CN100551161C - Method for handover of mobile terminal - Google Patents

Abstract

The present invention relates to the method that a kind of mobile terminal skip zone switches, comprise the portable terminal that needs handover has been to use the high-speed packet shared channel, also be to use the determining step of dedicated channel; Judge whether to exist the step of the alien frequencies adjacent area of not supporting the high-speed packet shared channel and portable terminal is switched to the alien frequencies adjacent area of not supporting the high-speed packet shared channel and the portable terminal that will use dedicated channel switch to this neighbor cell according to the signal quality of neighbor cell step by the sub-district of using described high-speed packet shared channel.The present invention passes through portable terminal allotted channel resource situation in the sub-district, supporting under the different situation of HSDPA function in the base station in the mobile communications network is provided, to the handover that portable terminal carried out, finish the existing defective of switching between HS-DSCH and the DCH thereby overcome, realized that portable terminal obtains the continuity transmission and covers and carry out the high quality communication service of high speed data transfer in the whole network because of the compact model of taking to start inter-frequency measurement.

Description

Method for handover of mobile terminal

technical field

The present invention relates to a method for handover of a mobile terminal, in particular to a method for handover of a mobile terminal in a wideband code division multiple access (WCDMA) mobile communication system supporting downlink high-speed packet service access .

Background technique

The R99 standard protocol of the WCDMA mobile communication system provides users with a maximum rate of 384kbps, and hot spots can provide a rate of 2Mbps. From the characteristics of the dedicated channel-DCH (dedicated channel) and downlink shared channel-DSCH (downlink shared channel) supported by R99 for the transmission of packet data, for users in general areas, the rate bandwidth provided by the R99 standard protocol will be It cannot meet the needs of users in hotspot areas. Therefore, the R5 standard protocol introduces the high-speed downlink data packet channel-HSDPA (High Speed Downlink Packet Access) function, and introduces the high-speed packet shared channel-HS-DSCH (High Speed Downlink Shared Channel). HS-DSCH adopts time division and code division, and adopts hybrid automatic retransmission and adaptive modulation and coding technology, so that the peak rate can reach 10.8Mbps-30Mbps, thereby increasing WCDMA mobile communication by providing support for high-speed packet service access The capacity of the system and the transmission delay are reduced, thereby improving the service quality for users.

In the above-mentioned R5 standard protocol, the mobile terminal of the UE (User Equipment) that enjoys the high-speed packet shared channel-HS-DSCH does not support soft handover during the moving process, that is to say, the change of the HS-DSCH serving cell is adopted Hard handover, but the basis for hard handover is still the signal strength of the pilot channel of the cell, and the mobile terminal needs to report the measurement result of the pilot channel signal. U.S. Patent No. 6,493,328 "Active set management in cellular wireless network that supports high data rate forward link transmissions" provides the method of selecting the HS-DSCH serving cell in the active set when the mobile terminal of the UE moves between cells with the same frequency and supports HSDPA method. According to the HSDPA networking strategy, generally only cells in hotspot areas support HS-DSCH, so there must be mixed networking of cells that support HS-DSCH and cells that do not support HS-DSCH at the same frequency or different frequencies, as shown in the figure 1. Cell B is a cell that does not support HSDPA and has a large area of co-frequency coverage. Its frequency point is f2. The adjacent cell A is a cell that supports HSDPA and its frequency point is f1. At the same time, this cell A also has a co-coverage Cell A1 that does not support HSDPA. A1 has the same frequency as the adjacent cell B that does not support HSDPA, and the frequency point is also f2. Therefore, cell A is a layered coverage cell with different frequencies. B cells supporting HSDPA have adjacent coverage areas.

In the case of the hybrid network shown in FIG. 1 above, when the mobile terminal 3 performs mobile handover, it needs to complete the handover between the HS-DSCH and the DCH channel to realize cell handover. The currently used handover mode is usually a compressed mode for starting inter-frequency measurement. The disadvantage of this compressed mode for starting inter-frequency measurement is that it easily affects the capacity of the mobile communication system. The mobility management method in this case is not mentioned in the relevant patents; the present invention provides a mobility management method for mobile terminals without starting the compressed mode to ensure continuous coverage.

