JP2007158797A - Train radio interference electronic wave preventing system, base station, and radio terminal in train - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a train radio interference electronic wave preventing system for outputting an alarm relating to transmission source of an interference electronic wave while preventing interruption of a communication caused by the interference electronic wave. <P>SOLUTION: Two or more channels are to be prepared as a CH in a radio frequency band to be used for a communication via a wireless LAN 5 between a base station 2 and a radio terminal within a train. When a burst error in a current CH under communication is detected by a burst error detecting unit 23a in an access controller 23 of the base station 2 or a burst error detecting unit 32 in the radio terminal 3 within the train, switching between a current system and a reserved system is to be performed, such as between access point transmission reception units 24a, 24b of the base station 2 by an access point switching unit 23b in the access controller 23, or between terminal side transmission reception units 31a, 31b of the radio terminal 3 within the train by a transmission reception part switching unit 33 in the radio terminal 3 within the train, while alarm information is to be automatically transmitted from an automatic sound transmission device 21 using the radio frequency band of the burst error generating CH. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a train radio interference radio wave avoidance system, a base station, and an in-train radio terminal, and can be suitably applied particularly to a train radio system that employs an interference radio wave avoidance method for train radio. The present invention can also be applied to a mobile radio system for a mobile radio terminal that moves at high speed outdoors.

  As a conventional train radio system, for example, as disclosed in Japanese Patent Application Laid-Open No. 2001-222603 “Service Providing Method and Service Providing System in a Train” disclosed in Patent Document 1, a plurality of in-vehicle servers provided in a train are used. In-vehicle terminals are connected using an in-vehicle LAN, and further, an in-vehicle server is connected to an information providing system on the ground outside the train via a wireless communication network. The system which acquires and outputs the service which a passenger needs from the information provision system on the ground via is disclosed.

  In this system, an Internet server connected to the Internet is provided in an information providing system outside the train that is connected to an in-vehicle server via a wireless communication network, and each in-vehicle terminal is connected to the in-vehicle server based on passenger operations. An Internet server in the information providing system is activated via the Internet, and a target Web site is searched via the Internet.

  In addition, as another train radio system, for example, as described in Japanese Patent Application Laid-Open No. 2002-111702 “Mobile communication device, mobile communication system, and mobile communication method” disclosed in Patent Document 2, A mobile communication device that executes an on-board communication program, a mobile business device that executes an on-board business program, a train radio system, a train radio central station, a station radio LAN, a station network, and a base station A mobile phone network, a host, and a terrestrial communication server, and a user in communication between a mobile communication device or a mobile business device on a mobile unit and a train radio central station, host, or terrestrial communication server However, there has also been proposed a system that enables seamless communication without being conscious of the communication transmission method and communication state.

Furthermore, as another train radio system, for example, a railway vehicle having an in-vehicle LAN system as described in Japanese Patent Laid-Open No. 10-276217 “Automatic IP address setting method of vehicle LAN terminal” disclosed in Patent Document 3 And a DHCP (Dynamic Host Configuration Protocol) server that manages IP (Internet Protocol) addresses of a plurality of LAN terminals constituting the in-vehicle LAN system, and an operation state including a train staying time. A TTCS (Total Traffic Control System) to be managed is connected to a ground station having a wireless line, and in response to IP address setting requests from a plurality of LAN terminals of the mobile station, the DHCP server manages the train time of the train managed by the TTCS Based on information Set the IP address specifying the IP address validity period (IP address lease time) and also has been proposed a system that notifies the plurality of LAN terminals of the mobile station.
JP 2001-222603 A (page 6-8) JP 2002-111702 A (Page 5-7) JP-A-10-276217 (page 5-6)

  In general, in train radio, there is a possibility that a state in which communication is not possible may occur due to the influence of interference radio waves such as illegal radio. However, in the prior arts described in Patent Documents 1 to 3 described above, even if the current wireless communication is hindered due to interference radio waves such as illegal radio, it is illegal to switch the ground station. There is no function of automatically selecting and connecting a ground station using another radio frequency band that is not affected by radio, and the problem that current data communication cannot be continued cannot be solved.

