KR20020023477A - Method for registration automatic of neighbor list in mobile communication system - Google Patents

Abstract

PURPOSE: An automatic registering method for a neighbor list in a mobile communication system is provided to process a smooth hand-off by automatically registering information of an adjacent BTS(Base Transceiver Station) in the neighbor list in the mobile communication system. CONSTITUTION: It is retrieved whether information of the second BTS is registered in a neighbor list of a BSC(Base Station Controller)(ST32). If information of the second BTS is not registered in the neighbor list of the BSC, a pilot offset of the second BTS for checking the neighbor list is transmitted to a BSM(Base Station Manager)(ST33). The BSM receives the pilot offset of the second BTS, and judges whether a pilot offset of the second BTS corresponding to a neighbor list of a PLD(Program Load Data) is registered(ST34). If a BTS requested to the neighbor list is not registered, PLD in which pilot offsets of all BTSs added to the neighbor list is retrieved on the basis of the received pilot offset among the PLD stored in the BSM(ST35). Information of a BTS which is identical to a pilot offset for requesting a hand-off is collected, and collected information is added to the neighbor list of the BSM(ST36). Information of a neighbor list corresponding to the first BTS is transmitted to the BSC, and the BSC deletes the neighbor list to the first BTS stored in the PLD and newly adds the neighbor list received from the BSM(ST37). A hand-off performance message is transmitted to the first BTS(ST38).

Description

Method for registration automatic of neighbor list in mobile communication system

The present invention provides a cellular mobile communication system using a code division multiple access (CDMA) scheme, a personal communication services system (hereinafter referred to as a 'PCS' system), a satellite communication system, and the like. The present invention relates to a method of automatically registering a neighbor list in a mobile communication system. In particular, an operator automatically registers information of a neighbor base station in a neighbor list in a mobile communication system without directly inputting the neighbor list, thereby handling smooth handoff. The present invention relates to a method for automatically registering a neighbor list in a mobile communication system.

In general, a mobile communication system is a system that allows a mobile station to communicate while moving, and its configuration is shown in FIG.

As shown, a mobile station 10 requesting a communication service of a mobile subscriber and receiving a communication service from the mobile communication system; A base station 20 for transmitting and receiving a signal in a wireless area with the mobile station 10; A control station (30) for performing signal processing between the base station (20) and the switching center (40) and controlling the base station (20); It is composed of an exchange station 40 is connected to the control station 30 to perform the exchange connection of the mobile communication network, and connects the mobile communication network and another communication network.

Referring to the operation of such a general mobile communication system, if a mobile subscriber has a mobile station 10 and is in the service area of the base station 20 and requests mobile communication service, the switching center 40 is configured to control the control station 30. Under control, the position of the mobile station 10 is determined, and a mobile communication service is performed according to the request of the mobile station 10.

2 is a diagram of a base station boundary region of a typical mobile communication system.

An area in which a communication service is available at one base station is called a cell, and the cell is defined by the pilot power intensity output from the base station through a pilot channel. Accordingly, whether a mobile station located at a cell boundary belongs to a communication service area of a base station can be detected by detecting the received pilot power strength of the mobile station transmitted to the base station.

When the mobile station 10 is located in the service area of the first base station 21 and is provided with the service of the first base station 21 and moves to belong to the service area of the second base station 22, the mobile station in communication The handoff must be performed so that (10) can continue to communicate. In this case, the hand off is an operation in which a communication service is continuously performed by automatically switching a line when a communicating mobile station moves from one cell to another cell.

3 is a flowchart schematically illustrating a handoff method of a general mobile communication system.

As shown therein, comparing the pilot power strengths of the neighbor base stations received from the mobile stations with the pilot detection thresholds (ST1-ST2); If the comparison result indicates that the pilot power strength of the neighboring base station is greater than or equal to the pilot detection threshold, a step of transmitting a handoff request message (ST3-ST4).

A handoff method of the mobile communication system as described above is as follows.