Contents of the invention

The purpose of the present invention is to adopt the compression mode of starting the inter-frequency measurement to complete the HS-DSCH when the above mobile terminal performs mobile handover in the same-frequency or different-frequency cell hybrid networking mode that supports HS-DSCH and does not support HS-DSCH To solve the defects in the handover between DCH and DCH channels, a method for handover of a mobile terminal is provided. The method judges the status of the channel resources allocated to the mobile terminal in the cell and the Radio Network Controller-RNC (Rdio Network The Controller) judges the communication status of adjacent cells on the channel, and completes the handover of the mobile terminal between the HS-DSCH and DCH channels, thereby realizing the handover of the mobile terminal under continuous coverage of the entire network and high-speed information transmission.

To achieve the above object, the present invention provides a method for handover of a mobile terminal, which includes the following steps:

Step 1, judging whether the mobile terminal requiring handover has used a high-speed packet shared channel or a dedicated channel; if a high-speed packet shared channel is used, step 2 is performed; if a dedicated channel is used, step 4 is performed;

Step 2, judging whether there is an inter-frequency adjacent cell that does not support the high-speed packet shared channel, if there is no such inter-frequency adjacent cell, complete the transfer of the mobile terminal from a serving cell that supports the high-speed packet shared channel to another that supports the high-speed packet shared channel Execute step 5 after the handover of the serving cell of the shared channel; if there is the inter-frequency neighbor cell, proceed to step 3;

Step 3. Execute step 5 after handing over the mobile terminal from the cell using the high-speed packet shared channel to a different-frequency adjacent cell that does not support the high-speed packet shared channel;

Step 4, the radio network controller monitors that the adjacent cell has a signal quality that meets the requirements, then handovers the mobile terminal to the adjacent cell;

Step 5, end.

In the above-mentioned steps, step 1 determines which method is used to switch the mobile terminal. For the mobile terminal using the high-speed packet shared channel, step 2-step 3 is used to make the mobile terminal in two adjacent and both support the mobile terminal. Describe the handover between serving cells that support high-speed packet shared channels, or make mobile terminals switch from cells using high-speed packet shared channels to inter-frequency adjacent cells that do not support high-speed packet shared channels; for mobile terminals that use dedicated channels, use After step 4, the mobile terminal is handed over from the dedicated channel serving cell to its adjacent cell. The adjacent cell may be a serving cell supporting the high-speed packet shared channel, or a hard handover of a serving cell that does not support the high-speed packet shared channel.

Specifically, when a mobile terminal using a high-speed packet shared channel is handed over to an inter-frequency neighboring cell that does not support a high-speed packet shared channel, the detailed steps to be taken are:

Step 3-1. Determine whether the cell that uses the high-speed packet shared channel allocated to the mobile terminal has a same-coverage cell with the same frequency as the different-frequency neighbor cell, and if there is no such same-coverage cell, take The inter-frequency measurement of the compressed mode is started after the handover between the serving cells of the mobile terminal is completed; if the same coverage cell exists, step 3-2 is performed;

Step 3-2, the radio network controller detects the transmission power of the accompanying dedicated physical channel, and when the transmission power exceeds a preset threshold, hard handovers the mobile terminal to the same coverage cell, so that the The mobile terminal switches from using the high-speed packet shared channel to using the dedicated channel, and the switching is completed. When a mobile terminal using a dedicated channel performs handover to an adjacent cell, the detailed steps to be taken are:

Step 4-1, judging whether the service of the mobile terminal satisfies the conditions for migrating to use the high-speed packet shared channel, if the conditions are not met, then perform step 4-3; if the conditions are met, then perform step 4 -2;

Step 4-2, hard handover the mobile terminal to the cell with the same coverage and support the high-speed packet shared channel, so that the mobile terminal switches from using the dedicated channel to using the high-speed packet shared channel, and then Finish;

Step 4-3: When the adjacent cell is a cell of the same frequency and not a cell in the active set of the mobile terminal, the network side completes the soft handover of the mobile terminal, and then ends.

As can be seen from the above technical solutions, the present invention provides the mobile terminal with different handover functions in the mobile communication network under the condition that the base station supports different HSDPA functions through the condition of the channel resources allocated to the mobile terminal in the cell. Handover, the present invention can avoid starting the compressed mode to carry out the handover of the mobile terminal when the conditions permit, overcomes the defects existing in the switching between the HS-DSCH and the DCH due to the adoption of the inter-frequency measurement of starting the compressed mode, and realizes The UE's mobile terminal can obtain high-quality communication services with continuous transmission coverage for high-speed data transmission in the entire network.

