WO2005096641A1 - Procede de transfert de relais dans un systeme de communication mobile - Google Patents

Procede de transfert de relais dans un systeme de communication mobile Download PDF

Info

Publication number
WO2005096641A1
WO2005096641A1 PCT/CN2005/000442 CN2005000442W WO2005096641A1 WO 2005096641 A1 WO2005096641 A1 WO 2005096641A1 CN 2005000442 W CN2005000442 W CN 2005000442W WO 2005096641 A1 WO2005096641 A1 WO 2005096641A1
Authority
WO
WIPO (PCT)
Prior art keywords
base station
mobile terminal
target base
measurement
handover
Prior art date
Application number
PCT/CN2005/000442
Other languages
English (en)
French (fr)
Inventor
Shihe Li
Desuo Zhou
Hai Bi
Original Assignee
Da Tang Mobile Communications Equipment Co., Ltd.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Da Tang Mobile Communications Equipment Co., Ltd. filed Critical Da Tang Mobile Communications Equipment Co., Ltd.
Publication of WO2005096641A1 publication Critical patent/WO2005096641A1/zh

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
    • H04W52/04—TPC
    • H04W52/38—TPC being performed in particular situations
    • H04W52/40—TPC being performed in particular situations during macro-diversity or soft handoff
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/24—Reselection being triggered by specific parameters
    • H04W36/30—Reselection being triggered by specific parameters by measured or perceived connection quality data
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/24—Reselection being triggered by specific parameters
    • H04W36/30—Reselection being triggered by specific parameters by measured or perceived connection quality data
    • H04W36/302—Reselection being triggered by specific parameters by measured or perceived connection quality data due to low signal strength
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/34—Reselection control
    • H04W36/38—Reselection control by fixed network equipment

Definitions

  • the invention relates to a handover technology of a time division one synchronous code division multiple access (TD-SCDMA) cellular mobile communication system, and particularly relates to a relay switching method for realizing a handover of a TD-SCDMA system.
  • TD-SCDMA time division one synchronous code division multiple access
  • Handover occupies an important position in cellular mobile communication systems.
  • hard handover technology was used, but hard handover will cause information loss during the handover process.
  • the mobile communication system based on the code division multiple access technology uses soft handover technology.
  • the soft handover process does not lose information, does not interrupt communication, and can increase the capacity of the mobile communication system.
  • the soft handover technology only solves the problem of terminal handover between cells or sectors using the same carrier frequency.
  • the hard handover method can still only be used.
  • the soft handover process occupies more communication devices and wireless channels, resulting in a waste of system resources.
  • Relay handover technology maintains the advantage of soft handover without losing information during handover, saves network resources more, and can switch between base stations or sectors using different carrier frequencies. It is an ideal that does not lose information and does not interrupt communication. Handover method.
  • the relay handover technology has been written in the third generation mobile communication standard 3GPP 25.834 as a handover method of the TD-SCDMA system, but the standard only gives a brief description of the relay handover, and does not specify the specific implementation: However, the process leading to the relay switching is still not clear and simple.
  • the open-loop synchronization measurement technology is that the mobile terminal determines the neighboring cells that need to be synchronized and track and maintains and maintains the timing between the pilot signals according to the relative relationship between the pilot signals of the neighboring cells and the serving cell. Relationship technology.
  • the timing for the mobile terminal to start the open-loop synchronous measurement can be determined by the mobile terminal itself, referred to as terminal trigger, or it can be started after receiving a network instruction, referred to as network trigger.
  • the terminal trigger is when the mobile terminal measures the neighboring cell list in the system broadcast information, compares the difference between the pilot signals of these neighboring cells and the serving cell, and selects some neighboring cell base stations from which Open loop synchronization is maintained.
  • the network trigger is that the network determines the cells that need to perform open-loop pre-synchronization, and notifies the mobile terminal by signaling. After receiving the signaling, the mobile terminal measures these cells and measures the cell neighbors based on the measured neighboring cells. Frequency signals, select some neighboring cell base stations and maintain open-loop synchronization with them. Through this open-loop synchronization measurement process, the mobile terminal can obtain and save synchronization information.
  • FIG. 1 illustrates a structure of a TD-SCDMA mobile communication system, which is composed of a core network (CN) 130, multiple radio network controllers (RNC) such as 121, 122, and n base stations. 101, 102, ..., 10n.
  • CN core network
  • RNC radio network controllers
  • the mobile terminal 201 is far away from the base station 101 and the radio wave propagation is fading, and the mobile terminals 202 and 203 move toward the shame station 101 and are closer to the base station 101.
