JP4857226B2 - Failure monitoring apparatus and failure monitoring method for radio base station - Google Patents

Description

  The present invention relates to a failure monitoring apparatus and failure monitoring method for a radio base station, and more specifically, in a mobile communication system, by detecting occurrence of an abnormality that is not reported as a device failure from the radio base station side, The present invention relates to a failure monitoring apparatus and a failure monitoring method for notification.

In the mobile communication system, each radio base station has a function of automatically detecting a failure occurring in its own device and notifying the base station control device or monitoring device.
As shown in FIG. 1, the mobile communication system includes a plurality of radio base stations 20 (20-1 to 20-n) connected to a base station control device 30. Each radio base station 20 communicates with the mobile terminals 10 (10-1 to 10-n) located in the respective radio communication areas via radio channels, and the mobile terminals 10 are connected to the base station controller 30 and the mobile communication switching center 80. To the communication partner device connected to the exchange network NW. When a failure occurs in the radio base station 20 or the base station control device 30, an abnormality is detected by a failure monitoring function included in each device, and the failure is notified to the monitoring device 40.

  However, the fault monitoring function provided in each device may not be able to automatically detect an abnormal state that occurs during call connection for connecting the mobile terminal 10 to the communication partner device. In order to find such an abnormality, it is necessary for the monitoring device 40 to analyze the call processing history collected from each radio base station 20 and the base station control device 30.

  For example, in Japanese Patent Application Laid-Open No. 2004-274595 (Patent Document 1), when the ratio between the number of outgoing calls from the mobile terminal and the number of outgoing calls (call completion rate at the time of outgoing call) falls below a predetermined threshold, a plurality of sequences When an abnormality is detected in a specific sequence, a radio base station abnormality is detected by executing a suspicious test corresponding to this sequence.

  Further, in Japanese Patent Laid-Open No. 2005-086454 (Patent Document 2), an alarm is triggered by reception of a call completion rate lowering alarm that informs that the ratio between the number of outgoing calls and the number of completed calls (transmission completion rate) has decreased. The number of past outgoing calls is acquired from a communication device (for example, a radio base station) as a transmission source, and compared with a determination threshold value selected according to the traffic situation in the installation area of this communication device. It is estimated that a failure has occurred in the communication device.

JP 2004-274595 A JP 2005-086454 A

  However, in the method of detecting a failure of the radio base station by detecting a decrease in the normal call processing completion rate (call completion rate or call completion rate), the call volume depends on the location, time zone, and day of the week of the radio base station. Therefore, the decrease in the normal call processing rate is not necessarily caused by the device failure, and the device abnormality cannot be accurately estimated. For example, a wireless base station installed in an office district has a large amount of communication during the day, but the amount of communication decreases significantly at night. In addition, in wireless base stations installed near subway premises and tunnel entrances, mobile terminals that call from within trains leave the service area instantly, so compared to other wireless base stations There is a high probability of failure.

  This problem is caused by comparing the current call processing amount for each wireless base station with the past call processing amount for the same day of the week and the same time period, thereby changing the call amount depending on the location of the wireless base station and the time period. It is possible to absorb to a certain extent. However, in radio base stations installed in areas where the call volume is constantly low or where the call volume is low for a long time, slight fluctuations in the call volume are observed as a decrease in normal call processing volume. There is a possibility that the state of the base station is misjudged. In addition, there is a problem that a radio base station that does not perform call processing at all for a certain period of time, such as a subway at night, cannot detect an abnormality occurring during that period.

An object of the present invention is to provide a failure monitoring apparatus and a failure monitoring method capable of detecting an abnormality in a radio base station without erroneous detection due to traffic fluctuations even in an area where the call processing amount is constantly small. It is in.
Another object of the present invention is to provide a failure monitoring apparatus and a failure monitoring method capable of detecting an abnormality of a radio base station even during a time zone when no call is generated.

