JPH047138B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field to which the Invention Pertains] The present invention relates to taxi radio and other mobile radio systems in which several groups (several companies) jointly use the same channel, and one group The present invention relates to a mobile radio system configured such that when one communication channel is being used, other groups cannot use this communication channel.

[Background of the invention]

Conventionally, in this type of mobile radio system, base stations and mobile stations in each group communicate via a control station, and each mobile station waits on a downlink control channel from the control station and receives the designation of an idle channel number. Then, the designated group of mobile stations and base stations conduct a call via this designated uplink and downlink communication channel. During this time, stations in other groups are prohibited from using this communication channel.

Since the number of channels allocated to this type of mobile radio system is smaller than the number of groups, if a call is made that exceeds the communication capacity, priority is given to first-come-first-served calls.
Therefore, if one group's call time is long, other groups will have to wait for a long time, and fair communication will not be possible. For this reason, we set a limit on the time that one group can use one call channel continuously, and when this time arrives, the control station automatically sends a control signal and the call channel can be used until then. The group that was currently in use will be forcibly moved to standby status.

In such a system, in order to conduct effective communication with less waste, each station must know the usage status of the call channel, and during a call, be aware of the remaining time that its own group can use the call channel. It is desirable to be able to do so.

[Purpose of the invention]

The present invention was made against this background, and an object of the present invention is to provide a method in which each base station or mobile station can recognize the state of communication channel control and can effectively utilize frequencies. shall be.

[Summary of the invention]

In the present invention, a plurality of communication channels are shared by a plurality of groups of base stations and/or mobile stations under the control of one or more control stations, and the base stations and mobile stations stand by on the control channel and use the control channel. In a mobile radio communication system configured to receive a designated communication channel and perform communication between a group of base stations and mobile stations on this communication channel, a signal transmitted from the control station includes:
The present invention is characterized in that it includes at least information on the usage status of each communication channel, and includes means for optically displaying this information on at least some of the base station and mobile station. Furthermore, it is preferable that the signal transmitted from the control station include information on the remaining call time, and that at least some of the base station and mobile station include means for optically displaying this information.

[Explanation of Examples]

FIG. 1 is a conceptual diagram showing an example of the configuration of the system of the present invention. In FIG. 1, 1 is a control station, which is installed, for example, in a high place near the center of a city. Reference numeral 2 denotes a base station, which is, for example, the headquarters of each taxi company, and is shared by several companies to utilize this system.
3 is a mobile station, and each mobile station 3 belongs to one of the base stations 2, that is, to one of the companies. Here, one company is represented as one group.

In this system, one control channel for each uplink and downlink, and several communication channels, each consisting of uplink and downlink, are allocated. For example, the number of groups is 10
Then, there are three sets of communication channels. The base station 2 and mobile station 3 devices can transmit to each uplink channel and receive each downlink channel out of this one set of control channels and three sets of communication channels. The control station 1 receives the upstream channel of the control channel and the communication channel, and transmits it to the downstream channel. Furthermore, the control station 1 is equipped with a booster, and is equipped with a device that amplifies the signal received on the upstream channel of the communication channel and broadcasts it on the downstream channel.

With such a configuration, each base station 2 and mobile station 3
is in a standby state receiving downstream signals from the control channel when not making a call. Now, when one mobile station 3 makes a call, it automatically transmits its own code consisting of a pulse train on the uplink of the control channel, and when this is received and identified by the control station 1, it transmits a pulse train on the downlink of the control channel. The first communication channel is designated for all mobile stations 3 and base stations 2 in the group to which the calling mobile station 3 belongs. Each mobile station 3 and base station 2 that received this
When it is determined that the designation is for the own group, the transmission and reception frequencies are automatically switched to the first communication channel all at once. Mobile stations 3 and base stations 2 other than that group are left in a standby state where they continue to receive downlinks on the control channel.