  • the radio wave propagation fading between the base station 101 and the mobile terminals 202 and 203 may be 10 dB to 20 dB smaller than the radio wave propagation fading between the base station 101 and the mobile terminal 201. Since the communication quality between the mobile terminal 201 and the base station 101 may have deteriorated, at this time, in order to ensure the quality of information transmission, the mobile terminal 201 will consider switching to a similar cell, such as a cell covered by the base station 102 or 10n.
  • One handover method is to use hard handover, that is, the mobile terminal 201 first communicates with the base station 101 (referred to as the original base station and also the base station before the handover), and then communicates with the base station 102 (hereinafter referred to as the target base station, which is also the base station after the handover).
  • the main service of the same service is to establish communication.
  • the main disadvantage of this hard handover technology is that it will cause a communication interruption of 100-300ms during the handover process, and the information transmitted during this time will be lost. Dialogue communication is tolerable, but for data communication, This is almost tolerable.
  • Another handover method is to use soft handover, but soft handover needs to use macro diversity in order to perform it. That is, under the condition that the carrier frequencies of the base station 101 and the base station 102 and even the base station 10n are the same, the mobile terminal 201 maintains communication with the base station 101 while It also receives signals from the base station 102, -g- to 10n, which are exactly the same as the signals from the base station 101, and the mobile terminal only changes to send the uplink signal to the target base station when switching between 4 channels.
  • the advantage of soft handover is that it loses information, but occupies a lot of wireless resources. Moreover, soft handover can only be performed between base stations with the same carrier frequency. Otherwise, the cost of mobile terminals will increase significantly. Summary of the invention
  • the invention provides a method for realizing relay switching in a TD-SCDMA mobile communication system. Make full use of the characteristics of open loop power measurement and open loop synchronous measurement to make the relay switching process Incorporating, simple and reliable.
  • a relay switching method in a TD-SCDMA mobile communication system includes mobile terminal measurement, relay switching discrimination, and a relay 4-pole-blade execution process;
  • the mobile terminal measurement includes: The conventional parameters performed by the communication standard and the measurement report are reported to the system;
  • the relay handover determination is to determine a target base station that can be accepted according to the selected handover-decision criterion;
  • the measurement of the mobile terminal further includes: an open-loop power measurement and an open-loop synchronization measurement performed by the mobile terminal on a base station in the cell and a base station in an adjacent region;
  • the execution of the relay switching includes:
  • the system After the system determines a target base station that can be accepted, it sends a physical channel reconfiguration command to the mobile terminal through the original base station, and notifies the terminal of the characteristics of the target base station in the command. The system maintains the wireless link between the mobile terminal and the original base station. At the same time, a wireless link is established between the mobile terminal and the target base station;
  • the system sends the same downlink data to the original base station and the target base station, and simultaneously receives the uplink data of the original base station and the target base station;
  • the mobile terminal receives the downlink data of the original base station, and sends the uplink data to the target base station by using the transmission advance calculated in the open-loop synchronization rule and the transmission power calculated in the open-loop power measurement;
  • the mobile terminal After sending the uplink data to the target base station, the mobile terminal receives the downlink data from the target base station, performs two-way communication with the target base station, and sends a response to the system through the target base station: a physical channel reconfiguration completion response.
  • the system receives the mobile terminal's After the physical channel reconfiguration response is completed, the radio link between the mobile terminal and the original cell base station is released.
  • the method for implementing relay handover in the TD-SCDMA mobile communication system of the present invention includes three processes: mobile terminal measurement, handover discrimination, and handover execution.
  • the mobile terminal i measurement not only the conventional parameters are measured, but also the open-loop power of the neighboring cell base stations will be completed: Open-loop synchronization measurement; there is no obvious difference between the handover discrimination described in the present invention and the conventional handover discrimination method; during the relay handover execution process, the system simultaneously establishes a wireless link between the mobile terminal and the original base station and the target base station, and transmits the same downlink Data and receive uplink data, but choose one of the uplink data of good quality to process and report, and the mobile terminal receives the downlink data from the original base station and uses the open-loop synchronization measurement and open-loop power measurement method to calculate the transmission power and transmission to the target base station In advance, the uplink data is transmitted to the target base station. This process only requires a few radio frames, and then receives the downlink data from the
  • the open-loop power measurement of the mobile station on the neighboring cell base station measures the downlink pilot time slot (DwPTS) signal transmitted by the serving cell base station received by the mobile terminal and the downlink pilot time slot (DwPTS) signal transmitted by the neighboring cell base station. Or measuring the power difference between the primary common control channel (P-CCPCH) pilot signal transmitted by the serving cell base station received by the mobile terminal and the P-CCPCH pilot signal transmitted by the neighboring cell base station.
