CN102083161A - Method, system for updating cell in TD-SCDMA (Time Division-Synchronization Code Division Multiple Access) network and user equipment - Google Patents

Abstract

The invention discloses a cell update method, system and user equipment in a TD-SCDMA network, which are used to reduce the call drop rate of UE in the TD-SCDMA network. The cell update method includes: when the user equipment UE confirms that the preset cell update trigger condition is met, select the target cell according to the latest measurement results of same-frequency measurement and inter-frequency measurement, and send a cell update message, which carries the target cell Identification information: After receiving the cell update confirmation message returned by the RNC, the UE accesses the target cell according to the new radio resource allocated for the UE in the target cell indicated therein.

Description

Cell update method, system and user equipment in TD-SCDMA network

technical field

The invention relates to the field of mobile communication, in particular to a cell update method, system and user equipment in a TD-SCDMA (Time Division Synchronous Code Division Multiple Access) network.

Background technique

The basic network structure of the TD-SCDMA (Time Division-Synchronous Code Division Multiple Access) system consists of UE (User Equipment, user equipment), UTRAN (UMTS Terrestrial Radio Access network, UMTS terrestrial radio access network; UMTS: Universal Mobile Telecommunications System (Universal Mobile Telecommunications System) and CN (Core Network, Core Network) are composed of three parts. UTRAN includes NodeB (base station) and RNC (Radio Network Controller, radio network controller) two nodes, RNC is mainly responsible for the management of UTRAN, NodeB is mainly responsible for the transmission and reception of wireless signals. The radio interface of the TD-SCDMA system is divided into three protocol layers: physical layer (L1), data link layer (L2) and network layer (L3). The physical layer is composed of downlink physical channels and uplink physical channels; the data link layer accepts the services of the physical layer and provides services to the network layer, which is divided into MAC (Media Access Control, medium access control) sublayer, RLC (Radio Link Control , wireless link control) sublayer, PDCP (Packet Data Convergence Protocol, packet data convergence protocol) sublayer and BMC (Broadcast/Multicast Control, broadcast/multicast control) sublayer. Among them, the RLC sublayer provides logical link control of the wireless interface, and the services provided by the RLC sublayer to the network layer include:

1. Three modes of data transmission, namely TM (transparent transmission mode), UM (unacknowledged mode) and AM (acknowledged mode);

2. Guarantee the QoS (Quality of Service) of the business through the retransmission protocol;

3. Unrecoverable error notification.

The network layer and RLC sublayer are divided into control plane and user plane. The lowest layer of the network layer control plane is the RRC (Radio Resource Management) sublayer, which is responsible for processing the signaling between the UE and UTRAN on the network layer control plane. The RRC sublayer is divided into idle mode (Idle mode) and Idle mode according to whether there is an RRC connection. Connected mode, which is divided into four states according to the wireless resource allocation in the connected mode: CELL-DCH (cell-dedicated transmission channel) state, CELL-FACH state, CELL-PCH state and URA-PCH state. According to the change of radio resource allocation, the transition between the RRC sublayer states is triggered; the transition between the idle mode and the connected mode is triggered by the establishment and release of the RRC connection.

Compared with the GSM (Global System for Mobile Communications, Global System for Mobile Communications) network, the TD-SCDMA network has a higher UE call drop rate. The main reasons for the UE call drop can be attributed to RLC sublayer problems and physical layer (L1) failures. The step problem can be divided into two situations: downlink and uplink:

For the out-of-sync problem of the physical layer (L1) in the downlink, in the CELL-DCH state, if the out-of-sync indication (out of sync) of the set number of continuous physical layer reports (the specific value is set by setting the parameter N313) is received, the UE The timer will be started (the specific timing value is set by parameter T313). After the timer expires, the UE confirms that the radio link fails and triggers a cell update (Cell Update); for the RLC sublayer problem in the downlink, in the confirmation mode, The loss of downlink data packets (blocks) at the RLC sublayer will lead to retransmission. After the retransmission of downlink data packets reaches the set number of times, the NodeB requires the RNC to reconfigure (Reset) the RLC sublayer. If the reconfiguration reaches the set number of times, the RLC sublayer does not recover. , then the RNC initiates the Iu interface radio resource release (Iu Release), causing actual call drop.

