JP5263959B2 - CIO value setting management device, mobile radio communication system, CIO value setting method using cell stay time information of mobile station, CIO value setting management program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To set a CIO value on the basis of handover statistical information in an actual operation without executing a running test or the like. <P>SOLUTION: This invention relates to a CIO setting management device (OMC1, 2) of a base station (eNB11-14) to which a plurality of mobile stations (UE21) are wirelessly connected, wherein a control means (control sections 100, 103) refers to cell stay time information included in communication history information (UE History Information) transmitted from the base station, retrieves a short time stay cell whose cell stay time is shorter than a stipulated value, and generates and outputs traffic information capable of outputting the CIO value for reducing the number of handover calls through the short time stay cell. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a CIO value setting management apparatus, a mobile radio communication system, a CIO value setting method using cell stay time information of a mobile station, and a CIO value setting management program. The present invention relates to a technique suitable for use for updating a CIO value, which is a radio quality correction value set in each cell, so that the number of handover calls passing through a short-term cell decreases.

  A CIO (Cell Individual Offset) value is a parameter managed by the base station, and is used for correcting a radio quality result measured by the mobile station from the base station. The mobile station notifies the base station of the handover destination cell candidate using the CIO value corrected by the CIO value. By appropriately correcting the CIO value, it is possible to reduce handovers via the short stay cell.

  A number of applications have been filed for the technique for recording the number of handover calls described above. For example, Patent Document 1 discloses a technique for broadcasting a cell individual offset indicated by a CIO value. Patent Document 2 discloses a technique in which cell information is recorded in each of handover operation information and current operation information immediately before a handover operation. Patent Document 3 stores handover frequency as the number of handovers per 10 seconds, for example. A technique for controlling a cell candidate of a handover destination of each mobile station based on the handover frequency is disclosed.

Japanese Patent Laying-Open No. 2005-51767 (paragraphs “0090” to “0092”) JP 2008-16970 (paragraph “0043”, FIG. 3) JP-A-7-193850 (paragraphs “0023” to “0024”)

  By the way, in calculating the above-described CIO value, it is common for a maintenance person to actually perform a driving test or the like in each cell, and repeatedly set the CIO value and repeat the test so that the number of handovers is minimized. It is. However, in order to calculate a CIO value by performing a running test, costs such as labor costs are incurred.

  Further, in a running test, it is not realistic because it is not a CIO value calculated based on handover statistical information in actual operation. Furthermore, since the operating state changes from time to time due to factors such as the new installation and abolition of base stations, the construction of new buildings, the opening of roads and trains, etc., it is necessary to carry out costly driving tests each time.

(Object of invention)
An object of the present invention is to provide a CIO value setting management device, a mobile radio communication system, and a mobile station cell residence time information that can set a CIO value based on handover statistical information in actual operation without performing a running test or the like. It is to provide a CIO value setting method and a CIO value setting management program used.

  A first CIO value setting management device of the present invention is a CIO setting management device of a base station to which a plurality of mobile stations are wirelessly connected, and cell stay time information included in communication history information transmitted from the base station. And a control unit that searches for a short-term staying cell having a cell staying time shorter than a specified value, and generates and outputs traffic information capable of updating a CIO value that reduces the number of handover calls via the short-term staying cell.

  The second mobile radio communication system of the present invention includes one or more base stations to which a plurality of mobile stations are wirelessly connected, and one or more base stations connected to each of the one or more base stations, and CIO setting management capable of message communication with each other. A mobile radio communication system comprising a device, wherein the base station accumulates communication history information of the mobile station each time a call is released, and reads the accumulated communication history information for each preset transmission cycle; Transmitting means for transmitting to a connected CIO setting management apparatus, the CIO setting management apparatus refers to cell stay time information included in communication history information transmitted and received from a base station, and performs handover in a time shorter than a specified value Control that searches for short-term staying cells, generates traffic information that can be used to calculate wireless quality correction values that reduce the number of handover calls via short-term staying cells, and transmits the traffic information to the base station Equipped with a stage.