  • DwPTS downlink pilot time slot
  • DwPTS downlink pilot time slot
  • DwPTS downlink pilot time slot
  • the open-loop synchronous measurement of a mobile station on a neighboring cell base station is to measure the difference between the arrival time of the DwPTS signal transmitted by the neighboring cell base station received by the mobile terminal and the DwPTS signal transmitted by the base station of the original cell, or measure the neighboring cell received by the mobile terminal.
  • the arrival time of the P-CCPCH pilot signal transmitted by the cell base station is different from the arrival time of the P-CCPCH pilot signal transmitted by the original cell base station.
  • the timing for starting the open-loop synchronous measurement and the open-loop power measurement in the mobile terminal can be determined by the mobile terminal itself or can be started after receiving a network instruction, but the implementation of the former method is easier to implement the latter method.
  • the system When the system (RNC) performs a relay handover, it simultaneously sends downlink service data and associated signaling (collectively referred to as downlink data) to the original base station and the target base station, and simultaneously receives uplink service data and associated signaling (collectively referred to as the downstream) from these two base stations. Uplink data), but select one uplink service data with good quality and report along with the signaling processing.
  • the mobile terminal When the mobile terminal performs a relay handover, it receives downlink data from the original base station in a short time, and adopts open-loop synchronization measurement and open-loop power measurement methods to obtain transmission power and transmission advance, and sends uplink data to the target base station. After this time, after receiving the downlink data from the target base station to achieve two-way communication with the target base station, the target base station sends a physical channel reconfiguration completion message to the system to complete the relay handover.
  • the present invention makes full use of the advantage that the TD-SCDMA system is a synchronous CDMA system using a smart antenna and works with multi-slot time division duplexing (TDD).
  • TDD time division duplexing
  • a mobile terminal When a mobile terminal performs a measurement, it can obtain an open-loop connection with a base station in an adjacent cell. The link loss between the radio wave propagation and the radio wave propagation time difference are synchronized with an adjacent base station to be switched in in an open loop manner.
  • the relay handover process it is not necessary to access the target base station through a complicated communication process, so that the relay handover process is very simple without losing information.
  • the simplest mobile terminal that can only receive a time slot signal can also implement relay switching. For example, it can also be implemented when only one downlink time slot and five uplink time slots are configured in a subframe. Said relay switching. Therefore, the technical solution of the present invention is a method for improving and practicalizing the relay switching technology. Brief description of the drawings
  • Figure 1 is a schematic diagram of the TD-SCDMA cellular mobile communication system structure and handover process
  • Figure 2 is a schematic diagram of the mobile terminal measurement during the TD-SCDMA cellular mobile communication system during the relay handover process
  • FIG. 3 is a block diagram of a handover discrimination process in a TD-SCDMA cellular mobile communication system during a relay handover process
  • Figure 4 shows the RC operation during the TD-SCDMA cellular mobile communication system Work flow diagram
  • Figure 5 is a block diagram of the mobile terminal's work flow during a TD-SCDMA cellular mobile communication system during a relay handover.
  • Fig. 6 is a block diagram of a main flow of a baton handover embodiment of a TD-SCDMA cellular mobile communication system. Mode of Carrying Out the Invention
  • the invention discloses a method for performing relay switching in a TD-SCDMA mobile communication system.
  • the base station needs to provide a shaped beam to each active mobile terminal, that is, a mobile terminal that has determined a code channel, to align the mobile terminal.
  • the base station 101 transmits signals to the mobile terminals 201, 202, and 203 using the shaped downlink beams 301, 302, and 303, respectively.
  • the mobile terminal 201 may switch to the base station 102 or the base station 10n.
  • the relay handover process mainly includes three steps: mobile terminal measurement, handover discrimination, and handover execution process. The details are as follows:
  • the measurement is divided into a base station measurement and a mobile terminal measurement.
  • the measurement objects used by the base station equipment of the TD-SCDMA cellular mobile communication system mainly include: A base station with a smart antenna can provide mobile terminal signal incoming wave direction (AOA) and measurement values of the received signal quality of the base station.
  • AOA mobile terminal signal incoming wave direction
  • the mobile terminal measurement refers to that during the communication process, the mobile terminal must complete the measurement tasks specified in the communication standard, that is, the measurement of conventional parameters.
  • the measurement of the conventional parameters includes: periodically measuring various receiving and transmitting parameters of the local cell that is communicating, that is, the serving cell, or performing other measurements of specific parameters according to system requirements when an event occurs (event triggering mode), In addition, various reception and transmission parameters of neighboring cells should be periodically measured or When the event occurs, other measurements of specific parameters are performed according to system requirements.
  • the mobile terminal performs various measurement tasks according to the system requirements and will report the measurement results to the system, that is, the RNC, when it meets the reporting requirements of the measurement report.
  • the method of reporting the measurement report may be a periodic report method or an event-triggered report method, or a combination of a periodic report and an event-triggered report according to the measurement quantity.
