WO2013047450A1 - 無線通信ネットワークシステムの同期方法 - Google Patents
無線通信ネットワークシステムの同期方法 Download PDFInfo
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- WO2013047450A1 WO2013047450A1 PCT/JP2012/074420 JP2012074420W WO2013047450A1 WO 2013047450 A1 WO2013047450 A1 WO 2013047450A1 JP 2012074420 W JP2012074420 W JP 2012074420W WO 2013047450 A1 WO2013047450 A1 WO 2013047450A1
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04J—MULTIPLEX COMMUNICATION
- H04J3/00—Time-division multiplex systems
- H04J3/02—Details
- H04J3/06—Synchronising arrangements
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W56/00—Synchronisation arrangements
- H04W56/001—Synchronization between nodes
- H04W56/0015—Synchronization between nodes one node acting as a reference for the others
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61L—GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
- B61L15/00—Indicators provided on the vehicle or vehicle train for signalling purposes ; On-board control or communication systems
- B61L15/0018—Communication with or on the vehicle or vehicle train
- B61L15/0027—Radio-based, e.g. using GSM-R
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61L—GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
- B61L27/00—Central railway traffic control systems; Trackside control; Communication systems specially adapted therefor
- B61L27/70—Details of trackside communication
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04B—TRANSMISSION
- H04B7/00—Radio transmission systems, i.e. using radiation field
- H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
- H04B7/022—Site diversity; Macro-diversity
- H04B7/026—Co-operative diversity, e.g. using fixed or mobile stations as relays
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W56/00—Synchronisation arrangements
- H04W56/001—Synchronization between nodes
- H04W56/002—Mutual synchronization
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W56/00—Synchronisation arrangements
- H04W56/001—Synchronization between nodes
- H04W56/0025—Synchronization between nodes synchronizing potentially movable access points
Definitions
- the present invention includes a mobile radio device mounted on a mobile body and a plurality of fixed radio devices that are installed along a travel route of the mobile body and relay information sequentially, and these radio devices are in a time division multiple access system.
- BACKGROUND OF THE INVENTION 1 Field of the Invention The present invention relates to a synchronization method between wireless devices in a wireless communication network system that performs communication.
- a wireless communication network that can maintain a synchronized state between wireless devices even when a communication failure occurs between fixed wireless devices that can communicate with each other.
- the present invention relates to a system synchronization method.
- each station is synchronized in order to transmit and receive information using a time division multiple access method. Need to be.
- a synchronization method a synchronization packet transmitted from the base station is simultaneously received by all the radio stations and synchronized, or all stations in the control area simultaneously receive a synchronization signal (for example, a GPS signal).
- a synchronization signal for example, a GPS signal.
- a method of synchronizing can be considered.
- the method using the GPS signal is expensive because it is necessary to install an expensive GPS receiver in every station, and it cannot be used in the tunnel.
- the method of using the synchronization packet is a wireless communication network system in a wide control area where there is a wireless station that does not receive radio waves from the base station, for example, a control area having a one-dimensional extension such as railway train control. Can not be used.
- Patent Document 1 As a synchronization method that can be applied even in a wide control area where there is a radio station that does not receive a radio wave from a base station, it is not necessary to provide a receiver for synchronization signals in all stations.
- all the stations including the radio station that does not receive the radio wave from the base station can be obtained by sequentially relaying and transmitting the synchronization packet transmitted from the base station. Is trying to synchronize.
- the synchronization method described in Patent Document 1 is a method of relaying synchronization packets while sequentially performing wireless communication between adjacent radios on the ground.
- the relay operation of the synchronization packet cannot be performed, and the synchronization state between the radios may not be maintained.
- An object of the present invention is to provide a synchronization method of a wireless communication network that can be maintained.
- the wireless communication network synchronization method includes a mobile wireless device mounted on a mobile body that moves along a predetermined route, and a plurality of wireless wireless devices that are installed adjacent to each other at intervals along the route.
- a wireless communication network system comprising a plurality of fixed wireless devices that communicate with each other wirelessly and relay information from a transmission source to a terminal, and perform communication in a time-synchronized manner so that the mobile wireless device and the fixed wireless device can communicate with each other
- the mobile wireless devices are arranged at the front and rear of the mobile body so that they can communicate with each other, and when the mobile body exists between the fixed wireless devices, the synchronization information between the fixed wireless devices is
- the configuration is such that the two mobile radios mounted on the network can be relayed.
- the transmitting side of the mobile wireless devices at the front and rear of the mobile body receives the synchronization information, transmits the received synchronization information to the other mobile wireless device, and transmits the synchronization information from the other mobile wireless device to the fixed wireless device on the receiving side.
- the synchronization information is relayed by using the two mobile radios of the mobile body.
- a wireless communication network synchronization method comprising: a mobile wireless device mounted on a moving body moving along a predetermined route; and a plurality of wireless wireless devices installed adjacent to each other at intervals along the route.
- a wireless communication network system comprising a plurality of fixed wireless devices that communicate wirelessly and relay information from a transmission source to a terminal, and communicate with time synchronization so that the mobile wireless device and the fixed wireless device can communicate
- At least one of the fixed wireless devices is a base station for transmitting a synchronization packet
- the other fixed wireless device is a relay station that relays a synchronization packet transmitted from the base station.
- the relay station that has transitioned to the synchronization acquisition mode transitions to the synchronization maintenance mode when receiving the synchronization packet.
- the synchronization packet transmission can be performed within the predetermined synchronization packet transmission allocation period determined in advance and the relay station in the synchronization maintenance mode does not receive the synchronization packet exceeds a preset synchronization information update time limit.
- the present invention is characterized in that a transition is made to the synchronization acquisition mode.
- At least one fixed radio device is used as a base station for transmitting synchronization packets, and the synchronization packet transmitted from the base station is relayed using another fixed radio device as a relay station.
- the relay station transitions to the synchronization acquisition mode when the power is turned on and waits for reception of a synchronization packet.
- the relay station in the synchronization acquisition mode receives the synchronization packet, it shifts to the synchronization maintenance mode, becomes in a synchronization state, and can transmit the synchronization packet, and the synchronization packet is transmitted during its own synchronization packet transmission allocation period.
- the relay station in the synchronization maintaining mode shifts to the synchronization acquisition mode when the state in which no synchronization packet is received exceeds a preset synchronization information update time limit.
