JPH10174151A - Mobile communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable real-time recovery of fault in a control zone by measuring a call loss rate for each control zone of each base station, cumulatively adding the number of times of call loss based on the call loss rate measured for each control zone and recovering the fault corresponding to the number of times of call loss. SOLUTION: A base station supervisory and control device 4 measures the call loss rate in the object control zone and discriminates whether the call loss rate is 100% or not and when the call loss rate is not 100%, the number of times of call loss in that control zone is set to but when the call loss rate is 100%, it is discriminated whether the number of times of call loss in the relevant control zone is more than 3 or not. When the number of times of call loss is less than 2, the base station supervisory and control device 4 reports the frequency of control transmitter/receiver at the relevant control zone base station to the base station and transmits a test call request signal to a transmitter/receiver 7 for test and fault recovery processing is proceeded by confirming call origination with a maintenance monitor terminal 5. When the number of times of call loss is more than 3, report setting processing is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile communication system, and more particularly to a failure recovery system for automatically detecting a system failure and recovering the failure.

[0002]

2. Description of the Related Art In a conventional mobile communication system, when a call from a mobile station cannot be made in each control zone,
A complaint from the user has recognized a system error. In addition, a call is made and received for a predetermined time in each control zone, and the probability of being unable to connect is counted as a call loss rate,
We report to maintenance monitoring terminal regularly.

[0003]

In the prior art, since only the control zone is reported periodically to the maintenance monitoring terminal, if the maintenance personnel does not monitor the call loss rate consciously, I did not understand the zone abnormality. Therefore, when the maintenance person does not notice the abnormality due to the call blocking rate, it is often possible to know the abnormality of the control zone by a complaint from the user. Therefore, conventionally, there has been a problem that it takes a long time to recover from a failure when an abnormality occurs in the system.

The present invention has been made in consideration of the above-described conventional problems, and has as its object to provide a mobile communication system capable of detecting occurrence of an abnormality in each control zone and recovering the failure in real time. is there.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a plurality of base stations for relaying incoming / outgoing calls from mobile stations, and monitors the operation status of each base station. Means for measuring a call blocking rate for each control zone of each base station in a mobile communication system having a base station monitoring and controlling device for accumulating the call blocking count based on the call blocking rate measured for each control zone. And means for restoring the control zone in accordance with the cumulatively added call loss count.

[0006]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a mobile communication system according to an embodiment of the present invention. In FIG. 1, 1, 2, 3,... N are wireless base stations arranged for each predetermined service area. Each base station relays incoming and outgoing calls from mobile stations. Also, the service area under the control of each base station is divided into a plurality of control zones, and each base station can wait up to six control zones. In FIG.
The control zones of the base station 1 are shown as 1a to 1f, and the control zones of the base station 3 are shown as 3a to 3f. In this embodiment,
As will be described in detail later, the call loss rate is measured in control zone units, the call loss count is cumulatively added in control zone units, and restoration is performed in control zone units according to the call loss count.

[0007] The base station monitoring and control device 4 is a device for monitoring the operation status of each base station, and reports the operation status of each base station to the maintenance and monitoring terminal 5 via the ISDN line. The maintenance monitoring terminal 5 is provided in an operation center (not shown), transmits various control signals to the base station monitoring and control device 4, and controls the base station monitoring and control device 4. In addition, the base station monitoring and control device 4 communicates with the mobile switch 6 and the ISDN.
Connected via a line. The mobile exchange 6 is an exchange that connects a general subscriber telephone and a mobile station to enable a telephone call between the general subscriber telephone and the mobile station. The test transceiver 7 is a device that confirms transmission of a control zone based on an instruction from the base station monitoring and control device 4 as described in detail later. In FIG. 1, the test transceiver 7 is provided only in the base station 1,
Actually, it is installed in each base station.

Next, a specific operation of the present embodiment will be described with reference to FIGS. First, FIG. 2 is a flowchart showing a process of detecting a failure for each control zone of each base station. In FIG. 2, first, the base station monitoring and control device 4 measures the call blocking rate of the target control zone (S20).
1). For example, when measuring the call loss rate of the control zone 1a of the base station 1, the base station 1 is controlled to make and receive calls for a predetermined time, and the probability of being unable to connect at that time is measured as the call loss rate. Since the call loss rate is well known in the art, a detailed description thereof will be omitted. When the measurement of the call loss rate is completed, the base station monitoring and control device 4 determines whether the call loss rate is 100% (S202). It is set to 0 (S203).

That is, in this embodiment, when the call loss rate of the control zone is 100%, it is determined that the control zone is abnormal, and when the call loss rate is not 100%, it is determined that the control zone is normal. The number of call drops is a numerical value that is cumulatively added using a counter (not shown) or the like for each control zone in the base station monitoring and control device 4. In the present embodiment, when the call loss rate is 100%, it is determined that the target control zone is abnormal.
It is not limited to 00%, and may be arbitrarily determined, for example, to be 95% or 98%.

On the other hand, if the call loss rate is 100% in S202, it is determined whether the number of call losses in the corresponding control zone is 3 or more (S204). If the number of call drops is 3 or less, the base station monitoring and control device 4 changes the frequency of the control TRX (transceiver device) of the control zone corresponding to the test transceiver 7 attached to the base station of the corresponding control zone. Notify (S205). In addition, the base station monitoring and control device 4 transmits a test call request signal instructing the corresponding test transceiver 7 to confirm transmission of the corresponding control zone (S20).
6).

