JP2803640B2 - Group communication channel allocation method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a group communication channel allocation method in a cellular mobile communication system.

[0002]

2. Description of the Related Art As this type of group communication system conventionally used, the system shown in FIG. 8 is generally employed. FIG. 8 shows a communication sequence of a polling communication system which is a conventional group communication system disclosed in Japanese Patent Application Laid-Open No. 3-232337. That is, in the conventional group communication method, polling and selecting are combined to collect messages from terminals in the same terminal group sequentially by polling, and if there is a message to be communicated from the center side, the polling designation is made. In this method, the terminal was selected at the right time and the message was sent.

[0003] Also, priority / non-priority levels are provided for the contents of messages, and transmission / reception of priority messages is performed within the time limit of polling time for all terminals. This is a method of performing polling control so as to transmit and receive data.

Further, when there are a plurality of group communication terminal groups at the same time, a method is adopted in which each group is sequentially polled and selected.

[0005]

The above-mentioned prior art has the following problems.

A first problem is that, in the prior art, when performing group communication and performing telegram communication by sequentially performing polling designation to a plurality of terminals by polling control in a center apparatus, the terminal side issues an emergency. If you want to make a transmission request, you need to wait until the polling specification is reached. The reason for this is that if polling is not specified on the same frequency, communication between the other terminal and the center apparatus is hindered.

[0007] The second problem is that, in a system with high communication traffic such as performing dynamic management while performing business communication, in the polling / selecting communication, if the number of terminals increases, the polling interval increases. If the communication information speed for business use is not taken into consideration, the interval of collecting the position information becomes long, and the freshness of information that requires real-time properties such as position information decreases.

In the group communication system, by devising the assignment of communication channels, the speed of communication and the real-time property in each group communication group are improved.

In view of the above-mentioned problems of the prior art, it is an object of the present invention to provide a group communication channel allocation method capable of performing emergency communication requests from terminals, dynamic position management, and high traffic communication.

[0010]

SUMMARY OF THE INVENTION The group communication channel allocation method of the present invention uses a TDMA / FDD (Time Di
vision MultipleAccess / Fre
A cellular communication system comprising a plurality of terminals, a plurality of radio base stations, a base station control device, and a center system device having a radio communication function of a quenching division duplex (time division multiple access / frequency division bidirectional transmission) system, In a mode in which the communication mode between the center apparatus and the terminal is centered on the group and the individual communication scheme, the assignment of the radio channel between the terminal and the radio base station is performed as a set of the broadcast channel and the communication channel.

When terminals belonging to the same group are distributed in a plurality of radio zones, each radio base station transmits one broadcast channel and one communication channel to the same group terminal.
Wireless channels may be assigned as a set.

When the traffic in the group communication becomes large, the assignment of the radio channel may be performed by setting a broadcast channel and a plurality of communication channels as one set.

Further, during group communication, distribution of broadcast data to all terminals and designation of polling to each communication group are performed by broadcast channel downlink, and each terminal uses the uplink of the communication channel to designate polling from each terminal. The response information may be collected, and the group command message and the individual command message may be simultaneously communicated to the terminal using each communication channel downlink.

[0014] Also, a communication request is made from a terminal in group communication using the allocated broadcast channel uplink,
The radio base station may change the polling designation based on the broadcast channel downlink to the terminal, receive a message from the terminal using the communication channel uplink, and relay the message to the center apparatus.

In the allocation of the communication channels by the TDMA system in the configuration of the group communication system in the mobile communication system, the channel allocation system of the group communication of the present invention is a system for simultaneously allocating a broadcast channel and a communication channel.

More specifically, each radio frequency is time-divided into a plurality of channels, one of which is a broadcast channel, and the other is a communication channel.

[0017] Further, a control channel is further allocated to one of the time-divided channels to at least one of the plurality of radio frequencies owned by each radio base station.

Further, the logical channel structure of the broadcast channel includes synchronization information, polling designation information, broadcast data, and additional information for wireless section transmission.

The broadcast channel transmits the polling designation and the broadcast data to individually designate the terminals of the group.
The unique information of the terminal can be collected. At the same time, broadcast data can be transmitted to all terminals.

Each terminal makes a transmission request in real time using the uplink of the broadcast channel, and can transmit a message from the terminal to the center system using the uplink of the communication channel.

By simultaneously allocating a plurality of communication channels, the information transmission speed between the group or individual terminals and the center can be increased.

[0022]

Next, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic system configuration diagram of an embodiment of the present invention.

Referring to FIG. 1, in an embodiment of the present invention, a base station controller 1, a base station controller 2 for managing a plurality of radio zones 51 to 5n and radio base stations 31 to 3n, and a radio communication system in each radio zone. each terminal group 4a moving around in _1-7, 4
b ₁ to ₈ and 4c ₁ to ₅ are present. Each radio base station is located at a distance where radio waves f _{1 to} f ₉ of the 4-channel TDMA / FDD system are several waves and interference between radio zones does not easily occur. And
Are located.