- the synchronization method of the wireless communication network system of the first invention when two mobile wireless devices that can communicate with each other are arranged at the front and rear of the mobile body, and the mobile body exists between the fixed wireless devices Since the synchronization information transmitted by one fixed wireless device can be relayed to the other fixed wireless device by the two mobile wireless devices of the moving body, for example, the antenna height in the tunnel or the fixed wireless device is Continue relaying synchronization information transmitted from a base station using a mobile radio even when radio wave propagation between fixed radios is hindered by the presence of a moving object, such as in lower cases it can. Therefore, even if the communication between the fixed wireless devices is hindered, the relay of the synchronization information is not interrupted, the loss of synchronization of the wireless devices in the network system can be prevented, and the synchronization state can be maintained.
- the relay station in the synchronization maintaining mode can maintain the synchronization state by receiving the synchronization packet within the synchronization information update time limit. Even if a communication failure occurs in a part of the relay path of the synchronization packet, including the case where radio wave propagation between fixed radios is hindered by the presence of The synchronization state can be maintained by receiving the synchronization packet from the network, and the synchronization of radios in the network system can be prevented.
- 1 is a schematic configuration diagram illustrating an example of a wireless communication network system to which a synchronization method according to the present invention is applied. It is explanatory drawing of the frame structure of the communication operation period of a radio
- FIG. 1 is a schematic configuration diagram showing an example of a wireless communication network system to which a wireless communication network system synchronization method according to the present invention is applied.
- the wireless communication network system includes two train radio devices VRS1 and VRS2 mounted on a train 1 which is a moving body, and a plurality of trackside radio devices WRS1 to WRS7.
- the train radio devices VRS1 and VRS2 are arranged at the front and rear of the train 1, are connected to an on-board device (not shown) mounted on the train 1, and can communicate with each other, for example, wired for wired communication. It is connected by a cable and wirelessly communicates various information with the plurality of along-line radio units WRS1 to WRS7 while moving, and corresponds to a mobile radio unit.
- the train radio device VRS1 is arranged at the rear part of the train and the train radio device VRS2 is arranged at the front part of the train.
- the communication between the train radios VRS1 and VRS2 is not limited to wired communication but may be wireless.
- the trackside radios WRS1 to WRS7 transmit and receive various information to and from the train radios VRS1 and VRS2, and a plurality of them are installed along the railroad track that is the travel route of the train 1 and are adjacent to each other.
- This is a propagation type radio that transmits information while relaying wirelessly.
- the trackside radios WRS1 to WRS7 correspond to fixed radios.
- the intervals between these fixed wireless devices are arranged such that the radio waves reach the next wireless device, for example.
- the number of along-line wireless devices is not limited to seven, but is set to an appropriate number according to the size of the control area of the wireless communication network system.
- the communication control system of the wireless communication network system having such a configuration is, for example, a time division multiple access (TDMA) system, and transmits information while relaying information from an intermediate wireless device to a terminal wireless device.
- This wireless communication network system periodically performs communication operation with one frame shown in FIG. 2 as one cycle, and each wireless device has a predetermined time slot (hereinafter referred to as TS) assigned in advance by setting information in one frame. Only), the transmission operation or the reception operation is controlled.
- TS time slot assigned in advance by setting information in one frame. Only
- the operations of all the radio devices in the communication network are synchronized in a later-described synchronized TS block provided in the frame.
- One frame is divided into a plurality of, for example, 10 windows W0 to W9 (indicated by windows in FIG. 2), and each window W0 to W9 is divided into a plurality of time slot blocks (hereinafter referred to as TS blocks), for example, train radio.
- TS blocks time slot blocks
- Ranging TS block for performing ranging between the aircraft VRS1, VRS2 and the along-wireless radio WRS to be communicated, VRS transmission TS block from which the train radios VRS1, VRS2 are transmission sources, and synchronization of transmission / reception operations of each radio Divided into a TS block for transmission, a WRS transmission TS block whose transmission source is the radios WRS1 to WRS7 along the way, and a TS block for VRS relay for relaying by information transmission from the train radios VRS1 and VRS2.
- each TS block is composed of a predetermined number of TSs.
- the synchronization method of the present embodiment assumes that the radio wave propagation between adjacent radios on the ground is hindered by the train, and uses the two train radios mounted on the front and rear parts of the train to synchronize information. For example, the synchronization packet is relayed to maintain the synchronization state of each radio.
- two of the alongside radio units WRS are set as base stations for transmitting synchronization packets, which are transmission sources of the synchronization packets, and other radios including the two train radio units VRS1 and VRS2 are used.
- the machine is a relay station that relays the synchronization packet transmitted from the base station.
- the base station includes a GPS receiver for receiving a reference time signal, for example, a GPS signal, and the base stations are synchronized with each other by receiving the GPS signal.
- each base station Upon receiving the GPS signal, each base station transmits a synchronization packet during its own transmission allocation period based on the time of a built-in timer.
- the synchronization packet includes, for example, transmission source radio type information (terrestrial radio or on-board radio), transmission time information, current time slot information, operation mode (a synchronization acquisition mode, terrestrial synchronization maintenance mode, which will be described later, On-vehicle synchronization maintenance mode etc.) etc. are included as information for synchronization.
- Each relay station receives the synchronization packet transmitted from the base station, determines whether or not to adopt the packet based on the information in the synchronization packet, and enters the synchronization state when it is adopted.
- the synchronization packet is relayed by updating and transmitting the synchronization packet during its own transmission allocation period.
- FIG. 3 shows the transition of the operation mode from the power-on of the radio station as the relay station in the present embodiment, and the synchronous operation of the present embodiment will be described with reference to FIG.
- the ground radio station in FIG. 3 shows each radio
- the radio station transitions from startup to synchronization acquisition mode when the power is turned on.
- the synchronization acquisition mode is a state of waiting for reception of a synchronization packet that arrives directly from a base station or is relayed by a wireless station.
- a synchronization acquisition mode radio station receives a synchronization packet, it determines that it is adopted based on the synchronization information, and the received synchronization packet is (a) a synchronization packet from a terrestrial synchronization maintenance mode terrestrial radio station. Transition to the ground synchronization maintenance mode, and reset the built-in timer to acquire synchronization. That is, at this time, the wireless station is in a synchronized state.
- the ground synchronization maintenance mode is an operation mode when a synchronization packet relayed without a train radio is received, and indicates an operation mode with high synchronization accuracy.
- the radio station that has transitioned to the terrestrial synchronization maintenance mode transmits a synchronization packet in its own synchronization packet transmission allocation period determined based on the time of the built-in timer that has been reset and started timing.
- the radio station in the terrestrial synchronization maintenance mode receives the synchronization packet again from the terrestrial radio station in the terrestrial synchronization maintenance mode until the time of the timer passes the synchronization information update timeout time as the predetermined synchronization information update time limit. If it is adopted, the ground synchronization maintenance mode is maintained.
