CN104581778A - Identification method of serving cell missing configuration neighbor cell in LTE system - Google Patents

Abstract

The invention discloses a method for identifying a missed neighbor cell of a service cell in a LTE (long term evolution) system. The method comprises the following steps: for each MR (measurement report) reported to UE (user equipment), recording the MR if the MR contains a PCI (physical-layer cell identity) which is not configured in a neighbor cell table of the service cell; searching for a target cell corresponding to the PCI in the neighbor cell table of all neighbor cells of the service cell when the MR accumulated in a same scene achieves a recording limit value, if the target cell is found, backfilling a CI (cell identity) of the target cell to the CI of the missed neighbor cell, if the target cell is not found, taking the neighbor cell of these neighbor cells as the service cell, looking for the neighbor cell table of these neighbor cells from the next-stage neighbor cells to judge whether the corresponding target cell is contained in the neighbor cell table or not, if the target cell is found, backfilling the CI of the target cell to the CI of the missed neighbor cell and if the target cell is not found, searching the CI of the PCI in the whole network range, and backfilling the CI of the nearest target cell to the CI of the non-configured neighbor cell according to the principle of proximity. The method disclosed by the invention can accurately identify the unknown neighbor cell.

Description

Identification method of serving cell missing configuration neighbor cell in LTE system

technical field

The invention relates to the field of radio communication, in particular to a method for identifying adjacent cells that are missing from a serving cell in an LTE system.

Background technique

The handover measurement of LTE has an obvious feature, that is, its measurement is based on the frequency point rather than the neighbor cell list. The UE measures the cell using the frequency point according to the frequency point indicated by the measurement configuration, and then the high layer of the UE processes the measurement result, obtains a handover candidate list and sends it to the network, and the network selects a cell (according to the neighbor cell list) to initiate handover. However, the neighbor cells not configured in the neighbor cell list (frequency point + PCI, PCI is the physical cell ID physical layer cell identification number) will become the neighbor cells that the system omits to configure. Form a switch.

The SON (Self Organizing Network, self-organizing network) function is a concept proposed by operators, mainly to realize the wireless network self-organization function. Automatic Neighbor Ralation (ANR) is one of the key technologies of SON, which can realize the self-configuration and liberalization of neighbor relationship, and is an automatic neighbor optimization function provided by equipment manufacturers. However, in the data processing output results of the LTE live network, many adjacent cells that must be added are found to be omitted. After verification, they are indeed necessary adjacent cells. The results fully show that the reliability of ANR is not high.

Contents of the invention

In order to solve the above problems, the purpose of the present invention is to provide a method for identifying neighboring cells that are missing from serving cells in an LTE system, so as to accurately identify unknown neighboring cells.

The technical scheme that the present invention solves its problem adopts is:

A method for identifying neighboring cells that are missing from a serving cell in an LTE system includes:

For the MR reported by the UE, when the MR contains PCIs that are not configured in the neighboring cell table of the serving cell, record the MR; , then:

(1) Search for the target cell corresponding to the PCI from the neighboring cell tables of all neighboring cells of the serving cell, if found, backfill the CI corresponding to the target cell to the CI of the missing configuration neighboring cell, and end the search;

(2) If not found, use the neighboring cells of these neighboring cells as the serving cell, and find out whether the neighboring cell tables of these neighboring cells contain the target cell corresponding to the PCI from the next-level neighboring cells, and if found, set the target cell The CI corresponding to the cell is backfilled to the CI of the missing configuration neighbor cell, and the search is ended;

(3) If it is not found, use the sector latitude and longitude and azimuth information to query the CI of the PCI in the entire network, and based on the principle of proximity, backfill the CI of the nearest target cell as the cell identification number of an unconfigured neighboring cell.

Further, the MR reported by the UE is triggered periodically or by an event.

Further, in the step (2), while backfilling the CI corresponding to the target cell to the CI of the missing configuration neighbor cell, add the record of the serving cell and the missing configuration neighbor cell to the output table of the LTE system suggestion to add the neighbor cell .

Further, the principle of the nearest selection mentioned in the step (3) is:

Select the CI of the target cell closest to the serving cell and with the highest azimuth probability as the cell identification number of the unconfigured neighbor cell.

Further, the method also includes:

For the output table suggested to add adjacent cells, calculate the actual distance between the serving cell and the missing configured adjacent cell sectors according to the longitude and latitude of the sectors in the basic database of base station information, and use the base station information of station height and azimuth to calculate the two Covering the area of the overlapping area between them, a correlation coefficient that is inversely proportional to the distance and proportional to the overlapping area is obtained, and the threshold value is set according to this correlation coefficient.