Hereinafter, the present invention will be further described in detail through specific embodiments and in conjunction with the accompanying drawings.

Description of drawings

Fig. 1 is a schematic diagram of the composition of two adjacent inter-frequency adjacent cells applied in the present invention;

Fig. 2 is the flow chart that the present invention carries out handover to the mobile terminal using the high-speed packet shared channel;

Fig. 3 is a flow chart of the present invention for handover of a mobile terminal using a dedicated channel.

Detailed ways

When the mobile terminal 3 of the UE performs handover in two adjacent inter-frequency adjacent cells as shown in FIG. The mobile terminal 3 judges whether it uses the high-speed packet shared channel-HS-DSCH or the dedicated channel-DCH. When the cell is a cell B that does not support HS-DSCH, the mobile terminal 3 uses the DCH; When the cell is cell A supporting HS-DSCH, the mobile terminal 3 uses HS-DSCH.

For the mobile terminals 3 in different cells, the present invention provides different specific implementation methods of handover processing through the above judgment steps, and the detailed process is shown in Fig. 2 and Fig. 3 .

FIG. 2 shows a specific handover processing flow adopted by the present invention for a mobile terminal using HS-DSCH.

Step 101, judging whether there is an inter-frequency adjacent cell that does not support HS-DSCH, if there is no such inter-frequency adjacent cell, then perform step 101a, that is, complete normal switching between different serving cells that support HS-DSCH and Change the processing, and then execute step 301 to end; if the inter-frequency adjacent cell exists, continue to execute step 102 . The handover in step 101a may adopt the currently common processing steps of changing the HS-DSCH serving cell.

Step 102, judging whether the cell that uses the high-speed packet shared channel allocated to the mobile terminal has the same coverage cell with the same frequency point as the inter-frequency neighbor cell, and if there is no such same coverage cell, execute step 102a , that is, adopt the inter-frequency measurement of the compressed mode to complete the handover between the serving cells of the mobile terminal, and then execute step 301 to end; if there is the same coverage cell, continue to execute step 103. The handover process in step 102a includes the currently common intra-frequency measurement, inter-frequency measurement initiation and decision steps.

Step 103, start the dedicated measurement of transmission code energy (TCP).

Step 104, the radio network controller (RNC) detects the transmission power of the accompanying DPCH channel, and when the transmission power exceeds a preset threshold value, the mobile terminal is hard handed over to the same coverage cell, so that the The mobile terminal switches from using the HS-DSCH to using the DCH; when the transmission power does not exceed the preset threshold value, it means that the conditions for switching are not met yet, and step 301 can end without any processing.

Step 301, end the handover process.

FIG. 3 shows a specific handover processing flow adopted by the present invention for a mobile terminal using DCH.

Step 201, the RNC monitors that the neighboring cells have satisfactory signal quality (the neighboring cells become the cells with the best signal quality).

Step 202, judging whether there is a cell with the same coverage and supporting HS-DSCH in the adjacent cell, if it does not exist, then jump and execute step 300 in Figure 2 (by node A in Figure 2 and Figure 3); if If it exists, go to step 203. The operation performed in step 300 is to perform handover when the adjacent cell is an intra-frequency cell and not a cell in the active set.

Step 203, judging whether the service of the mobile terminal satisfies the conditions for migrating to use HS-DSCH, if the conditions are not met, jump to and execute step 300 in Figure 2; if the conditions are met, execute step 204. In this step, the condition for migrating to use HS-DSCH is that the service of the mobile terminal is a packet domain (PS) service, that is, PS streaming service or PS interactive service or PS background service, and the mobile terminal has the ability to support the service Ability.

Step 204, the mobile terminal is handed over to the sub-district with the same coverage and supports HS-DSCH, so that the mobile terminal is switched from using DCH to using HS-DSCH, and jumps to step 301 in Fig. 2 (through Fig. 2, Fig. 3 The Node B) of the mobile terminal completes the handover of the mobile terminal based on the HS-DSCH.

