JPH10285636A - Radio channel change timing decision system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To change the newly allocated interfering radio channel of an opposite side without changing the radio channel with results used over the long period of time when the radio channel interference has been detected in the radio channel allocation system of a mobile communication system. SOLUTION: A base station controller is provided with a radio channel change threshold value chart for which a radio channel interference generation sum-up and a radio channel interference monitoring period are set stepwise and a radio channel interference generation history for storing the radio channel interference generation time. Then, the number of times of the radio channel interference is counted up every time interference on the radio channel is detected and the result is collected with the radio channel change threshold value chart. In the case of matching with the radio channel interference generation sum-up of a certain stage, whether or not the interference is generated within a radio cannel interference monitoring period is checked by the radio channel interference generation history and the radio channel is changed when all the interference is generated within the radio channel interference monitoring period.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio channel assignment system for a mobile communication system, and more particularly to a radio channel change timing decision system for changing a radio channel based on a radio channel interference measurement result.

[0002]

2. Description of the Related Art Conventionally, mobile communication systems have been disclosed in
If there is a transceiver that has received an interference wave power exceeding a predetermined threshold value as described in -33033, the transceiver is closed and the wireless channel is changed.

[0003] In particular, when changing the radio channel, the only decision factor is whether or not there is a usable radio channel, and there is no other decision factor.

[0004]

A first problem is that there is a radio channel that can be used as a judgment material for radio channel change when an interfering radio force exceeding a threshold value on a radio channel is received by a transceiver. Since there is no choice but to make a change, the wireless channel is changed immediately when wireless channel interference occurs.

[0005] The reason for this is that if the radio channel is immediately changed just because it receives the interference wave power exceeding the threshold value without taking the stability of the radio channel into account, the radio channels that are giving interference simultaneously change. This is because the possibility is high that the wireless channel is eventually switched to affect the surrounding cells using the stable wireless channel and spread the ripples. It is also conceivable that the wireless channel is constantly changed.

[0006] It is an object of the present invention to provide a radio channel change timing determining method that reduces the influence on other radio channels.

[0007]

According to the radio channel change timing determination method of the present invention, when interference is detected on a radio channel, a radio channel change threshold value table and a radio channel interference occurrence history are referred to, and a radio channel change history is determined. It has means for determining the change timing.

Since the wireless channel change timing is determined using the wireless channel change threshold value table and the wireless channel interference occurrence history, stable wireless channel change can be prevented as much as possible. As a result, it is possible to minimize the influence on cells using a stable wireless channel in the vicinity.

[0009]

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

Referring to FIG. 1 showing an embodiment of the present invention, a system for applying a radio channel change method in mobile communication is provided with mobile terminals 10 scattered in a radio zone.
And a radio base station connected to the mobile terminal 10 by a radio line, transmitting and receiving signals using TDMA (time division multiple access) 3 channels / carrier as an access method, and monitoring line quality for radio line switching. Bureau 20,
A base station controller 30 for setting and switching of a wireless channel, remote monitoring and control of the wireless base station 20, and monitoring and controlling the wireless channel; and the mobile terminal 10 and the public through the wireless base station 20 and the base station controller 30. It comprises a mobile telephone exchange 40 for connecting subscribers (not shown) of the network or mobile terminals.

The radio base station 20 includes an antenna 1, a plurality of transceivers 21 to 2n from # 1 to #N connected to the antenna 1 for each sector, and an interface for connecting to the base station controller 30. The base station controller 30 includes a circuit 3 and a control unit 4 for controlling the transceiver and the interface circuit. The base station controller 30 includes an interface circuit 5 for connecting to the radio base station 20 and the mobile telephone exchange 40, respectively.
6, a speech path switch 7 for accommodating these interface circuits and forming a speech path, and interface circuits 5, 6
A central control device 9 for controlling the communication path switch 7; and a storage device 8 on which data is written and read by the central control device.