  In order to achieve the above object, the fault monitoring apparatus according to the present invention provides, for each radio base station (BS), the summation result of the latest period of call processing history stored in the call processing history file and the past number corresponding to this period. Comparing the average results for the week, and if the decrease in call processing volume in the latest period falls below a pre-specified threshold, the suspected BS estimation function that estimates that the radio base station is abnormal and the latest Depending on the amount of calls in the period, the aggregation period specifying function that dynamically switches between the aggregation period of the call processing history and the threshold for suspicious BS estimation, and the execution of the call connection test to the radio base station estimated to be abnormal And a failure determination function for determining the presence / absence of a failure in the radio base station from the test result.

More specifically, the present invention is a failure monitoring apparatus that periodically collects call processing history information from a plurality of radio base stations constituting a mobile communication network and monitors an abnormality of the radio base station,
A call processing history file for storing the call processing history information for a predetermined period collected from the plurality of radio base stations together with the date and time information for each radio base station;
A threshold table that includes a plurality of threshold table entries, and specifies the minimum call volume and threshold in association with the aggregation periods having different lengths in each table entry;
Aggregation for selecting the aggregation period T0 and threshold TH for estimating the suspected base station from the threshold table according to the amount of call processing history information of the specific radio base station stored in the call processing history file. Period identification means;
The call processing history information of the specific radio base station stored in the call processing history file is totaled retroactively from the latest date and time, the number of normal call processes and abnormal call processes within the total period T0, and the total Tally means for calculating the average number of normal call processes and abnormal call processes within a specific period of the past several weeks corresponding to the period T0;
A suspicious base station estimation means for evaluating a relationship between the aggregation result within the aggregation period T0 and the average aggregation result based on the threshold value T0 and estimating whether or not the specific radio base station is abnormal;
When the suspected base station estimation means estimates that there is an abnormality, it comprises failure determination means for instructing execution of a call connection test to the specific radio base station and determining whether or not there is a radio base station failure from the test result It is characterized by that.

In one embodiment of the present invention, the total period specifying means totals the call processing history information of a specific radio base station stored in the call processing history file retroactively from the latest date and time, and any threshold table The aggregation period T0 is the aggregation period in which the call processing amount counted within the aggregation period specified by the entry is equal to or greater than the minimum call volume specified by the threshold table entry, and the threshold value indicated by the threshold table entry is the threshold TH Select as
The totaling means sets the number of normal call processing and abnormal call processing calculated from the call processing history information in the totaling period T0 as the latest call processing total value Z0, and within a specific period of the past several weeks corresponding to the totaling period T0. The average number of normal call processing and the number of abnormal call processing calculated from the call processing history information is calculated as an average call processing total value Za,
The suspected base station estimation means calculates the latest normal completion rate R0 of call processing calculated from the latest call processing total value Z0 and the past average normal completion rate Ra calculated from the average call processing total value Za. A ratio (R0 / Ra) is obtained, and R0 / Ra is compared with the threshold value TH to estimate whether or not the specific radio base station is normal.

  The counting period specifying means counts the call processing history information of the specific radio base station stored in the call processing history file retroactively from the latest date and time, and within the counting period specified by the threshold table entry. When the counted call processing amount is zero, the specific radio base station is estimated to have zero traffic abnormality, and the failure determination means performs a call connection test on the specific radio base station estimated to have zero traffic abnormality. A command may be issued to determine whether there is a failure in the radio base station from the test result.

  In the present invention, according to the call processing amount of the latest period, the length and threshold of the aggregation period that is the basis of abnormality estimation are dynamically switched, and the radio base station that is estimated to be abnormal from the aggregation result of the call processing history Because it is instructed to execute the call connection test and determines the presence or absence of a failure from the test result, the radio base station installed in an area where the call volume is constantly low, or the time when the call volume becomes zero Even a radio base station having a band can determine abnormality with high accuracy.

Embodiments of a failure monitoring apparatus according to the present invention will be described below with reference to the drawings.
FIG. 2 shows a call processing history collection function of the radio base station 20-i (i = 1 to n).

