CN100463558C - Implementation method of fast hard handover of mobile terminal between cells - Google Patents

Abstract

The invention discloses a method for realizing fast hard handover of a mobile terminal between cells, comprising steps: after the base station is powered on, obtains the basic configuration information of the cell; when the terminal is successfully activated in a cell, the base station activates the wireless resources of the terminal The control context information is recorded as the activated terminal configuration information of the cell; the base station records the radio resource control context information of the activated terminal as the activated terminal configuration information of all candidate handover neighboring cells corresponding to the cell; when the terminal moves from the source cell to For the target cell, the target cell establishes the radio resource control context information according to the recorded radio resource control context information of the activated terminal, and establishes the mapping relationship with the physical channel; the source cell notifies the activated terminal to perform hard handover, and informs the handover the target cell; the activated terminal synchronizes to the target cell. The invention shortens the response speed of the hard handover and reduces the signaling load of the air interface.

Description

Implementation method of fast hard handover of mobile terminal between cells

technical field

The invention relates to a method for handover of a mobile terminal between cells in a wireless communication system, in particular to a method for realizing fast hard handover of a mobile terminal between cells.

Background technique

In a mobile communication system, a user will move between different cells. In order to maintain the service used, such as a call, it is necessary to disconnect the terminal from the current cell through a handover process, and establish a connection between the terminal and the new cell in the new cell.

The existing soft handover technology brings limited gain due to high signaling and system overhead and complex equipment implementation. With the continuous development of mobile communication systems, soft handover is gradually being replaced by other technologies (such as hard handover).

However, if hard handover is used in all cases, it means that the number and frequency of hard handover will be much higher than that of the existing system. Therefore, it is urgent to optimize the hard handover process to improve the response speed of hard handover, reduce the signaling load of the air interface, and ensure that the subjective experience of the user's call or service is still good when hard handover occurs at a relatively high frequency. .

Contents of the invention

The technical problem to be solved by the present invention is to provide a method for implementing fast hard handover of a mobile terminal between cells, optimize the hard handover process, shorten the response speed of hard handover, and reduce the signaling load of the air interface, so as to use suitable and efficient hard handover The switching method makes the processing of the network and the terminal simple and targeted, and achieves the optimal performance of the network.

In order to solve the above problems, the present invention provides a method for implementing fast hard handover of a mobile terminal between cells, comprising the following steps:

After the base station is powered on, obtain the basic configuration information of the cell, including the cell information of each cell under the base station, and all candidate handover neighbor cell information of each cell;

When the terminal is successfully activated in a cell, the base station records the radio resource control context information of the activated terminal as the activated terminal configuration information of the cell, and according to the candidate handover neighbor cell information corresponding to the cell, The resource control context information is recorded as the activated terminal configuration information of all candidate handover neighboring cells corresponding to the cell;

When the terminal moves from the source cell to the target cell, the target cell, as one of the candidate handover neighbor cells of the source cell, establishes the radio resource control context information according to the recorded radio resource control context information of the activated terminal, and establishes the The mapping relationship of physical channels;

The source cell notifies the activated terminal to perform hard handover, and informs the handover target cell;

The activated terminal synchronizes to the target cell.

The present invention may further comprise the steps of:

After the synchronization is successful, delete the radio resource control context information of the activated terminal from the source cell and all candidate handover neighboring cells of the source cell except the target cell;

According to the candidate handover neighboring cell information corresponding to the target cell, the base station records the radio resource control context information of the activated terminal as the active terminal configuration information of all candidate handover neighboring cells corresponding to the target cell.

Alternatively, the following steps may be further included:

After the synchronization is successful, delete the radio resource control context information of the activated terminal from the source cell and all candidate handover neighboring cells of the source cell;

The base station records the radio resource control context information of the activated terminal as the activated terminal configuration information of the target cell;

According to the candidate handover neighboring cell information corresponding to the target cell, the base station records the radio resource control context information of the activated terminal as the active terminal configuration information of all candidate handover neighboring cells corresponding to the target cell.