  • the report method and measurement object of the mobile terminal measurement report are determined by the RNC.
  • the measurement objects that can be implemented by the mobile terminal equipment in the TD-SCDMA system include: mobile terminal's measurement parameters of the serving cell reflected in the communication standard; mobile terminal's measurement parameters of the neighboring cell reflected in the communication standard; and not reflected in the communication
  • the mobile terminal in the standard is a measurement parameter that is measured according to its own capabilities.
  • the measurement parameters of the serving cell by the mobile terminal include: basic common control channel received signal code power (P-CCPCH RSCP), signal strength of downlink pilot sequence time slot (DwPTS), carrier received signal strength indicator (UTRA carrier RSSI), received signal signal-to-interference ratio (SIR), transmission channel block error rate (Transport channel BLER), transmission power (UE transmitted power) of the mobile terminal, and timing advance (TADV).
  • P-CCPCH RSCP basic common control channel received signal code power
  • DwPTS signal strength of downlink pilot sequence time slot
  • UTRA carrier RSSI carrier received signal strength indicator
  • SIR received signal-to-interference ratio
  • Transport channel BLER Transmission channel block error rate
  • UE transmitted power transmission power
  • TADV timing advance
  • the measurement parameters of the adjacent cell by the mobile terminal include: SFN-SFN observed time difference (type 1, type 2); and the system frame number of the adjacent cell and the serving cell.
  • SFN-CFN observed time difference of the connection frame number of the serving cell and P-CCPCH received signal code power (P-CCPCH RSCP) of the neighboring cell.
  • P-CCPCH RSCP P-CCPCH received signal code power
  • the measurement parameters performed by the mobile terminal include: the power difference between the downlink pilot slot signal of the serving cell and the neighboring cell received by the mobile terminal; the downlink pilot slot signal of the neighboring cell and the downlink pilot signal of the serving cell. Arrival time difference of time slot signal.
  • the method of the present invention mainly uses the above-mentioned mobile terminal> measurement according to the communication standard requirements Parameters and the above two measurement parameters that are not currently specified in the communication standard, that is, the power difference between the mobile terminal receiving the downlink pilot time slot signals of the serving cell and the neighboring cell, and the downlink pilot time slot signals of the neighboring cell and the serving cell.
  • the difference in the time delay of the arrival of the downlink pilot time slot signal is used for relay switching judgment and relay switching.
  • the mobile terminal receives a TD-SCDMA subframe (frame length is 5ms) signal.
  • the second time slot (TS2) of the subframe signal is an uplink time slot for communication with the original base station
  • the sixth time slot (TS6) is the same as the original base station.
  • the downlink time slot for communication, the third time slot (TS3) is an uplink time slot for communication with the target base station, and the fifth time slot (TS5) is a downlink time slot for communication with the target base station.
  • the time when the downlink pilot time slot (DwPTS) of each base station reaches the mobile terminal will be completely determined by the distance between the mobile terminal and the corresponding base station (known electromagnetic waves The propagation rate is 300 m / ys). Because the third-generation mobile communication system uses the 2GHz frequency band, the distance between the base stations cannot be very large (usually within a few kilometers), and the distance between the mobile terminal and the original base station and the target base station will not be different when switching. It is large. Generally, this distance difference does not exceed 1 km. In this way, it is possible to detect DwPTS signals from several nearby base stations in the vicinity of receiving the DwPTS signals transmitted by the original base station.
  • DwPTS downlink pilot time slot
  • the DwPTS signals of different base stations use different codewords, it is possible to obtain the received power P of each DwPTS signal by a conventional method, and use a correlation operation method, that is, to obtain a point multiplication method by using two sequence signals. Time t when each DwPTS signal arrives at the mobile terminal. As shown in FIG.
  • the measurement method of the above measurement parameters is very simple, and sufficient accuracy can be guaranteed under the condition that the communication quality of the mobile terminal can be guaranteed.
  • information from each neighboring base station can be obtained, as shown in Table 1 (taking three neighboring cell base stations as an example), and recorded in the mobile terminal.
  • the RNC After the mobile terminal reports the above-mentioned measurement parameters to the RNC through a measurement report, the RNC will perform a relay switching judgment according to the measurement parameters reported by the mobile terminal.
  • the relay handover determination is performed according to the communication standard, and the initiation and determination of the handover are completed by the RNC. After receiving the measurement report from the mobile terminal, the RNC will start the handover decision process. In addition, the R C may also determine whether the mobile terminal is already in a handover area and is more suitable for handing over to a new cell according to an estimation result of the geographic location of the mobile terminal, and start a handover decision process. ,
  • the handover measurement report uses the event trigger report method
  • the event can be 1G (corresponding to the intra-frequency relative pilot criterion), 2A (corresponding to the inter-frequency relative pilot criterion), 5A (corresponding to the Quality criterion), 6A (corresponding to power criterion), etc.
