JP6970567B2 - Base station equipment and wireless communication system - Google Patents

Description

The present invention relates to a base station device and a wireless communication system that perform wireless communication with an on-board station device mounted on a train.

In the FDMA (Frequency Division Multiple Access) type wireless communication system (hereinafter referred to as "FDMA radio system") according to the conventional private railway common specifications, the base station devices use different frequencies from each other. A plurality of radios were provided, and each radio was provided with a power supply unit for supplying power to the radio. That is, the base station device of the FDMA radio system is provided with a radio for each frequency, and has a power supply structure for each radio. Therefore, the FDMA radio system that requires four waves includes five radios including a common spare radio, and therefore requires five power supplies.

In wireless communication systems for trains, power saving of base station equipment, on-board station equipment, etc. is being studied. For example, Patent Document 1 discloses an invention in which when the power supply of a base station device or an on-board station device is switched from a normal power supply to an emergency power supply, the interval for transmitting a polling signal or a polling response signal is longer than usual. It has been disclosed.

Japanese Patent No. 6074260

In the event of a large-scale disaster, it will be necessary to limit the power required to operate the train as much as possible. However, in the base station device in the conventional FDMA radio system, there is a problem that the power consumption cannot be suppressed because the number of radios used cannot be reduced even when a large-scale disaster occurs.

The present invention has been made in view of the above-mentioned conventional circumstances, and provides a base station apparatus capable of reducing the number of radios used as necessary and suppressing power consumption. The purpose is.

In the present invention, in order to achieve the above object, the base station device and the wireless communication system are configured as follows.
(1) A base station device provided with a plurality of radios using different frequencies for wireless communication with the on-board station device mounted on the train, and a power supply unit is provided for each radio. In, two or more first radios that transmit voice data by the FDMA method, one second radio that transmits voice data by the SCPC method, a first mode for operating the first radio, and the above. operating the second radio, a second mode for cutting off the power of the first radio, and a control unit for controlling the switching of comprises any by one during the operation of the first mode or the second mode Regardless of the above, the FDMA control data and the SCPC control data are transmitted to the on-board station device, and the control unit uses the base station device for both the FDMA control data and the SCPC control data. By storing the mode information indicating whether the operation is performed in the first mode or the second mode, the on-board station device can be used as the voice data in the FDMA method when the base station device is in the first mode. It is characterized in that it is operated so as to perform transmission / reception, and when the base station apparatus is in the second mode, it is controlled to operate so as to perform transmission / reception of voice data by the SCPC method.

(2) In the base station apparatus according to (1) above, the control unit is characterized in that one of the first radios is operated as the second radio.

( 3 ) A radio that is equipped with a plurality of radios that use different frequencies and is provided with a power supply unit for each radio to perform wireless communication with the on-board station device mounted on the train. In the communication system, the base station apparatus includes a first mode in which at least two or more first radios that transmit voice data by the FDMA method are operated, and one second radio that transmits voice data by the SCPC method. It has at least switchable between a second mode of operating and shutting off the power of the first radio , and FDMA control data and FDMA control data regardless of whether the first mode or the second mode is operating. The SCPC system control data is transmitted to the on-board station device, and the base station device operates in either the first mode or the second mode for both the FDMA system control data and the SCPC system control data. The mode information indicating the inside is stored, and the on-board station device is based on the mode information stored in the FDMA system control data or the SCPC system control data received from the base station device. When the apparatus is in the first mode, audio data is transmitted / received by the FDMA method, and when the base station apparatus is in the second mode, audio data is transmitted / received by the SCPC method.

According to the present invention, it is possible to provide a base station apparatus capable of reducing the number of radios used as needed and suppressing power consumption.

It is a figure which shows the configuration example of the base station apparatus of the FDMA wireless system which concerns on 1st Embodiment of this invention. It is a figure which shows the format example of the broadcast channel (BCCH) used in the communication of the FDMA system. It is a figure which shows the format example of the control channel (CCH) used in the communication of SCPC system. It is a figure explaining the switching of the operation mode of a base station apparatus. It is a figure explaining the switching of the operation mode of a base station apparatus. It is a figure explaining the switching of the operation mode of a base station apparatus. It is a figure explaining the switching of the operation mode of a base station apparatus. It is a figure which shows the structural example of the base station apparatus of the FDMA wireless system which concerns on 2nd Embodiment of the apparatus of this invention.

An embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, for example, the base station apparatus according to the present invention includes a plurality of radios (21 to 25) that use different frequencies, and is provided with a power supply unit (12) for each radio. In the station equipment, a first mode (normal mode) in which at least two or more first radios (22, 23) for transmitting voice data by the FDMA method are operated, and a second mode in which the voice data is transmitted by the SCPC method. The control unit (20) is provided with a control unit (20) that controls switching from the second mode (power limitation mode) that operates the radio (24) at least, and the control unit (20) is the first radio in the second mode (power limitation mode). It is characterized by shutting off the power supply of the machine (22, 23). Hereinafter, the base station apparatus according to the present invention will be specifically described with reference to examples.

(First Example)
FIG. 1 shows a configuration example of a base station device of the FDMA wireless system according to the first embodiment. The base station apparatus of this example includes radios 21 to 23 that perform wireless communication using three channels (Cch / T1ch / T2ch) of the FDMA system, radios 24 that perform wireless communication of the SCPC system, and a spare. A radio device 25 for use is provided, and a control unit 20 for controlling these is provided. The radios 21 to 25 perform wireless communication with the on-board station device mounted on the train by using channels having different frequencies f1 to f4. That is, the base station apparatus of this example uses a total of four channels.

The radio 21 is assigned a frequency f1 and transmits / receives control data via an FDMA control channel (Cch). The radio 22 is assigned a frequency f2, and transmits / receives voice data through the first communication channel (T1ch) of the FDMA system. The radio 23 is assigned a frequency f3, and transmits / receives voice data through the second communication channel (T2ch) of the FDMA system. The radio 24 is assigned a frequency f4, and transmits / receives control data and voice data by the SCPC method. The radio 25 is a spare machine that operates in place of the radio when any of the radios 21 to 24 fails.

Each of the radios 21 to 25 includes a radio unit 11 for performing wireless communication using an assigned frequency, and a power supply unit 12 for supplying electric power to the radio unit 11.
The control unit 20 operates by the electric power supplied from an arbitrary power supply unit 11 among the power supply units 11 provided in each of the radios 21 to 25. The control unit 20 is composed of a plurality of (two in this example) control unit boards, and one of the control unit boards is a working board that is normally used, and the other board is a working board when the working board fails. It is a spare board used for such purposes.

The base station apparatus of this example has a normal mode and a power limiting mode.
In the normal mode, the radios 21 to 23 are operated to transmit the control data and the voice data by the FDMA method, and the radio 24 is operated to transmit the control data and the voice data by the SCPC method. The base station device in the normal mode can perform communication related to a voice call with a predetermined number (two in this example) of the on-board station devices by the FDMA method.
In the power limitation mode, the radio 21 is operated to transmit control data by the FDMA method, and the radio 24 is operated to transmit control data and voice data by the SCPC method. Further, in the power limit mode, the power supplies of the radios 22 and 23 are cut off. The base station device in the power limit mode can perform communication related to a voice call with a predetermined number (two in this example) of the on-board station devices by the SCPC method.
The control data includes mode information described later in addition to call system information and alarm information, and is always transmitted by both the FDMA method and the SCPC method, and is selected by the on-board station device.

The control unit 20 operates the base station device in the normal mode in normal times, and switches to the power limit mode in response to receiving a signal instructing the power limit from an external device or system. Further, when switching to the power limiting mode, the radios 22 and 23 are instructed to shut off the power supply. The power supply unit 12 of the radios 22 and 23 cuts off the power supply to the radio unit 11 in response to an instruction to cut off the power supply from the control unit 20.

In this way, the base station device of this example switches from the normal mode to the power limit mode in response to the instruction of the power limit, and accordingly, the power supply of the radio that is not required in the power limit mode is turned on. Cut off. Therefore, according to the base station device of this example, power is supplied to all the radios 21 to 25 in the normal state, but power can be controlled so as not to be supplied to the radios 22 and 23 when the power is limited. At the time of limitation, the base station device can be operated with 3/5 of the normal power (60% power). That is, it is possible to reduce the number of radios used as needed to reduce power consumption.

Further, the base station apparatus of this example uses the base station for the FDMA control data transmitted from the radio 21 and the SCPC control data transmitted from the radio 24 under the control of the control unit 20. By storing the mode information indicating whether the device is in the normal mode or the power limit mode, the operation mode of the base station device can be determined only by referring to the mode information in the control data in the on-board station device. It is configured.

FIG. 2 shows a format example of a broadcast channel (BCCH) used in FDMA communication. In this example, FDMA usage information is stored as mode information in a spare bit (8th bit in this example) in the third octet (channel information) of BCCH. The FDMA usage information in this example indicates that the SCPC method is being used (operating in the power limitation mode) when the bit value is on (1), and the FDMA method is used when the bit value is off (0). Indicates that it is in use (operating in normal mode).