The beneficial effects of the present invention are:

The present invention adopts a method for identifying neighboring cells with missing configuration in the serving cell in the LTE system, and outputs the correlation between the serving cell and the neighboring cells with missing configuration through the measurement report data of a large number of mobile phone users in the LTE system, after screening and filtering operations, The necessity of adding these unconfigured adjacent cells can be quickly and accurately located, and when adding, the cell identification number (CELLID) of the unconfigured adjacent cells of the serving cell can be accurately determined.

Description of drawings

The present invention will be further described below in conjunction with accompanying drawing and example.

Fig. 1 is a schematic flow sheet of the method of the present invention;

Fig. 2 is a schematic diagram of serving cell configuration according to the present invention.

Detailed ways

Example 1:

In the present invention, PCI, CI and MR are common terms in LTE technology. PCI (physical-layer Cell identity) is composed of a primary synchronization signal (PSS) and a secondary synchronization signal (SSS), which can be obtained through simple calculations. The formula is as follows: PCI=PSS+3*SSS, where the value of PSS is 0...2 (actually 3 different PSS sequences), the value of SSS is 0...167 (actually 168 different SSS sequences), Using the above formula, the range of PCI can be obtained from 0...503, so there are 504 PCIs in the physical layer. CI (Cell Identity) uniquely identifies a cell and cannot be repeated in the network. MR is a measurement report (Measurement Report), which is a method of collecting network optimization measurement data using ordinary mobile phones and data cards.

An obvious feature of LTE handover measurement is that its measurement is based on frequency points rather than neighbor cell lists. The UE measures the cell using the frequency point according to the frequency point indicated by the measurement configuration, and then the high layer of the UE processes the measurement result, obtains a handover candidate list and sends it to the network, and the network selects a cell to initiate handover (according to the neighbor cell list). If an MR reported by the UE contains a PCI that is not configured in the neighboring cell table of the serving cell, the handover process cannot occur. For this reason, the present invention records this report, and when the number of MR measurement reports in this type of scene accumulates to meet the set threshold, then identify the suspected PCI with no adjacent cell configured.

With reference to shown in Fig. 1, the present invention provides a kind of identification method of serving cell missing configuration neighboring cell in LTE system, comprising:

For the MR reported by the UE, when the MR contains PCIs that are not configured in the neighboring cell table of the serving cell, record the MR; , then:

(1) Search for the target cell corresponding to the PCI from the neighboring cell tables of all neighboring cells of the serving cell, if found, backfill the CI corresponding to the target cell to the CI of the missing configuration neighboring cell, and end the search;

(2) If not found, use the neighboring cells of these neighboring cells as the serving cell, and find out whether the neighboring cell tables of these neighboring cells contain the target cell corresponding to the PCI from the next-level neighboring cells, and if found, set the target cell The CI corresponding to the cell is backfilled to the CI of the missing configuration neighbor cell, and the search is ended;

(3) If it is not found, use the sector latitude and longitude and azimuth information to query the CI of the PCI in the entire network, and based on the principle of proximity, backfill the CI of the nearest target cell as the cell identification number of an unconfigured neighboring cell.

Wherein, the MR reported by the UE is triggered periodically or by an event.

In the step (2), while backfilling the CI corresponding to the target cell to the CI of the missing configuration neighbor cell, adding the record of the serving cell and the missing configuration neighbor cell to the output table of the LTE system suggestion to add the neighbor cell. For the output table suggested to add adjacent cells, calculate the actual distance between the serving cell and the missing configured adjacent cell sectors according to the longitude and latitude of the sectors in the basic database of base station information, and use the base station information of station height and azimuth to calculate the two Covering the area of the overlapping area between them, a correlation coefficient that is inversely proportional to the distance and proportional to the overlapping area is obtained, and the threshold value is set according to this correlation coefficient.

The principle of nearest selection mentioned in step (3) refers to:

Select the CI of the target cell closest to the serving cell and with the highest azimuth probability as the cell identification number of the unconfigured neighbor cell.

Example 2:

In order to specifically describe the present invention, referring to FIG. 2 , the present invention uses specific examples to illustrate the above-mentioned method in detail. In Figure 2, the PCI of the S serving cell is 6, and the cell database is configured with 4 adjacent cells N1-N4, and their PCIs are 5, 8, 7, and 11 respectively. When the fourth adjacent cell N4 is used as the serving cell, only A neighboring cell N41 is configured with PCI 12. When N41 is used as the serving cell, only one neighboring cell N411 and PCI 10 are configured. When N411 and PCI 10 are used as the serving cell, a neighboring cell Nx is also configured, and Nx is the leaking cell. Configure adjacent cells, PCI is 4. With the continuous expansion of the system scale and the negligence of the planners, it is suspected that Nx is missing to configure adjacent cells.

