JPH11191897A - Method and system for selecting radio channel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid defective connection to a plurality of mobile terminals whose transfer rate differs from each other. SOLUTION: A mobile exchange station 1 makes call connections between a plurality of radio base stations 2 that manage and operate radio channels under its control and mobile terminals 3 resident in a communication zone. The radio base station 2 assigns a channel slot with a required transfer rate to calls from the mobile terminals 3 whose transfer rate differs. Both the radio base station 2 and the mobile terminal 3 select at least either a call communication system in a full rate system with a high transmission speed and a half rate system with a low transmission speed for mutual communication. The radio base station 2 receives any selection signal of the call communication system selected by the mobile terminal 3 and confirms idle channel slot information and sends the information to the mobile terminal 3. In the case that a plurality of the mobile terminal 3 are busy and a succeeding call is a non- telephone communication, two idle channel slots are selected optionally and assigned, as the connection by the full rate call communication system is required.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio communication system in which various types of calls having different transmission speeds coexist. A mobile terminal having a plurality of different transmission systems is provided with an idle radio channel for communication at a base station. The present invention relates to a slot selection method for allocating slots.

[0002]

2. Description of the Related Art In recent years, in a digital mobile communication system, a mobile terminal of a plurality of calls having different transmission speeds is required.
A wireless channel for communication managed by the base station, that is, an empty slot obtained by time-dividing the frequency is allocated.

[0003] As for those related to the time division multiple access (TDMA) system, for example, a communication channel designating method described in JP-A-4-373327 and JP-A-6-6290.
Japanese Patent Application Laid-Open No. 7-222237 discloses a mobile communication multiple channel allocation control method and a TDMA mobile communication wireless channel allocation method described in Japanese Patent Application Laid-Open No. 7-222237.

[0004] In the case of TDMA, a radio channel used by a plurality of users divides the time using one radio frequency in one frame into a number of time slots, and each user uses a different time slot. It has become.

[0005]

According to the prior art, when different radio channel slots are allocated to a plurality of mobile terminals, only a specific slot combination can be used, and the allocation method is fixed uniformly. Have been.

For this reason, even if a plurality of user mobile terminals are in a call and there is an empty slot, a call from a call system (full rate system) which occupies two non-telephone time slots at a high transmission rate. There is a problem that a call request cannot be allocated and connection cannot be made.

Accordingly, it is an object of the present invention to freely select a combination method of allocating an empty slot of a radio channel to mobile terminals of a plurality of calls having different transmission rates, and to efficiently use the empty slot. Another object of the present invention is to provide a radio channel selection method and system that eliminates the problem of being unable to connect depending on the situation by utilizing frequency.

[0008]

According to the radio channel selection method of the present invention, a plurality of radio base stations for managing and operating a radio channel owned by the mobile switching center under this management are provided. A call connection is made between a plurality of mobile terminals located in a communication area, and for a call from the mobile terminal having a different transmission speed, a channel in one frame in which the radio base station has a required transmission speed. In allocating slots, the radio base station and the mobile station terminal perform at least one of call communication of a full-rate scheme occupying two channel slots at a high transmission rate and a half-rate scheme occupying one channel slot at a low transmission rate. The mobile terminal can select a non-telephone service function, and the wireless base station can select a non-telephone service function. Receiving the selection signal of any one of the above-mentioned call communication systems, confirming the vacant channel slot information and transmitting it to the mobile terminal, and when a plurality of the mobile terminals are in a communication state and the next call is non-telephone In some cases, connection by the full-rate call communication method is required, and two empty channel slots are arbitrarily selected and assigned.

In this case, the radio base station manages a method of selecting an empty channel slot from among a predetermined number of channel slots constituting the one frame by a control unit composed of a CPU, and transmits and receives data to and from the mobile switching center. I do.

[0010] Further, some of the channel slots constituting one frame are allocated to control channels, and when two mobile terminals are in use by the half-rate method, two of the channel slots become empty channel slots. Put them in use, and when two of the mobile terminals are in full-rate mode, the first mobile terminal is in use in two of the channel slots and the second mobile terminal Is selected for use in the two channel slots.

That is, empty channel slots are managed in two call communication systems, a half-rate system and a full-rate system. When an empty channel slot is selected, call processing is performed using an arbitrary one.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a radio channel selection method and system according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing the present system.
FIG. 2 is a diagram showing a configuration of a radio base station, and FIG. 3 is a schematic diagram showing six time slots constituting one frame of a radio channel.

A mobile switching center 1 is provided, and a plurality of radio base stations 2 (2a, 2b,...) Connected to the mobile switching center 1.
・) Is arranged. The mobile switching center 1 has a function of connecting to a fixed network, and manages a plurality of radio base stations 2 to control a plurality of mobile terminal 3 (3a, 3b, 3c,...) Used by a user.
・) And call connection with fixed terminals.

The radio base station 2 has a function of transmitting and receiving at least one of the full rate system and the half rate system (a call system occupying one time slot at a low transmission rate), or both. I have. The wireless base station 2 manages and operates its own wireless channel, performs wireless communication with a plurality of mobile terminals 3 located in its own wireless communication area, and communicates with the mobile switching center 1. Call processing is performed between the two.

The mobile terminal 3 can select one of the above-described full-rate system, half-rate system, and non-telephone service function to make a telephone call by wireless transmission and reception.

Here, as shown in FIG.
Has an interface circuit 4 using I / O ports for transmitting and receiving to and from the mobile switching center 1, and a central processing unit (CPU) 5 for processing input / output signals therefrom.
In addition to a transmission / reception circuit 6 for inputting / outputting a transmission / reception signal to / from the mobile terminal 3 to / from the CPU 5, the transmission / reception circuit 6 includes a RAM 7 as a memory capable of writing and reading data signals and a ROM 8 as a read-only memory.