  The CIO value setting method using the cell stay time information of the third mobile station according to the present invention includes one or more base stations to which a plurality of mobile stations are wirelessly connected and one or more base stations connected to each of the one or more base stations. A CIO value setting method using cell stay time information of a mobile station, which is used in a wireless communication system comprising a CIO setting management device capable of message communication with each other, wherein the base station performs call release. A first step of storing the communication history information of the mobile station every time the mobile station is read out, reading the stored communication history information for each preset transmission cycle, and transmitting it to the connected CIO setting management device; The cell stay time information included in the communication history information transmitted and received from the base station is referred to search for a short stay cell that has been handed over in a time shorter than the specified value, A second step of generating and transmitting a calculable traffic information radio quality correction value to reduce the bus number of calls to the base station.

  A fourth CIO value setting management program according to the present invention is a CIO value setting management program for a CIO setting management device of a base station that is executed on a computer and to which a plurality of mobile stations are wirelessly connected. Referring to the cell stay time information included in the communication history information transmitted from, a search process for searching for a short stay cell whose cell stay time is shorter than a specified value, and a CIO value for reducing the number of handover calls via the short stay cell Output processing that generates and outputs traffic information that can be updated.

  According to the present invention, the CIO value setting management device, the mobile radio communication system, and the cell stay time information of the mobile station that can set the CIO value based on the handover statistical information in the actual operation without performing a running test or the like. A CIO value setting method and a CIO value setting management program can be provided.

  The reason is that the CIO set value management device refers to the cell stay time information included in the communication history information transmitted from the base station, searches for a short stay cell whose cell stay time is shorter than the specified value, This is because the traffic information that can update the CIO value that reduces the number of routed handover calls is generated and output, so that the CIO value can be set based on the actual operation regardless of the running test or the like.

It is a block diagram which shows the structure of the mobile radio | wireless communications system by embodiment of this invention. It is a figure which shows an example of the data structure of the information holding part which the CIO setting management apparatus of the mobile radio | wireless communications system by embodiment of this invention has. It is a figure which shows an example of the data structure of the information holding part which the base station of the mobile radio | wireless communications system by embodiment of this invention has. It is a figure which shows the operation | movement sequence in the pre-processing stage between each component apparatus of the mobile radio | wireless communications system by embodiment of this invention. FIG. 3 is an operation sequence diagram showing an operation of the mobile radio communication system according to the first embodiment of the present invention. It is an operation | movement sequence diagram which shows the CIO value automatic update process operation | movement of the mobile radio | wireless communications system by the 2nd Embodiment of this invention. It is a figure which shows an example of the cell arrangement | positioning shown in order to demonstrate the specific operation | movement of the mobile radio | wireless communications system by the 2nd Embodiment of this invention. It is a figure which shows an example of the data structure set to the information holding part at the time of the CIO value automatic update process of the CIO value setting management apparatus by the 2nd Embodiment of this invention.

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

(Configuration of the first embodiment)
FIG. 1 is a block diagram showing a configuration of a mobile radio communication system according to the first embodiment of the present invention.

Here, as a mobile radio communication system, in order to realize multimedia communication including video and audio, and high-speed communication of 100Mbps, which enables the transmission of low-latency, 3 3GPP (3 ^rd Generation Partnership Project) LTE (Long, also known as 9G wireless technology)
A mobile radio communication system 10 (3GPP recommendation TS36.300) using Term Evolution will be described as an example.

  Referring to FIG. 1, a mobile radio communication system 10 according to a first embodiment of the present invention includes one or more bases to which a plurality of mobile stations (here, only UE 21 is shown as a mobile station) are connected by radio. A CIO value setting management device (hereinafter referred to as OMC 1 and 2) that is connected to each of one or more eNBs 11 to 14 and capable of message communication with each other.

  One or more OMCs 1 and 2 are installed, and the OMCs 1 and 2 are connected to the plurality of eNBs 11 to 14, respectively. Message communication is possible between all the OMCs 1 and 2 without one eNB 11 (12 to 14) being connected to the plurality of OMCs 1 and 2. At this time, the protocol used for message communication between the OMCs 1 and 2 may use IP (Internet Protocol) or other protocols. The network topology may be a mesh type, or other network topology may be used.