  • the handover measurement report uses the periodic report method, the decision on which handover criteria is satisfied is done in the RNC.
  • the present invention adopts a method for judging a handover according to a signal level of a downlink pilot time slot and a receiving quality of a mobile terminal, that is, a transmission channel block error rate BLER.
  • the discrimination process is shown in FIG. 3 and includes:
  • Step 300 The RNC receives the measurement report.
  • Step 310 The RNC first determines whether the DwPTS signal level of a neighboring cell base station measured by the mobile terminal is higher than the measured DwPTS level of the base station of the own cell and is higher than a set value.
  • the corresponding event triggering report method is to judge Whether the mobile terminal reports a 1G event, and if so, the neighboring cell base station as a candidate base station, and then step 340 is performed; otherwise, step 320 is performed.
  • the set value described in this step is a value configured by the system according to experience, such as l ⁇ 3dB.
  • this event not only requires that the downlink pilot slot signal strength of the base station in the neighboring cell is greater than the downlink pilot slot signal strength of the base station in the cell, but also requires more than a system set value, indicating the phase
  • the signal strength of the downlink pilot time slot of the base station of the neighboring cell is greater than the signal strength of the downlink pilot time slot of the base station of the cell and exceeds the set value, and then the 1G event report can be triggered.
  • the set value is the system's measurement control command through the 1G event. Configured.
  • Step 320 Check whether the reception quality reported by the mobile terminal, that is, the link quality, that is, whether the received block error rate (BLER) reported by the mobile terminal meets the minimum requirements of the system, and the corresponding event trigger reporting method is to determine whether the mobile terminal reports a 5A event. If the BLER received by the mobile terminal meets the minimum requirements of the system, no processing is performed, and the process returns to step 300 to continue viewing the next measurement report. If the BLER received by the mobile terminal does not meet the minimum requirements, perform step 330.
  • BLER block error rate
  • Step 330 Find out if there is an adjacent cell base station with a received DwPTS signal level higher than the received DwPTS signal level of the own cell base station.
  • the corresponding event trigger report method is to determine whether the mobile terminal reports 6A. In the event, if there is, the found neighboring cell base station is used as a candidate base station, and the candidate base stations are sorted according to the DwPTS signal level from high to low, and then step 340 is performed; if there is no DwPTS signal level than received The neighbouring cell base station with the high DwPTS signal level of the serving cell base station does not perform processing, and returns to step 300 to continue viewing the next measurement report.
  • step 310 Only the DwPTS information of the neighboring cell base station is required.
  • the spear level is greater than the DwPTS signal level of the base station in this cell, such as greater than 0.1 dB, 0.5 dB, and does not need to exceed a certain value.
  • the operation of this step is specifically as follows: ⁇ P is obtained by subtracting the DwPTS signal level of the base station of the neighboring cell and the DwPTS signal level of the serving cell base station. When ⁇ P is greater than 0, then the size of ⁇ P is used to change the neighboring cell from large to small.
  • the base station is determined as the strongest, second strongest, second strongest base station, and so on.
  • Step 340 Check the admission capability of the candidate base station. If there is an adjacent cell base station that can accept, execute step 350 to implement the relay handover; otherwise, the relay handover is unsuccessful and return to step 300 to continue viewing the next measurement report. At this time, the RNC will perform other radio resource management (RRM) operations, including packet scheduling and time slot adjustment.
  • RRM radio resource management
  • step 310 when it is determined in step 310 that it is a 1G event or the DwPTS signal level of a base station in a neighboring cell is found to be much higher than the measured DwPTS level of the base station in this cell, directly check the neighboring cell.
  • the capacity of the base station when it is determined in step 310 that it is a 1G event or the DwPTS signal level of a base station in a neighboring cell is found to be much higher than the measured DwPTS level of the base station in this cell, directly check the neighboring cell. The capacity of the base station.
  • step 350 is performed. If the admission capability of the candidate base station is not acceptable, check the admission capability of the second strongest candidate base station. If the second strongest base station is acceptable, then step 350 is performed to implement relay handover. Otherwise, Continue to query the admission capability of the next strongest base station until all the cell base stations with higher DwPTS signal levels received by the mobile terminal than the received base station DwPTS levels are queried, but all of them cannot be accepted. , The relay switching judgment is unsuccessful, and the process returns to step 300 to continue to view the next measurement report (for tubeization, the process is omitted in the figure).
  • Step 350 Perform a relay switching process of the present invention.
  • the execution of the relay handover according to the present invention is controlled by the RNC, and specific execution entities include: an RNC base station and a mobile terminal, where the base station includes an original base station and a target base station.
