Method and Apparatus for Optimizing Neighbor List Automatically in Synchronous Cdma Network

• US 20080225797A1
• Filed: 08/28/2006
• Published: 09/18/2008
• Est. Priority Date: 08/29/2005
• Status: Active Grant

• Current Assignee: KT Corporation
• Original Assignee: KT Corporation
• Inventors: Kim, Shin-Jae
• Granted Patent: US 8,054,803 B2
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04W 36/0061 of neighbour cell information
• CPC Class Codes: H04W 36/00835 Determination of neighbour cell lists

Abstract

A method for automatically optimizing a neighbor list for processing handover in a synchronous CDMA (Code Division Multiple Access) network includes the steps of: collecting neighbor list data, call fault data, handover statistical data, base station location data and PN information data of each base station sector in a nationwide network; extracting all target sectors available for handover by analyzing the collected data; endowing a weighting factor to the extracted target sectors according to importance and then sorting the target sectors according to calculated results so as to determine priorities; and subsequently inputting the target sector information to the neighbor list according to the priorities.

Claims

1. A method for automatically optimizing a neighbor list for processing handover in a synchronous CDMA (Code Division Multiple Access) network, comprising:

(a) collecting neighbor list data, call fault data, handover statistical data, base station location data and PN information data of each base station sector in a nationwide network;

(b) extracting all target sectors available for handover by analyzing the collected data;

(c) endowing a weighting factor to the extracted target sectors according to importance and then sorting calculated results so as to determine priorities; and

(d) subsequently inputting the target sector information to the neighbor list according to the priorities.

2. The method for automatically optimizing a neighbor list according to claim 1, wherein the step (c) includes:

calculating the number of intermediate base stations positioned within a distance between a source base station and a target base station and existing within a threshold angle toward the target base station based on the source base station and a threshold angle toward the source base station based on the target base station, as for the extracted target sectors; and

determining priorities of the target sectors by sorting such that a target base station with a relatively lower index, calculated including the number of intermediate base stations and the distance, has a higher priority.

3. The method for automatically optimizing a neighbor list according to claim 1 or 2, in the step (b), further comprising:

verifying contents of the neighbor list by comparing the neighbor list data with the base station location data and the PN information data.

4. The method for automatically optimizing a neighbor list according to claim 3, wherein the base station location data and the PN information data are compared with system ID (SIS), network ID (NID), base station controller (BSC), base station (BTS) and sector PN (Pseudo Noise) in the neighbor list for the verification.

5. The method for automatically optimizing a neighbor list according to claim 1 or 2,

wherein, in the step (c), the target sector information is classified into a type that a target sector exists in the neighbor list and exists in the handover statistics, a type that a target sector does not exist in the neighbor list but exists in the handover statistics, a type that a target sector exists in the neighbor list but does not exist in the handover statistics, a type that a target sector does not exist in the neighbor list and a handover failure PN occurs, and a type that a target sector exists in the neighbor list but handover is failed, and then a weighting factor is endowed thereto depending on importance of each type.

6. The method for automatically optimizing a neighbor list according to claim 5, wherein, in the step (c), SID, NID, BSC and BTS information of each classified target sector is utilized to check location of the target sector.

7. The method for automatically optimizing a neighbor list according to claim 5, wherein a weighting factor is endowed to a handover trial frequency for the target sector of each type.

8. The method for automatically optimizing a neighbor list according to claim 7, wherein the handover trial frequency information is obtained as a trial frequency of the handover statistics of each sector, or by extracting candidate sets included in the call fault data and then counting the candidate sets.

9. An apparatus for automatically optimizing a neighbor list for processing handover in a synchronous CDMA network, comprising:

a data collecting unit for collecting neighbor list data, call fault data, handover statistical data, base station location data and PN information data of each base station sector in a nationwide network;

a data analyzing unit for analyzing the collected data to extract all target sectors available for handover;

a data sorting processing unit for endowing a weighing factor to the extracted target sector information depending on importance and then sorting the calculated results in order so as to determine priorities thereof; and

a list input unit for subsequently inputting the target sector information to the neighbor list according to the priorities.

10. The apparatus for automatically optimizing a neighbor list according to claim 9, further comprising:

a base station searching unit for calculating the number of intermediate base stations, which are positioned within a distance between a source base station and a target base station and exist within a threshold angle toward the target base station based on the source base station and within a threshold angle toward the source base station based on the target base station, for the extracted target sectors,

wherein the data sorting processing unit determines priorities of the target sectors by sorting such that a target base station with a relatively lower index, calculated including the number of intermediate base stations and the distance, has a higher priority.

11. The apparatus for automatically optimizing a neighbor list according to claim 9 or 10, further comprising:

a list verifying unit for verifying contents of the neighbor list by comparing the neighbor list data with the base station location data and the PN information data.

12. The apparatus for automatically optimizing a neighbor list according to claim 11, wherein the list verifying unit verifies the contents by comparing SID, NID, BSC, BTS and sector PN data in the neighbor list with the base station location data and the PN information data.

13. The apparatus for automatically optimizing a neighbor list according to claim 9 or 10,

wherein the data sorting processing unit classifies the target sector information into a type that a target sector exists in the neighbor list and exists in the handover statistics, a type that a target sector does not exist in the neighbor list but exists in the handover statistics, a type that a target sector exists in the neighbor list but does not exist in the handover statistics, a type that a target sector does not exist in the neighbor list and a handover failure PN occurs, and a type that a target sector exists in the neighbor list but handover is failed, and then endows a weighting factor depending on importance of each type.

14. The apparatus for automatically optimizing a neighbor list according to claim 13, wherein the data sorting processing unit endows a weighting factor to a handover trial frequency of the target sector of each type.

15. The apparatus for automatically optimizing a neighbor list according to claim 14, wherein the handover trial frequency information is obtained as a trial frequency of the handover statistics of each sector, or by extracting candidate sets included in the call fault data and then counting the candidate sets.