For the out-of-synchronization problem of the physical layer (L1) in the uplink, in the CELL-DCH state, if the physical layer continuously reports a set number of out-of-synchronization indications, the NodeB will start the timer, and notify the RNC after the timer expires Radio link failure (RL fail), RNC initiates Iu Release (Iu interface radio resource release), causes the actual call to drop; For the RLC sublayer problem in the uplink, in confirmation mode, the RLC sublayer loses the uplink data packet ( block) will lead to retransmission. After the retransmission of uplink data packets reaches the set number of times, the UE requests the NodeB to reconfigure (Reset) the RLC sublayer. If no response is obtained or the reconfiguration reaches the set number of RLC sublayers. Idle mode, causing actual call drop.

Contents of the invention

In view of this, the present invention provides a cell update method, system and user equipment in a TD-SCDMA network, so as to reduce the call drop rate of UE in the TD-SCDMA network.

The present invention provides a cell update method in a TD-SCDMA network, comprising:

When the user equipment UE confirms that the preset cell update trigger condition is met, select the target cell according to the measurement results of the latest intra-frequency measurement and inter-frequency measurement, and send a cell update message, which carries the identification information of the target cell;

After receiving the cell update confirmation message returned by the radio network controller RNC, the UE accesses the target cell according to the new radio resource allocated for the UE in the target cell indicated therein.

The present invention provides a cell update system in a TD-SCDMA network, comprising:

The user equipment UE is configured to select a target cell according to the measurement results of the latest intra-frequency measurement and inter-frequency measurement when confirming that the preset cell update trigger condition is met, and send a cell update message, which carries the identification information of the target cell; and After receiving the cell update confirmation message, access the target cell according to the new radio resource indicated therein;

The radio network controller RNC is configured to, when receiving the cell update message sent by the UE, allocate new radio resources for the UE in the target cell indicated by the identification information, and return a cell update confirmation message to the UE.

The present invention provides a user equipment, including:

A control unit, configured to select a target cell according to the latest measurement results of same-frequency measurement and inter-frequency measurement when confirming that the preset cell update trigger condition is met;

a sending unit, configured to send a cell update message, which carries identification information of the target cell;

The update unit is configured to, after receiving the cell update confirmation message, access the target cell according to the new radio resource allocated for the user equipment UE in the target cell indicated therein.

In the cell update method, system and user equipment in the TD-SCDMA network provided by the present invention, the UE triggers the cell update when the preset cell update trigger condition is met, but does not measure adjacent cells, but uses the latest same-frequency measurement The target cell is selected from the measurement results of the inter-frequency measurement, which ensures the timely triggering of the cell update, and at the same time speeds up the cell update process, and restores the service through the triggered cell update, thereby reducing the call drop rate of the UE in the TD-SCDMA network.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Description of drawings

FIG. 1 is a flow chart of cell update in the prior art;

Fig. 2 is a flow chart of a cell update method in a TD-SCDMA network provided by an embodiment of the present invention;

FIG. 3 is a possible structure of a user equipment provided by an embodiment of the present invention;

Fig. 4 is a possible structure of the control unit provided by the embodiment of the present invention.

Detailed ways

The inventors have found that for the UE call drop caused by the RLC sublayer problem and the physical layer (L1) out-of-sync problem in the uplink and downlink, it is mainly because the UE fails to initiate paging in a suitable cell and fails to switch It is not because there are no suitable communities. Based on this, the inventor proposes to reasonably utilize the cell update (Cell Update) process to avoid the call drop of the UE as much as possible, so as to reduce the call drop rate of the UE in the TD-SCDMA network. Cell update is the process of selecting a cell, initiating random access, reestablishing wireless links, and restoring services. From the perspective of users, the interrupted call is restored in time. Through actual tests, it can be concluded that cell update can successfully restore services.

In the prior art, the basic process of cell update is shown in Figure 1, including:

S101. The UE sends a cell update message CELL UPDATA to the UTRAN.

The cell update message includes the cause value of the cell update, U-RNTI (UTRAN Radio Network Temporary Identity), identification information of the target cell selected by the UE through measurement of neighboring cells, and the like. Among them, U-RNTI is used to be allocated to the UE that will establish RRC connection, to distinguish different UEs in the same UTRAN; The identification information includes primary frequency information and CPI (Cell Parameter ID, cell parameter identifier), and CPI is essentially a cell The scrambling code (0-127) and the main frequency information jointly determine a cell.