  Note that the CIO values managed by the eNBs 11 to 14 hold the CIO value of the own cell and the CIO value of the adjacent cell in units of the cells 31 to 36, and the CIO value and the cell of the adjacent cell 33 held by the cell 31. The CIO values of the adjacent cells 33 held by the 32 need not be the same value.

  The OMC 1 includes a control unit 100 and an OMC information holding unit 101. The control unit 100 refers to communication history information (UE History Information: UE cell stay time information) transmitted from the subordinate eNBs 11 and 12, and the short stay cell whose cell stay time is shorter than a specified value (threshold value described later). As a control means for generating and outputting traffic information capable of updating the CIO value for reducing the number of handover calls via the short stay cell. Details will be described later.

  The OMC information holding unit 101 includes a maintenance person setting information unit 111 and a CIO value update related information holding unit 112 as shown in FIG. 2 as an example of the data structure.

  The maintenance person setting information holding unit 111 is “CIO value update period”, “time when cell stay time is determined to be short-term”, “CIO value automatic setting availability”, “weight value”, which are information set by the communication carrier. Hold. Here, the “CIO value update cycle” is a cycle in which the CIO value is updated. The “time for determining that the cell stay time is short-term” is a time threshold for determining that the cell stay time is short when searching for communication history information (UE History Information). From 1 second to 1 millisecond can be considered. “CIO value automatic setting availability” is a flag for setting whether or not to enable automatic updating of the CIO value. The “weight value” refers to a value weighted for each continuous range in which the ratio of the number of short-term stay calls to the number of handover calls is constant.

  The CIO value update related information holding unit 112 holds a plurality of CIO related information created for each cell implemented by the eNBs 11 and 12 under the OMC1, and specifically, an average value of weight as cell internal information, itself Cell weight value, and the number of handover calls to neighboring cells, the number of short-term stay calls, the ratio of short-term stay calls to the number of handover calls, and the weight value obtained from the ratio of short-term stay calls to the number of handover calls Including.

  The OMC 2 has the same configuration as the OMC 1 described above. That is, the OMC 2 includes a control unit 103 and an OMC information holding unit 102. The OMC information holding unit 102 includes a maintenance person setting information unit 111, a CIO value, and an example of the data structure shown in FIG. And an update related information holding unit 112.

  Returning to FIG. The eNB 11 includes a control unit 110 and an eNB information holding unit 201. The control unit 110 accumulates communication history information (UE History Information) every time a call is released, reads out the accumulated communication history information for each preset transmission cycle, and transmits it to the connected OMC 1. Have.

  The eNB information holding unit 201 includes a maintenance person setting information holding unit 211 and a communication history information holding unit 212, as an example of the data structure is shown in FIG.

The maintenance person setting information holding unit 211 holds communication history information (UE History Information) that is information set by the communication carrier. Here, the communication history transmission cycle is a cycle in which the eNB 11 transmits the communication history information to the OMC 1. The communication history holding unit 212 is communication history information (UE) about the UE 21 released by the eNB 11 when the call is released.
Accumulate multiple History Information).

  In addition, eNB12, eNB13, and eNB14 have the same configuration as eNB11 described above, and control unit 120, eNB information holding unit 202, control unit 130, eNB information holding unit 203 control unit 140, and eNB information holding unit 204, respectively. Have Also, each of the eNB information holding units 202, 203, and 204 has a data structure similar to that of the eNB information holding unit 201, as shown in FIG.

(Operation of the first embodiment)
Next, the operation of the mobile radio communication system 10 according to the first embodiment of the present invention will be described with reference to the operation sequence diagrams shown in FIGS.

  FIG. 4 is a diagram showing an operation sequence in a pre-processing stage between the constituent devices of the mobile radio communication system 10 according to the first embodiment of the present invention. Here, eNBs 11 to 14, OMC1, OMC2 and The flow of operation during is shown.

  Referring to FIG. 4, the communication carrier first sets information used for the CIO value automatic update process in the OMC information holding units 101 and 102 of OMC1 and OMC2. Specifically, a cycle for updating the CIO value is set as the CIO value update cycle (step S401). For example, 1 second, which is a time threshold for determining the cell stay time as a short time when searching for communication history information, is set as the time when the cell stay time is determined as a short time (step S402).

