CN1429033A - Witching method between systems - Google Patents

Abstract

The invention discloses a method for handover between systems, comprising: user equipment monitors the signal quality of the original cell, and reports the measurement result to the network when the monitored signal quality is lower than a predefined threshold, and the network determines the signal quality according to the reported result Dedicated physical control channel gating technology is used for inter-system measurement, and DPCCH gating parameters on the UE and base station side are configured, as well as transmission format set. Perform the synchronization and signal quality measurement of adjacent system cells in the gap between adjacent systems, and report the measurement results to the network. The network judges whether inter-system handover is required based on the measurement results. If necessary, it notifies the UE to complete the inter-system handover at the specified time; adopt the above scheme It can not only make full use of the gate control gap, improve the resource utilization rate of the system, but also shorten the transmission interval of the TPC, and prevent the degradation of the signal quality of the original link in the handover area.

Description

A method for switching between systems

technical field

The invention relates to a handover method between different base stations for user equipment (UE) in a mobile communication system, especially a handover method between systems.

Background technique

In a mobile communication system, when a UE moves from a local base station to a target base station, handover between base stations is usually involved. Since the wireless access methods of the two base stations may be different, inter-system handover is caused. The existing inter-system handover scheme is completed using the compressed mode. The specific method is: when the UE detects that the signal quality of the original cell is lower than a certain predefined threshold, it reports the measurement result to the network. According to the reported result, the network Configure the compressed mode parameters on the UE and the base station side through signaling and start the compressed mode. The UE performs synchronization and signal quality measurement of adjacent system cells through the gap generated by the compressed mode, and reports the measurement results to the network. The network determines whether to Perform inter-system handover. When handover is required, notify the UE to perform the handover through signaling. After receiving the handover command, the UE will cut off the connection with the original cell at a specified time and establish a connection with the adjacent system cell. The key of inter-system handover is to use the gap generated by the compressed mode to synchronize and measure adjacent system cells. Due to the large gap generated by the compressed mode, more power control bit information may be lost, resulting in poor performance of the data transmission link. In the process of switching between systems, the signal quality itself has deteriorated, and accurate power control is required. Control to prevent link quality degradation, so the existing handover method between systems is not conducive to preventing link quality degradation.

Contents of the invention

The purpose of the present invention is to provide an inter-system handover method which is beneficial to prevent link quality degradation.

In order to achieve the above purpose, the intersystem handover method provided by the present invention includes:

(1) The user equipment (UE) monitors the signal quality of the original cell, and reports the measurement result to the network when the monitored signal quality is lower than a predefined threshold;

(2) According to the reported results, the network determines to use the Dedicated Physical Control Channel (DPCCH) gating technology for inter-system measurement, and configures the DPCCH gating parameters on the UE and base station side, and configures the Transport Format Set (TFS);

(3) The UE and the network side perform gating according to the gating parameters, and the UE uses the gap generated by the DPCCH gating technology to perform synchronization and signal quality measurement of adjacent system cells, and report the measurement results to the network;

(4) The network judges whether inter-system handover is required according to the measurement results, and if necessary, notifies the UE to perform the handover;

(5) The UE completes the inter-system handover at a specified time according to the handover notification.

The above step (3) also includes: buffering the data in the packet domain (PS), waiting for the gating gap to end before sending, and discarding the data in the circuit domain (CS).

The above content can also be replaced by the following content: buffer the data in the packet domain (PS), wait for the end of the gating gap before sending, and send data that meets the TFS requirements for the data in the circuit domain (CS).

The above step (3) further includes: reading transmission power control (TPC) information in the DPCCH during the gating gap, and using the information to keep power control continuous.

Since the present invention uses the DPCCH gating gap for inter-system measurement, cell synchronization and measurement can be performed, thereby completing inter-system handover, which not only makes full use of the gating gap, improves the resource utilization rate of the system, but also shortens the TPC time. transmission interval, thus preventing degradation of the signal quality of the original link in the handover area.

Description of drawings

Fig. 1 is the flow chart of the embodiment of the method of the present invention;

Figure 2 is a gating gap diagram;

Fig. 3 is a flow chart of inter-system handover signaling when the present invention is applied.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings.

The DPCCH gating technology is applicable to uplink and downlink data transmission links. When there is no data to be sent, stop sending DPCCH, and when there is data to be sent, resume the sending of DPCCH and DPDCH (dedicated physical control channel and dedicated physical data channel). Since the gating technology adopts the above scheme, compared with the compression mode, the gating gap generated by it in a data frame is discontinuous, making the gating gap smaller. If the gating technology is used to switch between systems, the lost TPC information is less. The essence of the present invention is that the UE performs inter-system cell synchronization and measurement through the gap generated by the DPCCH gating technology, which can maintain the continuity of power control and improve the performance of inter-system switching while providing the physical frame gap.