S102. When the RNC in the UTRAN receives the cell update message sent by the UE, it allocates new radio resources for the UE in the target cell indicated by the identification information, and returns a cell update confirmation message CELL UPDATE CONFIRM to the UE, which carries the physical channel information " Physical channel information elements", indicating the new radio resources allocated for the UE in the target cell.

S103. After receiving the cell update confirmation message, the UE accesses the target cell according to the new radio resource, and sends a physical channel reconfiguration success message PHYSICAL CHANNELRECONFIGURATION COMPLETE to the UTRAN, indicating that the cell update is completed.

There are many reasons for triggering cell update, such as re-entering the service area, RLC unrecoverable error, periodic cell update, cell reselection, radio link failure, etc., which are introduced below:

Cause value 1, re-entering service area

When the UE is in the CELL-FACH or CELL-PCH state, before the timer T307 or T317 expires, if the UE has exceeded the service area and re-enters the service area, the UE will execute the cell whose reason is "re-entering service area". Update procedure to inform UTRAN.

Cause value 2, RLC unrecoverable error (RLC unrecoverable error)

In the confirmation mode, if the UE finds an unrecoverable error in the RLC, the UE will execute the cell update process with the reason value "RLC unrecoverable error" to notify the UTRAN.

Reason value 3, periodic cell update (periodical cell update)

When the UE finds a suitable cell to camp on and is in the CELL-FACH or CELL-PCH state, and the timer T305 cannot be set to "infinity", after the timer T305 expires, the UE will perform a cell update with the reason value "periodical cell update" process to achieve a regulatory mechanism.

Reason value 4, cell reselection (cell reselection)

When the UE is in the CELL-PCH or CELL-FACH state and performs cell reselection, or when the UE is in the CELL-FACH state and the variable C_RNTI (CELL Radio Network Temporary Identity) is empty, the UE will execute the cell with the reason value "cell reselection" The update process is to update the parameters of the current cell where the UE is camped in UTRAN.

Cause value 5, radio link failure

The radio link failure generally includes two situations, one is that the UE has a radio link failure in the CELL-DCH state, and the other is the "UE Capability Information" message transmission failure. When one of the above two situations occurs, the UE will perform the cell update process with the cause value being "Radio link failure".

Reason value 6, uplink data transmission (up link data transmission)

When the UE is in the CELL-PCH or URA-PCH state, if the UE needs to send RLC data PDU (packet data unit) or control PDU on the uplink, and use RB1 or RB with a sequence number greater than 1 to bear, the UE will execute the cause value It is the cell update process of "up link data transmission".

Reason value 7, response paging (utran-paging Response)

When the UE is in the URA-PCH or CELL_PCH state and receives the "PAGING TYPE1" message, if the message meets certain conditions, the UE will execute the cell update process with the cause value being "utran-paging Response".

In the embodiment of the present invention, for the RLC sublayer problem, the cause value carried in the cell update message is "RLCunrecoverable error"; for the physical layer (L1) out-of-sync problem, the cause value carried in the cell update message is "Radio link failure".

Embodiments of the present invention provide a cell update method, system and user equipment in a TD-SCDMA network to reduce the call drop rate of UEs in the TD-SCDMA network. The preferred embodiments of the present invention will be described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described here are only used to illustrate and explain the present invention, and are not intended to limit the present invention, and in the absence of conflict, the present invention The embodiments and the features in the embodiments can be combined with each other.

Embodiment one

This embodiment addresses the problem of out-of-synchronization of the physical layer (L1) in the downlink.

According to the existing technology, in the CELL-DCH state, if it receives N313 out-of-sync indications (out of sync) continuously reported by the physical layer, the UE will start the timer T313. After the timer T313 expires, the UE will confirm that the radio link has failed. Trigger cell update (Cell Update), the UE obtains the RSCP (Receive Signal Code Power, received signal code power) of each adjacent cell through the measurement of the adjacent cell, selects the target cell according to the RSCP of each adjacent cell, and then the UE reports to the UTRAN Send a cell update message, and the RNC in UTRAN returns a cell update confirmation message to UE, indicating the new radio resource allocated for UE in the target cell; UE accesses the target cell according to the new radio resource, and sends physical channel reconfiguration to UTRAN Success message, indicating that the cell update is complete.