  Also, whether or not automatic updating of the CIO value is validated is set in the automatic setting possibility flag of the CIO value (step S403). Here, automatic updating is disabled. Thereafter, a range of weight values for weighting the ratio of short-term stay calls to the number of handover calls is arbitrarily set (step S404), and an arbitrary range of short-term stay calls is set for each weight value (step S405). ).

  Next, the communication carrier sets information used for the CIO value automatic update process in the eNB information holding units 201 to 204 of the eNBs 11 to 14. That is, in the communication history information transmission cycle, a cycle in which the eNBs 11 to 14 transmit communication history information (UE History Information) to the OMC 1 is set. Here, the UE History Information transmission period to be set is transmitted from OMC1 and OMC2 to eNBs 11 to 14 (step S406), and each of eNBs 11 to 14 sets (step S407).

  FIG. 5 is an operation sequence diagram illustrating the operation of the mobile radio communication system 10 according to the first embodiment of the present invention. Here, the eNBs 11 to 14 accumulate communication history information, and OMC 1 and 2 perform handover traffic. The flow of operations until information is displayed is shown.

  Referring to FIG. 5, each time the call is released, the eNBs 11 to 14 accumulate the communication history information (UE History Information) of the UE 21 (step S501). The communication history information accumulated here is transmitted to the OMCs 1 and 2 when the communication history information transmission cycle set by the maintenance person has been reached (step S502).

  The OMCs 1 and 2 count the number of handover calls to adjacent cells from the received communication history information (step S503). In addition, OMC 1 and 2 refer to the cell stay time information set in the communication history information, and when handing over in a time shorter than the time determined by the maintenance person as a short time, the cell stay time is set to the adjacent cell. The number of short-term stay calls is counted (step S504).

  In the above-described processing, when the history information of the cells managed by the other OMC 1 (2) is included in the communication history information, a CIO value update request is transmitted to the other OMC 2 (1) (step S505). When a CIO value update request is received from another OMC1 (2), the OMC2 (1) adds to the number of handover calls and the number of short-term stay calls calculated from the communication history information received by the own OMC1 (2) (step S506). ).

  Thereafter, the OMC 1 and 2 receive the handover traffic information display command from the maintenance person as a trigger, and the OMC 1 and 2 display a monitor (not shown) that the OMC 1 and 2 have as their handover traffic information the number of handover calls counted previously and the number of short-term stay calls. The maintenance person is notified by displaying it in the figure (step S507). At this time, the handover traffic information to be notified to the maintenance person may be only the number of short stay calls and the number of handover calls, or may be notified by obtaining the ratio of the number of short stay calls to the number of handover calls.

(Effects of the first embodiment)
In the wireless communication system 10 according to the first embodiment of the present invention, the CIO value setting management devices (OMC 1 and 2) calculate the number of short-term stay cell calls using communication history information (UE History Information). By notifying the maintenance person as handover traffic information information for calculating the CIO value for reducing the handover via the short-term stay cell, the maintenance person can perform an actual operation based on the notified handover traffic information. The CIO value can be calculated based on the operation.

(Second Embodiment)
Next, a second embodiment of the present invention will be described.

  In the mobile radio communication system 10 according to the first embodiment of the present invention described above, information for calculating the CIO value for reducing the handover via the short stay cell is notified to the maintenance person as the handover traffic information, and the maintenance is performed. In the second embodiment described below, the CIO setting management device (OMC1, 2) calculates the CIO value that reduces the handover via the short stay cell. By automatically setting the eNBs 11 to 14, maintenance personnel need not be involved. Details will be described below.

(Configuration of Second Embodiment)
In the second embodiment of the present invention described below, the configuration shown in FIGS. 1 to 3 is used as in the first embodiment, and the preprocessing shown in FIG. 4 is performed. I will do it. However, since the CIO value automatic update process is added to the controllers 100 and 103 of the OMCs 1 and 2 here, the following will focus on this CIO value automatic update process and refer to FIGS. 6 to 8. explain.