FIG. 2 shows a control unit 4 of the radio base station in FIG.
FIG. 3 is a block diagram showing details of a central control unit 9 of the base station controller and an in-use radio channel interference monitoring unit 41 that monitors interference of an in-use radio channel, and an idle radio that monitors interference of an idle radio channel. Channel interference monitoring unit 42
And a data management unit 43 for managing data. The in-use radio channel interference monitoring unit 41 includes a radio channel interference measurement execution unit 411 that periodically performs interference measurement on a radio channel in use, a radio channel interference measurement result reception unit 412 that receives interference measurement results, and And a wireless channel interference information transmitting unit 413 for transmitting wireless channel interference result information to the base station controller 30.

An idle radio channel interference monitoring unit 42 is a radio channel interference measurement execution unit 421 that periodically executes interference measurement on an idle radio communication channel, and a radio channel interference measurement result reception unit that receives interference measurement results. Part 422
And a radio channel interference information transmitting unit 423 that transmits radio channel interference result information to the base station controller 30. The data management unit 43 includes a data reception unit 431 that receives and processes new wireless channel data set in the transceiver from the base station control device 30, a data storage unit 432 that stores and processes the received data, A data transfer unit 433 for performing data transfer processing. The central control unit 9 receives the used radio channel interference information from the radio base station 20 and performs the interference detection processing. The busy communication channel interference detection unit 91 receives the vacant radio channel interference information and performs the idle detection processing. Wireless channel interference detector 92
And a wireless channel change control unit 93 that changes the wireless channel based on the degree of interference of the wireless channel and transmits the changed wireless channel to the wireless base station. The in-use radio channel interference detection unit 91 includes a radio channel interference information reception unit 911 that receives in use radio channel interference information, and a radio channel interference detection unit 912 that detects interference of a certain level or more from the radio channel interference information. The idle radio channel interference detecting unit 92 is a radio channel interference information receiving unit 921 that receives idle radio channel interference information, and a radio channel that detects that interference of a certain level or more is continuously occurring from the interference information. An interference detection unit 922 is provided. The wireless channel change control unit 93 counts up the number of interferences detected by the wireless channel interference detection units 912 and 922 and stores the number of interferences in the system data. A wireless channel change threshold check unit 932 for searching for a location that matches the cumulative wireless channel interference occurrence in the wireless channel change threshold table of FIG. A radio channel interference occurrence history check unit 933 for confirming from the radio interference occurrence history of FIG. 4 that the number of times of interference has occurred within the radio channel interference occurrence period of FIG. Radio channel changing unit 9 for selecting a radio channel to be set in the transceiver
34, and a wireless channel change data transmitting unit 935 that transmits the wireless channel after the wireless channel change to the wireless base station.

FIG. 3 is a diagram for explaining an example of a radio channel change threshold value table in this embodiment. A radio channel change threshold table is usually provided for each sector,
The threshold value has multiple levels and is stored in the storage device 8 of the base station controller 30. In this example, the wireless channel interference occurrence total and the wireless channel interference monitoring period are set to # 1 to # 10.
A table in the case of dividing into 0 stages is illustrated. FIG. 4 is a diagram for explaining an example of a radio channel interference occurrence history in this embodiment. The radio channel interference occurrence history is usually provided for each transceiver indicated by 21 to 2n in FIG. 1 and is stored in the storage device 8 of the base station control device 30.

Next, the operation of this embodiment will be described with reference to FIGS. 5 and 6 showing the procedure of the radio channel change timing decision method in one embodiment of the present invention and FIGS.

The busy communication channel interference monitoring unit 41 of the radio base station 20 (or the idle radio channel interference monitoring unit 4)
The wireless channel interference measurement execution unit 411 of (2) (or 4)
At 21), a wireless channel interference measurement is performed on the transceiver (step 1: S1), and the wireless channel interference measurement result is transmitted from the transceiver to the wireless channel interference measurement result receiving unit 4.
12 (or 422), the radio channel interference information transmitter 413 (or 423) transmits it to the central controller 9 of the base station controller 30 (S2).

