimentThe power level detection unit 23D ′ includes a confirmation circuit as a confirmation unit for confirming whether the second signal path 23b is normal between the voltage effective value-DC conversion amplification unit 31 and the operational amplification unit 32. 34 is provided. The confirmation circuit 34 includes two resistors and one switch 34A. The switch 34A is ON / OFF controlled in synchronization with the first and second changeover switches 23A and 23B, and the first and second changeover switches 23A and 23B. Is turned off when connecting to the second signal path 23b side. The output of the operational amplifier 32 exceeds the threshold value of the threshold value determination unit 33 when the switch 34A is turned off.
[0046]
Next, the operation will be described with reference to FIG.
When the first and second changeover switches 23A and 23B are connected to the second signal path 23b side and the switch 34A is turned OFF during the period when the attenuated signal is input to the power level detection unit 23D ′, the second signal path 23b is If the attenuation signal is normal and input, the switch 34A is turned OFF as shown in FIG. 6, and the output of the operational amplifier 32 exceeds the OFF period threshold, and the power level detection output is as shown in FIG. When the power level detection output is in the state shown in FIG. 6, the data processing unit 24 generates predetermined check data that is the same as the verification data. On the other hand, if the second signal path 23b is disconnected, no signal is input during the attenuation period, and the output of the operational amplifier 32 does not change even if the switch 34A is turned OFF. The power level detection output does not become as shown in FIG. Thereby, the determination part 12 performs abnormality determination.
[0047]
  Therefore,First embodimentAccordingly, when a disconnection failure occurs in the second signal path 23b, the determination unit 12 makes an abnormality determination, and the transmission function of the wireless terminal 11 can be stopped.
[0048]
  next,Second embodimentWill be described.
  FIG. 7 shows a transmission capability monitoring apparatus according to the present invention.Second embodimentThe structure of the radio station provided with In addition, the same code | symbol is attached | subjected to the same element as 1st Embodiment, and description is abbreviate | omitted.
[0049]
In FIG. 7, the radio station of this embodiment differs from the first embodiment in the configuration of the radio terminal 11 and has a power detection unit and a data processing unit in a dual system configuration. The wireless terminal 11 of the present embodiment includes two first and second power detection units 23X and 23Y configured similarly to the first embodiment. As shown in FIG. 8, the data processing unit 24 ′ includes a first check data conversion unit 24A that converts the power level detection output of the first power detection unit 23X into first check data X, and a second power detection unit 23Y. A second check data conversion unit 24B that converts the power level detection output into second check data Y different from the first check data X, and first and second of the first check data conversion unit 24A and the second check data conversion unit 24B. A changeover switch 24C is provided as an output changeover unit that alternately outputs the check data X and Y. The first power detection unit 23X and the second power detection unit 23Y are configured to control the switching of the first and second changeover switches 23A and 23B so that the power level detection outputs having a dual relationship with each other are generated.
[0050]
Next, the operation will be described.
The operation until the power level detection output is generated from each of the first power detection unit 23X and the second power detection unit 23Y is the same as that of the first embodiment. The data processing unit 24 ′ generates the first check data in the first check data conversion unit 24A according to the power level detection output state of the first power detection unit 23X, and the power level detection output state of the second power detection unit 23Y. In response to this, the second check data conversion unit 24B generates the second check data. The first and second check data X and Y are serially transmitted from the serial communication unit 25 to the determination unit 12 alternately by the switching operation of the changeover switch 24C. In the determination unit 12, the collation unit 42 collates whether or not the first check data X and the second check data Y are predetermined data. If the first and second check data X and Y are predetermined data, it is determined that the transmission capability of the wireless terminal 11 is normal. If the first and second check data X and Y are different from the predetermined data, It is determined that the transmission capability of the wireless terminal 11 is abnormal, the power to the wireless terminal 11 is shut off, and the transmission function is stopped.
[0051]
  TakeSecond embodimentAccording to the above, the transmission capability of the wireless terminal 11 can be monitored as long as the first and second power detection units 23X and 23Y do not fail simultaneously. In the present embodiment, the power level detection outputs of the first and second power detection units 23X and 23Y are output in a dual relationship with each other. When a failure occurs in which the output of the power detection unit 23X is connected to the second check data conversion unit 24B, and the same power level detection output is input to both the check data conversion units 24A and 24B, the second check data Y is different. Anomalies can be detected.