As shown in FIG. 3, the CPU 5 manages a method for selecting a time slot of an empty channel in, for example, six time slots constituting one frame, and transmits / receives data to / from the mobile switching center 1.

Next, the operation and operation of the present system having the above configuration will be described with reference to FIGS.
This will be described with reference to FIG.

Of the six time slots 10 to 15 constituting one frame, time slots 12 and 15 are allocated to the control channel. For example, when two mobile terminals 3 are in use by the half-rate method, as shown in FIG. 3, the time slots 10 and 11 out of the six time slots in one frame are in use.

On the other hand, when the two mobile terminals 3 are in use in the full rate mode, the first mobile terminal 3 is in use in the time slots 10 and 11, and the other second mobile terminals 3 are in use. The terminal 3 is in use in other time slots 11 and 14.

As described above, when the two mobile terminals 3 are in use by the half-rate method, the time slots 13,
Reference numeral 14 denotes an empty slot, but no mobile terminal can be assigned to the channel any more. That is,
When the third mobile terminal 3 attempts to perform non-telephone communication, the non-telephone communication requires handling of a full rate method using two time slots.

However, the time slot allocation method of the full rate method is only a combination of the time slots 10 and 13 or a combination of the time slots 11 and 14. In this case, communication cannot be performed even though the time slots 13 and 14 are vacant.

This point is solved in the present embodiment.
That is, the method of selecting a time slot can also be arbitrarily selected, and non-telephone communication can be performed by using the time slots 13 and 14 by using two time slots. In the case of the present embodiment, this is an example relating to non-telephony, and the present invention is not limited to such a method of selecting a time slot of a radio channel.

In the CPU 5, as shown in the conventional example, the time slot selection method is not fixed uniformly. That is, in the case of the full rate system, the present invention is not limited to the combination of the time slots 10 and 13 or the combination of the time slots 11 and 14.
For example, a combination of time slots 10 and 11 may be used, or a combination of time slots 13 and 14 may be used. In this way, slot management is performed by any combination of slots.

[0026]

As described above, the radio channel selection method of the present invention can perform communication by switching to either the full rate system or the half rate system, which is a call communication system. The connection with many mobile terminals can be realized by the effective use of the channel.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing an embodiment of a wireless channel selection system according to the present invention.

FIG. 2 is a block diagram illustrating a wireless base station which is a main part of the system according to the present embodiment.

FIG. 3 is a schematic diagram showing six time slots constituting one frame of a wireless channel in the present embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mobile switching center 2 Radio base station 3 Mobile terminal 4 Interface circuit 5 CPU 6 Transmission / reception circuit 7 RAM 8 ROM 10-15 Time slot in one frame

Claims (7)

[Claims] A mobile switching center manages and operates a radio channel owned by the mobile switching center under the control of a plurality of radio base stations and a plurality of mobile terminals located within a communication range of the radio base station. A radio channel selection method in which the radio base station allocates a channel slot in one frame having a required transmission rate to a call from the mobile terminal having a different transmission rate. The base station and the mobile station terminal can select and communicate at least one of a full-rate system that occupies two channel slots at a high transmission rate and a half-rate system that occupies one channel slot at a low transmission speed. In addition, the mobile terminal can select a non-telephone service function, The radio base station, any one of the call communication system selected by the mobile terminal Receiving the selection signal, confirming the vacant channel slot information and transmitting it to the mobile terminal, and when a plurality of the mobile terminals are in a communication state and the next call is non-telephone, the full-rate call communication is performed. System connection, the number of available channel slots is 2
A radio channel selection method characterized by arbitrarily selecting and assigning one. 2. The radio base station controls a method of selecting an empty channel slot from among a predetermined number of channel slots constituting one frame by a control unit comprising a CPU and communicates with the mobile switching center. The wireless channel selection method according to claim 1, wherein transmission and reception are performed. 3. Some of the channel slots constituting said one frame are allocated to control channels, and two of said channel slots are vacant when two of said mobile terminals are in use by said half rate method. Channel slots become available but they are used. When two of the mobile terminals are in the full rate mode, the first mobile terminal is used in two of the channel slots and the two mobile terminals are used. The second mobile terminal is the other 2
3. The radio channel selection method according to claim 2, wherein the radio channel is selected for use in one channel slot. 4. A mobile switching center, a full-rate system for managing and operating a radio channel owned by the mobile switching center under control of the mobile switching center and occupying two channel slots at a high transmission rate, and one channel slot at a low transmission rate. A call connection is established between a plurality of wireless base stations capable of performing wireless communication by selecting at least one of the half-rate communication methods of occupying the mobile terminal and the mobile base station located in the communication area by the mobile switching center. A plurality of mobile terminals having a non-telephone service function capable of selecting at least one of the full-rate method and the half-rate method and a non-telephone service function, for a call from the mobile terminal having a different transmission speed. Wherein the radio base station is configured to allocate a channel slot in one frame having a required transmission rate. Le selection system. 5. The radio base station receives a selection signal of any one of the call communication systems selected by the mobile terminal, searches for corresponding free channel slot information in the one frame, and 5. The wireless channel selection system according to claim 4, wherein vacant channel slot information is transmitted to said mobile terminal. 6. When the call communication system requested by the mobile terminal is the full rate system, the radio base station arbitrarily selects a combination of available channel slots and connects to the mobile terminal. The wireless channel selection system according to claim 5, wherein 7. The radio channel selection system according to claim 4, wherein the number of vacant channel slots constituting one frame is six.