- a radio station in synchronization acquisition mode receives and employs a synchronization packet from a ground radio station in (b) on-board synchronization maintenance mode
- (c) receives and employs a synchronization packet from the on-board radio station
- (d) When a synchronization packet is received from another on-board radio station in communication between the on-board radio stations and adopted, the on-board synchronization maintenance mode is entered and the built-in timer is reset. To capture synchronously. At this point, the wireless station is in a synchronized state.
- the on-vehicle synchronization maintenance mode is an operation mode when a synchronization packet relayed via a train radio is received, and is an operation mode with lower synchronization accuracy than the above-mentioned ground synchronization maintenance mode. It shows that there is. This is because there is a possibility that a slight synchronization shift may occur because there is a train radio that moves in comparison with the case of relaying only by a ground radio station.
- the wireless station that has transitioned to the on-vehicle synchronization maintenance mode transmits the synchronization packet and relays the synchronization packet during its own synchronization packet transmission allocation period determined based on the time of the built-in timer that has been reset and started timing.
- a radio station in on-vehicle synchronization maintenance mode maintains on-vehicle synchronization if it receives and uses a synchronization packet from a ground radio station in terrestrial synchronization maintenance mode before the timer counts out a predetermined synchronization information update timeout period. The operation is shifted to the ground synchronization maintenance mode with higher synchronization accuracy than the mode, and the operation in the above-mentioned ground synchronization maintenance mode is performed.
- the on-board synchronization maintaining mode is maintained. If the synchronization packet cannot be received before the timer counts up to the synchronization information update timeout time, it is determined that the synchronization information update timeout has occurred, and the mode is shifted to the synchronization acquisition mode.
- FIG. 4 shows the operation of the on-board radio station and the ground radio station for acquiring and maintaining synchronization according to the synchronization method of the present embodiment, assuming that the radio wave propagation between adjacent radios on the ground is hindered by the train.
- the mode transition state is specifically shown and its operation will be described.
- the terrestrial radio station group A receives the synchronization packet from the base station 1, and the terrestrial radio station group C receives the synchronization packet from the base station 2 and from the synchronization acquisition mode, as shown in FIG. Transition to synchronization maintenance mode.
- the radio waves from the ground radio station group A and the ground radio station group C do not reach the ground radio station group B sandwiched between the train 1 and the train 2.
- the on-board radio station 1F can receive the synchronization packet from the terrestrial radio station group A, and the terrestrial radio station group A relays the synchronization packet from the base station 1 without going through the on-board radio station.
- the upper radio station 1F receives the synchronization packet from the radio station in the terrestrial synchronization maintenance mode, and is in the terrestrial synchronization maintenance mode (in the case of (b) in FIG. 3).
- the on-board radio station 1F and the on-board radio station 1B are connected, for example, by wire so that they can communicate with each other, and the on-board radio station 1B can receive a synchronization packet from the on-board radio station 1F.
- the upper radio station 1B is in the on-vehicle synchronization maintaining mode (in the case of (d) in FIG. 3).
- Each radio station of the ground radio station group B that receives the synchronization packet from the onboard radio station 1B is also in the onboard synchronization maintenance mode (in the case of (c) in FIG.
- Each radio of the ground radio station group B that receives the synchronization packets from the ground radio station group C, the on-board radio stations 2B and 2F of the train 2, and the on-board radio station 2F by receiving the synchronization packet from the base station 2 The same applies to stations.
- the synchronization packet can be relayed using the two train radios mounted on the front and rear parts of the train, so that between the radios adjacent to each other on the ground by the train Even if radio wave propagation is disturbed, the synchronization state of each wireless device can be maintained.
- the radio station in the terrestrial synchronization maintenance mode cannot receive the synchronization packet within the synchronization information update timeout period, the radio station continuously transitions to the on-vehicle synchronization maintenance mode and continues the transmission / reception operation instead of the synchronization acquisition mode.
- the synchronization accuracy is somewhat inferior, the soundness of the entire wireless communication network system can be ensured.
- each radio station can recognize whether it is a synchronization packet relayed via a train radio or a synchronization packet relayed only by a ground radio without a train radio.
- the wireless communication network system can be maintained while grasping the synchronization accuracy. If a plurality of base stations are provided, the synchronization packet can be transmitted from the other base station even if there is a problem in relay transmission of the synchronization packet from one base station due to a failure of the radio station. Can be maintained.
- the radio station acquires and maintains synchronization by using the latest synchronization packet as much as possible. It is desirable to ensure synchronization accuracy. From this viewpoint, it is desirable to use a synchronization packet transmitted from the base station direction for synchronization.
- a synchronization packet transmitted from the base station direction is preferentially used for synchronization.
- the clock level is added as one of the synchronization information of the synchronization packet as determination information for preferentially adopting the synchronization packet transmitted from the base station direction.
- the clock level represents the number of wireless stations through which the received synchronization packet has propagated from the base station.
- the base station clock level is set to zero.
- the clock level of the other radio stations is set to a value larger than the maximum number of radio stations assumed to pass through from the base station in the startup and synchronization acquisition mode of FIG. For example, the numerical value may be larger than the total number of radio stations synchronized in the network system.
- the relay station in the ground synchronization maintenance mode or the on-vehicle synchronization maintenance mode receives the synchronization packet
- the clock level information included in the synchronization packet and the clock level information stored and held by itself are compared, and when the value of the own clock level is larger, it is determined that the synchronization packet is received, and 1 is added to the value of the clock level of the synchronization packet so as to be stored and held as own clock level information.
- the radio station in the synchronization acquisition mode receives the synchronization packet directly from the base station
- the radio station compares the clock level information included in the received synchronization packet with the clock level information held by itself.
- the value of the clock level information included in the synchronization packet directly from the base station is “0”
- the value of the clock level information held by the wireless station that has received the synchronization packet is greater than zero. Therefore, the wireless station that has received the synchronization packet determines that it is a synchronization packet received from the base station direction, adopts it, adds “1” to “0”, and holds it as its own clock level information. .
- the clock level value “1” held by itself is added as clock level information of the synchronization packet to be transmitted. To send.
- the received clock level value is set to “1”. "Is added and held as its own clock level value.
- the clock level of each radio station takes a large value sequentially from the base station direction, even if a synchronization packet is received from the radio station on the opposite side to the base station, it is not adopted.
- the synchronization packet from the base station direction can be preferentially adopted.
- the synchronization packet is received at the base station synchronization packet transmission period (for example, 1 second).
- the base station synchronization packet transmission period for example, 1 second.
- the synchronization packet is received from another route.
- the synchronization information update timeout (for example, 1 minute) causes a transition to the synchronization acquisition mode, so that the synchronization packet is received from another base station direction.
- the synchronization accuracy is deteriorated and the synchronization is lost.