  In addition, it is not possible to resolve the situation where the radio frequency band used at the source of the interference radio wave such as illegal radio is currently being used for business as a train radio and continues to transmit. There is also a problem.

  Therefore, the present invention has been made in view of such a problem, and even if interference caused by illegal radio or the like occurs, train radio communication can be continued and the source of jamming radio waves such as illegal radio can be maintained. The object is to provide means for transmitting a warning message by voice or data.

  That is, the present invention makes a wireless LAN (Local Area Network) connection between a wireless terminal in a train and a plurality of access points arranged at regular intervals along a track along which the train moves, and at regular intervals. Via one of the access points of the plurality of deployed base stations, it is deployed in the base station and connected to an access controller that performs overall control of the base station. In a train radio system connected to various server groups installed in a station, a plurality of CHs having different radio frequency bands used between radio terminals and access points in the train, for example, 2CH (2.4 GHz band and 5 GHz band 2CH ( The purpose is to perform the following control.

  In other words, when a burst error is detected during data communication using one of the two or more channels as the active CH, the data communication is switched to a different CH from the active CH and using a different radio frequency band. , While starting the automatic voice transmission device and automatic data transmission device, using the radio frequency band of the active CH before switching, that is, the error radio frequency band, to send a warning message by voice or data train radio interference The object is to provide a radio wave avoidance system, a base station, and an in-train wireless terminal.

  In order to solve the above-described problems, the train radio interference radio wave avoidance system, the base station, and the in-train radio terminal according to the present invention employ the following characteristic configuration.

(1) Movement of the train between the in-train radio terminal provided in the moving train and any one of a plurality of base stations arranged at regular intervals along the track on which the train moves Accordingly, the communication using the radio channel in the radio frequency band is interrupted by the interference radio wave with respect to the train radio communication performed using the radio channel (CH) in the radio frequency band while switching the base stations one after another. In the train radio interference radio wave avoidance system, two CHs having different radio frequency bands are provided as radio CHs of the radio frequency band used for communication between the in-train radio terminal and the base station. Any one of the CHs is assigned as a working CH to a wireless CH in the radio frequency band used for communication between the in-train radio terminal and the base station, and assigned to the working CH. Switching means for switching the active CH in which a burst error has occurred to a CH of a radio frequency band different from the active CH when a burst error is detected during communication using the radio CH of the applied radio frequency band; and the burst A train radio interference avoidance system comprising: warning transmission means for transmitting warning information using a radio frequency band of the working CH in which an error has occurred.
(2) In place of two CHs having different radio frequency bands, two or more CHs having different radio frequency bands are provided, and the switching unit uses any one of the two or more CHs as active If a burst error is detected when a CH is assigned to a radio CH in the radio frequency band used for communication between the in-train radio terminal and the base station as a CH, the working CH in which the burst error has occurred is assigned to two or more CHs. Among these, the train radio interference radio wave avoidance system according to (1) above, which switches to a CH in a radio frequency band different from the working CH in a predetermined order.
(3) The base station further includes authentication means for performing terminal authentication as to whether or not to permit communication from the in-train wireless terminal, and when receiving an authentication request from the in-train wireless terminal, The means determines whether or not the terminal is permitted to communicate, and if it is determined that the terminal is permitted to communicate, connects the wireless terminal in the request source to the communication network via the base station. In addition, the train radio interference radio wave avoidance system according to (1) or (2), wherein the completion of the authentication is returned to the requesting radio terminal in the train.
(4) When the base station receives an IP (Internet Protocol) address acquisition request from the in-train wireless terminal that has returned the completion of authentication, the base station manages DHCP (Dynamic Host Configuration Protocol). The train radio interference radio wave avoidance system according to (3), wherein the system is connected to a server via the communication network, and the assigned IP address is returned from the DHCP server to the in-train radio terminal as a request source.
(5) The train radio interference radio wave avoidance system according to any one of (1) to (4), wherein the warning transmission means automatically transmits a warning message or warning signal based on voice and / or data as the warning information.
(6) In a base station that communicates with a radio terminal in a train provided in a moving train using a radio channel (CH) in a radio frequency band, communication with the radio terminal in the train As radio CHs of the radio frequency band used in the above, two CHs having different radio frequency bands are provided, and one of the two CHs is used as a working CH for communication with the in-train radio terminal When a burst error is detected during communication using the radio channel of the radio frequency band assigned to the radio channel in the radio frequency band and assigned to the active channel, the active CH in which the burst error has occurred is different from the active CH. Switching means for switching to a frequency band CH and a warning sender for transmitting warning information using the radio frequency band of the working CH in which the burst error has occurred Base station and a and.
(7) Instead of two CHs having different radio frequency bands, two or more CHs having different radio frequency bands are provided, and the switching unit uses any one of the two or more CHs as active When a burst error is detected when a CH is assigned to a radio CH in the radio frequency band used for communication with the in-train radio terminal as a CH, the working CH in which the burst error has occurred is selected from among two or more CHs. The base station according to (6), which switches to a CH in a radio frequency band different from the working CH in a predetermined order.
(8) It further comprises authentication means for performing terminal authentication as to whether to permit communication from the in-train wireless terminal, and when receiving the authentication request from the in-train wireless terminal, the authentication means If it is determined whether or not the terminal can be permitted, and if it is determined that the terminal is capable of communication, the request source is connected to the communication network via the base station and the authentication is completed. The base station according to (6) or (7) above, which returns a message to the requesting wireless terminal in the train.
(9) When an IP (Internet Protocol) address acquisition request is received from the in-train wireless terminal that has sent back the completion of authentication, the communication network is connected to a DHCP (Dynamic Host Configuration Protocol) server that manages IP address assignment. The base station according to (8), wherein the base station is connected through the DHCP server and causes the DHCP server to return the assigned IP address to the in-train wireless terminal that is the request source.
(10) The base station according to any one of (6) to (9), wherein the warning transmission unit automatically transmits a warning message or a warning signal based on voice and / or data as the warning information.
(11) In a train radio terminal that is provided in a moving train and communicates with a base station using a radio channel (CH) in a radio frequency band, it is used for communication with the base station. As the radio CH of the radio frequency band, two CHs having different radio frequency bands are provided, and one of the two CHs is used as a working CH for communication with the base station. When a burst error is detected during communication using the radio channel in the radio frequency band assigned to the radio CH and assigned to the active CH, the active CH in which the burst error has occurred is changed to a CH in a radio frequency band different from the active CH. In-train wireless terminal provided with switching means for switching to.
(12) In place of two CHs having different radio frequency bands, two or more CHs having different radio frequency bands are provided, and the switching unit uses any one of the two or more CHs as active When a burst error is detected when a CH is assigned to a radio CH in the radio frequency band used for communication with the base station as a CH, the working CH in which a burst error has occurred is assigned to the working CH among two or more CHs. (11) The in-train wireless terminal that switches to a CH in a different radio frequency band in a predetermined order.