When receiving the test call request signal, the test transceiver 7 checks the transmission using the previously notified frequency in the corresponding control zone. For example, if transmission confirmation of the control zone 1a is performed, the test transceiver 7
a and the maintenance monitoring terminal 5 of the operation center. The transmission confirmation is not limited to the maintenance monitoring terminal 5. When the transmission confirmation is completed, the test transceiver 7 determines the result of the transmission confirmation, sets the normal or abnormal based on the determination result in the test call control result report signal, and transmits the signal to the base station monitoring and control device 4.

Upon receiving the test call control result report signal, the base station monitoring and control device 4 confirms the result as will be described later in detail, and then performs a failure recovery process according to the number of call losses. Further, 1 is added to the number of call drops in the corresponding control zone (S2
07) Then, the call loss rate obtained in S201 is set in the internal periodic traffic report table (S208), and the processing of the target control zone ends.

On the other hand, if the call loss rate has not reached 100% in S202, or if the call loss count is 3 or more in S204, the flow directly proceeds to S208, and the call loss rate at that time is stored in the periodic traffic report table. Set and end the process. Here, the base station monitoring and control device 4 performs the processing of the flowchart of FIG.
.., N, and periodically for all control zones.

FIG. 3 is a flowchart showing the processing when the test call control result report signal is received from the test transceiver 7 as described above. In FIG. 3, upon receiving the test call control result report signal, the base station monitoring and control device 4 extracts a control result of transmission confirmation in the corresponding control zone from the signal (S301). Next, it is determined whether the result of the transmission confirmation is normal or abnormal based on the control result (S30).
2). Here, if the status is normal, the process ends. In this case, since the call loss rate of the corresponding control zone is usually 100%, it is determined to be abnormal. Also, S3
When the abnormality of the corresponding control zone is confirmed in 02, the base station monitoring and control device 4 determines whether or not the current call blocking number of the corresponding control zone is 1 (S303).

As described above, since the number of call drops is cumulatively added for each control zone by the counter in the base station monitoring and control device 4, for example, the control zone 1a of the base station 1 is the control zone subject to failure. Then, the base station monitoring and control device 4 reads the value of the current call loss count in the control zone 1a and determines whether or not the value is 1. Here, if the number of call drops in the corresponding control zone is 1, the base station monitoring and control device 4 controls the base station in the corresponding control zone to switch the currently used control TRX to the backup TRX (S30).
4). As a result, the fault in the corresponding control zone is immediately recovered, and the next time the processing in FIG. 2 is performed, the number of call drops in the corresponding control zone becomes zero. Further, in the present embodiment, the failure level is divided into three levels of level 1, level 2, and level 3 according to the number of call losses. If there is, switching to the spare TRX is performed.

On the other hand, if the number of lost calls is not 1 in S303, the base station monitoring and control device 4 determines whether the number of lost calls in the corresponding control zone is 2 (S305). If the number of call drops in the corresponding control zone is 2, the base station monitoring controller 4 controls the base station in the corresponding control zone to perform reset control (restart) of the control TRX (S306).
When the number of call drops is 2, it is a level 2 fault. When an abnormality occurs due to a software factor or the like, the reset control is normally performed to normally recover the fault in the control zone.

If the number of lost calls is not 2 in S305, the current number of lost calls in the corresponding control zone is 3, which is a level 3 failure with the highest level of failure. In the event of a level 3 fault, it is no longer possible to automatically recover the control zone by remote control.
Notifies the maintenance monitoring terminal 5 of the operation center that monitoring control of the corresponding control zone is impossible. Therefore,
In the case of a failure of level 3, a maintenance person of the operation center investigates and recovers from the failure of the corresponding control zone.

The base station monitoring and control device 4 performs the processing of FIG. 3 every time the test call control result report signal is received from the test transceiver 7 as described above, and the current control zone of the corresponding control zone at that time is processed. Level 1 to level 3 recovery processing is performed according to the number of call drops. By performing the processing of FIGS. 2 and 3 in this manner, the occurrence of a fault and the degree of the fault can be automatically detected for each control zone, and the fault can be recovered in real time according to the level of the fault. It can be carried out.

[0019]

As described above, according to the present invention, the number of call losses is cumulatively added based on the call loss rate for each control zone,
Since the recovery of the failure is performed according to the number of times of the call loss, not only the occurrence of the failure of each control zone can be automatically detected, but also the failure of the control zone can be recovered in real time. In addition, recovery according to the level of the failure due to the number of call drops can be performed, and the recovery of the failure can be performed efficiently. Therefore, the work of maintenance personnel can be made more efficient,
A highly reliable mobile communication system can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a mobile communication system of the present invention.

FIG. 2 is a flowchart for explaining the operation of the embodiment of FIG. 1;

FIG. 3 is a flowchart for explaining the operation of the embodiment of FIG. 1;

[Explanation of symbols]

 1, 2, 3,... N base station 1 a to 1 f control zone 3 a to 3 f control zone 4 base station monitoring and control device 5 maintenance and monitoring terminal 6 mobile switching unit 7 test transceiver

Claims (2)

[Claims] 1. A mobile communication system comprising: a plurality of base stations for relaying outgoing / incoming calls from a mobile station; and a base station monitoring control device for monitoring an operation state of each base station. Means for measuring a call loss rate for each control zone of the base station, means for cumulatively adding the number of call loss based on the call loss rate measured for each control zone, and control zone according to the cumulatively added call loss number. And a means for performing recovery of the mobile communication system. 2. The mobile communication system according to claim 1, wherein said adding means adds 1 to the number of call losses when the measured call loss rate is 100%.