- the synchronization method of the third embodiment is to enable the use of a synchronization packet received from another path within the synchronization information update timeout time even when the synchronization packet from the base station direction cannot be received. is there. For this reason, in the third embodiment, the clock level held by itself is increased by, for example, 1 at an appropriate cycle shorter than the synchronization information update timeout time and longer than the transmission cycle of the synchronization packet.
- the own clock level gradually increases, so that the synchronization packet cannot be received. If the clock level of the station exceeds the clock level value included in the synchronization packet from the other path (for example, the path on the other base station side) within the synchronization information update timeout time, the synchronization packet from the other path Since it can be employed, the synchronization maintaining mode can be maintained without transitioning to the synchronization acquisition mode.
- a fourth embodiment of the synchronization method of the first invention will be described.
- the third embodiment it is possible to maintain the synchronization maintaining mode even when the relay path on the one base station side is troubled, but the clock level value of the wireless station that has become unable to receive the synchronization packet is It may take time to exceed the clock level included in the synchronization packet from another path, and the synchronization information update timeout may occur.
- the fourth embodiment enables synchronization to be maintained more promptly even when a failure occurs in the relay route.
- master time information is added as one piece of synchronization information of a synchronization packet instead of clock level information.
- the master time represents the time when the base station transmits the synchronization packet, that is, the synchronization packet transmission time of the base station, and is the time information determined by the base station and matches between the plurality of base stations. May be used, for example, time information of a GPS signal.
- the wireless station when the wireless station receives the synchronization packet in the ground synchronization maintenance mode or the on-vehicle synchronization maintenance mode, the master time information included in the synchronization packet and the master time information stored and held by itself And compare. When the comparison result is newer in the master time information, the received synchronization packet is adopted, and the master time information of the received synchronization packet is held as the master time information.
- the latest synchronization packet as much as possible among the synchronization packets received from two base stations is adopted. Even if one of the relay routes of the two base stations has trouble, the synchronization maintenance mode is set when the synchronization packet including the master time information that is newer than its own master time information is received from the other base station direction. Will be maintained. As a result, the latest synchronization packet can be adopted more quickly than the synchronization method of the third embodiment that increases the clock level value.
- a fifth embodiment of the first invention will be described.
- the synchronization method of the fifth embodiment uses clock level information and master time information together.
- master time information and clock level information are included in the synchronization packet.
- the received synchronization packet is employed when either of the following conditions (1) and (2) is satisfied.
- the master time information included in the received synchronization packet is newer than the master time information held by itself.
- the master time information included in the received synchronization packet is equal to the master time information held by itself, and the clock level value included in the received synchronization packet is smaller than the clock level value held by itself.
- the latest synchronization packet among the synchronization packets received from two base stations can be adopted, and the synchronization packet from the base station direction is given priority. Can be adopted.
- the base station in each embodiment described above operates as a relay station when the reference time information cannot be received due to a failure of the receiver of the GPS signal or the like.
- FIG. 5 shows the transition of the operation mode from the power-on of the base station, and the operation will be described.
- the base station transitions from startup to the reference time signal capture mode when the power is turned on.
- the reference time signal capture mode the reception of the GPS signal as the reference time signal is waited until a reference time signal reception timeout time as a predetermined reference time signal reception time limit elapses.
- the base station in the reference time signal acquisition mode receives a GPS signal within the reference time signal reception timeout period ((A) in the figure)
- the base station synchronization maintenance mode is indicated, which indicates that the synchronization accuracy is higher than the ground synchronization maintenance mode.
- the base station that has transitioned to the base station synchronization maintenance mode transmits a synchronization packet during its own synchronization packet transmission allocation period based on the time of the built-in timer.
- the base station in the base station synchronization maintenance mode When the base station in the base station synchronization maintenance mode receives the GPS signal again before the reference time signal reception timeout time elapses, the base station resets the built-in timer and maintains the base station synchronization maintenance mode. On the other hand, if the GPS signal is not received within the reference time signal reception timeout time based on the time measured by the built-in timer, it is determined that the reference time signal reception timeout has occurred, and the mode is shifted to the synchronization acquisition mode.
- the mode In the reference time signal acquisition mode, when the GPS signal is not received within the reference time signal reception timeout time, the mode is shifted to the synchronization acquisition mode.
- the base station that has transitioned to the synchronization acquisition mode performs the same operation as the radio station as the relay station shown in FIG. 3, and performs the relay operation of the synchronization packet.
- (a) to (d) in FIG. 3 are indicated as (b) to (e) in FIG.
- the mode is changed to the base station synchronization maintaining mode and returned as the base station.
- the base station synchronization maintenance mode is restored and the base station returns.
- the relay station is in the on-vehicle synchronization maintenance mode as a radio station, if the synchronization packet cannot be received within the synchronization information update timeout time, the mode transits to the reference time signal acquisition mode.
- the base station even when there is a failure in the receiving part of the reference time signal, it becomes possible to operate as a relay station, and as a whole wireless network system, a wireless station that operates as a base station Therefore, the soundness of the entire wireless network system can be improved.
- the synchronization method according to the second aspect of the present invention provides a synchronization packet from another base station when a communication failure occurs in a part of the ground fixed radio and the synchronization packet from one base station cannot be received. By receiving, the synchronization state can be maintained.
- each along-line wireless device WRS is used as synchronization packet transmission base stations that serve as transmission sources of synchronization packets
- the other fixed wireless devices are used as base stations.
- the relay station relays the synchronization packet transmitted from.
- the configuration of each base station and relay station is the same as the configuration described in the first embodiment of the first invention described above, so the description thereof is omitted here.
- FIG. 6 shows the transition of the operation mode from the start-up of the radio station as the relay station in this embodiment, and the synchronous operation will be described with reference to FIG.
- the radio station transitions from startup to synchronization acquisition mode when the power is turned on.
- the synchronization acquisition mode is a state of waiting for reception of a synchronization packet that arrives directly from a base station or is relayed by a wireless station.
- the radio station in the synchronization acquisition mode receives the synchronization packet, it determines that it is adopted based on the synchronization information, transitions to the synchronization maintenance mode, and resets the built-in timer to acquire synchronization. That is, at this time, the wireless station is in a synchronized state.
- the radio station that has transitioned to the synchronization maintenance mode transmits a synchronization packet in its own synchronization packet transmission allocation period determined based on the time of the built-in timer that has been reset and started timing.
- the radio station in the synchronization maintaining mode maintains the synchronization maintaining mode when receiving and adopting the synchronization packet again before the time count of the timer passes the synchronization information update timeout time as the predetermined synchronization information update time limit. .