The measurement report of the mobile phone can be periodic or event-triggered. If the UE reports a measurement report containing unconfigured PCI 4 in the neighbor table of the serving cell, the EARFCN is 38350 cells, even if the measured value is higher than Handover is impossible due to the set threshold, but this measurement report will be recorded by relevant statistics. When the cumulative number of measurement reports in the same scene exceeds the threshold preset by the algorithm, the PCI suspected of not configuring adjacent cells needs to be identified, the identification method is as follows:

First look up the 4 adjacent cells configured by the S serving cell, that is, the adjacent cell table with PCIs 5, 8, 7, and 11, and EARFCN (frequency point) 38350. In the figure, N1-N3 are not configured with adjacent cells, so you only need to Search the neighbor cell table of N4 to see if the target neighbor cell whose PCI is 4 and EARFCN is 38350 can be found, and if it can be found, backfill the CI of the target cell as the missing configuration neighbor cell CI;

If the target cell is not found in the adjacent cell table at this level, use N41 as the serving cell, and check whether there is a cell with PCI 4 and EARFCN 38350 in the adjacent cell table, and find that Nx is configured in the adjacent cell table As its neighbor cell, its PCI is 4, and its EARFCN is 38350. Backfill the CI of the target cell Nx as the CI of the suspected missing configuration neighbor cell of the S serving cell, and add this in the output table of the system suggestion to add neighbor cells A record of the serving cell and the suspected missing configuration neighbor cell;

If it is not found at this level, the search process ends here. Use the longitude, latitude and azimuth information of the sector to query the CI of this PCI in the entire network. According to the principle of nearest selection, backfill the CI of the target cell that is closest to the serving cell S and has the highest azimuth probability as the identification of a cell that has no neighbors configured. Number.

When post-processing the output table that suggests adding neighbors, for each output suspected missing configuration neighbor record, calculate the actual distance between sectors according to the longitude and latitude of the sector in the basic database of base station information, and use the station height and azimuth Angle and other base station information, calculate the area of coverage overlapping area (Tyson polygon) between the two, get the correlation coefficient that is inversely proportional to the distance and proportional to the overlapping area, set the threshold value according to actual experience, and commission in the actual live network A reasonable threshold is given, so that the suggestion provided to the user can be added to the neighbor list without manual verification, and it can be automatically output according to the system-customized time every day. The live network practice of the above algorithm proves that the optimization module implemented by the above algorithm can save a lot of labor costs, improve optimization efficiency, and improve network performance.

The above descriptions are only preferred embodiments of the present invention, and the present invention is not limited to the above-mentioned embodiments, as long as they achieve the technical effects of the present invention by the same means, they should all belong to the protection scope of the present invention.

Claims (5)

1. the recognition methods of Serving cell leakage configuring adjacent cell in LTE system, is characterized in that, comprising:

To the MR that UE reports, when this MR includes the PCI do not configured in the table of this adjacent area, Serving cell, then record this MR; When the MR including the PCI do not configured in the table of this adjacent area, Serving cell adds up to reach record limit value, then:

(1) from the adjacent cell table of all adjacent cells of this Serving cell, search the Target cell corresponding with this PCI, if find, then CI corresponding for this Target cell is backfilled to this leakage configuration adjacent cell CI, and terminates to search;

(2) if do not find, then with the adjacent cell of these adjacent cells for Serving cell, whether the adjacent cell table finding these adjacent cells from next stage adjacent area comprises the Target cell corresponding with this PCI, if find, then CI corresponding for this Target cell is backfilled to this leakage configuration adjacent cell CI, and terminates to search;

(3) if do not find, then utilize sector longitude and latitude and azimuth information, inquire about the CI of this PCI in network-wide basis, according to the principle selected nearby, the CI backfilling nearest Target cell is the cell identification number of non-configuring adjacent cell.

2. recognition methods according to claim 1, is characterized in that, the MR that described UE reports is that periodicity or event trigger.

3. recognition methods according to claim 1, it is characterized in that, while CI corresponding for this Target cell being backfilled in described step (2) this leakage configuration adjacent cell CI, adding in the output table of adjacent area in LTE system suggestion and add this Serving cell and the record leaking configuring adjacent cell.

4. recognition methods according to claim 1, is characterized in that, the principle selected nearby described in described step (3) namely:

This Serving cell of chosen distance is nearest, the CI of the Target cell of azimuth maximum probability is the cell identification number of non-configuring adjacent cell.

5. recognition methods according to claim 3, is characterized in that, described method also comprises:

Suggestion is added to the output table of adjacent area, according to longitude, the latitude of the sector in base station information basic database, calculation services community and the actual range leaked between sector, configuring adjacent cell, utilize station height and azimuthal base station information, the area of the covering overlapping area between both calculating, obtain being inversely proportional to distance the coefficient correlation be directly proportional to overlapping area, threshold value is set according to this coefficient correlation.