The radio channel interference information received (S3) by the radio channel interference information receiving unit 911 of the central control unit 9 is obtained when the radio channel interference detecting unit 912 determines that the radio channel interference is above a certain level. In (S4), the occurrence of wireless channel interference is reported to the wireless channel interference frequency management unit 931. After the wireless channel interference frequency management unit 931 counts up the number of wireless channel interference (S5),
The wireless channel change threshold check unit 932 stores the number of times of wireless channel interference and C1 of the cumulative wireless channel interference in the wireless channel change threshold table of FIG.
To C10 and search for a matching part (S6).
If the number of wireless channel interference matches any one of C1 to C10 (S7), for example, if the number matches C3, the wireless channel interference monitoring period H3 is read out and the wireless channel interference occurrence history check unit 932 generates C3 in H3. (S8) If the error occurred in H3, the wireless channel is changed by the wireless channel changing unit 934 (S8).
9) The changed wireless channel is transmitted from the wireless channel change data transmitting unit 935 to the control device 4 of the wireless base station 20 (S10).

The control unit 4 of the radio base station 20 transmits the radio channel change data from the base station control device 30 to the data reception unit 4.
The data is received at 31 and transferred to the data storage unit 432. The data accumulation unit 432 transmits a confirmation signal to the base station control device 30 by accumulating the new radio channel, and changes the data transmission unit 433 to a transceiver (any one of 21 to 2n) in which radio channel interference has occurred. The notified wireless channel is notified.

Next, the case where the radio channel used by the newly installed radio base station B causes radio channel interference with the cell of the radio base station A already using the stable radio channel is shown in FIGS. This will be described with reference to FIG.

FIG. 7 shows an example in which an arbitrary value is actually set in the radio channel change threshold value table. This table is for radio base station A
-It is assumed that the same value is set for both the radio base stations B. FIG. 8 shows a radio channel interference occurrence history of the radio frequency F1 used by the transceiver T1 of the radio base station A. FIG. 9 shows a radio channel interference occurrence history of the radio channel F2 used by the transceiver T2 of the radio base station B. FIG.
Indicates a radio channel change point when the radio channel F1 used by the transceiver T1 of the radio base station A and the radio channel F2 used by the transceiver T2 of the radio base station B interfere with each other. Show. Also, the radio channel F
1 and the radio channel F2 are the same channel and the radio base station B
The time when the radio channel F2 is allocated to the transceiver T2 is 0:00:00 on November 17, 1996. First, paying attention to the wireless channel F1, after the wireless channel F2 is allocated to the transceiver T2 of the wireless base station B, the wireless channel interference occurs twice and a total of 10 times occurs.
Of the cumulative number of occurrences of the radio channel interference in the radio channel change threshold value table of FIG.
If the number of times has occurred, it is understood that the channel change is performed. In view of the wireless channel interference occurrence history shown in FIG. 8, it has been more than 20 hours before the wireless channel interference reaches ten times, and the wireless channel change is not executed because the condition of # 4 in the wireless channel change threshold value table is not met. . Next, focusing on the wireless channel F2, since the wireless channel interference generated twice occurs within 2 hours, the wireless channel change is executed because the condition of the wireless channel change threshold # 1 in FIG. 7 is met. Is done.

Looking at the above situation in FIG. 10, the radio channel F2 has reached the radio channel change threshold value at the point of time when the radio channel interference occurs twice (P1), so that the radio channel change is executed. .

[0022]

The first effect is that a radio base station is newly installed when the radio channel is already stable between cells, and that the radio base station causes interference with other cells. Is assigned, the effect on the radio channel used in another cell is suppressed as much as possible so that the ripple of the radio channel change operation is not spread.

The reason is that not only the radio channel change threshold value is considered only based on the number of radio channel interferences but also the radio channel interference monitoring period. This is because the wireless channel is changed with a small amount of wireless channel interference for a wireless channel having a short usage time so that the wireless channel is not changed by the interference.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a system to which a wireless channel change method is applied in mobile communication according to an embodiment of the present invention.