- the synchronization packet cannot be received before the timer counts up to the synchronization information update timeout period, it is determined that the synchronization information update timeout has occurred, and the mode shifts to the synchronization acquisition mode.
- the radio station in the synchronization maintaining mode adopts the synchronization packet regardless of the relay route of the synchronization packet if the synchronization packet can be received and adopted within the synchronization information update timeout time.
- the synchronization state can be maintained. Therefore, if two base stations are provided and a synchronization packet is transmitted, even if a communication failure occurs in a part of the fixed wireless device, the synchronization state can be maintained without causing loss of synchronization or the like. .
- the base station of this embodiment is also configured to operate as a relay station when the reference time information cannot be received, and FIG. 7 shows the transition of the operation mode from the start-up of such a base station. The operation will be described.
- the base station transitions from startup to the reference time signal capture mode when the power is turned on.
- the reference time signal capture mode the reception of the GPS signal as the reference time signal is waited until a reference time signal reception timeout time as a predetermined reference time signal reception time limit elapses.
- the base station in the reference time signal acquisition mode receives a GPS signal within the reference time signal reception timeout period ((A) in the figure)
- the base station synchronization maintenance indicating that the synchronization accuracy is higher than the above-described ground synchronization maintenance mode. Transition to mode.
- the base station that has transitioned to the base station synchronization maintenance mode transmits a synchronization packet during its own synchronization packet transmission allocation period based on the time of the built-in timer.
- the base station in the base station synchronization maintenance mode When the base station in the base station synchronization maintenance mode receives the GPS signal again before the reference time signal reception timeout time elapses, the base station resets the built-in timer and maintains the base station synchronization maintenance mode. On the other hand, if the GPS signal is not received within the reference time signal reception timeout time based on the time measured by the built-in timer, it is determined that the reference time signal reception timeout has occurred, and the mode is shifted to the synchronization acquisition mode.
- the mode In the reference time signal acquisition mode, when the GPS signal is not received within the reference time signal reception timeout time, the mode is shifted to the synchronization acquisition mode.
- the base station that has transitioned to the synchronization acquisition mode performs the same operation as the radio station as the relay station shown in FIG. 6, and performs the relay operation of the synchronization packet. 6A is shown as (B) in FIG.
- the mode when a GPS signal is received in the synchronization acquisition mode, the mode is changed to the base station synchronization maintaining mode and returned as the base station.
- the base station synchronization maintenance mode is restored when the GPS signal is received.
- the mode transits to the reference time signal acquisition mode.
- the base station even when there is a failure in the receiving part of the reference time signal, it becomes possible to operate as a relay station, and as a whole wireless network system, a wireless station that operates as a base station Therefore, the soundness of the entire wireless network system can be improved.
- FIG. 6 is a configuration in which clock level information is added to a synchronization packet as in the second embodiment of the first invention, and synchronization is performed as in the third embodiment.
- the same operation and effect can be obtained by applying the configuration in which the clock level information and the master time information are added and used together as in the fifth embodiment.