  According to the train radio interference radio wave avoidance system, the base station, and the in-train radio terminal of the present invention, by providing at least 2 CH of radio frequency bands used between the radio terminal in the train and the access point, Can produce various effects.

  The first effect is that any one of two or more CHs having different radio frequency bands is used as a working CH for communication between the in-train radio terminal and the base station. Even if communication in the radio frequency band of the currently used CH is interrupted between the radio terminal in the train and the base station due to the jamming radio wave, the communication is automatically performed by switching to another radio frequency band CH. Is to be able to resume.

  The second effect is that, by activating the automatic voice transmitting device or the automatic data transmitting device, the warning message / warning signal by voice or data can be used as the working CH to the source of the interfering radio wave such as illegal radio. Since it is transmitting using the same frequency band as the radio frequency band used, that is, the radio frequency band of illegal radio waves etc., illegal radio etc. to the user who is the source of illegal radio waves It is possible to make it possible to notice that the disturbing radio wave is being transmitted and to stop the transmission of the disturbing radio wave such as illegal radio. As a result, the user of the source of jamming radio waves such as illegal radio will be able to eliminate the state where he / she continues to transmit without being aware of the fact that the radio frequency being used is being used for train radio work. be able to.

  Hereinafter, preferred embodiments of a train radio interference radio wave avoidance system, a base station, and an in-train radio terminal according to the present invention will be described with reference to the accompanying drawings.