[0053]
Next, the reception capability monitoring apparatus according to the present invention will be described.
FIG. 9 is a block diagram illustrating a configuration of a radio station including the first embodiment of the reception capability monitoring apparatus.
[0054]
In FIG. 9, the wireless station of this embodiment includes a wireless terminal 51 and a determination unit 52 as a level determination unit that determines the reception sensitivity of the wireless terminal 51.
The wireless terminal 51 includes a receiving antenna 61 that receives a signal transmitted from the outside, a demodulation circuit 62 that demodulates the received / received signal, a test signal generator 63, first and second changeover switches 64A and 64B, and attenuation. The second signal path 66b without the attenuator 65, the second signal path 66b with the attenuator 65 interposed, and the input side of the demodulation circuit 62 are switched and connected to the second changeover switch 64B and the receiving antenna 61. 3-switch 67, a power level detection unit 68 as a power level detection output generation unit, a data processing unit 69 as a check data generation unit, and a serial communication unit for serially transmitting check data generated by the data processing unit 68 70 and a normally open switch 71 for inputting the output signal of the demodulation circuit 62 to the data processing unit 69.
[0055]
The test signal generator 63 generates a test signal including test data generated by the data processor 69. The first and second changeover switches 64A and 64B are periodically switched in synchronization with each other by a control signal from a control unit (not shown), and are periodically switched and connected to the first signal path 66a and the second signal path 66b. To do. As a result, the test signal is periodically attenuated and supplied to the demodulation circuit 62 via the third changeover switch 67. Here, the test signal generator 63, the first and second changeover switches 64A and 64B, the attenuator 65, the first and second signal paths 66a and 66b, and the third changeover switch 67 constitute a test signal supply unit. Composed.
[0056]
  The power level detection unit 68 is a power level detection unit of the transmission capability monitoring device described above.23D 'Is the same configuration as (FIG.reference).
  The normally open switch 71 is turned on when the power level detection output of the power level detector 68 is high, and inputs the signal detected by the demodulation circuit 62 to the data processing circuit 69. The data processing unit 69 has the same configuration as the data processing circuit 24 of the transmission capability monitoring device described above, and generates check data corresponding to the output state of the power level detection output output from the power level detection unit 68. is there. Specifically, the power level detection output is sampled at a predetermined time interval, serial data is generated by performing exclusive OR operation with the sampling data and pre-stored test data as reference data, and this serial data is output as check data It is the structure to do. In addition, switch check data is generated from test data included in a test signal input via the normally open switch 71.
[0057]
The serial communication unit 70 serially transmits the received data, check data for power level check from the data processing unit 69 and switch check data to the determination unit 52.
[0058]
The determination unit 52 is similar to the determination unit 12 of the transmission capability monitor device described above, and the check data serially transmitted from the wireless terminal 51 is predetermined predetermined data indicating that the power level detection output is an alternating output. The power level is determined to be normal at a certain time, the power level is determined to be abnormal when the check data is different from the predetermined data, and the reception function of the wireless terminal 51 is stopped when the abnormality is determined. Data collating unit 82, a power cutoff relay 83 as a power supply cutoff unit, and a terminal power source 84. Since the serial communication unit 81, the data collation unit 82, the power cutoff relay 83, and the terminal power source 84 have the same configuration as in the case of the transmission capability monitoring device, description thereof will be omitted. Here, the test signal supply unit, the power level detection unit 68, the data processing unit 69, the serial communication unit 70, and the determination unit 52 constitute a reception capability monitoring unit.
[0059]
Next, the operation will be described.
The reception capability monitoring device of this embodiment is configured to check whether the reception sensitivity is normal or not by generating a test signal after receiving reception data.
[0060]
Normally, the third changeover switch 67 is connected to the receiving antenna 61 side. When the reception signal is received, it is demodulated by the demodulation circuit 62, and the demodulated signal is input to the power level detection unit 68. If the demodulated signal level is greater than the threshold value of the threshold value determination unit of the power level detection unit 68, the normally open switch 71 is turned on by the power level detection output from the power level detection unit 68 and the demodulated signal is input to the data processing unit 69. Demodulated as data and transmitted to the determination unit 52 by the serial communication unit 70.