Each station in the group that has moved to the first talking channel is free to transmit to its upstream channel. Since it is amplified by the control station 1 and broadcast down the first communication channel, its contents can be received. When this first communication channel is not used for several seconds consecutively, or when a predetermined exclusive time has elapsed, a control signal is broadcast from the control station 1 to the downlink of the first communication channel, and each mobile station 3 and base station 2, the transmitting and receiving frequencies are switched all at once and the channel returns to the control channel.

Here, the feature of the system of the present invention is that the control signal transmitted from the control station 1 includes information necessary for control as well as the usage status of each communication channel and whether the communication channel is exclusive. This is appropriately displayed on each base station 2 and mobile station 3, including information such as the remaining time available, so that each station can recognize the status of the entire system.

FIG. 2 is a diagram showing the format of the control signal sent to the control channel. This control signal is an FSK signal at a rate of 1200 bit/sec. The control signal is a specification consisting of 3 synchronization bits 5, 11 channel bits ₇₁ to _7n each provided according to the communication channel separated by an inter-bit interval 6 of 2 bits, and 80 bits. Consists of 8 bits.

With this configuration, each channel bit 7 ₁ ~
7 The first bit of _n indicates whether the channel is free or in use. The next 6 bits display the number of the group using that channel.
The next 4 bits display the remaining time allowed for exclusive use of the call for that group in minutes. Further, in designation bit 8, the number of an empty communication channel corresponding to the next call is designated using 4 bits. If there are no free channels, all of these 4 bits will be "0". If all 4 bits specifying a free channel are "0", the next 5th bit changes from "0" to "1", indicating that there is no free channel and reservations are being accepted, and the 5th bit from the 6th bit indicates that the reservation is being accepted. Display time in seconds. From the 11th bit, 7 bits each transmit the station numbers for 10 stations for which reserved calls have been accepted.

The base station 2 and mobile station 3 of each group receive the control signal on the downlink control channel, and the status of each channel is displayed based on this information. That is, the usage status of each communication channel is displayed by lighting a light emitting diode corresponding to each communication channel in blue. When all call channels are displayed as being in use, the other light emitting diodes will light up yellow, indicating that reservation communication is being accepted. When the reserved communication reception area becomes full, the other light emitting diodes light up in red, indicating that the reservation communication reception has been stopped.

Further, when one mobile station 3 specifies the call channel in use and makes an inquiry on the uplink control channel, the number of the group using the call channel is displayed. Further, if the mobile station 3 makes a call while the yellow light is on, it becomes a reserved communication and the reserved waiting time is displayed. This reservation time is subject to change depending on traffic conditions. Since no reservation communication is accepted while the red light is on, even if the mobile station 3 picks up, no call is made and an alarm is displayed (for example, an alarm sound). Further, when the mobile station 3 cancels the reserved communication, the reserved time display goes out. Further, the number of the mobile station 3 is deleted from the station number for which the reserved call has been accepted in the designation bit 8 of the control signal, and the acceptance order is moved up one by one. In addition, the remaining time of the call is displayed on the mobile station during the call by a clock-down timer.

[Explanation of effects]

As explained above, according to the present invention, various information on all communication channels is transmitted to each base station and mobile station, and the base station or mobile station receives and displays this information.

Therefore, each base station and mobile station can communicate efficiently while recognizing the overall situation, so it is possible to provide a mobile radio system that can effectively utilize frequencies.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of main parts of an embodiment of the present invention. FIG. 2 is a diagram showing a signal format of a control signal. 1...Base station, 2...Antenna, _31-3o ...Mobile _station , 5...Synchronization bit, 6...Bit interval, _{71-7n ...} Channel bit, 8...
Specified bit.

Claims (1)

[Claims] 1 A plurality of communication channels are shared by a plurality of groups of base stations and/or mobile stations under the control of one or more control stations, and the base stations and mobile stations stand by on the control channel and use the control channel to control the communication channels. In a mobile radio communication system configured to carry out calls between a base station and a mobile station in one group using a designated communication channel, the signal transmitted from the control station includes at least information on the usage status of each communication channel. 1. A mobile radio communication system comprising means for optically displaying this information on at least some of the base station and mobile station.