The present invention optimizes the hard handover processing process by synchronizing the configuration information among the hard handover candidate base stations, so that these base stations can obtain sufficient parameter configuration information before the hard handover occurs, avoiding the resource preparation and establishment process inside the base station side, and thus It has the following obvious technical effects:

In the existing hard handover process, it takes a long time to wait for the target cell to prepare and establish the resources required by the terminal during the hard handover process; however, in this technical solution, the target cell has already prepared and established the terminal before the hard handover process required resources, thereby shortening the response speed of hard handover;

In the existing hard handover process, during the hard handover process, the handover command of the air interface and the signaling interaction of the handover completion are required; and the air interface process in this technical solution is simplified to trigger the handover and the air interface synchronization process, so the air interface is reduced. signaling load;

Through the optimization of the hard handover process, a suitable and efficient hard handover method makes the processing of the network and the terminal simple and targeted, and achieves the optimal network performance.

Description of drawings

Fig. 1 is a flowchart of a method for implementing fast hard handover according to the present invention;

Fig. 2 is a flow chart of implementing fast hard handover based on fast handover base station candidate technology according to an embodiment of the present invention

Detailed ways

As shown in Figure 1, it is a flow chart of the fast hard handover implementation method according to the present invention. First, after the base station is powered on, the basic configuration information of the cell is obtained, including the cell information of each cell under the base station, and each cell All candidate handover neighboring cell information (step 101); Then, when the terminal is successfully activated in a cell, the base station records the radio resource control context information of the activated terminal as the activated terminal configuration information of the cell (step 102); The corresponding candidate handover adjacent cell information of each cell, the base station records the radio resource control context information of the activated terminal as the active terminal configuration information of all candidate handover adjacent cell corresponding to the cell (step 103); When the cell moves to the target cell, the target cell is one of the candidate handover neighboring cells of the source cell, and according to the recorded radio resource control context information of the activated terminal, the radio resource control context information is established, and the mapping relationship with the physical channel is established (step 104); the source cell notifies the activated terminal to perform hard handover, and informs the target cell of the handover (step 105); the activated terminal synchronizes to the target cell (step 106).

Among them, the basic configuration information of the cell includes:

(1) Cell information of each cell under the base station, including cell identification number, frequency point, and scrambling code;

(2) For each cell, a list of all possible hard handover neighboring cells of the cell, and the cell information of these neighboring cells, including cell identification number, frequency point, and scrambling code.

The activation terminal configuration information includes:

(1) For each cell, radio resource control context information of all activated terminals under the cell, including signaling bearer information and service bearer information used by the terminal;

(2) For each cell, the radio resource control context information of the active terminal that may be switched in as a candidate hard handover neighbor cell includes signaling bearer information and service bearer information used by the terminal.

Wherein, the information of all candidate handover neighboring cells of each cell may be determined during network planning in the form of a list of candidate handover neighboring cells, and stored at the base station side.

In the initial network planning, according to the location and coverage relationship of each cell, the candidate handover neighboring cells of each cell can be determined at the cell level, and the information can be stored in the base station side in the form of a list.

Although the information of each cell itself, as well as various cell planning information such as the corresponding relationship with all candidate handover neighbors, can be recorded and stored in various forms and formats, there is currently a related technology called: fast Handover base station candidates (Fast Handover eNodeB Candidates, FHBC). The FHBC can be understood as a list file (Profile) that records the basic configuration information of the cell and the configuration information of the activated terminal, and is placed on the side of the base station. It organizes data with cells as the basic unit. For each cell, there are records:

(1) Configuration information of the cell itself, cell identification number, frequency point, scrambling code;

(2) The adjacent cell list of the cell, including several adjacent cells, and the configuration of the adjacent cells (cell identification number, frequency point, scrambling code);

(3) RRC context information and cell description of all activated terminals in the cell (that is, the identity of the cell as a serving cell, which is different from (4) below);

(4) In the neighboring cell of this cell (and possibly other cells) (at this time, it serves as the identity of the adjacent cell, that is, the identity of the non-serving cell), the wireless resources of the terminals that may enter but have not yet been handed over Control context information.

In addition, FHBC technology also includes FHBC generation, maintenance, management, and processes related to synchronizing terminal RRC context information between base stations, using terminal RRC context information to obtain parameter configuration information, and so on.

Next, taking FHBC as an example, the realization of the present invention will be further introduced in detail.