  The mobile terminal 10 transmits an address acquisition request when connecting to the destination radio base station 20-i (SQ01). The address acquisition request is transferred to the base station controller 30 via the radio base station 20-i (SQ02). When receiving the address acquisition request, the base station control device 30 assigns an address to the mobile terminal 10 and returns a response message including the assigned address (SQ03). The response message is transferred to the mobile terminal 10 via the radio base station 20-i (SQ04). When receiving the response message, the mobile terminal 10 transmits an address setting completion notification (SQ05). The address setting completion notification is transferred to the base station controller 30 via the radio base station 20-i (SQ06).

  When communicating with another terminal device, the mobile terminal 10 transmits a call connection request to the radio base station 20-i (SQ10). The call connection request is transferred to the mobile communication switching center 80 via the radio base station 20-i and the base station control device 30 (SQ11, SQ12), and transferred from the mobile communication switching center 80 to the communication partner device. When the communication counterpart device responds, the response message is transferred to the mobile terminal 10 via the mobile communication switching center 80, the base station control device 30, and the radio base station 20-i (SQ13 to SQ15). The terminal enters a communication state. When the mobile terminal 10 ends the communication, it transmits a call disconnection request (SQ20). The call disconnection request is transferred to the mobile communication switching center 80 via the radio base station 20-i and the base station controller 30 (SQ21, SQ22).

  The radio base station 20-i has a call processing history collection function 200 that records history information indicating a call state for each mobile terminal when a control message designated in advance is received in the execution process of the call control procedure described above. I have.

FIG. 3 shows a block diagram of a monitoring device 40 that functions as a failure monitoring device according to the present invention.
The monitoring device 40 includes a processor 41, an input / output device 42, a communication interface 43 for communicating with the radio base stations 20 (20-1 to 20-n) and the base station control device 30 shown in FIG. It comprises a terminal interface 44 for connecting to the worker terminal 70 and memories 45 and 46. These elements are interconnected by an internal bus 47.

  In the memory 45, a configuration information table 51 for storing configuration information of a mobile communication system under the management of the monitoring device 40, a threshold table 52 storing thresholds for detecting a faulty base station described later, A call processing history file 53 storing call processing history information collected from the radio base station and a call processing total value file 54 storing call processing total values are formed.

The configuration information table 51 stores status information of each radio base station and other information in association with the identifiers of the radio base stations 20 (20-1 to 20-n).
As shown in FIG. 4, for example, the threshold table 52 includes a plurality of threshold table entries 520 (520-1 to 520-3) corresponding to the total period 521. Each table entry includes a minimum call volume 522 and a threshold. 523.

  In this embodiment, the total period 521 has three stages of 30 minutes, 180 minutes (3 hours), and 720 minutes (12 hours). The call volume means the total value of the normal call processing number and the abnormal call processing number handled by each radio base station, and the minimum call volume 522 indicated by the threshold value table 52 is collected from each radio base station. The minimum amount to be satisfied by the number of call processings within the counting period 521 is shown. The threshold value 523 will be described in detail later. Registration of the table entry in the threshold table 52 is performed using the input / output device 42 or the maintenance staff terminal 70.

  On the other hand, in the memory 46, as a program related to the present invention executed by the processor 41, a main control routine 61, a call processing history collection routine 62, a failure BS detection routine 63, a counting period specifying routine 64, and a call processing A number counting routine 65, a suspected BS estimation routine 66, and a failure determination routine 67 are prepared.

  The main control routine 61 starts the call processing history collection routine 62 periodically, and specifies the radio base station identifier (BS-ID) indicated by the configuration information table 45 to start the fault BS detection routine 43.

  The call processing history collection routine 62 collects the call processing history information 21 from each of the radio base stations 20 (20-1 to 20-n) at a predetermined cycle, for example, a 5-minute cycle, and the collected result is the call processing history file 53. To store. Each radio base station 20 reports to the monitoring device 40, for example, a call that has reached a call state as a normal processing call, and a call that does not enter a call state even after a predetermined time T has elapsed since it originated as an abnormal processing call. Calls currently being processed for which the predetermined time T has not elapsed will be reported next time. Each radio base station 20 has a call connection test function 22, and executes a call connection test in response to a command from the monitoring device 40 and reports the test result to the monitoring device 40 as will be described later. .