FIG. 2 is a block diagram showing some of the components of FIG. 1;

FIG. 3 is a table showing an example of a wireless channel change threshold value in the embodiment.

FIG. 4 is a table showing an example of a radio channel interference occurrence history in this embodiment.

FIG. 5 is a flowchart illustrating a procedure for changing a wireless channel in mobile communication according to an embodiment of the present invention.

FIG. 6 is a flowchart illustrating a procedure for confirming a threshold value for changing a wireless channel in mobile communication according to an embodiment of the present invention.

FIG. 7 is a table in which an arbitrary value is set as a wireless channel change threshold value in the embodiment.

FIG. 8 shows a wireless channel interference occurrence history assuming that wireless channel interference actually occurred in this embodiment.

FIG. 9 shows a radio channel interference occurrence history assuming that radio channel interference actually occurred in this embodiment.

FIG. 10 is a graph showing an example of wireless channel change timing in this embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Antenna 3,5,6 Interface circuit 4 Control part 7 Communication path switch 8 Storage device 9 Central control device 10 Mobile terminal 20 Radio base station 21-2n # 1 transceiver #N transceiver #Base station controller 40 Automobile Telephone exchange 41 In-use radio channel interference monitoring unit 42 Unoccupied radio channel interference monitoring unit 43 Data management unit 91 In-use radio channel interference detection unit 92 Unoccupied radio channel interference detection unit 93 Radio channel change control unit 411, 421 radio channel Interference measurement execution units 412, 422 Radio channel interference measurement result reception units 413, 423 Radio channel interference information transmission units 431 Data reception units 432 Data storage units 433 Data transmission units 911, 921 Radio channel interference information reception units 912, 922 Radio channel interference Detector 931 Wireless channel Count management unit 932 radio channel change threshold checking part 933 radio channel interference occurrence history checking unit 934 radio channel switching unit 935 radio channel change data transmission unit

Claims (6)

[Claims] 1. A radio channel change timing determining method in a mobile communication system, comprising the following functions: B) In the autonomous distributed dynamic channel allocation method for the purpose of improving the frequency use efficiency and reducing the burden of the radio channel arrangement design work, interference measurement on the radio channel is performed for each radio channel. B) The measured interference result is stored as a history in the memory of the base station controller. C) A threshold table for changing the wireless channel is held in advance. D) The accumulated interference result history is applied to a radio channel change threshold value table, and when the threshold value is exceeded, the corresponding radio channel is changed. 2. When the radio channel interference measurement is performed,
2. The radio channel change timing determining method in a mobile communication system according to claim 1, further comprising: "means for performing radio channel interference measurement during use"; and "means for performing radio channel interference measurement during idle time". 3. The method according to claim 1, further comprising, when storing the interference measurement result in a memory of the base station control device, means for dividing the number of times of occurrence of interference on each radio channel and the time of occurrence of interference into a history table. Item 2. A radio channel change timing determining method in the mobile communication system according to Item 1. 4. The wireless channel change threshold value table,
2. The radio channel change timing determination method in a mobile communication system according to claim 1, wherein the radio channel interference generation cumulative number (times) and the radio channel interference monitoring period (H). 5. In the wireless channel change threshold value table, “cumulative occurrence of wireless channel interference (times)” is # 1 = 2,
# 2 = 4, # 3 = 7, # 4 = 10, # 5 = 14, # 6 =
19, # 7 = 25, # 8 = 32, # 9 = 40, # 10 =
2. The radio channel change timing determining method in a mobile communication system according to claim 1, wherein the radio channel change timing is 50. 6. In the radio channel change threshold value table, “radio channel interference monitoring period (H)” is set to # 1 = 2,
# 2 = 5, # 3 = 10, # 4 = 20, # 5 = 50, # 6
= 80, # 7 = 120, # 8 = 170, # 9 = 230,
The wireless channel change timing determination method in a mobile communication system according to claim 1, wherein # 10 = 300.