According to the embodiment of the present invention, fast hard handover can be realized based on FHBC technology. By synchronizing FHBC information between hard handover candidate base stations, these base stations can obtain sufficient parameter configuration information before hard handover occurs, avoiding internal The resource preparation and establishment process greatly shortens the response speed of hard handover and saves the signaling interaction of the air interface.

Embodiments of the present invention may include the following steps:

Step 1: Define FHBC. The FHBC is placed on the side of the base station and consists of basic cell configuration information and activated terminal configuration information.

The second step: FHBC initialization. After the base station is powered on, obtain the basic configuration information of the cell. Know the cell information of each cell under the base station, including the cell identification number, frequency point, and scrambling code, and fill it into the cell information of the basic cell configuration information of FHBC; know all possible candidate hardware for each cell under the base station Handover neighboring cell information, including cell identification number, frequency point, scrambling code, and fill these candidate hard handover neighboring cell information into the cell candidate hard handover neighboring cell list in the basic cell configuration information of FHBC

Step 3: When the terminal is successfully activated in a cell, record the radio resource control context information of the activated terminal in the activated terminal configuration information of the cell in FHBC; at the same time, record the radio resource control context information of the activated terminal synchronously in Each candidate hard handover neighboring cell of the FHBC cell is activated in the terminal configuration information.

Step 4: The activated terminal moves from the coverage of the source cell to the coverage of the target cell.

Step 5: Since the target cell has obtained the RRC context information of the activated terminal through the FHBC candidate hard handover adjacent cell activation terminal configuration information in advance, the target cell directly establishes the RRC context information and establishes the wireless The mapping relationship between resource control context information and physical channels.

Step 6: The source cell notifies the activated terminal to perform hard handover, and informs the handover target cell.

Step 7: The activated terminal synchronizes with the target cell, and the synchronization means successful handover.

Step 8: After the handover is successful, delete the radio resource control context information of the active terminal from the source cell recorded in the FHBC, and delete the radio resource control context information of the active terminal from all candidate handover neighboring cells of the source cell recorded in the FHBC contextual information.

Step 9: After the handover is successful, the target cell becomes the serving cell, record the radio resource control context information of the activated terminal in the serving cell of FHBC, and record the radio resource control context information of the activated terminal in the serving cell of FHBC All candidate handover neighbors of the cell.

For the second step, further, if there is a change in the basic configuration information of the cell that adds a cell, deletes a cell, or modifies the adjacent configuration relationship after the base station is powered on, then the FHBC will be re-initialized.

As shown in FIG. 2 , it is a schematic diagram of an implementation process of fast hard handover based on fast handover base station candidates according to an embodiment of the present invention.

Setting scenario: The overlay network consists of cell 1, cell 2, cell 3, and cell 4. Terminal 1 is activated in cell 2 and moves to cell 3.

Step 110: FHBC initialization, its content is as shown in Table 1:

Table 1

Community information Candidate Handover Cell List Activate the radio resource control context information of the terminal Cell 1 Cell ID 1, frequency 988, scrambling code 58 Cell 2 currently no Cell 2 Cell ID 1, frequency 988, scrambling code 58 District 1 District 3 currently no Cell 3 Cell ID 1, frequency 988, scrambling code 58 District 2 District 4 currently no Cell 4 Cell ID 1, frequency 988, scrambling code 58 Cell 3 currently no

Step 120: Terminal 1 is activated in cell 2, and FHBC is updated. Record the radio resource control context information of terminal 1 in the radio resource control context information of the active terminal in cell 2 of FHBC; in all handover candidate cells in cell 2 of FHBC, that is, the active terminal in cell 1 and cell 3 The radio resource control context information records the radio resource control context information of the terminal 1 . The updated FHBC is shown in Table 2:

Table 2

Community information Candidate Handover Cell List Activate the radio resource control context information of the terminal Cell 1 Cell ID 1, frequency 988, scrambling code 58 Cell 2 Terminal 1: Signaling bears 3.4k; service bears AMR12.2k Cell 2 Cell ID 1, frequency 988, scrambling code 58 District 1 District 3 Terminal 1: Signaling bears 3.4k; service bears AMR12.2k Cell 3 Cell ID 1, frequency 988, scrambling code 58 District 2 District 4 Terminal 1: Signaling bears 3.4k; service bears AMR12.2k Cell 4 Cell ID 1, frequency 988, scrambling code 58 Cell 3 currently no