The call processing history file 53 includes, for example, a plurality of subfiles corresponding to the identifier (base station ID) 530 of the radio base station 20, as shown in FIG. The collected call processing history information 21 is stored as a history information record indicating the date 531, the call processing state 532, and the call identifier (or terminal ID) 533. The call processing state 532 can determine whether a call having the call identifier (or terminal ID) 533 is a normal processing call or an abnormal processing call.
In this embodiment, for example, call processing history information for the past 30 days is stored in the call processing history file 53, and history information that has passed the storage period is deleted from the call processing history file.

FIG. 6 is a flowchart showing the function of the failure BS detection routine 43.
In the failure BS detection routine 43, the processor 41 first activates the counting period specifying routine 64, refers to the call processing history subfile having the radio base station identifier (BS-ID) designated by the main control routine 61, The history information records for the total period (521) designated in the threshold table 52 are counted.

  The total period specifying routine 64 totals the call volume for the total period “30 minutes” indicated by the first table entry 520-1 of the threshold value table 52 retroactively from the latest record of the call processing history subfile. When the total call volume does not reach the minimum call volume 522 indicated by the table entry 520-1, the call volume for the total period “180 minutes (3 hours)” indicated by the second table entry 520-2 is totalized. If it does not reach the minimum call volume 522, the call volume for the aggregation period “720 minutes (12 hours)” indicated by the third table entry 520-3 is aggregated.

When the processor 41 confirms that the total call volume is equal to or greater than the minimum call volume 522 specified in the table entry 520-j, the value of the total period T0 for suspected BS estimation and the threshold value TH for abnormality estimation described later. As a result, the total period 521 and the threshold value 523 indicated by the table entry 520-j are selected.

  When the values of the parameters T0 and TH are specified, the processor 41 designates the total period T0 and starts the call processing number total routine 65. The call processing count totaling routine 65 counts the normal call processing count and abnormal call processing count within the counting period T0 retroactively from the latest record of the call processing history subfile, and sets the count result as the latest call processing count value Z0. Then, the failure BS detection routine 43 is reported (651).

  Next, the processor 41 designates the counting period T0, the same day of the week as the present day, and the number of weeks Nw, and starts the call processing number counting routine 65. The call processing number totaling routine 65 refers to the call processing history subfile, and totals the number of normal call processing and the number of abnormal call processing from the call processing history of the specified total period for the past several weeks on the same day of week. The average value of the results is reported to the faulty BS detection routine 43 as the average call processing total value Za (652).

  For example, when the total period T0 is 3 hours and the current date and time is 13:00 on Wednesday, the call processing history from 10:00 to 13:00 on Wednesday in the past Nw weeks is referred to, and the number of normal call processing and abnormal call processing The average number is reported as the average call processing summary value Za. If the call processing history for the past 30 days is stored in the call processing history subfile, designation of the number of weeks Nw is omitted, and the call processing count totaling routine 65 is stored in the call processing history subfile. The number of call processing histories for a specified total period on a specified day of the week may be totaled, and a weekly average value may be set as an average call processing total value Za.

When the total values Z0 and Za are determined, the processor 41 activates the suspicious BS estimation routine 66, and calculates the latest call processing from the normal call processing number and abnormal call processing number indicated by the latest call processing total value Z0 by the following formula. In the same manner as this, the normal call completion ratio Ra is calculated from the number of normal call processes and the number of abnormal call processes indicated by the average call processing total value Za (661).
Normal completion ratio = normal call processing count / (normal call processing count + abnormal call processing count)
Next, the processor 41 determines the ratio (R0 / Ra) of the normal call completion rate R0 of the latest call processing to the normal call completion rate Ra of the average call processing, and the abnormality estimation threshold value specified by the table entry 520-j of the threshold value table 52. Compare with TH (662). If the value of R0 / Ra is greater than or equal to TH, the processor 41 determines that the radio base station having the identifier BS-ID is normal, and ends the failure BS detection routine 43.