First, the mobile station 10 searches for the pilot power strength of the first base station 21 while receiving the service of the first base station 21 in the service area of the first base station 21 and sends a signal measurement message to the first base station ( To 21).

Thereafter, the mobile station 10 approaches the handoff area, and the pilot power strength of the second base station 22 is the pilot detection threshold value (cell boundary area with the second base station 22). If greater than the received pilot power strength (threshold threshold required for handoff) at 24, a signal measurement message for handoff to the second base station 22 is transmitted to the base station 21 (ST1). The signal measurement message includes a pilot offset for identifying each base station 21 and 22 and information about pilot power strength.

The first base station 21 then transmits this received signal measurement message to the base station controller, which compares the pilot power strength of the second base station 22 with the pilot detection threshold (ST2). As a result of the comparison, when the pilot power strength of the second base station 22 is larger than the pilot detection threshold value, handoff to the second base station 22 is requested (ST3-ST4).

In this operation, the handoff is performed so that the mobile station 10 can continue to communicate without disconnection even after moving to the service area of the second base station 22.

4 is a schematic diagram of a general PCS system.

As shown, a mobile station 10 requesting a communication service of a mobile subscriber and receiving a communication service from the mobile communication system; A first base station (21) and a second base station (22) for transmitting and receiving signals to and from the mobile station (10); A control station (30) for controlling the base station (30) to perform signal processing between the base stations (21) (22) and the switching center (40); An exchange station (40) connected to the control station (30) to perform an exchange connection of a mobile communication network and to connect the mobile communication network with another communication network; It consists of a control station manager (BSM) 50 which manages the control station 30 and the base stations 21 and 22.

Referring to the operation of the general PCS mobile communication system, when the mobile station 10 establishes a call with the first base station 21 and moves to approach the second base station 22, the first The signal strength of the base station 21 decreases and the signal strength of the second base station 22 gradually increases. The mobile station 10 then sends a pilot offset to the first base station 21 to perform handoff with the second base station 22. Then, the first base station 21 transmits a pilot offset, which is an identifier of the received second base station, to the control station 30, and the control station 30 that receives the pilot offset is stored in its storage device, PLD. Retrieve a neighbor list for the second base station 22. The neighbor list stores pilot offset values of base stations that can be handed off from a specific base station and parameters for the base station. If the pilot offset of the second base station 22 is registered in the neighbor list of the control station 30, a handoff to the second base station 220 is requested.

In this operation, handoff is performed so that the mobile station 10 can continue to communicate without disconnection even after moving from the first base station 21 to the service area of the second base station 22.

However, in the mobile communication system as described above, if the pilot offset for the second base station 22 is not registered in the neighbor list, the handoff is not performed and the call service is stopped. Therefore, the operator should input the information of all base stations that can be handed off to the neighbor list of the control station 30 in consideration of the radio wave environment of the adjacent base station 20 when the system is installed. At this time, since the operator must input the list directly, when the neighbor list is corrupted due to an incorrect input of the list or an error in the storage device of the control station 30, or the neighboring base station provided by the mobile station 10 If the pilot power strength of the antenna is incorrectly measured and not registered in the neighbor list, call service may be interrupted.

Accordingly, the present invention has been proposed to solve the conventional problems as described above, and an object of the present invention is to automatically register information of neighbor base stations in a neighbor list in a mobile communication system without an operator directly inputting a neighbor list. The present invention provides a method for automatically registering a neighbor list in a mobile communication system so as to handle a smooth handoff.