The inventors of the present invention have found that the selection of the target cell by the UE needs to be based on the measurement results of neighboring cells, so that the process of selecting the target cell takes a long time, which leads to a long time-consuming cell update process, which leads to a high call drop rate of the UE. one of the factors. In fact, the UE performs intra-frequency measurement (1g) and inter-frequency measurement (2a) in real time, wherein the measurement results of the intra-frequency measurement include the main frequency information, CPI and RSCP of each adjacent co-frequency cell; the inter-frequency measurement measurement The result includes main frequency information, CPI and RSCP of each adjacent inter-frequency cell. The cell update process can directly use the measurement results of the intra-frequency measurement and inter-frequency measurement.

Based on this, an embodiment of the present invention proposes a cell update method in a TD-SCDMA network. After the UE confirms that the radio link fails and triggers the cell update, it does not need to perform adjacent cell measurements, but directly uses the latest same-frequency measurement and For the measurement results of the inter-frequency measurement, just select the target cell. As shown in Figure 2, it includes the following steps:

S201. In the CELL-DCH state, the timer started by the UE after receiving a set number of out-of-synchronization indications continuously reported by the physical layer times out, selects the target cell according to the measurement results of the latest intra-frequency measurement and inter-frequency measurement, and sends the cell The update message CELL UPDATE carries the identification information of the target cell.

In the specific implementation, the cell with the strongest RSCP among the adjacent inter-frequency cells is preferentially selected as the target cell. The precondition is that the strongest RSCP among the RSCPs of each adjacent inter-frequency cell meets the preset signal strength condition. The strongest RSCP among the RSCPs of the inter-frequency cells does not meet the preset signal strength condition, and the cell with the strongest RSCP among the adjacent inter-frequency cells and the adjacent intra-frequency cells is selected as the target cell.

The preset signal strength condition may be that the strongest RSCP among the RSCPs of each adjacent inter-frequency cell is greater than or equal to the configured RSCP threshold, or that the strongest RSCP among the RSCPs of each adjacent inter-frequency cell is greater than the current service RSCP of the cell.

S202. When the RNC receives the cell update message CELL UPDATE sent by the UE, it allocates new radio resources for the UE in the target cell indicated by the identification information, and returns a cell update confirmation message CELL UPDATE CONFIRM to the UE.

In the specific implementation, when the RNC allocates new radio resources for the UE in the target cell according to the received cell update message, if the unoccupied radio resources in the target cell cannot meet the radio resources required by the UE, the radio link with the problem will be released. The radio resource occupied by the road. This part of radio resources is in the state of "waiting for recovery" due to a problem with the radio link. In order to preferentially allocate radio resources for the cell update message, the radio resources in the state of "waiting for recovery" are released in advance.

S203. After receiving the cell update confirmation message CELL UPDATE CONFIRM, the UE accesses the target cell according to the new radio resources indicated therein;

At this time, the cell update on the terminal side is completed, which is consistent with the prior art. Subsequently, the UE may send a physical channel reconfiguration success message PHYSICAL CHANNEL RECONFIGURATION COMPLETE to the UTRAN, indicating that the cell update is completed.

In the specific implementation, the relevant parameters are suggested to be set as follows: N302=3, T302=3, N313=85, N315=1, T313=1s, T314=17s, T315=17s. With the above settings, the service recovery time is at least 5 seconds and at most 14 seconds. The following is a brief description of the meaning of each parameter:

N302: The maximum number of retransmissions of the cell update message.

T302: The UE starts the timer T302 after sending the cell update message, and stops the timer T302 after receiving the cell update confirmation message; once the timer T302 times out, if the number of retransmissions is less than or equal to N302, resend the cell update message, otherwise enter idle model.

N313: The number of out-of-sync indications received continuously from the physical layer.

N315: The number of sync indications received consecutively from the physical layer.