[0061]
When the received data is demodulated by the data processing unit 69, the data processing unit 69 outputs test data for checking reception sensitivity to the test signal generating unit 63, and the test signal generating unit 63 outputs the input test data. Generate a test signal containing. At this time, the third changeover switch 67 is changed over to the second changeover switch 64B side. The test signal is periodically attenuated by the periodic switching operation of the first and second changeover switches 64A and 64B and is input to the demodulation circuit 62, and a demodulated test signal is generated. If the reception sensitivity is normal, a power level detection output of an alternating signal is generated from the power level detection unit 68, predetermined check data is generated by the data processing unit 69, and serially transmitted to the determination unit 52. The determination unit 52 collates the transmitted check data with predetermined collation data stored in advance by the dual system collation unit 82. If they match, it is determined that the reception sensitivity is normal, and the power shut-off relay 83 is kept in the ON state. Then, the power supply to the wireless terminal 51 is continued. Also, the received data is determined to be valid.
[0062]
On the other hand, for example, if the received power increases more than necessary and the level of the demodulated test signal exceeds the threshold value during the decay period, the power level detection output does not become an alternating signal and the check data becomes data different from the verification data. 82, the collation result is inconsistent, and the collation unit 82 determines that the reception sensitivity is abnormal, invalidates the received data, turns off the power shut-off relay 83, shuts off the power supply path to the wireless terminal 51, and The reception function of the terminal 51 is stopped. Even when the reception sensitivity is unnecessarily lowered, check data different from the verification data is generated, the power cutoff relay 83 is turned OFF, the power supply path to the wireless terminal 51 is shut off, and the reception of the wireless terminal 51 is performed. The function is stopped.
[0063]
If the normally open switch 71 is normal, part of the test data is input to the data processing unit 69 only when the power level detection output of the power level detecting unit 68 is high. If a failure occurs, even test data that is not input in the normal state is input to the data processing unit 69. In this case, since switch check data different from the switch check data based on the normal input test data is generated, a failure of the normally open switch 71 is detected by the collation operation of the determination unit 52.
[0064]
  As described above, according to the reception capability monitoring device of this embodiment, when the reception sensitivity of the wireless terminal 51 increases more than necessary, the reception function of the wireless terminal 51 can be stopped. Further, the reception function of the wireless terminal 51 can be stopped even for an intermittent failure in which the reception sensitivity temporarily becomes abnormal. Further, since the determination unit 52 is provided separately from the wireless terminal 51, the wireless terminal 51 is not increased in size. Also, a failure of the normally open switch 71 can be detected.Further, since the disconnection failure of the second signal path 66B can be detected, the reliability of the reception capability monitoring device can be improved.
[0065]
Next, a second embodiment will be described.
FIG. 10 shows a configuration of a radio station provided with the second embodiment of the reception capability monitoring apparatus of the present invention. In addition, the same code | symbol is attached | subjected to the same element as 1st Embodiment, and description is abbreviate | omitted.
[0066]
In FIG. 10, the radio station of the present embodiment is different from the first embodiment in the configuration of the radio terminal 51, and has a dual system configuration of a power level detection unit and a data processing unit. The wireless terminal 51 of this embodiment includes two first and second power level detectors 68X and 68Y configured in the same manner as in the first embodiment. The data processing unit 69 ′ converts the power level detection output of the first power level detection unit 68X into the first check data X and detects the power level of the second power level detection unit 68Y, as in the case of the transmission capability monitoring device. The output is converted into second check data Y different from the first check data X, and the first and second check data X and Y are alternately switched and output.
[0067]
  The operation of the transmission capability monitoring deviceSecond embodimentIt is the same as the case of. That is, the data processing unit 69 ′ generates the first check data X according to the power level detection output state of the first power level detection unit 68X, and according to the power level detection output state of the second power level detection unit 68Y. Second check data Y is generated. The first and second check data X and Y are serially transmitted to the determination unit 52 and checked whether or not each is predetermined data. If the first and second check data X and Y are predetermined data, it is determined that the reception sensitivity of the wireless terminal 51 is normal. If the first and second check data X and Y are different from the predetermined data, It is determined that the reception capability of the wireless terminal 51 is abnormal, the power to the wireless terminal 51 is shut off, and the reception function is stopped.