The neighbor list automatic registration method of the mobile communication system according to the present invention for achieving the above object,

When the mobile station transmits a pilot offset for handoff to a second base station (base station in a new service area) to the first base station due to a decrease in the pilot power strength of the first base station (the base station currently being served by the mobile station), The base station transmits the received pilot offset to the control station; Receiving the pilot offset, the control station searches whether a neighbor list for the second base station is registered in the PLD, and if the neighbor list is not registered as a result, transmitting a pilot offset of the second base station to the BSM; Receiving the pilot offset, searching for whether a pilot offset of a second base station exists in a neighbor list of a PLD which is a storage device of the BSM; If the corresponding pilot offset is registered in the search result BSM, the BSM transmits all information of the neighbor list corresponding to the first base station to the control station, and the receiving control station receives the neighbor to the first base station stored in its PLD. Deleting all lists and updating the neighbor list with the neighbor list information received by the BSM; After the control station adds the neighbor list received by the BSM, it comprises the step of requesting a handoff to the second base station.

In addition, as a result of the pilot offset search in the BSM, the pilot offset of the corresponding base station (second base station) is not registered in the neighbor list from the beginning due to the operator's mistake in the neighbor list or the wrong cell plan. In the case, the step of retrieving the PLD containing the pilot offsets of all the base stations of the PLD stored in the BSM and collecting information of the second base station matching the pilot offset requesting the handoff; And adding the information of the second base station to the neighbor list of the BSM and transmitting a signal to the control station to add the neighbor list.

1 is a block diagram of a general mobile communication system;

2 is a boundary area diagram between base stations of a typical mobile communication system;

3 is a flowchart illustrating a handoff method of a general mobile communication system;

4 is a schematic view showing a general PCS system;

5 is a signal flow diagram for carrying out the present invention;

6 is a flowchart illustrating a method for automatically registering a neighbor list in a mobile communication system according to the present invention.

<Explanation of symbols for main parts of the drawings>

10: mobile station 21, 22: first and second base stations

30 control station 40 exchange station

50: Base Station Management (BSM)

Hereinafter, a preferred embodiment of the automatic registration method of the neighbor list in the mobile communication system of the present invention according to the above technical concept will be described in detail with reference to the accompanying drawings.

5 is a signal flow diagram for performing a method of automatically registering a neighbor list in a mobile communication system according to the present invention.

As shown therein, the mobile station 10 approaches the handoff region, and transmits a pilot offset for handoff to the second base station 22 to the first base station 21 among several received pilot power strengths. do. The first base station 21 then transmits this received pilot offset to the control station 30, and the control station 30 searches whether the neighbor list of the second base station 22 is registered.

As a result, if the neighbor list is registered in the PLD of the control station 30, handoff is performed to the second base station 22. If the neighbor list is not registered as a result of the search of the control station 30, the control station 30 transmits a pilot offset of the second base station 22 to check whether the neighbor list is registered in the BSM 50. In addition, the BSM 50 receives the search for whether the pilot offset corresponding to the neighbor list of the PLD which is its storage device is registered.

As a result, if the pilot offset is registered in the BSM 50, the BSM 50 transmits all the information of the neighbor list corresponding to the first base station 21 to the control station. Upon receiving this, the control station deletes all neighbor lists for the first base station 21 stored in the PLD, adds the neighbor list received by the BSM 50, and performs a handoff to the second base station 22. Allow. As a result, the mobile station 10 can continue to communicate without disconnection of the call service even after moving from the first base station 21 to the service area from the second base station 22.

On the other hand, if the base station does not exist in the neighbor list from the beginning due to a search result in the BSM 50, deletion of a neighbor list due to an operator's mistake, or a wrong cell plan, among the PLDs stored in the BSM 50, The PLD containing the pilot offsets of all the base stations to be added to the neighbor list is retrieved, the information of the base station 20 corresponding to the pilot offset for which the handoff is requested is collected, and this information is then added to the neighbor list of the BSM 50. In addition to this, the handoff is performed by transmitting the neighbor list addition command signal to the control station 30 at the same time.

6 is a flowchart illustrating a method for automatically registering a neighbor list in a mobile communication system according to the present invention.