  Here, the control units 100 and 103 calculate the ratio of the number of short-term stay calls to the number of handover calls to adjacent cells counted by referring to communication history information (UE History Information: UE cell stay time information). The ratio of the number of short-term stay calls occupying the number of short-term stay calls in advance is weighted by using a weight value obtained by weighting every continuous range and added to the CIO value before update. Functions as a control means for calculating a correction value to be corrected.

  In addition, the control units 100 and 103 calculate a correction value to be added to the CIO value before update by using the above-described weight value and an average value obtained by dividing the sum of the weight values of all adjacent cells by the number of all adjacent cells. Then, the CIO value before update of each cell is read from the eNBs 11 and 12, and the CIO value updated from the correction value is calculated and transmitted to the eNBs 11 and 12. Details will be described later.

(Operation of Second Embodiment)
FIG. 6 is an operation sequence diagram showing the CIO value automatic update processing operation of the mobile radio communication system 10 according to the second embodiment of the present invention. The processing procedure of the CIO value automatic update processing executed after the number is searched is shown. Hereinafter, the processing operation of the control unit 100 of the OMC 1 will be described, but the same processing operation is performed in the control unit 103 of the OMC 2.

  Referring to FIG. 6, when the maintainer has previously enabled or disables the automatic setting of the CIO value, the control unit 100 of the OMC 1 first calculates the ratio of the number of short-term stay calls to the number of handover calls to adjacent cells. (Step S601). Next, using the weight value set by the communication carrier, the ratio of the short-term stay calls to the neighboring cell calculated in step S601 is weighted (step S602).

Thereafter, the control unit 100 calculates an average value of the weight values for the adjacent cells, and calculates a correction value of the CIO value using the following arithmetic expression (1) (step S603).
Correction value = (Average value of weight value−Weight value) × Minimum change unit of CIO value (1)

  Here, the correction value indicates a value to be added to the CIO value before update. The CIO value to be updated is obtained by adding a correction value to the CIO value before update. The average value of the weight values is a value obtained by dividing the sum of the weight values of all adjacent cells by the number of all adjacent cells, and is used to suppress the occurrence of large CIO value fluctuations in automatic setting of the CIO values. Note that the control units 100 and 103 of the OMCs 1 and 2 calculate the correction value of the CIO value by always setting the weight value of the cell holding the CIO value to be updated (source cell to the adjacent cell) to 0.

  Next, the control unit 100 reads the correction values obtained by the arithmetic expression (1) from the eNBs 11 to 14 (step S604), and calculates the CIO value to be updated by adding to the CIO value before the update (step S605). Then, the corrected CIO value is transmitted to the eNBs 11 to 14 (step S606). As a result, the control units 110 to 140 of the eNBs 11 to 14 can update the CIO value so that the number of handovers that pass through the short-term stay cell decreases (step S607). In addition, the CIO value automatic update process described above is executed a plurality of times, so that the CIO value is corrected to a smaller number of short-term stay calls.

  7 and 8 are diagrams for explaining specific operations of the mobile radio communication system according to the second embodiment of the present invention, and supplement the processing contents of steps S601 to S603 in the flowchart of FIG. It is shown in the meaning. FIG. 7 shows an example of cell arrangement, and FIG. 8 shows an example of a specific data structure set in the OMC information holding unit 101 during the CIO value automatic update process.

  Hereinafter, in the flowchart of FIG. 6, the specific processing contents of the processing of calculating the correction value of the CIO value (step S <b> 603) by weighting the ratio of the short-term stay calls to the adjacent cells (steps S <b> 601 and S <b> 602) This will be described with reference to FIG.

  Referring to FIG. 7, if a specific cell 37 is assigned the CIO value of its own cell 37 and neighboring cells 38 to 43 (FIG. 8), OMC 1 searches for UE communication history information. As a result, the ratio of the short-term stay calls from the own cell 37 to the adjacent cells 38 to 43 is 35% for the adjacent cell 38, 40% for the adjacent cell 39, 35% for the adjacent cell 40, 15% for the adjacent cell 41, Assume that the adjacent cell 42 is calculated to be 20% and the adjacent cell 43 is calculated to be 5% (step S601 in FIG. 6).

  As shown in FIG. 8, the weight values for calculating the correction value of the CIO value held in the maintenance person setting information holding unit 111 of the OME information holding unit 101 of OME1 are as follows in step S602 of FIG. It is calculated as follows.