  When the value of R0 / Ra is lower than TH, the processor 41 determines that there is a possibility that an abnormality has occurred in the radio base station, activates the failure judgment routine 67, and sets the radio base station having the identifier BS-ID. The execution of the call connection test is instructed to the terminal (671). The radio base station 20 that has been instructed to execute the call connection test performs a simulation connection process (call connection test) when a call connection request is received from the mobile terminal by the call connection test function 22, and the test result is obtained. Notify the monitoring device 40.

  The processor 41 determines the test result notified from the radio base station 20 (672), and if it is determined that the radio base station 20 is operating normally, the fault BS detection routine 43 is terminated. If the test result indicates an abnormality (connection is not possible), the processor 41 determines that the radio base station 20 is abnormal, stores it in the configuration information table 51, and sends an identifier to the maintenance staff terminal 70 via the terminal interface 44. An alarm message indicating an abnormality of the radio base station having the BS-ID is transmitted, and the failure BS detection routine 43 is terminated.

  When the failure determination by the failure BS detection routine 43 is completed for one radio base station, the main control routine 61 designates the next radio base station identifier (BS-ID) indicated by the configuration information table 45 to detect the failure BS. Routine 43 is started. By repeating the above operation, failure determination using the call processing history 21 and the threshold value table 52 is performed for all wireless base stations registered in the configuration information table 45, and each wireless in the configuration information table 45 is determined according to the determination result. The status information of the base station is updated, and an alarm is output to the maintenance staff terminal 70.

  In the embodiment described above, the failure BS detection routine 63 activates the counting period specifying routine 63, and sets the counting period T0 and the threshold value TH in which the call volume counted from the call processing history is equal to or greater than the minimum call volume indicated by the threshold value table 52. The latest call processing total value Z0 and the average call processing total value Za are calculated according to the total period T0, and the ratio (R0 / Ra) between the latest normal completion rate R0 and the past average normal completion rate Ra is a threshold value. By comparing with TH, an abnormal radio base station was estimated.

  As a modification of the present invention, instead of calculating R0 / Ra, the ratio of the latest normal call processing count and the past average normal call processing count is compared with the threshold value TH, and the latest normal call processing count is calculated. The radio base station may be estimated to be abnormal when it decreases abnormally. Instead of the normal call processing number, the abnormal call processing number may be applied. This modification can be easily realized by changing a threshold value registered in advance in the threshold value table 52.

  Further, when the call volume value counted in the aggregation period (for example, 30 minutes) first designated in the threshold value table 52 is zero, the radio base station is estimated to have zero traffic abnormality, and the failure determination routine 67 is immediately started. The procedure after step 671 in FIG. 6 may be executed.

The figure which showed schematically the structure of the moving body communication system to which this invention is applied. The figure for demonstrating the collection function of the call processing log | history with which wireless base station 20-i is provided. The block block diagram which shows one Example of the monitoring apparatus 40 provided with the failure monitoring function of this invention. The figure which shows an example of the threshold value table 52 with which the monitoring apparatus 40 is provided. The figure which shows the structure of the call processing history file 53 with which the monitoring apparatus 40 is provided. The flowchart which shows one Example of the failure BS detection routine 63 which the processor of the monitoring apparatus 40 performs.

Explanation of symbols

10: Mobile terminal, 20: Radio base station, 30: Base station control device, 40: Monitoring device, 70: Maintenance staff terminal, 80: Mobile communication switching center,
41: processor, 42: input / output device, 43: communication interface, 44: terminal interface, 45, 46: memory, 51: configuration information table, 52: threshold table, 53: call processing history file, 54: call processing total file 61: Main control routine, 62: Call processing history collection routine, 63: Failure BS detection routine, 64: Total period specifying routine, 65: Number of call processing totals routine, 66: Suspected BS estimation routine, 67: Failure determination routine

Claims (5)