(Configuration example)
FIG. 1 is a system configuration diagram illustrating an example of a configuration of a train radio interference radio wave avoidance system according to the present invention. As shown in FIG. 1, a train radio interference radio wave avoidance system 100, which is an example of the present invention, includes a central station 1, a plurality of base stations 2, a plurality of base stations 2, and a radio terminal 3 in a train, a communication network 4, Each is configured by being connected by a LAN (Local Area Network) 5. The central office 1 includes at least a router 11, a DHCP (Dynamic Host Configuration Protocol) server 12, and an application server 13. Each of the plurality of base stations 2 includes an automatic voice transmission device 21, a router 22, and an access controller 23. The access point 24 is built in at least.

  In the train radio interference radio wave avoidance system 100 shown in FIG. 1, in-train radio terminals 3 provided in a moving train, and in a plurality of base stations 2 arranged at regular intervals along a track along which the train moves. The connection with the wireless LAN 5 is performed while switching the connection of the access points 24 one after another according to movement.

  The access points 24 of the plurality of base stations 2 are connected to an access controller 23 installed in each base station 2. Thereby, a request from the in-train wireless terminal 3 is transmitted to the access controller 23. The access controller 23 that has received the request from the in-train wireless terminal 3 controls the router 22 in each base station 2 based on the result of interpreting the request, and wired via the router 22 in each base station 2. Alternatively, it is connected to the router 11 of the central office 1 via a communication network 4 made up of wireless or the like.

  Further, the router 11 of the central office 1 receives a request from the in-train wireless terminal 3 input via the access controller 23 and connects to the DHCP server 12 or the application server 13 installed in the central office 1. To do. As a result, it is connected to the DHCP server 12 and the application server 13 in the central station 1 requested from the in-train radio terminal 3. The application server 13 is also connected to an external network such as the Internet. When a connection request to a website on the Internet is received from the in-train wireless terminal 3, the application server 13 is connected to the Internet via the application server 13. Connect to the website.

  A plurality of CHs (Channels) having different radio frequency bands used in the wireless LAN 5 interposed between the in-train wireless terminal 3 and the access point 24 of each base station 2, for example, 2 CH portions of 2.4 GHz band and 5 GHz band The access controller 23 prepares a burst error when a burst error is detected, and a burst error detection unit 23a that detects a burst error over a radio level from the access point 24 and a predetermined time or more. The access point 24 is controlled to switch between the working CH and the spare CH, and the spare CH having a frequency band different from the radio frequency band of the working CH in which the burst error is detected is used as the new working CH. And an access point switching unit 23b.

  When a burst error is detected, the access controller 23 activates the automatic voice transmitting device 21 provided in the base station 2 and reserves the CH of the radio frequency band in which the burst error has occurred (that is, the standby by the occurrence of the burst error). It has a function of sending a warning message by voice to the wireless LAN 5 in a broadcast format using CH) switched to the system.

  Here, as described above, between the wireless terminal 3 in the train and the access point 24 wirelessly connected via the wireless LAN 5, data communication is interrupted due to illegal radio waves emitted by the illegal radio station 6. In order to avoid it, for example, a 2CH radio line is prepared, and any two radio waves in two different radio frequency bands can be transmitted and received. Therefore, as shown in FIG. 1, each access point 24 of each base station 2 includes two access point transmission / reception units 24a and 24b that transmit and receive communication information corresponding to each radio wave in the 2CH radio frequency band. It has been.

  Under the control of the access point switching unit 23b of the access controller 23 in each base station 2, one of the access point transmission / reception units 24a, for example, can be operated, and the other, for example, the access point transmission / reception unit 24b can be operated for backup.

  Here, in the state where data communication is performed with the access point transmission / reception unit 24a as active and the access point transmission / reception unit 24b as backup, the burst error detection unit 23a of the access controller 23 uses the access point transmission / reception unit 24a of the active CH. When a burst error is detected in the received data, the access point transmission / reception unit 24b that is on standby for standby is set as active and the access point transmission / reception unit 24a in which a burst error is detected is set as standby under the control of the access point switching unit 23b. By switching to, the data communication being executed can be continued without interruption.