The center system device 1 includes a dynamic display device 11 for displaying the current position of each terminal in real time, and a GP mounted on each terminal for constantly collecting the position information.
S (Global Positioning System)
em, satellite navigation) to manage the distribution of GPS position correction information for correcting data and the function of organizing the corrected position information, and to manage the unique information (ID, subordinate group, etc.) of each terminal. Communication device 1 that communicates with the subscriber management device 13 to be activated for each group
4 to 1 m.

FIG. 2 is an arrangement diagram of each channel on a 4-channel TDMA / FDD.

As shown in FIG. 2, a 4-channel TDMA /
The arrangement of each channel on the FDD is as follows when radio waves are allocated to each radio base station by several waves.

A control channel (control CH or C-CH) C is assigned to one of the time-divided channels for at least one of the plurality of radio frequencies owned by each radio base station.

Radio frequencies f ₁ and f ₃ including the control channel C
Is a broadcast channel (broadcast CH or PC
H) P, control channel C, communication channel (communication CH or TCH) T, and radio frequency f ₈ not including control channel C is composed of broadcast channel P and communication channel T for each frame.

The broadcast channel P includes additional information R for radio section transmission, synchronization information S for frame / multiframe synchronization, and communication channels T _{1 to} T on the radio frequency.
₃ (or T ₂ , T ₃ ) corresponding polling designation information P _{1 to} P ₃
And broadcast data AD such as GPS position correction information and system common information to be commonly broadcast to all terminals on the system.
And communication data TD such as a communication message, a terminal group ID, and a terminal ID.

The control channel C comprises the above-mentioned additional information R for wireless section transmission and control data CD such as a control message, a terminal group ID, and a terminal ID.

Next, referring to FIG. 3 to FIG.
The operation of the embodiment will be described. First, FIG.
FIG. 4 shows a group communication / broadcast communication sequence.
FIG. 7 is a diagram showing channel designation and reception channel operation during transmission.
You. As shown in FIG.
Step 4a₁~ 4a₇Sends a communication request message to group a of
The subscriber management device 13 adds the ID of the group a, and
It is transmitted to the local station controller 2. The base station control device 2
Relay to base stations 3l to 3n and control channel C on base station
Call each terminal of terminal group a using group a
Make a call by telegram. Each terminal 4a₁~ 4a₇Is the response
The message is transmitted using the control channel C. At the same time,
The base stations 3l to 3n that received the answer indicate the vacant radio frequency and the
Select idle communication, channel T and execute channel designation
You. As shown in FIG. ₁Is the control channel C
From the channel designation information received at₁Specify
Communication channel, T_TwoTransfer the receiving channel to
Its frequency f₁Start receiving the above broadcast channel P
You.

The terminal 4a ₂ similarly shifts to a state of receiving the broadcast channel P and the communication channel T ₂ of the radio frequency f ₁ .

[0034] If all the terminals 4a ₁ to 4A ₇ is shifted to a group communication, communication console device 14 transmits the group a communication start message to the dynamic state management unit 12, and requests the dynamic monitoring. The movement management device 12 transmits a GPS position correction information message and starts monitoring movement. The GPS position correction information is distributed to the terminals of the group a by the broadcast channel P, and each of the radio base stations 31 to 3n controls the polling designation information on the broadcast channel P for the terminals of the group a. Then, the location information is collected using the communication channel T,
Notify the dynamic management device 12.

Furthermore, communication console device 14 when transmitting the group a command telegram to each terminal 4a ₁ to 4A ₇ in the group communication, via a respective radio base station 3l~3n from the base station controller 2, Simultaneous distribution is performed using the communication channel T.

When transmitting a unique message to the designated terminal 4a ₃ of the group a, the base station controller 2 communicates using the communication channel T ₃ of the radio frequency f ₃ via the radio base station 32. I do.

Next, the individual communication request sequence during the broadcast communication will be described with reference to FIG. Each radio base station to the terminal 4b ₁ ~4b ₈ group b, using a communication channel and broadcast channel on a radio frequency specified channel to collect location information performs polling control for each radio zone when and if the terminal 4b ₄ transmits a message to the communication console device 1m, the terminal 4b ₄ increases the communication request message in an uplink channel of the broadcast channel P. The radio base station 32 receives the communication request message, to change the polling value specified broadcast channel P to 4b _4, receives a communication message from the uplink channel of the communication channel T from the terminal 4b _4, communication console device 1
m and relay the communication message to m. The radio base station 32, after receiving the communication message again resumes collection of location information is returned polling designated value of the broadcast channel P to 4b _3.

