JPH08186867A - Multi-rate mobile radio communication system - Google Patents

Abstract

PURPOSE: To improve the reliability by adopting configuration of revising adpatively a transmission rate set to each channel for a transmitter-receiver so as to allocate efficiently the transmission rate of the channel thereby reducing number of rate class setting signals sent through the transmission line between a base station controller and a in-base station transmitter-receiver. CONSTITUTION: A transmitter-receiver 5 is installed in a base station 1 and six slots in time division are provided for one carrier, and a transmission rate is set for each slot. A base station controller 7 in a control station 6 sends/ receives a control signal to/from the transmitter-receiver 5 via an inter-station transmission line 8 to execute setting, maintenance, changeover and interruption of a radio channel. Through the constitution above, when a traffic of a call at a transmission rate exceeds a line capacity of the same transmission rate set for the transmitter-receiver 5, the base station controller 7 revises the channel of other rate class because no object for selected channel is available to avoid a call loss.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multirate mobile radio communication system characterized by transmission rate setting and line allocation.

[0002]

2. Description of the Related Art In a conventional digital mobile communication system, since there is a single rate type, there is no concept of rate type setting signal. Therefore, the line management in the base station controller does not consider the rate type. When assigning a line in a multirate system by the line management method in the conventional base station controller, when the request for the line used for communication occurs, the transmission rate capability of the mobile station is recognized and the rate type setting signal for each call Is transmitted from the base station control device to the intra-base station transmitting / receiving device, and after the transmission rate of the line in the carrier used in the transmitting / receiving device is set, line allocation is performed.

[0003]

At this time, in the transmission line between the base station control device and the transmission / reception device in the base station, the transmission rate used by the line in the base station control device due to a transmission error or the like and the line in the transmission / reception device in the base station. There is a high possibility that the state of the used transmission rate will fall into a mismatch.

In order to solve the above-mentioned problems, the present invention provides
The purpose is to efficiently allocate the transmission rate of the line and reduce the rate type setting signal transmitted on the transmission path between the base station control device and the intra-base station transmission / reception device to improve reliability.

[0005]

In order to solve the above-mentioned problems, the invention according to claim 1 has a base station and a control station for controlling the base station. Multiple lines can be used within one carrier,
In a multi-rate mobile radio communication system capable of transmitting and receiving information between a mobile station and a base station at a plurality of transmission rates, the transmission / reception device can adaptively change the transmission rate set for each line. Is characterized by.

According to the invention of claim 2,
The control means according to claim 1, wherein the control station determines whether or not there is a vacant line according to the transmission rate capability of the mobile station that has made the call request, and Select the free line and assign the line,
When the determination is that there is no idle line, a rate type setting change signal is transmitted to the transmission / reception device, and the transmission / reception device is set to a rate type different from the transmission rate of the mobile station that made the call request. And changing the transmission rate of the idle line to the transmission rate of the mobile station and allocating the line to the changed line.

According to a third aspect of the present invention, in the first or second aspect, the transmission / reception device maintains the transmission rate of the line used for the communication after the mobile station completes the communication.

[0008]

If the traffic of a call of a certain transmission rate exceeds the line capacity of the same transmission rate set in the transmitter / receiver, and if the rate type of each line is fixedly set, there will be a call loss. However, in the inventions of claims 1 and 2, since the base station control device does not have a candidate for the line to be selected, the line of another rate type is changed and the call is lost. Can be avoided.

Further, when lines with a high transmission rate and lines with a low transmission rate coexist, it becomes possible to allocate the lines efficiently.

According to the third aspect of the invention, the transmission / reception apparatus maintains the transmission rate of the line after the communication is completed, so that the rate type transmitted on the transmission line between the control station and the transmission / reception apparatus in the base station. The number of setting signals is reduced, and it is less likely that the transmission rate of the line used by the base station controller and the transmission rate of the line used by the transmitter / receiver in the base station will be inconsistent due to a transmission error or the like, and the reliability is improved.

[0011]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a multi-rate mobile radio communication system. In the base station 1, the service area 4 is formed by the radio waves transmitted and received between the antenna 2 on the base station 1 and the mobile stations 3A and 3B.
A and 3B communicate within the area 4. A transmitter / receiver 5 is installed in the base station 1, and 6 slots are prepared per carrier in a time division manner, and a transmission rate can be set for each slot.

The base station control device 7 in the control station 6 transmits / receives data to / from the transmission / reception device 5 in the base station 1 via the inter-station transmission line 8.
By transmitting and receiving control signals, the setting, maintenance, switching and disconnection of wireless lines are performed. The exchange 9 in the control station 6 is connected to the base station controller 7 and the public network 10 and has a circuit switching function.