A failure monitoring device that periodically collects call processing history information from a plurality of radio base stations constituting a mobile communication network and monitors an abnormality of the radio base station,
A call processing history file for storing the call processing history information for a predetermined period collected from the plurality of radio base stations together with the date and time information for each radio base station;
A threshold table that includes a plurality of threshold table entries, and specifies the minimum call volume and threshold in association with the aggregation periods having different lengths in each table entry;
Aggregation for selecting the aggregation period T0 and threshold TH for estimating the suspected base station from the threshold table according to the amount of call processing history information of the specific radio base station stored in the call processing history file. Period identification means;
The call processing history information of the specific radio base station stored in the call processing history file is totaled retroactively from the latest date and time, the number of normal call processes and abnormal call processes within the total period T0, and the total Tally means for calculating the average number of normal call processes and abnormal call processes within a specific period of the past several weeks corresponding to the period T0;
A suspicious base station estimation means for evaluating a relationship between the aggregation result within the aggregation period T0 and the average aggregation result based on the threshold value T0 and estimating whether or not the specific radio base station is abnormal;
When the suspected base station estimation means estimates that there is an abnormality, it comprises failure determination means for instructing execution of a call connection test to the specific radio base station and determining whether or not there is a radio base station failure from the test result A fault monitoring apparatus characterized by that. The failure monitoring apparatus according to claim 1,
The totaling period specifying means totals the call processing history information of the specific radio base station stored in the call processing history file retroactively from the latest date and time, and the total specified by any one of the threshold table entries Select the total period during which the call processing amount counted within the period is equal to or greater than the minimum call volume specified in the threshold table entry as the total period T0 and the threshold indicated by the threshold table entry as the threshold TH,
The counting means sets the number of normal call processing and abnormal call processing counted from the call processing history information within the counting period T0 as the latest call processing counting value Z0, and within a specific period of the past several weeks corresponding to the counting period T0. The average number of normal call processing and the number of abnormal call processing calculated from the call processing history information is calculated as an average call processing total value Za,
The suspected base station estimation means calculates the latest normal completion rate R0 of call processing calculated from the latest call processing total value Z0 and the past average normal completion rate Ra calculated from the average call processing total value Za. A fault monitoring apparatus characterized by calculating a ratio (R0 / Ra) and comparing R0 / Ra with the threshold value TH to estimate whether or not the specific radio base station is normal. In the fault monitoring apparatus according to claim 1 or 2,
The counting period specifying means totals the call processing history information of the specific radio base station stored in the call processing history file retroactively from the latest date and time, and within the counting period specified by the threshold table entry If the counted call processing amount is zero, the specific radio base station is estimated to have zero traffic abnormality,
The failure is characterized in that the failure determination means instructs the specific radio base station that is estimated to have the zero traffic abnormality to execute a call connection test, and determines whether or not there is a failure in the radio base station from the test result Monitoring device. In the fault monitoring apparatus according to claim 1 or 2,
The counting means calculates the average normal call processing number and abnormal call processing number from call processing history information within a specific period of the past several weeks in which the day of the week and the time zone are the same as the counting period T0. A fault monitoring device characterized by the above. A wireless base station failure monitoring method by a failure monitoring device having a function of periodically collecting call processing history information from a plurality of wireless base stations constituting a mobile communication network,
A plurality of threshold table entries forming a threshold table, preliminarily designating a minimum call volume and a threshold in association with different aggregation periods;
Storing call processing history information collected from the plurality of radio base stations in a call processing history file for each radio base station together with date and time information;
A step of selecting a total period T0 and a threshold TH for estimating the suspected base station from the threshold table according to the amount of call processing history information of the specific radio base station stored in the call processing history file. When,
The call processing history information of the specific radio base station stored in the call processing history file is totaled retroactively from the latest date, the number of normal call processes and abnormal call processes within the total period T0, and the total Calculating an average normal call processing number and abnormal call processing number within a specific period of the past several weeks corresponding to the period T0;
Evaluating a relationship between a total result within the total period T0 and the average total result based on the threshold T0, and estimating whether the specific radio base station is abnormal;
If it is estimated that the specific radio base station is abnormal, the radio base station is instructed to execute a call connection test, and the test result is used to determine whether there is a fault in the radio base station. A characteristic fault monitoring method.

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