FIG. 6 is a diagram for comprehensively explaining the transmission / reception operation of the broadcast channel and the communication channel at the time of group communication according to the embodiment of the present invention. GPS by in broadcast channel to the designated state of the communication channel with the radio frequency on each radio zone 5l~5n to the terminal group 4a ₁ to 4A ₉
Distribution of position correction information and change of polling designation information, and
A group a command telegram delivery, a command message notification to the specified terminal 4a _3, illustrates the channel usage for communication request from the terminal 4a _7. Each operation is as described above. It should be noted that the communication message can be communicated over a plurality of frames.

FIG. 7 is a diagram showing the assignment of a plurality of communication channels. As shown in Figure 7, when the communication console device 14~1m need is, via the base station controller 2 to the radio base station 3L～3n, it was assigned a plurality of communication channels T _2, T ₃ at the same time by assigning on the radio frequency f _1,
It is possible to communicate telegrams with a large amount of information at twice the information speed.

As described in the description of the operation of the embodiment of the present invention, by assigning two channels to each terminal at the same time by using the TDMA wireless communication method in the group communication that occupies most of the business communication, the dynamic state of the terminal is determined. It is possible to simultaneously execute the management of the position information, the business communication, and the instruction. Furthermore, communication of only an individual terminal and communication to a plurality of groups are also possible as the application. Also, by executing a communication request from a terminal on the uplink of the broadcast channel P,
Communication can be requested to the communication console without waiting for selecting by polling, and an urgent report can be performed.

[0041]

As described above, according to the present invention, a broadcast channel for polling and a communication channel for business are simultaneously assigned to the group communication channel assigned to each terminal. There is an effect that transmission request can be made when necessary. Thus, emergency communication can be performed in real time.

A second effect is that a plurality of communication channels can be assigned at the same time, and thus the communication information speed for business can be set to a variable rate. As a result, a large amount of communication information can be maintained.

A third effect is that since the broadcast channel is arranged in all radio frequencies, common system information and GPS position correction information can be simultaneously delivered to terminals in all groups. Thereby, control of the whole system becomes possible.

[Brief description of the drawings]

FIG. 1 is a schematic system configuration diagram according to an embodiment of the present invention.

FIG. 2 is a layout diagram of each channel on a 4-channel TDMA / FDD.

FIG. 3 is a group connection / broadcast communication sequence.

FIG. 4 is a diagram showing channel designation and reception channel operation during group communication.

FIG. 5 is an individual communication request sequence during broadcast communication.

FIG. 6 is a diagram comprehensively explaining the transmission / reception operation of a broadcast channel and a communication channel during group communication according to the embodiment of the present invention.

FIG. 7 is a diagram showing assignment of a plurality of communication channels.

FIG. 8 is a communication sequence of a polling communication system which is a conventional group communication method.

[Explanation of symbols]

1 of the center system apparatus 2 the base station controller 11 dynamic display device 12 dynamic management device 13 subscriber management device 14~1m communication console device 3l~3n radio base station 4a ₁ to 4A ₇ group a terminal 4b ₁ ~4b ₈ group b terminal 5l~5n wireless zone f ₁ ~ ₉ radio frequency of the terminal 4c ₁ ~4c ₅ group c

Claims (5)

(57) [Claims] 1. A cellular communication system comprising a plurality of terminals having a TDMA / FDD wireless communication function, a plurality of wireless base stations, a base station control device, and a center device, wherein the center device and the terminal are provided. A communication mode between the terminal and the radio base station, wherein the assignment of the radio channel between the terminal and the radio base station is performed as a set of a broadcast channel and a communication channel. Channel placement method. 2. The group communication channel allocation method according to claim 1, wherein when the terminals belonging to the same group are dispersed in a plurality of wireless zones, each of the wireless base stations transmits a broadcast channel to the same group terminal. A group communication channel allocation method, wherein a wireless channel is assigned as a set of communication channels. 3. The group communication channel allocation method according to claim 2, wherein, when the communication volume in the group communication becomes large, the radio channel is assigned as a set of a broadcast channel and a plurality of communication channels. Group communication channel allocation method to be used. 4. A group communication channel allocation method according to claim 2, wherein during group communication, broadcast data is distributed to all terminals by broadcast channel downlink and polling designation to each communication group is performed. From each terminal, while collecting response information at the time of specifying polling by using the communication channel uplink, and simultaneously communicating the group command message and the individual command message to the terminal using each communication channel downlink, Group communication channel allocation method to be used. 5. The group communication channel allocation method according to claim 4, wherein a terminal performing group communication issues a communication request using an allocated broadcast channel uplink, and the radio base station comprises:
A group communication channel allocation method, wherein a polling designation by a broadcast channel downlink is changed to the terminal, a message from the terminal is received using a communication channel uplink, and relayed to a center apparatus.