  That is, when the ratio of the number of short-term stay calls is 0 to 14%, the weight value is 0, when the rate is 15 to 29%, the weight value is 1, and when the ratio is 30 to 44%, the weight value is 2 and 45 to 59%. The weight value is 3, the weight value is 4 for 60 to 74%, the weight is 5 for 75 to 89%, the weight value 6 is set for 90 to 100%, and the short term is set by the maintenance person. The weight value of the neighbor cell 38 where the ratio of stay calls is 35% is 2, the weight value of the neighbor cell 39 where the ratio of short stay calls is 40% is 2, and the ratio of short stay calls is 35%. The weight value of the neighbor cell 40 is 2, the weight value of the neighbor cell 41 whose ratio of short-term stay calls is 15% is 1, the weight value of the neighbor cell 42 whose ratio of short-term stay calls is 20% is 1, and short-term The weight value of the adjacent cell 43 in which the ratio of the number of stay calls is 5% is zero. The weight value of its own cell 37 is always 0.

  Next, in step S603 in FIG. 6, the control unit 100 calculates the correction value for the CIO value by the above-described arithmetic expression (1). At this time, it is assumed that the minimum change unit of the CIO value is 1.

  Specifically, the average value of the weight is (2 (weight value of the neighbor cell 38) +2 (weight value of the neighbor cell 39) +2 (weight value of the neighbor cell 40) + (weight value of the neighbor cell 41) +1 (neighbor cell) 42 weight value) +0 (weight value of adjacent cell 43)) / 6 (number of adjacent cells) ≈1. Therefore, the correction value of the CIO value of the adjacent cells 41 and 42 with the weight value 1 is 0. Further, the correction value of the CIO value of the adjacent cells 38 to 40 having the weight value of 2 is -1. Further, the correction value of the CIO value of the adjacent cell 43 with the weight value set to 0 is 1. Further, since the weight value of its own cell 37 is 0, the correction value of the CIO value of its own cell 37 is 1.

  The correction value of the CIO value calculated by the above-described process is added to the pre-update CIO value read in step S604 in FIG. 6 to calculate an updated CIO value (step S605).

(Effects of the second embodiment)
In the mobile radio communication system 10 according to the above-described second embodiment, the CIO setting management device (OMC 1, 2) refers to communication history information (UE History Information: UE cell residence time information) to the adjacent cell. Calculate the ratio of short-term stay calls in the number of handover calls, and calculate the ratio of short-term stay calls calculated using weight values weighted for each continuous range in advance. Since the weighting ratio is calculated and the correction value to be added to the CIO value before update is calculated and transmitted to the eNBs 11 and 12, the CIO value calculated based on the actual operation state can be set in the eNBs 11 to 14, for example, When the operational status changes due to factors such as new settings, abolition of eNBs 11-14, construction of buildings, opening of roads / trains, etc., CIO values are automatically updated without the intervention of maintenance personnel Is possible. For this reason, the burden on the carrier side is reduced.

  Note that according to the first and second embodiments of the present invention described above, only the mobile radio communication system 10 using LTE is illustrated as the mobile radio communication system, but the mobile radio communication system is not limited to LTE, and the eNB 11 The communication history information accumulated in -14 can be collected, and can be applied to all mobile radio communication systems using other communication protocols that require updating of CIO values.

  As described above, the CIO value setting management device (OMC1, 2) of the present invention refers to the cell stay time information included in the communication history information transmitted from the base stations (eNBs 11 to 14), and the cell stay time. By searching for short-term staying cells shorter than the specified value and generating and outputting traffic information that can update the CIO value that reduces the number of handover calls via the short-term staying cells, hand-over statistical information in actual operation regardless of running tests Since the CIO value can be set based on the cost, the cost can be reduced. Also, setting the automatically calculated CIO value in the base station contributes to reducing the burden on the telecommunications carrier side.

  1 may be realized entirely by software, or at least a part thereof may be realized by hardware. For example, the control unit 100 refers to cell stay time information included in communication history information transmitted from the base station, searches for a short stay cell whose cell stay time is shorter than a specified value, and performs handover via the short stay cell. Data processing for generating and outputting traffic information capable of updating the CIO value for reducing the number of calls may be realized on a computer by one or a plurality of programs, and at least a part thereof may be realized by hardware. Good.