T313: The waiting time after out of sync in the CELL-DCH state. In the CELL-DCH state, if the physical layer continuously reports N313 out of sync indications (out of sync), it means that the established dedicated physical channel may be out of sync. The UE starts the timer T313. If it receives N315 consecutive synchronization indications (in sync) from the physical layer before T313 times out, it considers that the dedicated physical channel is restored and restarts the timer T313. If T313 times out, it considers the radio link to fail, and the UE clears Dedicated physical channel configuration, and trigger cell update, the cause value is radio link failure.

T314: Start the timer T314 when the radio link fails and only the radio access bearer associated with the timer T314 exists (or only RRC is connected), and stop the timer T314 after the cell update is completed. When the radio link failure of the UE in the CELL-DCH state starts the timer T314 and sends a cell update message, before the timer T314 corresponding to the service expires, if the radio link reconfigured by the cell update confirmation message is unsuccessful, it can still Perform wireless link reconfiguration again, T314 is greater than T302 times N302. After the timer T314 expires, the RB (radio bearer) of the corresponding service is deleted.

T315: In the CELL-DCH state, if a radio link failure occurs, the UE will trigger a cell update. Before sending the cell update message, if there is a RAB (Radio Access Bearer) timer T315, and T315 is 0, Then the radio resources allocated for the RAB are released, and the UE enters idle mode; if T315>0, the radio resources allocated for the RAB will not be released temporarily, and the mode of the UE will not change, and the timer T315 will be restarted at the same time. The update process is completed, and T315 will stop. If the timer T315 expires while T302 is still running, wait for the cell update confirmation message. If T302 stops and the cell update process is not completed, release the radio resources of the RAB using the timer T315. If all After the radio resources of the RAB are released, the UE enters the idle mode.

Embodiment two

This embodiment is proposed aiming at the RLC sublayer problem in the uplink.

According to the existing technology, in the confirmation mode, the loss of the uplink data packet (block) at the RLC sublayer will cause retransmission. After the retransmission of the uplink data packet reaches the set number of times, the UE requires the NodeB to reconfigure (Reset) the RLC sublayer. If the RLC sublayer does not recover after getting a response or reconfiguration reaches the set number of times, the UE directly enters the idle mode, resulting in actual call drop. The retransmission of the uplink data packet (Block) in the RLC sublayer and the time consumed for reconfiguring the RLC sublayer can be obtained from RRC SETUP, RB RECONFIGSETUP and other messages and calculated. In specific implementation, the time scale obtained through calculation is 1-10s.

The embodiment of the present invention proposes that in the confirmation mode, if the UE requests the NodeB to reconfigure the RLC sublayer due to the retransmission of the uplink data packet in the RLC sublayer for the set number of times, but does not get a response, or the reconfiguration of the RLC sublayer reaches the set number of times If not restored, cell update is triggered.

In the specific implementation, "because the retransmission of uplink data packets in the RLC sublayer reaches the set number of times, the UE does not get a response after requesting the NodeB to reconfigure the RLC sublayer, or the RLC sublayer has not recovered after the set number of reconfigurations" This cell update trigger condition is pre-configured to the UE, and the "in the CELL-DCH state, the timer expires after the UE receives a set number of out-of-synchronization indications continuously reported by the physical layer" involved in the first embodiment can be regarded as another A cell update trigger condition. If one of the above two cell update trigger conditions is met, the cell update can be triggered.

For the cell update process after the UE triggers the cell update in this embodiment, reference may be made to the specific implementation process provided in Embodiment 1, which will not be repeated here.

Embodiment Three

This embodiment is proposed aiming at the problem of out-of-synchronization of the physical layer (L1) in the uplink and the problem of the RLC sublayer in the downlink.

According to the prior art, in the CELL-DCH state, if the out-of-synchronization indication of the set number of continuous physical layer reports is received, the NodeB will start the timer, and after the timer expires, the RNC will be notified that the radio link fails (RL fail), and the RNC Initiate Iu Release (radio resource release of Iu interface), resulting in actual call drop; in the confirmed mode, the RLC sublayer loses downlink data packet (block) will cause retransmission, after the retransmission of downlink data packet reaches the set number of times, NodeB requires RNC Reconfigure (Reset) the RLC sublayer, if the reconfiguration reaches the set number of times and the RLC sublayer does not recover, then the RNC initiates the Iu interface radio resource release (IuRelease), causing the fact that the call is dropped.