- a GPS signal is used as the reference time information.
- the present invention is not limited thereto, and for example, a highly accurate reference signal generator such as a radio clock is provided in the network system. You may make it take out a reference time signal from here.
Abstract
Description
図1は、本発明に係る無線通信ネットワークシステムの同期方法を適用する無線通信ネットワークシステムの一例を示す概略構成図である。
図1において、無線通信ネットワークシステムは、移動体である列車1に搭載された2台の列車無線機VRS1、VRS2と、複数の沿線無線機WRS1~WRS7と、を備えて構成される。
1フレームは、複数、例えば10個のウインドウW0~W9(図2ではwindowで示す)に分割し、各ウインドウW0~W9は複数のタイムスロットブロック(以下、TSブロックとする)、例えば、列車無線機VRS1、VRS2と通信対象の沿線無線機WRS間の測距を行うための測距TSブロック、列車無線機VRS1、VRS2が送信元になるVRS送信TSブロック、各無線機の送受信動作の同期をとるための同期TSブロック、沿線無線機WRS1~WRS7が送信元となるWRS送信TSブロック、及び、列車無線機VRS1、VRS2からの情報送信により中継動作を行うためのVRS中継用TSブロックに分割して構成する。更に、各TSブロックはそれぞれ所定数のTSで構成する。前記VRS中継用TSブロックを設けたことにより、互いに無線通信可能な沿線無線機WRS間の情報伝達を列車無線機VRS1、VRS2を介して中継可能にしている。
本実施形態の同期方法は、列車により地上の互いに隣合う無線機間の電波伝搬に支障が生じた場合を想定して、列車の前後部に搭載した2つの列車無線機を利用して同期情報として例えば同期用パケットを中継して各無線機の同期状態を維持する構成である。
本実施形態では、基地局方向から伝送される同期用パケットを優先的に採用するための判断情報としてクロックレベルを同期用パケットの同期情報の1つとして付加する。前記クロックレベルは、受信した同期用パケットが基地局から伝搬するまでに経由した無線局の台数を表すものである。そして、基地局のクロックレベルを0とする。それ以外の無線局のクロックレベルは、図3の立ち上げ、同期捕捉モードでは、基地局から伝搬するまでに経由すると想定される最大無線局数よりも大きい値とする。例えば、ネットワークシステムにおいて同期させる全無線局数より大きな数値とすればよい。そして、地上同期維持モード又は車上同期維持モードの中継局は、同期用パケットを受信したとき、当該同期用パケット内に含まれているクロックレベル情報と自身が記憶保持しているクロックレベル情報とを比較し、自身のクロックレベルの値の方が大きいときに同期用パケット受信と判定し、その同期用パケットのクロックレベルの値に1を加算して自身のクロックレベル情報として記憶保持するようにする。
例えば、同期捕捉モードの無線局が、基地局から直接同期用パケットを受信したとすると、無線局は、受信した同期用パケットに含まれるクロックレベル情報と自身の保持するクロックレベル情報を比較する。この場合、基地局から直接同期用パケットに含まれるクロックレベル情報の値は「0」であり、同期用パケットを受信した無線局の保持するクロックレベル情報の値は0より大きい。従って、同期用パケットを受信した無線局は、基地局方向から受信した同期用パケットであると判定して採用すると共に、「0」に「1」を加算して自身のクロックレベル情報として保持する。同期用パケットの受信により地上同期維持モードに遷移した無線局が同期用パケットを送信する際には、自身が保持するクロックレベル値「1」を、送信する同期用パケットのクロックレベル情報として付加して送信する。このようにして、地上同期維持モード及び車上同期維持モードの無線局は、自身のクロックレベルより小さい値のクロックレベル情報を持つ同期用パケットを受信する毎に、受信したクロックレベル値に「1」を加算して自身のクロックレベル値として保持する。
同期用パケットは、基地局の同期用パケットの送信周期(例えば1秒)で受信されるが、基地局方向からの同期用パケットが受信できなくなった場合、他の経路から同期用パケットが受信されてもそのクロックレベル値が小さいとその同期用パケットを採用できず、同期情報更新タイムアウト(例えば1分)により同期捕捉モードに遷移してしまい、別の基地局方向からの同期用パケットの受信を待つようになり、同期精度の悪化や同期外れが起こる虞れがある。
第3実施形態は、一方の基地局側の中継経路に支障を生じた場合でも同期維持モードを維持することは可能であるが、同期用パケットが受信できなくなった無線局のクロックレベル値が、他の経路からの同期用パケットに含まれるクロックレベルよりも上回るまでに時間を要し、同期情報更新タイムアウトに至る場合もある。
第4実施形態では、クロックレベル情報の代わりに、マスタタイム情報を同期用パケットの同期情報の1つとして付加する。マスタタイムは、基地局が同期用パケットを送信したときの時刻、即ち、基地局の同期用パケット送信時刻を表し、基地局が定める時刻情報で複数の基地局間で一致するもので、基地局が受信する基準時刻情報、例えば、GPS信号の時刻情報を用いればよい。
第5実施形態の同期方法は、クロックレベル情報とマスタタイム情報を併用するようにしたものである。第5実施形態は、同期用パケットにマスタタイム情報及びクロックレベル情報を含めるようにする。そして、第5実施形態では、下記の(1)、(2)のいずれかの条件を満たした場合に、受信した同期用パケットを採用する。
(1)受信した同期用パケットに含まれるマスタタイム情報が自身の保持するマスタタイム情報より新しい場合。
(2)受信した同期用パケットに含まれるマスタタイム情報が自身の保持するマスタタイム情報と等しく、かつ、受信した同期用パケットに含まれるクロックレベル値が自身の保持するクロックレベル値より小さい場合。
図5に、基地局の電源立ち上げからの動作モードの遷移を示し、その動作について説明する。
第2の発明の同期方法は、地上の固定無線機の一部に通信障害が生じて一方の基地局からの同期用パケットが受信できなくなった場合に、他の基地局からの同期用パケットを受信することで同期状態を維持できるようにしたものである。
WRS1~WRS7 沿線無線機
VRS1、VRS2 列車無線機
Claims (17)
- 所定のルートに沿って移動する移動体に搭載した移動無線機と、前記ルートに沿って間隔を設けて複数設置され互いに隣合うもの同士で無線通信して送信元から末端まで中継しながら情報を伝達する複数の固定無線機とを備え、前記移動無線機と固定無線機が通信可能に時間同期されて通信を行う無線通信ネットワークシステムにおいて、
前記移動無線機を前記移動体の前部と後部に配置して互いに通信可能とし、固定無線機間に前記移動体が存在するときに、前記固定無線機間の同期情報を、移動体に搭載した前記2つの移動無線機で中継可能な構成としたことを特徴とする無線通信ネットワークシステムの同期方法。 - 前記固定無線機の少なくとも1つを前記同期情報として同期用パケットを送信する基地局とし、他の固定無線機及び前記2つの移動無線機を、前記基地局から送信された前記同期用パケットを中継する中継局とし、これら中継局は、前記移動無線機を介在せずに中継された同期用パケットが周期的に受信されて採用している間は、前記移動無線機を介在して中継された同期用パケットを採用しない請求項1に記載の無線通信ネットワークシステムの同期方法。
- 前記中継局は、電源の投入で同期用パケット受信待ち状態の同期捕捉モードに遷移して、移動無線機を介在せずに中継された同期用パケットを受信したときに同期精度が高いことを示す地上同期維持モードに遷移して予め定められた自身の同期用パケット送信割当期間に同期用パケット送信可能となり、移動無線機を介在して中継された同期用パケットを受信したときに前記地上同期維持モードより同期精度が低いことを示す車上同期維持モードに遷移して予め定められた自身の同期用パケット送信割当期間に同期用パケット送信可能となり、車上同期維持モードの中継局が地上同期維持モードの中継局から同期用パケットを受信したときは地上同期維持モードに遷移する請求項2に記載の無線通信ネットワークシステムの同期方法。
- 前記地上同期維持モード又は車上同期維持モードの中継局は、同期用パケットを受信したとき、当該同期用パケット内に含まれている基地局の同期用パケット送信時刻を示すマスタタイム情報と自身が記憶保持しているマスタタイム情報とを比較し、自身のマスタタイム情報の方が新しいときに同期用パケット受信と判定し、その同期用パケットのマスタタイム情報を自身のマスタタイム情報として記憶保持する請求項3に記載の無線通信ネットワークシステムの同期方法。
- 前記地上同期維持モード又は車上同期維持モードの中継局は、同期用パケットを受信したとき、当該同期用パケット内に含まれている基地局から受信されるまでに経由した中継局の数を表すクロックレベル情報と自身が記憶保持しているクロックレベル情報とを比較し、自身のクロックレベルの値の方が小さいときに同期用パケット受信と判定し、その同期用パケットのクロックレベルの値に1を加算して自身のクロックレベル情報として記憶保持する一方、前記基地局は、同期用パケットの送信元を表すクロックレベル情報が予め記憶され、前記同期捕捉モードの中継局は、基地局から受信されるまでに経由することが想定される最大中継局数よりも大きな値がクロックレベル情報として予め記憶される請求項3又は4に記載の無線通信ネットワークシステムの同期方法。