FIG. 2 shows the slot arrangement within one carrier by the time division multiplexing method. 40 ms (sec) for one carrier
One frame is repeated and one frame is divided into six slots. The individual slots are assigned according to the transmission rate of the line.

FIG. 3 shows a slot allocation method within one frame. Full-rate lines occupy two slots per line within one frame (see (a) in the figure), and half-rate lines occupy one slot per line within one frame (( See b)). Also, PDC
Due to the restrictions on (Japanese standard), in a full rate line, a certain slot and a slot three slots after it must be assigned as a pair (see (a) in the figure).

Therefore, in the present system in which a full rate line and a half rate line are mixed in one carrier, in order to allocate slots efficiently, when only one of the paired slots is used as the half rate line, the other is used. Slot must be preferentially assigned to the half rate. For example, if slot # 1 has already been assigned to the half rate line, slot # 4 must be preferentially assigned if the next half rate line is requested (see (c) in the figure).

FIG. 4 is a diagram regarding rate types of mobile stations. In the mobile station, there are a full-rate dedicated station 3A and a half-rate dedicated station 3B, and the control channel transmits and receives control signals at full rate. The communication channel can communicate only at a rate dedicated to each mobile station.

FIG. 5 shows a configuration for controlling the line allocation of the base station controller. The base station control device has interfaces 7A and 7B and a CPU 7C, and the interface 7A is connected to a transmitting / receiving device in the base station.
Is connected to the upper exchange.

The CPU 7C comprises a ROM 71C storing a control program (including that shown in FIG. 10) and a RAM 72C having a work area. Using these, a control algorithm for setting, maintaining, switching and disconnecting a wireless line is provided. To execute.

Further, the CPU 7C manages an empty line for selecting a line for each rate type, and a full rate empty line management table and a half rate empty line management table exist in the RAM 72C.

FIG. 6 shows a configuration of a control channel and a communication channel in a wired section. The control channel is connected from the transmitter / receiver 5 to the exchange 9 via the base station controller 7. The communication channel is from the transmitter / receiver 5 to the exchange 9
Is directly connected to. When there is a request for communication from the mobile station via the control channel, after the wireless line is selected in the base station controller, the communication line is set and communication becomes possible.

Specifically, the mobile station reports the capability (rate type) of the mobile station, selects a line corresponding to the capability from the free line management table for each rate type in the base station control device, and By notifying the exchange of the line number, the communication line is set and the communication becomes possible.

A concrete embodiment will be described with reference to FIGS. 7 to 10 (FIG. 10 is a flow chart).

FIG. 7 shows an example of the rate type initial state when the system is started up. Two carriers are installed in the transmission / reception device in the base station, and the initial setting state of the transmission rate in each carrier is stored in the RAM in the base station control device as shown in FIG.

After the initial setting (S1 in FIG. 10), when a call request is generated (S2 in FIG. 10), the base station control device
A free line having a transmission rate corresponding to the capability of the mobile station is selected from the free line management table and assigned to the transmitting / receiving device for communication.

In the present embodiment, the free line management table at system startup is C at full rate.
It is assumed that H # 0, 2, 6, and 8 are set as idle lines, and that CH # 1, 4, 7, and 10 are set as idle lines at the half rate.

Here, the slot # 0 of the first carrier is changed to the channel # 0, and the slot #m of the nth carrier is set to the channel # {6 (n-1) + m}. According to this information, the rate type in the transmitter / receiver at startup is set, and the rate is set for each slot as shown in FIG.

When a full rate call request occurs, C
Select H # 0 from the full rate free line management table,
A communication CH activation request for CH # 0 is transmitted to the transmission / reception device (S3, S4, S5).

The transmission / reception device which has received the signal performs communication at the full rate in the pair of slots # 0 and # 3 (S
6).

When a half-rate call request occurs,
CH # 1 is selected from the half rate idle channel management table, and a communication CH activation request for CH # 1 is transmitted to the transmitting / receiving device (S3, S7, S8). The transmission / reception device that has received the signal performs communication at half rate in slot # 1 (S9).

In each case (S5, S6, S8, S
9) The selected channel is deleted from the free line management table. When communication is completed for each channel,
In the transmitter / receiver, the set rate is not changed, and the channel number is managed and registered again in the free line management table of the selected rate (S10, S1).
1, S12, S13).

FIGS. 8 and 9 show a slot allocation method in the case where there is no allocable half-rate vacant line in the half-rate vacant line management table in the base station controller (NO in S7). In FIG. 8, when there is no free line in the half rate free line management table and there is a free line in the full rate free line management table and there is a communication request from the half rate dedicated mobile station, In the station control device, CH # 0 on the full rate idle channel management table is selected and the setting is changed to CH # 0 and CH # 3 in the half rate idle channel management table (S14).