FIG. 3 shows an example of the format of the control channel (CCH) used in the SCPC method communication. In this example, SCPC usage information is stored as mode information in a spare bit (fourth bit in this example) in octet 1 of the header portion of the CCH. The SCPC usage information in this example indicates that the FDMA method is being used (operating in normal mode) when the bit value is on (1), and the SCPC method is used when the bit value is off (0). Indicates that it is medium (operating in power limit mode).

The on-board station device receives at least one of the FDMA control data and the SCPC control data transmitted from the base station device, and refers to the mode information (FDMA usage information or SCPC usage information) stored in them. Therefore, it is determined whether the operation mode of the base station apparatus is the normal mode or the power limit mode. Then, when the base station apparatus is in the normal mode, it operates to transmit and receive voice data by the FDMA method, and when the base station apparatus is in the power limitation mode, it operates to transmit and receive audio data by the SCPC method.
As a result, even if the base station device in the normal mode and the base station device in the power limit mode are mixed along the route on which the train equipped with the on-board station device travels, the on-board station device continues the voice data. You will be able to send and receive.

Hereinafter, switching of the operation mode (normal mode / power limit mode) of the base station apparatus will be described with reference to FIGS. 4 to 7. It is assumed that there are base station devices 1 to 3 along the route on which the train travels, the base station devices 1 and 3 are operating in the normal mode, and the base station device 2 is operating in the power limiting mode. doing. The base station devices 1 and 3 in the normal mode can transmit and receive voice data by the FDMA method with the on-board station device of the train under the control (within the communication range). On the other hand, the base station device 2 in the power limit mode can send and receive voice data to and from the on-board station device of the train under its control by the SCPC method.

(State 1) Being under the control of the base station in the normal mode As shown in FIG. 4, it is assumed that the on-board station device is under the control of the base station device 1 operating in the normal mode. In this case, since the mode information in the FDMA control data transmitted from the base station device 1 indicates the normal mode, the on-board station device recognizes that the base station device 1 is operating in the normal mode. Then, it operates to send and receive voice data by the FDMA method.

(State 2) Start of a call under the control of a base station in normal mode As shown in FIG. 5, the on-board station device makes a voice call with another communication device such as a central device (ground control device) by the FDMA method. Suppose you have started. Even after the voice call is established, the on-board station device continues the call by the FDMA method while the line is under the control of the base station device 1.

(State 3) Handoff from the base station in the normal mode to the base station in the power limit mode As shown in FIG. 6, the power limit is performed while the on-board station device is making a voice call with another communication device by the FDMA method. It is assumed that the user has moved to the control of the base station device 2 operating in the mode. In this case, since the mode information in the control data of the FDMA system transmitted from the base station device 2 indicates the power limiting mode, the on-board station device switches to transmit and receive voice data by the SCPC system. Since the base station device 2 transmits / receives voice data by the SCPC method, the on-board station device can continuously transmit / receive voice data and can continue voice communication.

(State 4) Handoff from the base station in the power limit mode to the base station in the normal mode As shown in FIG. 7, the on-board station device is making a voice call with another communication device by the SCPC method, and the normal mode is used. It is assumed that the user has moved to the control of the base station device 3 in operation. In this case, since the mode information in the SCPC system control data transmitted from the base station device 3 indicates the normal mode, the on-board station device switches to transmit and receive voice data by the FDMA system. Since the base station device 3 transmits / receives voice data by the FDMA method, the on-board station device can continuously transmit / receive voice data and can continue voice communication.

As described above, the base station apparatus of this example transmits control data in both the FDMA system and the SCPC system in both the normal mode and the power limiting mode, and each of them is controlled by the control unit 20. The control data is configured to store mode information indicating whether the base station apparatus is in the normal mode or the power limit mode. Therefore, the on-board station apparatus can specify the operation mode of the base station apparatus only by referring to the mode information in the control data of either the FDMA system or the SCPC system. As a result, the on-board station device changes the FDMA method or the SCPC method as appropriate according to the switching of the operation mode of the base station device (or according to the movement of the base station device having a different operation mode to the umbrella). You can continue the voice call.

(Second Example)
In the first embodiment, the radios (22, 23) for transmitting and receiving voice data by the FDMA method and the radios (24) for transmitting and receiving control data and voice data by the SCPC method are independently provided. On the other hand, in the second embodiment, one of the radios that transmit and receive voice data by the FDMA method is operated as a radio that transmits and receives control data and voice data by the SCPC method in the power limitation mode. It is a thing.
In the following, the description of the portion overlapping with the first embodiment will be omitted as appropriate, and the portion peculiar to the second embodiment will be mainly described.