  In addition, the CIO value setting method using the cell stay time information of the mobile station according to the present invention is, for example, as shown in FIG. 1, as shown in FIG. eNBs 11 to 14) and one or more base stations connected to each other, and a CIO setting management device (OMC 12) capable of message communication with each other. A method for setting a CIO value using time information, for example, as shown in FIG. 5, the base station accumulates communication history information of the mobile station every time a call is released, and the accumulated A first step (S501, S502) of reading communication history information for each preset transmission cycle and transmitting the communication history information to the connected CIO setting management device; and The cell stay time information included in the communication history information transmitted and received from the mobile station is referred to, a short stay cell that is handed over in a time shorter than a specified value is searched, and the number of handover calls via the short stay cell is reduced. A second step (S503 to S507) of generating traffic information capable of calculating a radio quality correction value and transmitting the traffic information to the base station.

  According to the CIO value setting method using the cell stay time information of the mobile station of the present invention, it is possible to set the CIO value based on the handover statistical information in actual operation without performing a running test or the like. Maintenance costs can be reduced. In addition, setting the automatically calculated CIO value in the base station makes it possible to update the CIO value without the intervention of a driver, which can contribute to reducing the burden on the telecommunications carrier side.

  Although the present invention has been described with reference to the preferred embodiments and examples, the present invention is not necessarily limited to the above-described embodiments and examples, and various modifications may be made within the scope of the technical idea. Can be implemented.

1, 2: CIO value setting management device (OMC)
10: Mobile radio communication system 11-14: Base station (eNB)
21: Mobile station (UE)
31-43: Cell 100, 103: Control unit 101, 102: OMC information holding unit 111: Maintenance person setting information holding unit 112: CIO value update related information holding unit 201-204: eNB information holding unit 211: Maintenance person setting Information holding unit 212: Communication history information holding unit

Claims (10)