[0068]
If the power level detection outputs of the first power level detection unit 68X and the second power level detection unit 68Y are in a dual relationship with each other, the output of the first power level detection unit 68X in the data processing unit 69 ′ is the first. It is possible to detect a failure that is connected to the 2-check data converter.
[0070]
Next, a radio communication system according to the present invention for performing data communication between a radio station equipped with the above-described transmission capability monitor device and a radio station equipped with a reception capability monitor device will be described.
[0071]
FIG. 11 shows an embodiment of the wireless communication system of the present invention, and an example applied to data communication between on-vehicle and ground of rail traffic will be described.
In FIG. 11, the wireless communication system of the present embodiment is a vehicle-to-ground wireless communication system using a microwave transponder in rail traffic, and an onboard element 101 including an interrogator as a wireless terminal is provided on the vehicle 100 side. An on-board device 102 connected to the on-board element 101 is mounted. On the ground side, a ground element 104 comprising a responder as a wireless terminal and a repeater 105 connected to the ground element 104 are installed between a pair of rails 103 laid on the ground. The power of the ground unit 104 is supplied from the power supply device 106 via the repeater 105. The on-board element 101 and the on-board device 102 are mobile stations, and the on-ground element 104 and the repeater 105 are fixed stations.
[0072]
The on-board element 101 has the configuration of the wireless terminal 11 of the transmission capability monitoring apparatus described with reference to FIGS. 1 to 8, and the determination unit 12 is provided on the on-board apparatus 102. The ground unit 104 has the configuration of the wireless terminal 51 of the reception capability monitoring apparatus described with reference to FIGS. 9 and 10, and a determination unit 52 is provided in the repeater 105. The power supply device 106 corresponds to the terminal power supply of the determination unit 52 in the repeater 105.
[0073]
Next, the operation will be described.
The vehicle upper element 101 sets the directivity of the transmission antenna so that it communicates only with the ground element 104 installed on the side of the rail 103 on which the vehicle 100 travels and does not communicate with the adjacent ground element on the rail side. Is set appropriately. Similarly, the ground antenna 104 communicates only with the vehicle upper arm 101 mounted on the vehicle 100 traveling on the rail 103 and does not communicate with the vehicle upper arm of the vehicle traveling on the adjacent rail side. Is set narrow and the receiving sensitivity is appropriately set.
[0074]
When the vehicle 100 traveling on the rail 3 while constantly transmitting the interrogation wave from the vehicle upper element 101 passes the ground element 104, the ground element 104 receives the interrogation wave and receives the write data from the vehicle 100 side. . The ground unit 104 that has received the interrogation wave returns a response wave and transmits response data corresponding to the received write data to the vehicle 100 side. In this way, data transmission is performed between the vehicle and the ground. If the transmission power of the vehicle upper element 101 increases more than necessary, the transmission function of the vehicle upper element 101 is stopped by the determination unit of the transmission capacity monitoring device as described above. If the reception sensitivity of the ground unit 104 increases more than necessary, the reception function of the ground unit 104 is stopped by the determination unit of the reception capability monitor device as described above. When an increase in reception sensitivity of the ground unit 104 is detected, the power to the ground unit 104 is cut off, so the ground unit 104 does not transmit response data. Further, only when the ground element 104 receives write data of a predetermined power or more from the vehicle upper element 101, it is more effective to suppress the expansion of the communication area if the response data is set to be returned.
[0075]
Therefore, it is possible to prevent communication with a ground element or a vehicle element on the adjacent rail side, and erroneous data transmission can be prevented. By providing the determination unit in the on-board device 102 separately from the on-board element 101, the size of the on-board element 101 does not increase. Similarly, by providing the determination unit in the repeater 105 separately from the ground unit 104, the size of the ground unit 104 does not increase. In addition, since the repeater 105 can be installed near the power supply device 106 without restrictions on the installation location, the cable connected to the power supply device 106 can be shortened even when the power consumption in the determination unit of the duplex configuration is large. The power loss due to the cable can be reduced.
[0076]
In the above embodiment, an example has been described in which the transmitting side is a mobile station and the receiving side is a fixed station. However, in the wireless communication system of the present invention, the transmitting side may be a fixed station and the receiving side may be a mobile station. Both radio stations that transmit data may have both transmission and reception functions. Needless to say, the wireless communication system of the present invention can be applied not only to the railway traffic system but also to other systems such as a traffic control system for automobiles and a ticket gate processing system for automatic ticket gates.