  • Step 400 After the RNC completes the handover discrimination shown in FIG. 3 and determines the target base station for the handover, it first obtains synchronization with the transmission network layer between the target base station, including establishing a link with the target base station and allocating resources;
  • Step 410 The RNC sends a physical channel reconfiguration message, that is, a handover command, to the mobile terminal through the original base station link.
  • the physical channel reconfiguration message informs the mobile terminal of the target base station ’s nature, including: the target base station identifier (ID), Parameters such as the radio resources allocated by the uplink and downlink, the transmit power of the target base station, the received power level required by the target base station, and the timing offset required by the target base station for reception;
  • ID target base station identifier
  • Parameters such as the radio resources allocated by the uplink and downlink, the transmit power of the target base station, the received power level required by the target base station, and the timing offset required by the target base station for reception;
  • Step 420 the RNC simultaneously opens two wireless links for the mobile terminal performing the handover, one is a link that maintains communication with the original base station, and the other is a newly established link that communicates with the target base station, and the RNC will send to the After the downlink data of the mobile terminal performing the handover is copied, it is simultaneously sent to the original base station and the target base station through the two uplink links, and the uplink data from the mobile terminal is simultaneously received through the two links.
  • RNC only chooses one of them to receive high-quality business data and report it after processing;
  • the downlink data and uplink data include: downlink, uplink services and signaling; step 430, after performing step 420, starting (setting) a timer T1 after establishing a wireless link between the mobile terminal and the target base station;
  • Steps 440 and 470 When the RNC receives the physical channel reconfiguration complete message sent by the mobile terminal through the target base station, the RNC confirms that the mobile terminal has switched to the target cell, and the RC sends a radio link deletion message to the original cell base station, and terminates the original link to the original cell.
  • the cell base station sends downlink service data to confirm successful handover;
  • Steps 450 and 480 When the RNC receives a message that the physical channel reconfiguration fails through the uplink of the original base station, the RNC confirms the handover failure. At this time, the RNC sends a radio link deletion message to the target base station and terminates the target base station. Sending downlink service data;
  • Steps 460 and 480 when the timer T1 expires, if the RNC has not received the mobile
  • the RC confirms the handover failure.
  • the NC sends a radio link deletion message to the target base station, and at the same time terminates sending downlink service data to the target base station.
  • FIG. 5 shows the operations performed by the mobile terminal during the relay switching process.
  • Step 500 When the mobile terminal receives a physical channel reconfiguration message from the RNC through the original base station, that is, a handover command, the mobile terminal starts to perform a relay handover process.
  • Step 510 The mobile terminal performs open-loop power measurement and open-loop synchronization measurement on the target cell base station, and re-measures the DwPTS signal of the target cell base station.
  • the measurement uses the method shown in FIG. 2 to measure the target base station DwPTS signal amplitude P t and the arrival time t t of the DwPTS i number.
  • the open loop power measurement refers to that the mobile terminal obtains the transmission power P M of the target base station DwPTS signal from the handover command, the received power P R required by the target base station, and the target base station DwPTS signal amplitude P t obtained by the measurement,
  • the open loop determines the transmit power P ⁇ that the mobile terminal should have to the target base station.
  • the calculation formula is as follows:
  • ⁇ is a transmission power increase to ensure that the target base station can correctly receive, for example, 1-3dB
  • P M -P t is the path propagation loss of the mobile terminal to the target base station
  • the open-loop synchronization measurement refers to that the mobile terminal uses the timing advance Ta Q used when it communicates with the original base station, the timing offset ⁇ ⁇ required by the original base station to receive, and the arrival time t 0 of the DwPTS signal of the original base station.
  • the timing offset ⁇ N required by the target base station received in the command and the measured arrival time t t of the DwPTS signal of the target base station are calculated by the following formula.
  • Ta Ta 0 + 2 (t t -1 0 )- ⁇ 0 + ⁇ ⁇
  • step 510 is an optional step, and the purpose is to further improve the reliability of the relay switching according to the present invention.
  • the mobile terminal can directly Using the DwPTS signal amplitude P t and the arrival time t t of the DwPTS signal of the target base station obtained through open-loop power measurement and open-loop synchronization measurement during the mobile terminal measurement process, directly perform step 520 without performing the step described in this step. Re-performing the open-loop power measurement and the open-loop synchronization measurement on the target base station.
  • Step 520 The mobile terminal continues to receive downlink data from the original base station, and at the same time, according to the above-mentioned transmission power P ⁇ of the target base station that the mobile terminal device determined by the open-loop power measurement should be, and the mobile terminal determined by the open-loop synchronous measurement should
  • the transmission timing advance Ta to the target base station transmits uplink data to the target base station.