As shown, when the mobile station 10 is located in the service area of the first base station 21 and is provided with the service of the first base station 21, the mobile station 10 moves and belongs to the service area of the second base station 22. In step ST31, the pilot offset for handoff to the second base station 22 is transmitted to the first base station 21, and the first base station 21 transmits the received pilot offset to the control station 30. .

In step ST32, it is searched whether the information of the requested second base station 22 is registered in the neighbor list of the control station 30, and as a result, the information about the second base station 22 in the PLD neighbor list of the control station 30. If is registered, go to step ST38 to perform handoff. If, as a result of the search in step ST32, the information of the second base station 22 corresponding to the neighbor list is not registered, the process moves to step ST33, and in step ST33, the second base station 22 for checking the neighbor list in the BSM 50; Transmits a pilot offset.

In step ST34, the BSM 50 having received the pilot offset of the second base station 22 searches whether the pilot offset of the second base station 22 corresponding to the neighbor list of the PLD is registered. As a result of the search, if the requested base station is registered in the neighbor list, the BSM 50 moves to step ST37 to transmit all the information of the neighbor list corresponding to the first base station 21 to the control station 30, and receives it. One control station 30 deletes all neighbor lists for the first base station 21 stored in the PLD, adds the neighbor list received by the BSM 50, and allows handoff to the second base station. do.

In step ST34, if there is no base station requested in the neighbor list, in step ST35, the pilot offsets of all the base stations to be added to the neighbor list are registered based on the received pilot offset among the PLDs stored in the BSM 50. The PLD is retrieved, and in step ST36, information of the base station matching the pilot offset for which the handoff is requested is collected, and this information is added to the neighbor list of the BSM 50.

In step ST37, all of the neighbor list information corresponding to the first base station 21 is transmitted to the control station 30, and the receiving control station 30 receives the neighbor list for the first base station 21 stored in the PLD. After all are deleted, the neighbor list received by the BSM 50 is newly added, and in step ST38, a handoff execution message is transmitted to the first base station 21. This facilitates handoff and prevents disconnection.

As described above, the method of automatically registering the neighbor list in the mobile communication system according to the present invention is automatically performed even in a situation where call service is to be stopped without handoff due to an operation problem or a system problem. By restoring the system to enable the call service, the service provider has the effect of increasing the call completion rate and enabling the service without disconnection, thereby increasing the reliability of the system.

In addition, it is possible to reduce errors caused by the operator operating the neighbor list in the system and to automatically maintain the optimum neighbor list according to the cell environment, thereby achieving smooth handoff.

Claims (1)

A method for automatically registering neighbor information in a mobile communication system including a control station manager (BSM), a base station, a control station, and a mobile station, When the mobile station receives the service from the first base station and moves to belong to the service area of the second base station, the pilot offset of the second base station is transmitted to the first base station among the received pilot power strengths, and the first base station is transmitted. The base station transmitting the received pilot offset to the control station; The control station searching whether a neighbor list of a second base station is registered; If the corresponding neighbor list is registered in the PLD of the search result control station, the handoff instruction command is transmitted to the second base station. If the corresponding neighbor list is not registered, the pilot offset of the second base station is transmitted to the BSM. Steps; The BSM searching for whether a pilot offset corresponding to a neighbor list of a PLD which is its storage device is registered; If the pilot offset is registered in the BSM as a result of the search in the BSM, transmitting all information of the neighbor list corresponding to the first base station to the control station; Deleting, by the control station, all neighbor lists for the first base station stored in the PLD, adding the neighbor list transmitted by the BSM, and allowing handoff to a second base station; If the base station does not exist in the neighbor list of the BSM as a result of the search in the BSM, the PLD including the pilot offsets of all the base stations to be added to the neighbor list among the PLDs stored in the BSM is searched for, and a handoff is requested. Collecting information of the base station that matches the offset; Adding the collected information to a neighbor list of the BSM and simultaneously transmitting a command to the control station to add the neighbor list; The control station receiving the command comprises the step of transmitting an indication command to the second base station automatic registration method of the neighbor list in a mobile communication system.