[0077]
【The invention's effect】
  As described above, according to the present invention, when the transmission power increases more than necessary, the transmission function of the wireless terminal can be stopped, and when the reception sensitivity increases more than necessary, the reception function of the wireless terminal can be stopped. Therefore, in a narrowband communication system in which data communication is performed only with a predetermined partner, it is possible to prevent data communication with a partner other than the predetermined partner.Further, it can be confirmed whether or not the second signal path is normal.Therefore, the reliability of the narrowband communication system can be improved.
[Brief description of the drawings]
FIG. 1 shows a transmission capability monitoring apparatus according to the present invention.Reference exampleBlock diagram of a radio station comprising
FIG. 2 is a block configuration diagram of a power level detection unit.
FIG. 3 is an operation explanatory diagram of a power level detection unit.
FIG. 4 is an operation explanatory diagram of a data processing unit.
FIG. 5 shows a transmission capability monitor device.First embodimentBlock diagram of the power level detection unit showing
[Fig. 6]First embodimentOf operation of power level detector
FIG. 7 shows a transmission capability monitor device.Second embodimentBlock diagram of a radio station comprising
[Fig. 8]Second embodimentConfiguration diagram of the main data processing unit
FIG. 9 is a block diagram of a radio station including the first embodiment of the reception capability monitoring apparatus according to the present invention.
FIG. 10 is a block configuration diagram of a radio station including a second embodiment of a reception capability monitoring apparatus.
FIG. 11 is a schematic configuration diagram showing an embodiment of a wireless communication system according to the present invention.
FIG. 12 is an explanatory diagram of problems of a conventional wireless communication system
[Explanation of symbols]
11, 51 Wireless terminal
12,52 judgment part
21 Transmitting antenna
22 Transmitter circuit
23, 23X, 23Y Power detection unit
23C, 65 attenuator
23D, 68, 68X, 68Y Power level detector
24, 24 ', 69 Data processing section
34 Confirmation circuit
42,82 Double collation unit
43,83 Relay for power shutdown
61 Receiving antenna
62 Demodulation circuit
63 Test signal generator
71 Normally open switch
101 Car upper
102 Onboard equipment
104 ground child
105 repeater

Claims (12)

A transmission capability monitoring device for monitoring a transmission power level of a wireless terminal,
Input a transmission signal to be output to the transmission antenna of the wireless terminal, periodically attenuate the input signal, and compare the power level between the time of attenuation and the time of non-attenuation, and the power level detection output A power level detection output generation unit for generating
A check data generation unit that generates check data according to the output state of the power level detection output;
When the check data of the check data generation unit is predetermined predetermined data indicating that the power level detection output is an alternating output, it is determined that the power level is normal, and when the check data is different from the predetermined data, the power level A level determination unit that determines abnormality and stops the transmission function of the wireless terminal at the time of abnormality determination;
Equipped with a,
The power level detection output generation unit is connected to a transmission path of the transmission signal and is periodically switched and controlled, and one end side of each of the first level switches is periodically connected to the first switching switch in parallel with each other. A first signal path without an attenuator, a second signal path with an attenuator interposed therein, and the other end of each of the first and second signal paths that are periodically controlled in synchronization with the first changeover switch. A second change-over switch that is periodically connected to the side, and a signal that is input via the second change-over switch is converted into a direct current, and then the power level detection that generates the power level detection output by performing level test with the threshold value And when the signal is being input via the second signal path, the power level detection unit temporarily controls the signal level to be greater than or equal to the threshold value to increase the second level. No. transmission capability monitoring device, wherein the path is configured to include a confirmation means for confirming whether normal or not. The check data generation unit samples the power level detection output at predetermined time intervals, generates serial data based on the sampling data and prestored reference data, and outputs the serial data as the check data The transmission capability monitoring device according to claim 1 , wherein When both the power level detection output generation unit and the check data generation unit have a dual system configuration, the power level detection output generation unit generates first and second power levels that generate dual power relationship detection outputs. A detection output generation unit, wherein the check data generation unit converts a power level detection output of the first power level detection output generation unit into first check data; and a second power A second check data conversion unit for converting the power level detection output of the level detection output generation unit into second check data different from the first check data; and an output switching unit for alternately switching and outputting the first and second check data The transmission capability monitoring device according to claim 1 , wherein the transmission capability monitoring device is configured to include: The transmission capability monitoring apparatus according to any one of claims 1 to 3 , wherein the level determination unit is provided separately from a wireless terminal. A reception capability monitoring device for monitoring the reception sensitivity of a wireless terminal,