  • Step 530 The mobile terminal receives downlink data from the target base station, implements closed-loop control and two-way communication with the target base station, and stops communication with the original base station.
  • Step 540 During the two-way communication between the mobile terminal and the target base station, if the mobile terminal cannot correctly receive the downlink data of the target base station, for example, the data from the target base station cannot be received correctly in several radio frames, it is considered that The relay handover fails, the mobile terminal will resume two-way communication with the original base station, and send a physical channel reconfiguration failure message to the RNC.
  • Step 550 During the two-way communication between the mobile terminal and the target base station, if normal communication can be achieved, the mobile terminal will send a physical channel reconfiguration completion message to the RNC through the target base station to complete the relay handover process.
  • the base station in the relay handover can be divided into a target cell base station and an original cell base station, and they respectively perform the following operations during the relay handover process:
  • the operations performed by the target cell base station include:
  • ⁇ downlink service data sent to the RNC, use arbitrary beamforming parameters to send this service data to the mobile terminal; After receiving the uplink service data of the mobile terminal, extract the beamforming information, and send the demodulated uplink service data to the RNC;
  • the downlink service data sent by the RNC After obtaining the beamforming information, if the downlink service data sent by the RNC is received, the downlink service data is encoded according to the extracted beamforming information and sent to the mobile terminal.
  • the original cell base station ⁇ 1 is completely implemented according to the current standard communication protocol. After receiving the radio link deletion message from the RNC, the radio link is deleted, and a radio link deletion response message is returned to the RNC.
  • Another more effective method for tearing down the wireless link is: if no uplink data is received for a period of time and no radio link deletion message from the RNC is received, a radio link failure message is sent to the RNC, and the RNC is requested to recover the link Resources.
  • the target cell base station may also receive the radio link book issued by the RNC! ] Message, at this time, the target cell base station will also delete the radio link and respond to the RNC with a radio link deletion response message. If the target cell base station does not receive uplink data and does not receive a radio link deletion message from the RNC within a continuous period of time, the target cell base station will send a radio link failure message to the RNC, and the RNC is requested to recover the link resources .
  • each logical cell can be treated as one base station, and for each logical cell, an arbitrary beamforming parameter is used to send services to the mobile terminal.
  • Data and after receiving uplink service data of the mobile terminal, extract beamforming information and send downlink data. It should be noted that the process of switching between sectors is exactly the same as that of the above-mentioned base station indirect force switching.
  • the present invention's handling of handover failure is also divided into two aspects: mobile terminal and RC.
  • the RNC handles the handover failure as follows: If before the timer T1 expires, the RC cannot receive a message that the physical channel reconfiguration is successful through the target base station, or that the physical channel reconfiguration failure message has been received from the original base station, the RNC considers that If the handover fails, a radio link deletion message will be sent to the target cell base station for radio resource recovery.
  • the processing process of the mobile terminal for the handover failure is: if the mobile terminal cannot correctly receive the downlink service data sent by the target base station within a certain period of time to realize two-way communication, return to the original configuration, resume communication with the original base station, and simultaneously send to the RNC Send a physical channel configuration failure message; if the mobile terminal switches back to the original configuration and does not receive downlink data from the original base station for a period of time, the handover fails and communication is interrupted.
  • Fig. 6 shows the main flow of the TD-SCDMA cellular mobile communication system implementing relay handover.
  • the figure shows the processing process of the mobile terminal (UE), the original base station (Service NB), the target base station (Target NB), and the serving radio network controller (SRNC) in implementing the relay handover, including:
  • the mobile terminal device maintains open-loop synchronization with the original base station and the target base station, and the RNC makes a handover decision based on the measurements reported by the mobile terminal to determine the target cell;
  • the RNC performs admission control on the target area. If the admission is successful, the radio link (RL) establishment request signaling of the target cell is sent to the target base station;
  • the target base station After receiving the wireless link establishment message, the target base station configures the corresponding link resources. After the configuration is complete, the wireless base station (RL) establishment response message is sent to the RNC. At this time, the original base station, the target base station, and the RNC maintain access. The data transmission of the Link Control Application Part (ALCAP) is established;
  • ALCAP Link Control Application Part
  • the RNC sends downlink data to the original base station and sends the same downlink data to the target base station through the downlink synchronization and uplink synchronization processes with the target base station; Concurrent data to ensure that the mobile terminal can receive successfully; (2) sending a physical channel reconfiguration message to the mobile terminal through the channel of the original cell;
  • the mobile terminal will re-measure according to the designated target base station, and obtain the link loss and arrival time t of the mobile terminal to the target base station through open-loop power measurement and open-loop synchronization measurement.
