JPH03234131A - Channel assignment system - Google Patents

Abstract

PURPOSE:To lower the probability of interference occurrence even before the effect of learning becomes eminent by using a predetermined radio channel or radio channel groups decided for each of radio base stations at the start of operation when the radio base station has no past operating result. CONSTITUTION:A different channel number is informed as a youngest channel number used by each of radio base stations 101-110 from a control station 300 at the start of operation of the radio base stations 101-110. Since the radio base stations 101-110 use the informed communication radio channel when a same priority is placed onto all the communication radio channels, a same channel interference in the communication radio channels used at least at first is avoided. Thus, the probability of interference occurrence of the radio base stations 101-110 is reduced even before the effect of learning becomes eminent.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a channel allocation method in a mobile communication system, and in particular, the present invention relates to a channel allocation method in a mobile communication system, and in particular, a method for allocating wireless channels that are used by countless base stations to communicate with mobile stations based on past usage results. Regarding the channel allocation method to be determined.

[Conventional technology]

In a mobile communication system that covers a service area by arranging a plurality of radio base stations, a method is adopted in which the same radio channel is geographically reused for effective frequency use. To achieve this, it is necessary to place wireless base stations and allocate channels based on accurate wireless zone design. However, this may not be possible inside a building, and various channel allocation methods have been proposed for this purpose. Each base station determines the radio channel to be used for communication with a mobile station based on its past usage record, that is, the radio channel to be used is determined by the learning effect so that the probability of occurrence of interference is reduced. method is one of them. In the case of such a conventional channel allocation method, each radio base station was configured to learn and store the learned information in order to avoid processing load on the control station.

[Problem to be solved by the invention]

The conventional channel allocation method described above has the drawback that the interference occurrence probability cannot be suppressed to a desired value until the learning effect appears.

[Means to solve the problem]

The channel allocation method of the present invention allows each of a plurality of wireless base stations that are arranged to cover the service area of a mobile communication system and are centrally controlled by a control station to allocate a wireless channel used for communication with a mobile station based on past usage history. In a channel allocation method in which the probability of interference occurrence is determined based on It is configured to use said group of infinite channels first.

Further, the channel allocation method of the present invention is configured such that the control station specifies the predetermined radio channel or the group of radio channels to each of the radio base stations when the radio base station starts operating. Good too.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a diagram for explaining the configuration of a wireless channel in one embodiment of the present invention, and FIG. 2 is a block diagram showing the system configuration of this embodiment.

In this embodiment, one channel of control radio channel 51 is used.
and 50 communication radio channels 1 to 50 are given, and each radio base station 101 to 110 has a control radio to which control radio channel 51 is assigned and all communication radio channels 1 to 50. A plurality of radio devices for communication that can be tuned to the radio device are arranged according to the traffic, and a control unit is provided to control both types of radio devices. Furthermore, the mobile station 200 can tune to all 51 channels including the control radio channel 51.

When setting a communication path between one of the radio base stations 101 to 110 and the mobile station 200, the radio base station selects a communication radio channel to which the mobile station 200 is tuned by a channel designation signal on the control radio channel 51. mobile station 200
The mobile station 200 then tunes the available communication radios to the same communication radio channel, and waits for a switching completion notification from the mobile station 200. The mobile station 200 tunes its radio to the specified radio channel for communication, and when the radio channel for communication is free from interference and usable, a notification of completion of switching is sent on the radio channel for communication, and when the radio channel for communication is unavailable, it sends out a notification of completion of switching. returns to the control wireless channel 51 and waits without transmitting the switching completion notification. If the wireless base station is able to receive the switching completion notification, it increases the numerical value indicating the usage priority of the communication wireless channel, and if it cannot receive the notification, it decreases and stores the value.

When determining the communication radio channel to be notified to the mobile station 200, the radio base stations 101 to 110 compare the numerical values indicating the usage priority stored for each of communication radio channels 1 to 50, and select the highest priority. I try to choose a wireless channel for calls with a high value.

By the way, if there is no history of using a radio channel for calls in the past, set the number indicating the usage priority to the same value for all radio channels for calls, and if the numbers indicating the usage priority are the same, use the one with the lowest channel number. When the system starts operating, all wireless base stations have the same usage priority for all call radio channels, and each wireless base station uses the call radio channel first. The radio channel is radio channel 1 for communication, which is the lowest numbered channel, and co-channel interference is likely to occur.

However, in this embodiment, when the wireless base stations 101 to 1]0 start operating, the control station 300 sends the following information as shown in FIG.
The radio base stations 101 to 110 are notified of different channel numbers as the smallest channel numbers used by each, and the radio base stations 101 to 110 are notified when all call radio channels have the same usage priority. Since the communication wireless channel is used, co-channel interference can be avoided at least in the initially used communication wireless channel.

Note that the group of wireless channels 1 to 5 for communication is connected to the wireless base station 1.
01 and notifies the radio base station 102 of a group of communication radio channels 6 to 10, thereby notifying the communication radio channels to be used first as a group, and the radio base stations 101 to 110 are notified. The same effect can be obtained even if the wireless communication channel with the lowest channel number in the group is used first.

〔Effect of the invention〕

As explained above, in the present invention, when using a channel allocation method in which each radio base station determines the radio channel used for communication with a mobile station in such a way that the probability of interference occurrence is small based on past usage results, each Wireless base stations are based on past usage records of wireless channels.

[Brief explanation of drawings]

FIG. 1 is a diagram for explaining the configuration of a wireless channel in one embodiment of the present invention, and FIG. 2 is a block diagram showing the system configuration of this embodiment. 1-50...Radio channel for communication, 51...Radio channel for control, 101-110...Radio base station,
200...Mobile station, 300...Control station.

Claims (1)

[Scope of Claims] 1. Past usage history of radio channels used for communication with mobile stations by each of a plurality of radio base stations arranged to cover the service area of the mobile communication system and centrally controlled by a control station. In a channel allocation method in which the probability of interference occurrence is determined based on A channel allocation method characterized in that the group of countless channels is configured to be used first. 2. Claim 1, wherein the control station is configured to designate the predetermined radio channel or group of radio channels to each of the radio base stations when the radio base station starts operating. channel allocation method.