  The in-train wireless terminal 3 is also provided with two terminal-side transmission / reception units 31a and 31b that can transmit and receive each radio wave in the 2CH radio frequency band, similarly to the base station 2 side. A burst error detection unit 32 for detecting a burst error over a predetermined time, and the terminal side transmission / reception units 31a and 31b in which a burst error has occurred when a burst error is detected, And a transmission / reception unit switching unit 33 that performs control so that a standby CH having a frequency band different from the radio frequency band of the working CH in which the burst error is detected is used as a new working CH.

  In the in-train radio terminal 3, one of the terminals, for example, the terminal-side transceiver 31 a can be used as the active side, and the other, for example, the terminal-side transceiver 31 b can be operated as the standby, under the control of the transceiver unit 33.

  Here, the terminal side transmission / reception unit 31a is used as the active side, and the terminal side transmission / reception unit 31b is used as the backup side, and data transmission is performed in the burst error detection unit 32 on the in-train radio terminal 3 side, and the terminal side transmission / reception of the active CH When a burst error is detected in the data received by the unit 31a, the terminal-side transmission / reception unit 31a in which the burst error is detected is switched to the active terminal-side transmission / reception unit 31b as a backup by control of the transmission / reception unit switching unit 33. By switching to the standby mode, the data communication being performed can be continued on the in-train radio terminal 3 side without being interrupted.

(Description of operation)
Next, an example of the operation of the train radio interference radio wave avoidance system 100 shown in FIG. 1 will be described in detail with reference to the sequence chart of FIG. FIG. 2 is a sequence chart showing an example of the operation of the train radio jamming avoidance system according to the present invention, for explaining the data transfer operation in the train radio jamming avoidance system 100 which is an example of the present invention shown in FIG. It is a sequence chart.

  First, the in-train wireless terminal 3 installed in the moving train uses a radio frequency band of one of the working CHs out of the 2CH radio frequency bands, and is installed at a plurality of intervals along the track. A search command for searching for an access point 24 that is closest to the current train position among the access points 24 in the base station 2 is transmitted via the wireless LAN 5 (sequence S1).

  The access point 24 that has received the search command from the in-train radio terminal 3 through the access-side access point transmission / reception unit 24a that receives radio waves in the radio frequency band of the current CH is the radio terminal in the train that is the source of the search command. 3 returns a response signal via the wireless LAN 5 (sequence S2). As a result, the in-train wireless terminal 3 is connected to the access controller 23 in the base station 2 in which the access point 24 that has transmitted the response signal is installed.

  The in-train wireless terminal 3 transmits a wireless LAN connection authentication request to the connected access controller 23 (sequence S3). The authentication means provided in the access controller 23 that has received the authentication request identifies the in-train radio terminal 3 and checks whether or not the terminal is permitted to be connected. If the authentication is possible, the access point 24 wirelessly connected to the in-train wireless terminal 3 is connected to the router 22 via the access controller 23 (sequence S4).

  Thereafter, the access controller 23 notifies the in-train wireless terminal 3 that is the transmission source of the authentication request that the authentication is completed (sequence S5).

  The in-train wireless terminal 3 that has received the notification of the completion of authentication transmits an IP (Internet Protocol) address acquisition request to the base station 2 connected via the wireless LAN 5. Under the control from the network, the DHCP server 12 of the central office 1 is requested to acquire an IP address via the communication network 4 via the router 22 connected to the access point 24 via a line (sequence S6). Upon receiving the request, the DHCP server 12 selects a payable IP address and returns the selected IP address to the in-train wireless terminal 3 (sequence S7).

  The in-train wireless terminal 3 starts data communication with a desired communication partner via the router 22 of the base station 2 using the acquired IP address as the source address of the communication source (sequence S8).

  For example, when it is desired to connect to a website on the Internet, the in-train wireless terminal 3 uses the IP address of the website on the Internet as the destination address of the communication partner and accesses the access point 24 of the base station 2. Send. As a result, the IP address transmitted as the destination address is transmitted to the central station 1 via the access point 24, the access controller 23, and the router 22 of the base station 2, and further transmitted as the destination address. If it is determined that the received IP address is not an address in the central office 1, a connection request is transmitted to the Internet from the router 11 of the central office 1 via the application server 13 via the communication network 4. The Thus, the in-train radio terminal 3 is connected to a desired website on the Internet.