Fig. 1 is the flow chart of the embodiment of the method of the present invention. Implement the present invention according to Fig. 1, step 1, the user equipment monitors the signal quality of the original cell, and judges the monitored signal quality, and reports the measurement result to the network when the monitored signal quality is lower than the predefined threshold ; Step 2. According to the reported results, the network determines to use the Dedicated Physical Control Channel (DPCCH) gating technology for inter-system measurement, and configures the DPCCH gating parameters on the UE and base station side, and configures the Transport Format Set (TFS); Step 3: The UE and the network side perform gating according to the gating parameters, and the UE uses the gap generated by the DPCCH gating technology to perform synchronization and signal quality measurement of adjacent system cells, and report the measurement results to the network. During the DPCCH gating gap in this step, the DPDCH corresponding to the gating gap is processed separately according to the data type, the data in the PS domain is buffered, and the data is sent after the gap is completed; and for the CS domain data, the data is discarded Or only send part of the data, but the size of the sent data meets the requirements of TFS, because TFS is limited; during the gating gap in this step, also read the TPC information in the DPCCH, and use this information to maintain power control To prevent further deterioration of the signal quality of the original link; step 4, the network judges whether inter-system handover is required according to the measurement results, and if necessary, notifies the UE to perform the handover; step 5, the UE performs the handover in the specified Switch between systems at all times.

Compared with the compressed mode, since the DPCCH gating gap is smaller than the gap generated in the compressed mode, several consecutive gating gaps can be used together in the specific application of the present invention, refer to FIG. 2 . In the figure, S1 to S6 are gating gaps, and the narrow column part is DPCCH. In practice, S1 to S6 can be used for neighbor cell synchronization, and subsequent gaps are used for measurement.

The following is a specific application example of the present invention, refer to FIG. 3 . As shown in the figure, when the UE detects that the signal quality of the original cell is lower than a predefined threshold, it reports the measurement result of the original cell to the serving base station controller (SRNC) of the network through the measurement report signaling (Measurement Report) According to the reported results, the SRNC determines to use the DPCCH gating technology for inter-system measurement, and then sends the radio link reconfiguration request signaling and the radio bearer reconfiguration request signaling (Radio Link Reconfiguration Request) to the original cell base station (Home BS) and UE respectively. and Radio Bearer Recongfiguration Request) to configure the DPCCH gating parameters on the base station side and the UE side respectively, and configure the restricted TFS. After the parameters are configured, the Home BS and UE send the radio link reconfiguration completion signaling and radio bearer reconfiguration The completion signaling (RadioLink Reconfiguration Complete and Radio Bearer RecongfigurationComplete) feeds back the message that the parameter configuration is completed to the SRNC respectively. The UE and the network side start the DPCCH gating technology at the specified time and on the specified radio frame according to the configuration parameters. The UE performs the synchronization and signal quality measurement of the neighboring system cells through the gap generated by the DPCCH gating technology. The data is buffered first, and the data is sent after the gap is completed; for the CS domain data, the upper layer discards the data or only sends part of the data, and the size of the sent CS domain data meets the requirements of the restricted TFS. After the UE completes the measurement of the adjacent system cell, it reports the measurement result of the adjacent system cell to the network, that is, the SRNC through the measurement report signaling (Measurement Report). After the target base station controller (Target BSC) completes the inter-system handover preparation, the SRNC sends the inter-system handover command signaling (INTER-SYSTEM HANDOVER COMMAND) to the UE to notify the UE to perform an inter-system handover. After receiving the handover command, the UE Cut off the connection with the original cell at the moment, and establish a connection with the cell of the different system. The original cell, that is, the Home BS reports the link failure to the SRNC through the Radio Link Failure Indication (Radio Link Failure Indication), and the SRNC sends the Radio Link Delete Request signaling (Radio LinkDelete Request) to the Home BS according to the link failure indication. ) to delete the original cell link. After establishing a link with the target cell, the UE reports the completion of the handover to the target base station controller through the handover completion signaling (HANDOVER COMPLETE).

Claims (6)

1. A method for switching between systems, comprising: (1) The user equipment (UE) monitors the signal quality of the original cell, and reports the measurement result to the network when the monitored signal quality is lower than a predefined threshold; (2) According to the reported results, the network determines to use the Dedicated Physical Control Channel (DPCCH) gating technology for inter-system measurement, and configures the DPCCH gating parameters on the UE and base station side, and configures the Transport Format Set (TFS); (3) The UE and the network side perform gating according to the gating parameters, and the UE uses the gap generated by the DPCCH gating technology to perform synchronization and signal quality measurement of adjacent system cells, and report the measurement results to the network; (4) The network judges whether inter-system handover is required according to the measurement results, and if necessary, notifies the UE to perform the handover; (5) The UE completes the inter-system handover at a specified time according to the handover notification. 2. The intersystem handover method according to claim 1, characterized in that: said step (1) monitoring the signal quality of the original cell is realized by monitoring the GSM carrier received signal strength indicator (GSMCarrier RSSI). 3. The intersystem handover method according to claim 1, characterized in that: said step (3) carries out the synchronization of adjacent system cells and obtains the absolute carrier frequency number of the broadcast control channel through the identification and verification of the base station identification code (BSIC) (BCCH ARFCN) implementation. 4. The intersystem handover method according to claim 1, characterized in that said step (3) further comprises: buffering the data in the packet domain (PS), waiting for the end of the gating gap before sending it, and transferring the data in the PS domain (CS) data discarded. 5. The intersystem handover method according to claim 1, characterized in that said step (3) further comprises: buffering the data in the packet domain (PS), waiting for the end of the gating gap before sending it, for the circuit domain (CS) data, send data that meets the TFS requirements. 6. The inter-system handover method according to claim 1, 2 or 3, characterized in that said step (3) further comprises: reading transmission power control (TPC) information in the DPCCH during the gating gap, And use this information to keep power control continuous.

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