This embodiment proposes that the NodeB stops downlink transmission before the RNC initiates Iu interface radio resource release (Iu release), forcing the UE to trigger cell update. For the out-of-synchronization problem of the physical layer in the uplink, if the physical layer continuously reports a set number of out-of-synchronization indications (for example, if the set number is 85, the out-of-synchronization duration reaches 1s), the NodeB stops downlink transmission, so that the downlink The physical layer in the link is out of sync. According to the existing technology, in the CELL-DCH state, if the UE receives a set number of out-of-sync indications from the physical layer continuously, the UE will start the timer T313. After the timer T313 expires, the UE Confirm that the radio link fails, and trigger cell update. For the specific implementation process, please refer to Embodiment 1, which will not be repeated here. By forcing the UE to trigger cell update to restore services, the UE’s call drop is avoided; similarly, for the RLC in the downlink Sublayer problem, in the confirmation mode, NodeB requires the RNC to reconfigure (Reset) the RLC sublayer after the retransmission of the downlink data packet reaches the set number of times (for example, 25 times). If the reconfiguration reaches the set number of times (for example, 2 times) RLC If the sublayer is not restored, the NodeB stops downlink transmission, which makes the physical layer in the downlink out of synchronization, and also achieves the purpose of forcing the UE to trigger a cell update to resume services.

It should be noted that after the NodeB stops the downlink transmission, if it receives a set number of synchronization indications from the physical layer continuously, indicating that the uplink is restored, the NodeB immediately resumes the downlink transmission.

Based on the same technical idea, the embodiment of the present invention provides a cell update system in a TD-SCDMA network, including:

The user equipment UE is configured to select a target cell according to the measurement results of the latest intra-frequency measurement and inter-frequency measurement when confirming that the preset cell update trigger condition is met, and send a cell update message, which carries the identification information of the target cell; and After receiving the cell update confirmation message, access the target cell according to the new radio resource indicated therein;

The radio network controller RNC is configured to, when receiving the cell update message sent by the UE, allocate new radio resources for the UE in the target cell indicated by the identification information, and return a cell update confirmation message to the UE.

In the specific implementation, the RNC is also used to allocate new radio resources for the UE in the target cell. If the unoccupied radio resources in the target cell cannot meet the radio resources required by the UE, release the radio resources occupied by the problematic radio link. resource.

In specific implementation, the system also includes:

The base station NodeB is used to stop downlink transmission after receiving a set number of out-of-synchronization indications continuously reported by the physical layer in the CELL-DCH state;

Or, in the confirmation mode, when the retransmission of the downlink data packet in the RLC sublayer reaches the set number of times, the RNC is required to reconfigure the RLC sublayer, and if the reconfiguration reaches the set number of times, the RLC sublayer is not recovered, and the downlink transmission is stopped.

Among them, a possible structure of the user equipment UE, as shown in Figure 3, includes:

The control unit 301 is configured to select a target cell according to the measurement results of the latest intra-frequency measurement and inter-frequency measurement when confirming that the preset cell update trigger condition is satisfied;

A sending unit 302, configured to send a cell update message, which carries identification information of the target cell;

The update unit 303 is configured to, after receiving the cell update confirmation message, access the target cell according to the new radio resource allocated for the UE in the target cell indicated therein.

In specific implementation, as shown in Figure 4, the control unit includes a storage subunit 401, a judgment subunit 402 and a selection subunit 403, wherein:

The storage subunit 401 is used to store the measurement results of the latest same-frequency measurement and inter-frequency measurement, the measurement results of the same-frequency measurement include the received signal code power RSCP of each adjacent same-frequency cell, and the measurement results of the inter-frequency measurement The result includes the RSCP of each adjacent inter-frequency cell;

The judgment subunit 402 is configured to determine whether the strongest RSCP among the RSCPs of adjacent inter-frequency cells satisfies the preset signal strength condition when confirming that the preset cell update trigger condition is met, and output the judgment result;

The selection subunit 403 is used to select the cell with the strongest RSCP in each adjacent inter-frequency cell as the target cell when the judgment result output by the judging subunit is yes, and when the judgment result output by the judging subunit is No, select each The cell with the strongest RSCP among adjacent inter-frequency cells and adjacent same-frequency cells is used as the target cell.