  Next, in the case where the in-train wireless terminal 3 is transmitting / receiving data to / from the access point 24 using a radio wave in one of the 2CH radio frequency bands and the active CH radio frequency band, A data communication recovery method in the case where a burst error is detected due to an illegal radio wave from the illegal radio station 6 and data communication cannot be performed will be described.

  For example, as shown in FIG. 1, using the access point transmission / reception unit 24a of the access point 24 of the base station 2 and using radio waves in the radio frequency band of the working CH, the terminal-side transmission / reception unit 31a of the in-train wireless terminal 3 When an interference radio wave such as illegal radio is transmitted from the illegal radio station 6 in the same radio frequency band as the radio radio wave of the working CH while data is being transmitted / received to / from the base station, The transfer operation of data transmitted / received between the access point 24 of 2 and the in-train wireless terminal 3 is obstructed, and finally a predetermined time (predetermined as a time during which normal data communication cannot be continued). Burst error occurs over a certain period of time), and normal data transmission / reception cannot be performed.

  When the occurrence of such a burst error is detected by the burst error detection unit 23a on the base station 2 side, the access point switching unit 23b of the access controller 23 that controls the access point 24 of the base station 2 By switching between the CH and the standby CH, the access point transmission / reception unit 24a used for the CH that has been used up to now is set to the standby side, and at the same time, is disconnected as an abnormal system, and the radio frequency that has been newly changed from the standby CH to the current CH It sets to the state which restarts the transmission / reception operation | movement of the data between the radio | wireless terminals 3 in a train using the access point transmission / reception part 24b which transmits / receives the radio | wireless radio wave of a belt | band | zone.

  On the other hand, when such a burst error is detected by the burst error detection unit 32 on the in-train wireless terminal 3 side, the transmission / reception unit switching unit 33 of the in-train wireless terminal 3 switches between the current CH and the standby CH, The terminal side transmission / reception unit 31b for transmitting / receiving radio waves in the radio frequency band newly set as the working CH from the standby use is separated from the abnormal system at the same time as the terminal side transmission / reception unit 31a used for the currently used CH is made the standby side. Is used to resume data transmission / reception with the access point 24 on the base station 2 side.

  Alternatively, when the transmission / reception unit switching unit 33 of the in-train wireless terminal 3 resumes data communication by the terminal-side transmission / reception unit 31b that transmits / receives radio waves in the radio frequency band that has newly become the working CH, the base that can be used again. You may control to transmit the search command which searches the access point 24 of the station 2. In this case, when a response signal to this new radio frequency band search command is received from the access point 24 on the base station 2 side, data communication can be resumed according to the sequence chart of FIG.

  When such a burst error is detected on the base station 2 side, as described above, the access controller 23 to which the access point 24 of the base station 2 is connected is installed in the base station 2. By using the access point transmission / reception unit 24a that has been separated as an abnormal system by generating a burst error by controlling the automatic voice transmission device 21, it is automatically performed using radio waves in the radio frequency band of the CH that has been used so far. A warning message by voice from the voice transmission device 21 is automatically transmitted.

  This warning message indicates that data communication for train radio is impossible due to jamming radio waves, and that the user of illegal radio station 6 that is the source of the jamming radio waves should be stopped immediately. In order to warn you, it will be sent in broadcast format. Furthermore, since this warning message is transmitted using a radio frequency band in which a burst error has occurred, the warning message is received by the illegal radio station 6 that is transmitting an interference radio wave such as illegal radio, and the illegal radio station 6 The user can be notified that the jamming radio wave is being transmitted.

  In the above embodiment, the case where the automatic voice transmitting device 21 is activated and the warning message by voice is transmitted to the illegal radio station 6 that is the source of the illegal radio is shown, but the present invention is only in such a case. It is not limited to. For example, an automatic voice transmission device provides a warning transmission means for automatically transmitting warning information for warning of the suspension of illegal radio wave transmission, and data in any format, not voice, as a warning message An automatic data transmitter capable of automatically transmitting may be used in place of the automatic voice transmitter, or warning information may be automatically transmitted using both voice and data. Alternatively, a warning signal such as a warning buzzer sound or a warning control signal may be automatically transmitted.