- 前記地上同期維持モード又は車上同期維持モードの中継局は、同期用パケットを受信したとき、当該同期用パケット内に含まれている基地局の同期用パケット送信時刻を示すマスタタイム情報及び基地局から受信されるまでに経由した中継局の数を表すクロックレベル情報と自身が記憶保持しているマスタタイム情報及びクロックレベル情報とをそれぞれ比較し、受信した同期用パケットのマスタタイム情報の方が新しいとき又はマスタタイム情報が同じ場合には自身のクロックレベルの値の方が小さいときに、同期用パケット受信と判定し、その同期用パケットのマスタタイム情報を自身のマスタタイム情報として記憶保持すると共に、その同期用パケットのクロックレベルの値に1を加算して自身のクロックレベル情報として記憶保持する一方、前記基地局は、同期用パケットの送信元を表すクロックレベル情報が予め記憶され、前記同期捕捉モードの中継局は、基地局から受信されるまでに経由することが想定される最大中継局数よりも大きな値がクロックレベル情報として予め記憶される請求項3に記載の無線通信ネットワークシステムの同期方法。
- 前記車上同期維持モードの中継局は、同期用パケット受信無しの状態が予め設定した同期情報更新制限時間を越えたときに前記同期捕捉モードに遷移する構成とした請求項3に記載の無線通信ネットワークシステムの同期方法。
- 前記車上同期維持モードの中継局は、同期捕捉モードに遷移するまでの間、同期用パケットを受信するまで前記同期情報更新制限時間より短い周期で前記クロックレベルの値を一定値ずつ増加する請求項5に記載の無線通信ネットワークシステムの同期方法。
- 前記基地局は、予め設定した基準時刻信号受信制限時間内に基準時刻信号を受信すると、基地局として同期用パケット送信可能となり,前記基準時刻信号受信制限時間内に基準時刻信号の受信がないときは前記中継局として動作する請求項2に記載の無線通信ネットワークシステムの同期方法。
- 前記基地局は、電源の投入で基準時刻信号受信待ち状態の基準時刻信号捕捉モードに遷移して、前記基準時刻信号受信制限時間内に基準時刻信号を受信すると、前記地上同期維持モードより同期精度が高いことを示す基地局同期維持モードに遷移して予め定められた自身の同期用パケット送信割当期間に同期用パケット送信可能となり、前記基準時刻信号捕捉モード又は前記基地局同期維持モードの基地局は、前記基準時刻信号受信制限時間内に基準時刻信号の受信がないときは前記同期捕捉モードに遷移し、同期捕捉モードの基地局は、前記地上同期維持モードの中継局から同期用パケットを受信したときに地上同期維持モードに遷移し、車上同期維持モードの中継局から同期用パケットを受信したときに車上同期維持モードに遷移し、前記地上同期維持モードの基地局は、前記基準時刻信号を受信したときに前記基地局同期維持モードに遷移する一方、予め設定した同期情報更新制限時間内に同期用パケットを受信しないときは前記車上同期維持モードに遷移し、車上同期維持モードの基地局は、前記同期情報更新制限時間内に同期用パケットを受信しないときは前記基準時刻信号捕捉モードに遷移する請求項9に記載の無線通信ネットワークシステムの同期方法。
- 所定のルートに沿って移動する移動体に搭載した移動無線機と、前記ルートに沿って間隔を設けて複数設置され互いに隣合うもの同士で無線通信して送信元から末端まで中継しながら情報を伝達する複数の固定無線機とを備え、前記移動無線機と固定無線機が通信可能に時間同期されて通信を行う無線通信ネットワークシステムにおいて、
前記固定無線機の少なくとも1つを同期情報として同期用パケットを送信する基地局とし、他の固定無線機を、前記基地局から送信された前記同期用パケットを中継する中継局とし、これら中継局は、電源の投入で同期用パケット受信待ち状態の同期捕捉モードに遷移し、同期捕捉モードに遷移した中継局は、同期用パケットを受信したときに同期維持モードに遷移して予め定められた自身の同期用パケット送信割当期間に同期用パケット送信可能となり、前記同期維持モードの中継局は、同期用パケット受信無しの状態が予め設定した同期情報更新制限時間を越えたときに前記同期捕捉モードに遷移する構成としたことを特徴とする無線通信ネットワークシステムの同期方法。 - 前記同期維持モードの中継局は、同期用パケットを受信したとき、当該同期用パケット内に含まれている基地局の同期用パケット送信時刻を示すマスタタイム情報と自身が記憶保持しているマスタタイム情報とを比較し、自身のマスタタイム情報の方が新しいときに同期用パケット受信と判定し、その同期用パケットのマスタタイム情報を自身のマスタタイム情報として記憶保持する請求項11に記載の無線通信ネットワークシステムの同期方法。
- 前記同期維持モードの中継局は、同期用パケットを受信したとき、当該同期用パケット内に含まれている基地局から受信されるまでに経由した中継局の数を表すクロックレベル情報と自身が記憶保持しているクロックレベル情報とを比較し、自身のクロックレベルの値の方が小さいときに同期用パケット受信と判定し、その同期用パケットのクロックレベルの値に1を加算して自身のクロックレベル情報として記憶保持する一方、前記基地局は、同期用パケットの送信元を表すクロックレベル情報が予め記憶され、前記同期捕捉モードの中継局は、基地局から受信されるまでに経由することが想定される最大中継局数よりも大きな値がクロックレベル情報として予め記憶される請求項11又は12に記載の無線通信ネットワークシステムの同期方法。
- 前記同期維持モードの中継局は、同期用パケットを受信したとき、当該同期用パケット内に含まれている基地局の同期用パケット送信時刻を示すマスタタイム情報及び基地局から受信されるまでに経由した中継局の数を表すクロックレベル情報と自身が記憶保持しているマスタタイム情報及びクロックレベル情報とをそれぞれ比較し、受信した同期用パケットのマスタタイム情報の方が新しいとき又はマスタタイム情報が同じ場合には自身のクロックレベルの値の方が小さいときに、同期用パケット受信と判定し、その同期用パケットのマスタタイム情報を自身のマスタタイム情報として記憶保持すると共に、その同期用パケットのクロックレベルの値に1を加算して自身のクロックレベル情報として記憶保持する一方、前記基地局は、同期用パケットの送信元を表すクロックレベル情報が予め記憶され、前記同期捕捉モードの中継局は、基地局から受信されるまでに経由することが想定される最大中継局数よりも大きな値がクロックレベル情報として予め記憶される請求項11に記載の無線通信ネットワークシステムの同期方法。
- 前記同期維持モードの中継局は、同期捕捉モードに遷移するまでの間、同期用パケットを受信するまで前記同期情報更新制限時間より短い周期で前記クロックレベルの値を一定値ずつ増加する請求項13に記載の無線通信ネットワークシステムの同期方法。
- 前記基地局は、電源の投入で基準時刻信号受信待ち状態の基準時刻信号捕捉モードに遷移して、予め設定した基準時刻信号受信制限時間内に基準時刻信号を受信すると、前記同期維持モードより同期精度が高いことを示す基地局同期維持モードに遷移して予め定められた自身の同期用パケット送信割当期間に同期用パケット送信可能となり、前記基準時刻信号捕捉モード又は前記基地局同期維持モードの基地局は、前記基準時刻信号受信制限時間内に基準時刻信号の受信がないときは前記同期捕捉モードに遷移し、同期捕捉モードの基地局は、同期用パケットを受信したときに前記同期維持モードに遷移し、前記同期維持モードの基地局は、前記基準時刻信号を受信したときに前記基地局同期維持モードに遷移する一方、予め設定した同期情報更新制限時間内に同期用パケットを受信しないときは前記基準時刻信号捕捉モードに遷移する請求項11に記載の無線通信ネットワークシステムの同期方法。
- 前記固定無線機の少なくとも2つを同期用パケット送信用の基地局とする請求項11に記載の無線通信ネットワークシステムの同期方法。
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BR112014007108A BR112014007108A2 (pt) | 2011-09-30 | 2012-09-24 | método de sincronização de sistema de rede de comunicação sem fio |
EP12836999.8A EP2763474B1 (en) | 2011-09-30 | 2012-09-24 | Wireless communication network system synchronization method |
CA2850320A CA2850320C (en) | 2011-09-30 | 2012-09-24 | Wireless communication network system synchronization method |
US14/228,151 US9319163B2 (en) | 2011-09-30 | 2014-03-27 | Wireless communication network system synchronization method |
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JP5814043B2 (ja) | 2011-08-15 | 2015-11-17 | 日本信号株式会社 | 無線通信ネットワークシステム |