Among them, one possible situation to trigger cell update is:

The judging subunit 402 is specifically used to confirm that the preset cell update trigger condition is satisfied if the timer started after receiving a set number of out-of-synchronization indications continuously reported by the physical layer expires in the CELL-DCH state.

Another possible situation to trigger a cell update is:

The judging subunit 402 is specifically used in the confirmation mode, if the retransmission of the uplink data packet in the RLC sublayer reaches the set number of times and the NodeB does not get a response after reconfiguring the RLC sublayer, or the reconfiguration of the RLC sublayer reaches the set number of times. If the layer is not restored, it is confirmed that the preset cell update trigger condition is met.

The technical solution provided by the embodiment of the present invention is to modify the terminal side, and the UE meets the preset cell update trigger condition (specifically for the problem of physical layer out-of-synchronization in the downlink and the RLC sublayer problem in the uplink) The cell update is triggered from time to time, but the adjacent cells are not measured, but the target cell is selected using the latest same-frequency measurement and inter-frequency measurement results, which ensures the timely triggering of the cell update and speeds up the cell update process. Update and restore services, thereby reducing the call drop rate of UEs in TD-SCDMA networks;

The technical solution provided by the embodiment of the present invention upgrades the network side. When the physical layer out-of-sync problem occurs in the uplink and the RLC sublayer problem occurs in the downlink, before the RNC initiates IuRelease to cause the fact that the call is dropped, NodeB stops downlink transmission, forcing UE to trigger cell update to resume business, further reducing the UE's call drop rate; further, when wireless resources are in short supply, RNC releases the wireless resources occupied by the problematic wireless link in advance to ensure that new wireless links are allocated to UE. Resources, so that the UE can complete the cell update in time, thereby reducing the call drop rate of the UE;

The technical solution provided by the embodiment of the present invention is highly compatible, regardless of whether the UE is transformed according to the solution provided by the present invention, it can be compatible with the existing network; regardless of whether the network side is upgraded according to the solution provided by the present invention, it can be compatible with the existing UE .

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and equivalent technologies thereof, the present invention also intends to include these modifications and variations.

Claims (15)

1. the cell update method in the TD-SCDMA network is characterized in that, comprising:

When user equipment (UE) is confirmed to satisfy default cell update trigger condition,, and send cell update message, wherein carry the identification information of Target cell according to the measurement result select target sub-district of nearest common frequency measurement and different-frequency measure;

UE is after receiving the cell update acknowledge message that radio network controller (RNC) returns, according to the new Radio Resource access Target cell that distributes for UE in Target cell of indication wherein.

2. the method for claim 1 is characterized in that, the measurement result of described common frequency measurement comprises the received signal code power RSCP of each adjacent co-frequency cell, and the measurement result of described different-frequency measure comprises the RSCP of each adjacent alien-frequency district; And

The measurement result select target sub-district of common frequency measurement that described basis is nearest and different-frequency measure specifically comprises:

Judge whether RSCP the strongest among the RSCP of each adjacent alien-frequency district satisfies default signal strength conditions;

If, select RSCP is the strongest in each adjacent alien-frequency district sub-district as Target cell, if not, select RSCP is the strongest in the adjacent co-frequency cell with each of each adjacent alien-frequency district sub-district as Target cell.

3. method as claimed in claim 2 is characterized in that, described default signal strength conditions is the RSCP threshold value of the strongest described RSCP more than or equal to configuration, and the strongest perhaps described RSCP is greater than the RSCP of current service cell.

4. the method for claim 1 is characterized in that, also comprises:

When RNC distributes new Radio Resource for UE in described Target cell,, then discharge the Radio Resource that the Radio Link that goes wrong takies if unappropriated Radio Resource can't satisfy the Radio Resource of UE demand in the Target cell.

5. the method for claim 1 is characterized in that, described default cell update trigger condition comprises: under sub-district-dedicated transmission channel CELL-DCH state, UE receives the timer expiry that starts after physical layer reports the step-out of setting quantity to indicate continuously.

6. the method for claim 1, it is characterized in that, described default cell update trigger condition comprises: under affirmation mode, because the repeating transmission of upstream data bag reaches set point number UE and requires base station node B to obtain to reply after reshuffling the RLC sublayer in the Radio Link control RLC sublayer, perhaps reshuffle and reach set point number RLC sublayer and do not recover.