  Further, the case where two CHs are used as communication CHs has been described, but the configuration is not limited to only two CHs, and two or more CHs having different radio frequency bands are used, and access point switching is performed. The unit 23b and the transmission / reception unit switching unit 33 can be controlled to sequentially switch in a predetermined order. Furthermore, the communication performed by the in-train wireless terminal 3 is not limited to data communication, and may be voice communication or image communication. Furthermore, these communication media are mixed. It does not matter even if it is composite communication.

(Explanation of effect)
Next, effects of the above-described train radio interference radio wave avoidance system 100, the base station 2, and the in-train radio terminal 3, which are examples of the present invention, will be described.

  Since the first effect is configured to use one of two or more CHs having different radio frequency bands as working CHs for communication between the in-train radio terminal 3 and the base station 2, Even if communication using the radio frequency band of the currently used CH between the in-train radio terminal 3 and the base station 2 is interrupted due to interference radio waves such as illegal radio, the channel is switched to another radio frequency band CH. Thus, communication can be automatically resumed.

  The second effect is that, by activating the automatic voice transmitting device 21 and the automatic data transmitting device, a warning message / warning signal by voice or data is sent to the working CH up to the source of the interference radio wave or the like. Since the radio frequency band used as the radio frequency band, that is, the radio frequency band of the illegal radio is transmitted using the same frequency band, the user of the illegal radio station 6 that is the source of the interference radio wave such as illegal radio, It is possible to make it possible to notice that an interfering radio wave such as illegal radio is being transmitted, and to stop the transmission of an interfering radio wave such as illegal radio. As a result, the user of the illegal radio station 6 that is the source of the interfering radio waves such as illegal radio can transmit without knowing that the radio frequency being used is being used in the service of train radio. It is possible to cancel the state of continuing.

  The configuration of the preferred embodiment of the present invention has been described above. However, it should be noted that such examples are merely illustrative of the invention and do not limit the invention in any way. Those skilled in the art will readily understand that various modifications and changes can be made according to a specific application without departing from the gist of the present invention.

It is a system configuration diagram showing an example of a configuration of a train radio interference radio wave avoidance system of the present invention. It is a sequence chart which shows an example of operation | movement of the train radio interference radio wave avoidance system by this invention.

Explanation of symbols

1 Central station 2 Base station 3 Wireless terminal in train 4 Communication network 5 Wireless LAN
6 Illegal Radio Station 11 Router 12 DHCP Server 13 Application Server 21 Automatic Voice Transmitter 22 Router 23 Access Controller 23a Burst Error Detection Unit 23b Access Point Switching Unit 24 Access Point 24a, 24b Access Point Transmission / Reception Unit 31a, 31b Terminal Side Transmission / Reception Unit 32 Burst error detection unit 33 Transmission / reception unit switching unit 100 Train radio interference radio wave avoidance system

Claims (12)