Step 130: Terminal 1 moves from the coverage area of cell 2 to the coverage area of cell 3;

Step 140: According to the radio resource control context information of terminal 1 in cell 3 recorded in the FHBC, directly establish radio resource control context information for terminal 1 in cell 3, and establish a mapping relationship between radio resource control context information and physical channels ;

Step 150: cell 2 notifies terminal 1 to perform hard handover, and the target cell is cell 3;

Step 160: Terminal 1 synchronizes to cell 3, and the synchronization means that the handover is successful;

Step 170: After the handover is successful, the cell 3 replaces the cell 2 and becomes the serving cell of the terminal 1, and updates the FHBC record accordingly. Delete the radio resource control context information of terminal 1 in cell 1 recorded in FHBC, and record the radio resource control context information of active terminals in cell 2 and cell 4 in the new handover candidate cell of cell 3 of FHBC RRC context information of terminal 1. The updated FHBC is shown in Table 3:

table 3

Community information Candidate Handover Cell List Activate the radio resource control context information of the terminal Cell 1 Cell ID 1, frequency 988, scrambling code 58 Cell 2 currently no Cell 2 Cell ID 1, frequency 988, scrambling code 58 District 1 District 3 Terminal 1: Signaling bears 3.4k; service bears AMR12.2k Cell 3 Cell ID 1, frequency 988, scrambling code 58 District 2 District 4 Terminal 1: Signaling bears 3.4k; service bears AMR12.2k Cell 4 Cell ID 1, frequency 988, scrambling code 58 Cell 3 Terminal 1: Signaling bears 3.4k; service bears AMR12.2k

Claims (9)

1. A method for implementing fast hard handover of a mobile terminal between cells, characterized in that it comprises the following steps: After the base station is powered on, obtain the basic configuration information of the cell, including the cell information of each cell under the base station, and all candidate handover neighbor cell information corresponding to each cell; When the terminal is successfully activated in a cell, the base station records the radio resource control context information of the activated terminal as the activated terminal configuration information of the cell, and according to the candidate handover neighbor cell information corresponding to the cell, The resource control context information is recorded as the activated terminal configuration information of all candidate handover neighboring cells corresponding to the cell; When the terminal moves from the source cell to the target cell, the target cell, as one of the candidate handover neighbor cells of the source cell, establishes the radio resource control context information according to the recorded radio resource control context information of the active terminal, and establishes the The mapping relationship of physical channels; The source cell notifies the activated terminal to perform hard handover, and informs the handover target cell; The activated terminal synchronizes to the target cell. 2. The method according to claim 1, further comprising the steps of: After the synchronization is successful, delete the radio resource control context information of the activated terminal from the source cell and all candidate handover neighboring cells of the source cell except the target cell; According to the candidate handover neighboring cell information corresponding to the target cell, the base station records the radio resource control context information of the activated terminal as the active terminal configuration information of all candidate handover neighboring cells corresponding to the target cell. 3. The method according to claim 1, further comprising the steps of: After the synchronization is successful, delete the radio resource control context information of the activated terminal from the source cell and all candidate handover neighboring cells of the source cell; The base station records the radio resource control context information of the activated terminal as the activated terminal configuration information of the target cell; According to the candidate handover neighboring cell information corresponding to the target cell, the base station records the radio resource control context information of the activated terminal as the active terminal configuration information of all candidate handover neighboring cells corresponding to the target cell. 4. The method according to claim 1, wherein the cell information includes: cell identification number, frequency point, and scrambling code. 5. The method according to claim 1, wherein the information of all candidate handover neighboring cells of each cell includes: cell identification number, frequency point, and scrambling code. 6. The method according to claim 1, wherein the radio resource control context information of the activated terminal includes: signaling bearer information and service bearer information used by the terminal. 7. The method according to claim 1, wherein the basic cell configuration information is determined during network planning and stored at the base station side. 8. The method according to claim 1, wherein the basic cell configuration information is determined during network planning, and is stored at the base station side based on fast handover base station candidates. 9. The method according to claim 8, wherein after the base station is powered on, the step of acquiring basic cell configuration information is performed by initializing fast handover base station candidates defined in advance and stored at the base station side.

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