7. method as claimed in claim 5 is characterized in that, under the CELL-DCH state, UE receives that physical layer reports before the step-out indication of setting quantity continuously, also comprises:

Under the CELL-DCH state, NodeB receives after physical layer is reported the step-out indication of setting quantity continuously and stops downlink.

8. method as claimed in claim 5 is characterized in that, under the CELL-DCH state, UE receives that physical layer reports before the step-out indication of setting quantity continuously, also comprises:

Under affirmation mode, when the repeating transmission of downlink data packet reached set point number in the RLC sublayer, NodeB required RNC to reshuffle the RLC sublayer, reached set point number RLC sublayer and did not recover if reshuffle, and NodeB stops downlink.

9. the cell update system in the TD-SCDMA network is characterized in that, comprising:

User equipment (UE) when being used to confirm to satisfy default cell update trigger condition, according to the measurement result select target sub-district of nearest common frequency measurement and different-frequency measure, and sends cell update message, wherein carries the identification information of Target cell; And after receiving described cell update acknowledge message, insert Target cell according to the described new Radio Resource of wherein indicating;

Radio network controller (RNC) when being used to receive the cell update message of UE transmission, being that UE distributes new Radio Resource in the Target cell of described identification information indication, and returning the cell update acknowledge message to UE.

10. system as claimed in claim 9 is characterized in that,

Described RNC also is used for when the described Target cell Radio Resource new for UE distributes, if unappropriated Radio Resource can't satisfy the Radio Resource of UE demand in the Target cell, then discharges the Radio Resource that the Radio Link that goes wrong takies.

11. system as claimed in claim 9 is characterized in that, also comprises:

Base station node B is used under sub-district-dedicated transmission channel CELL-DCH state, receives after physical layer is reported the step-out indication of setting quantity continuously to stop downlink;

Perhaps, under affirmation mode, when the repeating transmission of downlink data packet reaches set point number in the Radio Link control RLC sublayer, require RNC to reshuffle the RLC sublayer, reach set point number RLC sublayer and do not recover, stop downlink if reshuffle.

12. a subscriber equipment is characterized in that, comprising:

Control unit is when being used to confirm to satisfy default cell update trigger condition, according to the measurement result select target sub-district of nearest common frequency measurement and different-frequency measure;

Transmitting element is used to send cell update message, wherein carries the identification information of Target cell;

Updating block is used for after receiving the cell update acknowledge message, inserts Target cell according to the new Radio Resource that distributes for user equipment (UE) in Target cell of wherein indicating.

13. subscriber equipment as claimed in claim 12 is characterized in that, described control unit comprises storing sub-units, judgment sub-unit and chooser unit, wherein:

Described storing sub-units, be used to store the measurement result of nearest common frequency measurement and different-frequency measure, the measurement result of described common frequency measurement comprises the received signal code power RSCP of each adjacent co-frequency cell, and the measurement result of described different-frequency measure comprises the RSCP of each adjacent alien-frequency district;

Described judgment sub-unit when being used to confirm to satisfy default cell update trigger condition, judges whether RSCP the strongest among the RSCP of each adjacent alien-frequency district satisfies default signal strength conditions, and the output judged result;

Described chooser unit, be used in the judged result of judgment sub-unit output when being, select RSCP is the strongest in each adjacent alien-frequency district sub-district as Target cell, for not the time, select RSCP is the strongest in the adjacent co-frequency cell with each of each adjacent alien-frequency district sub-district in the judged result of judgment sub-unit output as Target cell.

14. subscriber equipment as claimed in claim 13 is characterized in that,

Described judgment sub-unit specifically is used under sub-district-dedicated transmission channel CELL-DCH state, reports the timer expiry of the step-out indication back startup of setting quantity continuously if receive physical layer, then confirms to satisfy default cell update trigger condition.

15. subscriber equipment as claimed in claim 13 is characterized in that,

Described judgment sub-unit, specifically be used under affirmation mode, if because the repeating transmission of upstream data bag reaches set point number and requires base station node B to obtain to reply after reshuffling the RLC sublayer in the Radio Link control RLC sublayer, perhaps reshuffle and reach set point number RLC sublayer and do not recover, then confirm to satisfy default cell update trigger condition.

Images