In essence, the method provided by the present invention provides a management technical solution for handover of mobile terminals based on high-speed packet shared channels on the basis of reducing costs as much as possible and maximizing system capacity. This technical solution is suitable for mobile communication network groups The network adopts the network mode of using HS-DSCH in hotspot areas, and realizes the switching of cells through the switching of HS-DSCH and DCH channels. The compressed mode of inter-frequency measurement can be started as little as possible, and the system will be avoided when the compressed mode is started. impact on capacity; in addition, in the case that the user service meets the HS-DSCH channel access conditions, this technical solution can access the user service to the HS-DSCH channel in real time, making full use of the high-speed characteristics of the HS-DSCH channel, and improving user quality of service and system capacity.

Claims (6)

1. A method for handover of a mobile terminal, characterized in that the method comprises the following steps: Step 1, judging whether the mobile terminal requiring handover has used a high-speed packet shared channel or a dedicated channel; if a high-speed packet shared channel is used, step 2 is performed; if a dedicated channel is used, step 4 is performed; Step 2, judging whether there is an inter-frequency adjacent cell that does not support the high-speed packet shared channel, if there is no such inter-frequency adjacent cell, complete the transfer of the mobile terminal from a serving cell that supports the high-speed packet shared channel to another that supports the high-speed packet shared channel After the handover of the serving cell of the shared channel, perform step 5; if there is the inter-frequency adjacent cell, then continue to perform step 3; Step 3. Judging whether the cell that uses the high-speed packet shared channel allocated to the mobile terminal has the same coverage cell with the same frequency point as the inter-frequency adjacent cell, and if so, the radio network controller detects the accompanying The transmission power of the dedicated physical channel, when the transmission power exceeds the preset threshold value, the mobile terminal is hard handed over to the same coverage cell, so that the mobile terminal is switched from using the high-speed packet shared channel to Use the dedicated channel, then perform step 5; if it does not exist, then take the inter-frequency measurement that starts the compressed mode to complete the handover between the serving cells of the mobile terminal; Step 4. After the radio network controller monitors that the adjacent cells have satisfactory signal quality, determine whether there is a cell with the same coverage in the adjacent cells that supports the high-speed packet shared channel. If there is a cell with the same coverage and supports all For the cell of the above-mentioned high-speed packet shared channel, the following steps are performed: Step 4-1, judging whether the service of the mobile terminal satisfies the conditions for migrating to use the high-speed packet shared channel, if the conditions are met, perform step 4-2; if the conditions are not met, perform step 4 -3; Step 4-2, hard handover the mobile terminal to the cell with the same coverage and support the high-speed packet shared channel, so that the mobile terminal switches from using the dedicated channel to using the high-speed packet shared channel, and then Execute step 5; Step 4-3. When the adjacent cell is a co-frequency adjacent cell and is not a cell in the active set of the mobile terminal, the network side completes the soft handover of the mobile terminal and then performs step 5; If there is no cell with the same coverage and supporting the high-speed packet shared channel, when the adjacent cell is an adjacent cell with the same frequency and is not a cell in the active set of the mobile terminal, the network side completes the mobile terminal Handoff soft handover; Step 5, end. 2. The method for handover of a mobile terminal according to claim 1, characterized in that in step 1, the step of determining whether the mobile terminal requiring handover uses a high-speed packet shared channel or a dedicated channel is Executed by the radio network controller where the mobile terminal is located, when the cell is a cell that does not support high-speed packet shared channels, the mobile terminal uses a dedicated channel; when the cell is a cell that supports high-speed packet shared channels, the Mobile terminals use high-speed packet shared channels or use dedicated channels. 3. The method for handover of a mobile terminal according to claim 1, characterized in that said inter-frequency measurement that starts the compressed mode to complete the handover process between the serving cells of the mobile terminal includes intra-frequency measurement, inter-frequency measurement, etc. Measurement initiation and decision steps. 4. The method for handover of a mobile terminal according to claim 1, characterized in that before said step 4, there is also a dedicated measurement step for starting transmission code energy. 5. The method for handover of a mobile terminal according to claim 1, characterized in that in step 4-1, the condition for migrating to use the high-speed packet shared channel is that the service of the mobile terminal is in the packet domain Streaming service or packet domain interactive service or packet domain background service, and the mobile terminal has the ability to support the service. 6. The method for handover of a mobile terminal according to any one of claims 1-5, characterized in that in step 2, said handover includes the processing step of changing the serving cell of the high-speed packet shared channel.

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