  According to the movement of the train between the radio terminal in the train provided in the moving train and any one of a plurality of base stations arranged at regular intervals along the track on which the train moves While changing the connection of the base stations one after another, disruption of communication using the wireless CH of the radio frequency band is avoided by the interference radio wave with respect to the train radio communication performed using the wireless CH (Channel) of the radio frequency band. In the train radio interference radio wave avoidance system, the radio frequency band wireless CH used for communication between the in-train radio terminal and the base station includes two CHs having different radio frequency bands from each other. Any one of these CHs is assigned as a working CH to a wireless CH in the radio frequency band used for communication between the in-train radio terminal and the base station, and assigned to a working CH When a burst error is detected during communication using the radio channel in the radio frequency band, switching means for switching the active CH in which the burst error has occurred to a CH in a radio frequency band different from the active CH, and the burst error A train radio interference radio wave avoiding system, comprising: warning transmission means for transmitting warning information using a radio frequency band of the generated working CH.   Instead of two CHs having different radio frequency bands, two or more CHs having different radio frequency bands are provided, and the switching means uses any one of the two or more CHs as an active CH. When a burst error is detected when assigned to a radio CH in the radio frequency band used for communication between an in-train radio terminal and the base station, the working CH in which the burst error has occurred is out of two or more CHs. The train radio interference radio wave avoidance system according to claim 1, wherein the train radio interference radio wave avoiding system is switched to a CH in a radio frequency band different from the active CH in a predetermined order.   The base station further comprises authentication means for performing terminal authentication as to whether to permit communication from the in-train wireless terminal, and when receiving an authentication request from the in-train wireless terminal, the authentication means, When determining whether it is a terminal that can permit communication, when determining that it is a terminal that can permit communication, while connecting the wireless terminal in the train of the request source to the communication network through the base station, The train radio interference radio wave avoidance system according to claim 1 or 2, wherein an authentication completion message is returned to the requesting radio terminal in the train.   When the base station receives an acquisition request for an IP (Internet Protocol) address from the in-train wireless terminal that has sent back the completion of the authentication, the base station sends the request to a DHCP (Dynamic Host Configuration Protocol) server that manages IP address assignment. 4. The train radio interference radio wave avoidance system according to claim 3, wherein the train radio interference radio wave avoiding system is connected via a communication network, and the assigned IP address is returned from the DHCP server to the in-train radio terminal of the request source. .   5. The train radio interference radio wave avoidance system according to claim 1, wherein the warning transmission means automatically transmits a warning message or a warning signal based on voice and / or data as the warning information. .   In a base station that communicates with a radio terminal in a train using a radio frequency band radio channel (CH), the base station that is used for communication with the in-train radio terminal The radio frequency band includes two CHs having different radio frequency bands as radio CHs, and uses one of the two CHs as an active CH for communication with the in-train radio terminal. When a burst error is detected during communication using the radio channel of the radio frequency band assigned to the active CH and the radio channel of the radio frequency band assigned to the active CH, the active CH in which the burst error has occurred is assigned to a radio frequency band different from the active CH. Switching means for switching to CH, warning sending means for sending warning information using the radio frequency band of the working CH in which the burst error has occurred, Base station characterized in that it comprises.   Instead of two CHs having different radio frequency bands, two or more CHs having different radio frequency bands are provided, and the switching means uses any one of the two or more CHs as an active CH. When a burst error is detected when assigned to a radio channel in the radio frequency band used for communication with a radio terminal in a train, the working CH in which a burst error has occurred is referred to as the working CH among two or more CHs. The base station according to claim 6, wherein the base station is switched to a CH in a different radio frequency band in a predetermined order.   It further comprises authentication means for performing terminal authentication as to whether or not communication from the in-train wireless terminal is permitted, and when receiving an authentication request from the in-train wireless terminal, the authentication means can permit communication. If it is determined whether or not the terminal is a terminal that is allowed to communicate, the in-train wireless terminal of the request source is connected to the communication network via the base station, and the fact that the authentication is completed The base station according to claim 6 or 7, wherein the base station returns the request to the in-train radio terminal.   When an IP (Internet Protocol) address acquisition request is received from the in-train wireless terminal that has sent back the completion of authentication, a DHCP (Dynamic Host Configuration Protocol) server that manages the allocation of IP addresses is connected via the communication network. The base station according to claim 8, wherein the base station is connected, and the assigned IP address is returned from the DHCP server to the in-train wireless terminal as a request source.   10. The base station according to claim 6, wherein the warning transmission unit automatically transmits a warning message or warning signal based on voice and / or data as the warning information.   The radio frequency used in communication with the base station in a radio terminal in a train that is provided in a moving train and communicates with a base station using a radio channel (CH) in a radio frequency band As the wireless CH of the band, two CHs having different radio frequency bands are provided, and one of the two CHs is used as a working CH for the wireless CH of the radio frequency band used for communication with the base station. Switching when a burst error is detected during communication using the radio channel of the radio frequency band assigned to the active CH, switching the active CH in which the burst error has occurred to a CH of a radio frequency band different from the active CH A radio terminal in a train comprising means.   Instead of two CHs having different radio frequency bands, two or more CHs having different radio frequency bands are provided, and the switching means uses any one of the two or more CHs as an active CH. When a burst error is detected when assigned to a radio channel in the radio frequency band used for communication with a base station, the working CH in which the burst error has occurred is a radio different from the working CH among two or more CHs. The in-train radio terminal according to claim 11, wherein switching to a frequency band CH is performed in a predetermined order.

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