A demodulation signal level of a demodulation circuit that demodulates a reception signal of the wireless terminal is detected, and when it is detected that the signal level has increased by a predetermined level or more, it is determined that reception sensitivity is abnormal and the reception function of the wireless terminal is stopped. With a monitor ,
The monitor unit is
After reception data is acquired based on a reception signal input from a reception antenna to the demodulation circuit, a test signal supply unit that periodically attenuates a test signal and supplies the test signal to the demodulation circuit, and demodulated by the demodulation circuit a power level detection output generation unit that generates a power level detection output as compared with a preset threshold value to a power level between when not attenuate inputs a test signal the input signal and the time of attenuation, the power level detector Received when a check data generating unit that generates check data according to an output state of output and the check data of the check data generating unit is predetermined predetermined data indicating that the power level detection output is an alternating output It is determined that the sensitivity is normal and the received data is valid, and when the check data is different from the predetermined data, the reception sensitivity is abnormal and the received data is invalid. Rutotomoni, and a level determination unit to stop receiving function of the wireless terminal,
The test signal supply unit includes a test signal generation unit that generates a test signal, a first changeover switch that is connected to the test signal generation unit and that is periodically controlled to be switched, and one end side of each of the test signal supply units is parallel to each other. A first signal path without an attenuator periodically connected to the switch and a second signal path with an attenuator interposed therebetween, and the first and second signals are controlled periodically in synchronization with the first changeover switch. A second changeover switch that periodically switches and connects to the other end of each of the two signal paths, and a third changeover switch that switches and connects the input side of the demodulation circuit to the receiving antenna and the second changeover switch,
The power detection output generation unit controls whether the second signal path is normal by increasing the signal level temporarily to be equal to or higher than the threshold when a signal is input via the second signal path. A reception capability monitoring device characterized by comprising confirmation means for confirming whether or not . The signal path for inputting the demodulated test signal of the demodulating circuit to the check data generating unit is provided with a normally open switch that is turned on when the power detection output of the power level detection output generating unit is equal to or higher than a predetermined level, A test signal including test data generated by a check data generation unit is supplied from the test signal supply unit to the demodulation circuit, and the check data generation unit generates switch check data corresponding to the input demodulation test signal, The reception level monitoring device according to claim 5 , wherein the level determination unit includes a configuration that determines that the normally open switch is normal when the switch check data is predetermined data. The check data generation unit samples the power level detection output at predetermined time intervals, generates serial data based on the sampling data and prestored reference data, and outputs the serial data as the check data The reception capability monitoring device according to claim 5 or 6 . When both the power level detection output generation unit and the check data generation unit have a dual system configuration, the power level detection output generation unit generates first and second power levels that generate dual power relationship detection outputs. A detection output generation unit, wherein the check data generation unit converts a power level detection output of the first power level detection output generation unit into first check data; and a second power A second check data conversion unit for converting the power level detection output of the level detection output generation unit into second check data different from the first check data; and an output switching unit for alternately switching and outputting the first and second check data The reception capability monitoring device according to any one of claims 5 to 7 , wherein the reception capability monitoring device is provided. The reception capability monitoring apparatus according to any one of claims 5 to 8 , wherein the level determination unit is provided separately from a wireless terminal. A radio station comprising at least one monitor device of the transmission capability monitor device according to any one of claims 1 to 4 and the reception capability monitor device according to any one of claims 5 to 9 , and at least the other A radio communication system, wherein data communication is performed with a radio station including a monitor device. The radio communication system according to claim 10 , wherein one of the radio stations is a mobile station and the other is a fixed station. 12. The radio communication system according to claim 11 , wherein the radio terminal of the mobile station is a vehicle upper unit mounted on a railway vehicle, and the radio terminal of the fixed station is a ground unit arranged between rails of the rail vehicle.

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