FIG. 8 shows a configuration example of the base station apparatus of the FDMA wireless system according to the second embodiment. The base station apparatus of this example includes radios 31 to 34 that perform wireless communication using four FDMA channels (Cch / T1ch / T2ch / T3ch), respectively, and a spare radio 35. A control unit 30 for controlling these is provided. Further, the radio unit 34 can also operate as an SCPC type radio unit according to an instruction from the control unit 30.

The control unit 30 operates the base station device in the normal mode in normal times, and switches to the power limit mode in response to receiving a signal instructing the power limit from an external device or system. Further, when switching to the power limiting mode, the radios 32 and 33 are instructed to shut off the power supply, and the radio 34 is instructed to operate as an SCPC type radio. The power supply unit 12 of the radios 32 and 33 cuts off the power supply to the radio unit 11 in response to the instruction to cut off the power supply from the control unit 30.

In this way, the base station device of this example switches from the normal mode to the power limit mode in response to the instruction of the power limit, and accordingly, the power supply of the radio that is not required in the power limit mode is turned on. Cut off. Further, one of the radios used for transmitting and receiving FDMA-type voice data is switched to operate as an SCPC-type radio. Therefore, according to the base station device of this example, power is supplied to all the radios 31 to 35 in the normal state, but power can be controlled so as not to be supplied to the radios 32 and 33 when the power is limited. At the time of limitation, the base station device can be operated with 3/5 of the normal power (60% power). That is, it is possible to reduce the number of radios used as needed to reduce power consumption.

In the second embodiment, when the base station apparatus returns from the power limitation mode to the normal mode (or when it is moved from the umbrella of the base station apparatus of the power limitation mode to the umbrella of the base station apparatus of the normal mode), the base Transmission of SCPC-type control data (and voice data) from the station equipment is interrupted. Therefore, the on-board station apparatus in the second embodiment may be automatically changed to the FDMA system when the data reception of the SCPC system fails. Alternatively, the control data of the FDMA system may be constantly monitored, and the operation mode of the base station apparatus may be specified based on the mode information in the control data of the FDMA system.

Here, the configurations of the system, the apparatus, and the like according to the present invention are not necessarily limited to those shown above, and various configurations may be used. For example, various extended examples and modified examples described above may be combined.
Further, the present invention can also be provided as a method or method for executing the process according to the present invention, a program for realizing such a method or method, a storage medium for storing the program, or the like.

INDUSTRIAL APPLICABILITY The present invention can be used for a wireless communication system including a base station device that performs wireless communication with an on-board station device mounted on a train.

11: Radio unit, 12: Power supply unit, 20, 30: Control unit, 21-25, 31-35: Radio unit

Claims (3)

In a base station device provided with a plurality of radios using different frequencies for wireless communication with an on-board station device mounted on a train and a power supply unit provided for each radio.
Two or more first radios that transmit audio data in FDMA format,
One second radio that transmits audio data by SCPC method,
A first mode for operating the first radio, a second radio to operate the control unit for controlling the second mode to cut off the power of the first radio, the switching of,
Equipped with
Regardless of whether the operation is in the first mode or the second mode, the FDMA control data and the SCPC control data are transmitted to the on-board station device.
The control unit stores, in both the FDMA control data and the SCPC control data, mode information indicating whether the base station apparatus is operating in the first mode or the second mode. The on-board station device is operated so as to transmit and receive voice data by the FDMA method when the base station device is in the first mode, and when the base station device is in the second mode, the voice data is transmitted by the SCPC method. A base station device characterized in that it is controlled to operate so as to transmit and receive. In the base station apparatus according to claim 1,
The control unit is a base station apparatus characterized in that one of the first radios is operated as the second radio. In a wireless communication system in which a base station device provided with a power supply unit for each radio device and having a plurality of radio devices using different frequencies communicates wirelessly with an on-board station device mounted on a train. ,
The base station apparatus operates at least a first mode in which two or more first radios that transmit voice data by the FDMA method are operated, and at least one second radio that transmits voice data by the SCPC method. It has a second mode that shuts off the power of the first radio, and it has FDMA control data and SCPC control regardless of whether it is operating in the first mode or the second mode. The data is transmitted to the on-board station device,
Both control data of the control data and the SCPC method FDMA scheme, mode information indicating one by one during the operation of the base station apparatus of the first mode or the second mode is stored,
The on-board station device uses the FDMA method when the base station device is in the first mode based on the mode information stored in the FDMA control data or the SCPC control data received from the base station device. A wireless communication system characterized in that voice data is transmitted and received, and when the base station apparatus is in the second mode, voice data is transmitted and received by the SCPC method.

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