Next, a rate type setting change signal is sent to the transmitting / receiving device via the transmission line. In the rate type setting change signal, the address of the transmission / reception device to which this signal should be transmitted and the transmission rate to be set are set (S
15). Then, CH # 0 is selected from the half rate idle channel management table, and a communication CH activation request for CH # 0 is transmitted to the transmitting / receiving device (S8).

The transmission / reception device that has received the signal performs communication at half rate in slot # 0 (S9). Figure 9
Is a correspondence relationship between slots and channels in the transmission / reception device before and after receiving the rate type setting change signal. Prior to receiving the signal, slots # 0 and # 3 of the first carrier are set to full-rate channel # 0.

When the signal is received, slots # 0 and # 3 of the first carrier are set to half rate channels # 0 and # 3, respectively. The information of the signal is set as “channel # 0, half rate”, and from the correspondence between the channel number and the slot, “slot # 0 of the first carrier is set”.
And set slot # 3 to half rate ”. Even when the rate setting is changed, the transmission rate at the time when communication is completed is maintained for each channel.

The slot allocation method in the case where there is no assignable full-rate free line in the full-rate free line management table (NO in S4) can be executed according to the above (S16, S17).

According to the above method, the rate type setting change signal is transmitted on the transmission path between the base station controller and the transmitter / receiver in the base station only when there is no line in the free line management table in the base station controller. become.

Therefore, according to the present invention, the transmission rate of the line can be efficiently allocated, and conventionally, in the transmission line between the base station control device and the transmission / reception device in the base station, a transmission error or the like causes a base station control device. There was a high possibility that the state of the transmission rate of the line used by the transmission line in the base station and the state of the transmission rate of the line used by the transmission / reception device in the base station would fall into a disagreement. It is possible to reduce the number of rate type setting signals transmitted and improve reliability.

[0039]

When the traffic of a call of a certain transmission rate exceeds the line capacity of the same transmission rate set in the transmitter / receiver, if the rate type of each line is fixedly set, the call In the inventions of claims 1 and 2, the control station does not have a candidate for the line to be selected, so the line of another rate type is changed and the call is lost. Can be avoided.

Further, when lines with a high transmission rate and lines with a low transmission rate coexist, the lines can be efficiently allocated.

According to the third aspect of the invention, the transmission / reception device maintains the transmission rate of the line after the communication is completed, so that the rate type setting signal transmitted between the control station and the transmission / reception device in the base station is transmitted. The transmission rate used by the line in the base station controller due to reduced transmission errors,
It is less likely that the states of the transmission rates used by the lines in the control station will be inconsistent, and the reliability is improved.

As described above, according to the present invention, the rate type setting signal transmitted on the transmission path between the control station and the transmitting / receiving device in the base station is reduced to improve reliability, and the transmission rate of the line is increased. Can be allocated efficiently.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a multi-rate mobile radio communication system.

FIG. 2 is a diagram showing a slot arrangement in one carrier by a time division multiplexing method.

FIG. 3 is an explanatory diagram of a slot allocation method within one frame.

FIG. 4 is an explanatory diagram of rate types of mobile stations.

FIG. 5 is a configuration diagram of a base station control device.

FIG. 6 is a diagram showing a configuration of a communication / control line in a priority section.

FIG. 7 is a diagram showing an initial state of rate types when the system is started up.

FIG. 8 is an explanatory diagram of a line allocation method in the base station control device when there is no allocable half-rate free line.

FIG. 9 is a diagram showing a relationship between slots and channels in a transmission / reception device before and after receiving a rate setting change signal.

FIG. 10 is a flow chart of line selection allocation.

[Explanation of Codes] 1 base station 5 transceiver device 6 control station

Claims (3)

[Claims] 1. A base station and a control station for controlling the base station, wherein a plurality of lines can be used in one carrier by a transmitter / receiver in the base station and the mobile station moves at a plurality of transmission rates. In a multi-rate mobile radio communication system capable of transmitting and receiving information between a station and a base station, the transmission / reception device is capable of adaptively changing a transmission rate set for each line. Wireless communication system. 2. The determination means according to claim 1, wherein the control station determines whether or not there is a free line corresponding to the transmission rate capability of the mobile station that has made a call request.
When the judgment by the judgment means is that there is a free line, the free line is selected and line allocation is performed. When the judgment is that there is no free line, a rate type setting change signal is transmitted to the transmission / reception device, and the transmission / reception is performed. After changing the transmission rate of an empty line set to a rate type different from the transmission rate of the mobile station that made the call request in the device to the transmission rate of the mobile station, the line is allocated to the line subject to the change. A multi-rate mobile radio communication system comprising: 3. The multi-rate mobile radio communication system according to claim 1, wherein the transmission / reception device maintains the transmission rate of the line used for the communication after the mobile station completes the communication.