UA116025C2 (uk) | 2013-07-04 | 2018-01-25 | Нек Корпорейшн | Система, спосіб і пристрій зв'язку |
CN105723786B (zh) * | 2014-03-21 | 2019-05-10 | 华为技术有限公司 | 一种配置频率资源位置的方法和装置 |
WO2016119890A1 (en) * | 2015-01-30 | 2016-08-04 | Telefonaktiebolaget Lm Ericsson (Publ) | Configuring wireless communications resources |
WO2018025365A1 (ja) * | 2016-08-04 | 2018-02-08 | 三菱電機株式会社 | 無線列車制御システム及び無線列車制御方法 |
JP6733936B2 (ja) * | 2016-10-18 | 2020-08-05 | 住友電工システムソリューション株式会社 | 路側通信機、同期方法、及びコンピュータプログラム |
CN110901691B (zh) * | 2018-09-17 | 2021-10-29 | 株洲中车时代电气股份有限公司 | 一种铁电数据的同步系统、方法和列车网络控制系统 |
CN109367586B (zh) * | 2018-10-19 | 2023-10-17 | 卡斯柯信号有限公司 | 一种城市轨道交通信号系统时钟同步系统及方法 |
US11581632B1 (en) | 2019-11-01 | 2023-02-14 | Northrop Grumman Systems Corporation | Flexline wrap antenna for projectile |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2000102063A (ja) | 1998-09-25 | 2000-04-07 | Nippon Signal Co Ltd:The | 無線通信ネットワークシステムの同期方法 |
JP2009194855A (ja) * | 2008-02-18 | 2009-08-27 | Hitachi Kokusai Electric Inc | 列車無線システム |
JP2010041537A (ja) * | 2008-08-07 | 2010-02-18 | Fujitsu Ltd | 通信端末、基地局、通信端末の通信方法、基地局の通信方法、通信システム |
JP2010171509A (ja) * | 2009-01-20 | 2010-08-05 | Sumitomo Electric Ind Ltd | 路側通信機 |
Family Cites Families (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5420883A (en) * | 1993-05-17 | 1995-05-30 | Hughes Aircraft Company | Train location and control using spread spectrum radio communications |
JP4707212B2 (ja) * | 2000-06-29 | 2011-06-22 | 日本信号株式会社 | 無線通信ネットワークシステム |
US7904085B2 (en) * | 2004-02-23 | 2011-03-08 | Nec Corporation | Mobile device and radio interface arrangement method |
EP1768279A4 (en) * | 2004-07-06 | 2011-01-05 | Panasonic Corp | RADIO COMMUNICATION SYSTEM |
US20060245390A1 (en) * | 2005-04-28 | 2006-11-02 | Yukihiro Omoto | Base station and mobile station constituting mobile communication system |
ES2302438B1 (es) * | 2006-07-10 | 2009-05-21 | Universitat Politecnica De Catalunya | Sistema y procedimiento para enrutar un paquete de datos en una red inalambrica, sistema de computacion en un sistema para enrutar un paquete de datos en una red inalambrica, y procedimiento para enrutar un paquete de datos en un sistema de computacion. |
JP2008062874A (ja) * | 2006-09-11 | 2008-03-21 | Nippon Signal Co Ltd:The | 列車位置検知装置 |
US8843058B2 (en) * | 2007-01-12 | 2014-09-23 | Blackberry Limited | Mobile relay communication system |
WO2008146492A1 (ja) * | 2007-06-01 | 2008-12-04 | Panasonic Corporation | 通信システム、無線通信端末、位置推定装置、通信中継装置並びに接続局 |
JP2009225135A (ja) * | 2008-03-17 | 2009-10-01 | Hitachi Ltd | 列車無線通信システムにおける周波数チャネルの選択方法および車上無線端末 |
US8792367B2 (en) * | 2010-01-21 | 2014-07-29 | Polytechnic Institute Of New York University | CoopMAX: a cooperative MAC with randomized distributed space time coding for an IEEE 802.16 network |
JP5814043B2 (ja) * | 2011-08-15 | 2015-11-17 | 日本信号株式会社 | 無線通信ネットワークシステム |
-
2011
- 2011-09-30 JP JP2011218180A patent/JP5922902B2/ja active Active
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- 2012-09-24 EP EP12836999.8A patent/EP2763474B1/en not_active Not-in-force
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Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2000102063A (ja) | 1998-09-25 | 2000-04-07 | Nippon Signal Co Ltd:The | 無線通信ネットワークシステムの同期方法 |
JP2009194855A (ja) * | 2008-02-18 | 2009-08-27 | Hitachi Kokusai Electric Inc | 列車無線システム |
JP2010041537A (ja) * | 2008-08-07 | 2010-02-18 | Fujitsu Ltd | 通信端末、基地局、通信端末の通信方法、基地局の通信方法、通信システム |
JP2010171509A (ja) * | 2009-01-20 | 2010-08-05 | Sumitomo Electric Ind Ltd | 路側通信機 |
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KR101868996B1 (ko) | 2018-06-20 |
MY170397A (en) | 2019-07-27 |
US9319163B2 (en) | 2016-04-19 |
US20140211782A1 (en) | 2014-07-31 |
IN2014DN03364A (ja) | 2015-06-05 |
CA2850320A1 (en) | 2013-04-04 |
EP2763474A4 (en) | 2015-06-03 |
BR112014007108A2 (pt) | 2017-06-13 |
EP2763474B1 (en) | 2018-07-25 |
CN103843426B (zh) | 2018-05-11 |
JP2013078073A (ja) | 2013-04-25 |
JP5922902B2 (ja) | 2016-05-24 |
EP2763474A1 (en) | 2014-08-06 |
CA2850320C (en) | 2018-05-22 |
KR20140086996A (ko) | 2014-07-08 |
CN103843426A (zh) | 2014-06-04 |
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