A CIO setting management device of a base station to which a plurality of mobile stations are wirelessly connected,
CIO that refers to cell stay time information included in communication history information transmitted from the base station, searches for short stay cells whose cell stay time is shorter than a specified value, and reduces the number of handover calls via the short stay cells a control means to generate and output an updatable traffic information values,
The control means includes
Calculate the ratio of short-term stay calls to the number of handover calls to neighboring cells counted by referring to the communication history information, and pre-determine the ratio of short-term stay calls to the number of handover calls. A CIO setting management apparatus characterized in that a weight value weighted for each range is used to weight the ratio of the calculated number of short-term stay calls, and a correction value to be added to the CIO value before update is calculated . The control means includes
A correction value to be added to the CIO value before update is calculated from the weight value and an average value obtained by dividing the sum of the weight values of all adjacent cells by the number of all adjacent cells, and each cell is updated from the base station. The CIO setting management apparatus according to claim 1, wherein a previous CIO value is read, a CIO value updated from the correction value is calculated and transmitted to a base station . A mobile radio communication system comprising one or more base stations to which a plurality of mobile stations are wirelessly connected, and a CIO setting management device connected to each of the one or more base stations and capable of message communication with each other. And
The base station
Each time a call is released, communication history information of the mobile station is accumulated, and the accumulated communication history information is read at a preset transmission cycle and transmitted to the connected CIO setting management device. ,
The CIO setting management device
The number of handover calls via the short stay cell is searched by referring to cell stay time information included in the communication history information transmitted and received from the base station, searching for a short stay cell that is handed over in a time shorter than a specified value. Control means for generating traffic information capable of calculating a radio quality correction value for reducing the frequency and transmitting the traffic information to the base station,
The control means includes
Calculate the ratio of short-term stay calls to the number of handover calls to neighboring cells counted by referring to the communication history information, and pre-determine the ratio of short-term stay calls to the number of handover calls. The weight value weighted for each range is used to weight the calculated percentage of short-term stay calls, and a correction value to be added to the CIO value before update is calculated.
A mobile radio communication system . The CIO setting management device
When the history of the cells managed by the other CIO setting management device is included in the communication history information referred to, the wireless quality correction value update request is transmitted to the other CIO setting management device.
When a CIO value update request is received from the other CIO setting management device, it is added to the number of handover calls and the number of short-term stay calls retrieved from the communication history information received by the own CIO setting management device, and the handover traffic information output 4. The mobile radio communication system according to claim 3, wherein the mobile radio communication system according to claim 3, wherein the number of handover calls and the number of short-term stay calls, or the ratio of the number of short-term stay calls to the number of handover calls is output after a request arrives . The CIO setting management device
Calculating a correction value to be added to the wireless quality correction value before update by the weight value and an average value obtained by dividing the sum of the weight values of all adjacent cells by the number of all adjacent cells;
Read the CIO value before update of each cell from the base station, calculate the updated CIO value from the calculated correction value, and transmit to the base station,
The mobile radio communication system according to claim 3 or 4, characterized by the above . Used in a wireless communication system including one or more base stations to which a plurality of mobile stations are wirelessly connected, and a CIO setting management device that is connected to each of the one or more base stations and that can communicate with each other. , A CIO value setting method using cell stay time information of a mobile station,
The base station accumulates communication history information of the mobile station every time a call is released, reads the accumulated communication history information at a preset transmission cycle, and transmits it to the connected CIO setting management device A first step to:
The CIO setting management device refers to cell stay time information included in the communication history information transmitted and received from the base station, searches for a short stay cell that is handed over in a time shorter than a specified value, and A second step of generating traffic information capable of calculating a radio quality correction value for reducing the number of handover calls via the staying cell and transmitting the traffic information to the base station;
The second step includes
Calculate the ratio of short-term stay calls to the number of handover calls to neighboring cells counted by referring to the communication history information, and pre-determine the ratio of short-term stay calls to the number of handover calls. A sub-step of calculating a correction value to be added to the pre-update CIO value by weighting the ratio of the calculated short-term stay call number using a weight value weighted for each range
A method for setting a CIO value using cell residence time information of a mobile station . The second step includes
A sub-step of transmitting an update request for the wireless quality correction value to the other CIO setting management device if the history of cells managed by the other CIO setting management device is included in the referred communication history information;
When the CIO value update request is received from the other CIO setting management device, it is added to the number of handover calls and the number of short-term stay calls retrieved from the communication history information received by the own CIO setting management device, and the handover traffic information output Waiting for the arrival of a request, the sub-step of outputting the number of handover calls and the number of short-term stay calls, or the ratio of the number of short-term stay calls to the number of handover calls;
The method of setting a CIO value using cell stay time information of a mobile station according to claim 6 . The second step includes
A sub-step of calculating a correction value to be added to the wireless quality correction value before update by the weight value and an average value obtained by dividing the sum of the weight values of all adjacent cells by the number of all adjacent cells;
A sub-step of reading a CIO value before update of each cell from the base station, calculating a CIO value updated from the calculated correction value, and transmitting the CIO value to the base station;
The CIO value setting method using the cell stay time information of the mobile station according to claim 6 or 7, further comprising: A CIO value setting management program of a CIO setting management device of a base station that is executed on a computer and to which a plurality of mobile stations are wirelessly connected,
In the computer,
A search process for referring to cell stay time information included in communication history information transmitted from the base station and searching for a short stay cell whose cell stay time is shorter than a specified value;
An output process for generating and outputting traffic information capable of updating a CIO value for reducing the number of handover calls via the short-stay cell;
A ratio calculation process for calculating the ratio of short-term stay calls to the number of handover calls to neighboring cells counted by referring to the communication history information;
The ratio of the number of short-term stay calls occupying the number of short-term stay calls in advance is weighted by using a weight value obtained by weighting each predetermined continuous range and added to the CIO value before update. Correction value calculation processing for calculating a correction value to be performed;
A CIO value setting management program characterized in that The correction value calculation process includes:
A correction value to be added to the CIO value before update is calculated from the weight value and an average value obtained by dividing the sum of the weight values of all adjacent cells by the number of all adjacent cells, and each cell is updated from the base station. Reading a previous CIO value, calculating a CIO value updated from the correction value and transmitting it to the base station;
The CIO setting management program according to claim 9 .

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