  • the mobile terminal uses the open loop to the target cell. Transmit uplink information in power measurement and open-loop synchronous measurement mode, and transfer from the original wireless link to the new wireless link;
  • the RNC In order to recover system resources in a timely manner, the RNC sends a "physical channel reconfiguration", and a protection timer T1 needs to be started after signaling;
  • the mobile terminal After the establishment of the two-way communication between the mobile terminal and the target base station is completed, the mobile terminal sends a physical channel reconfiguration completion message to the RNC;
  • the system recycles system resources in a timely manner:
  • the RNC interacts with the target cell through a wireless link deletion request and a delete response message to release the link resources allocated to the target cell;
  • the RNC Due to some abnormal conditions, the RNC has not received any information from the mobile terminal after the T1 timeout. For example, d? N, when the user is suddenly interrupted, the RC will delete the request and delete response with the original cell and the target cell through the wireless link. The interaction of messages releases the link resources allocated to the original cell and the target cell.
  • the RNC may refer to the situation reported by the message, monitor the status of the wireless link, and determine whether to release the resource and when to release the resource with the timer T1.
  • the method of the present invention makes the process of using the relay switching technology in the TD-SCDMA mobile communication system clearer, simpler, and more reliable by making full use of the characteristics of open-loop power measurement and open-loop synchronous measurement and the advantage of using a smart antenna at the base station.
  • the DwPTS signal amplitude P t and the arrival time t t of the DwPTS signal of the serving cell base station and neighboring cell base stations are measured, and they are familiar with the technology in the art. Personnel can understand that in addition to measuring the DwPTS signal, the P-CCPCH signal power and arrival time of the serving base station and neighboring cell base stations can also be measured. In this way, the mobile terminal can also use the P-CCPCH signal power and arrival time.
  • the transmission power and the transmission advance amount for sending uplink data are calculated to realize the relay switching according to the present invention.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Description

TD-SCDMA移动通信系统中的接力切换方法
技术领域
本发明涉及时分一同步码分多址（TD-SCDMA )蜂窝移动通信系统 的切换技术， 特别涉及到一种实现 TD-SCDMA系统越区切换的接力切 换方法。 发明背景
越区切换在蜂窝移动通信系统中占有重要的地位。 在早期的频分多 址和时分多址移动通信系统中， 采用的是硬切换技术， 但是硬切换在切 换过程中将造成信息的丟失。 基于码分多址技术的移动通信系统使用了 软切换技术， 软切换过程不丟失信息、 不中断通信， 还可增加移动通信 系统的容量。 但是， 软切换技术只解决了终端在使用相同载波频率的小 区或扇区间切换的问题， 对于不同载波的基站之间的切换， 仍然只能使 用硬切换方式。 另外， 软切换过程占用了较多的通信设备和无线信道， 造成系统资源的浪费。
在 TD-SCDMA移动通信系统中， 采用了一种更有效的切换技术， 称为接力切换。 接力切换技术保持了软切换在切换时不丟失信息的优 点， 更加节省网络资源， 并且可以在使用不同载波频率的基站或者扇区 之间进行切换， 是一种不丟失信息、 不中断通信的理想越区切换方法。
目前， 接力切换技术已经作为 TD-SCDMA系统的一种越区切换方 法写在第三代移动通信标准 3GPP 25.834 , 但该标准仅仅给出了接力 切换的筒单描述， 并没有规定具体的实现:^法， 导致所述接力切换的过 程仍然不够清晰和筒单。
在接力切换的实现方法方面， 中国专利申请 02155650.4 "—种移动 通信系统中的切换方法" 介绍了一种接力切换的方法， 该方法是在移动 终端向网络端发送测量报告的同时， 通过向目标基站发送特定的训练序 列， 并根据回复的调整信息完成切换准备和同步建立过程， 然后再采用 开环或闭环的方法保持此同步。 在网络端下达切换命令时， 可以直接切 换到所分配的目标基站， 而不需要重新建立接入、 同步的过程。
其中， 所述的开环同步测量技术是移动终端根据相邻小区与服务小 区导频信号之间相对关系， 确定需要进行同步跟踪的相邻小区并与这些 小区保持和维护导频信号之间定时关系的一种技术。 移动终端启动开环 同步测量的时机可以由移动终端自身决定， 简称终端触发， 也可以在接 收到网络指令后启动， 简称网络触发。 所述终端触发就是移动终端在才艮 据系统广播信息中的相邻小区列表进行测量的同时 , 比较这些相邻小区 与服务小区导频信号的差值， 从中选择某些相邻小区基站并与之进行开 环同步保持。 网络触发就是由网络确定需要进行开环预同步的小区， 并 以信令通知移动终端， 移动终端在接收到该信令后， 在对这些小区进行 测量的同时， 根据测量得到的相邻小区导频信号， 选择某些相邻小区基 站并与之进行开环同步保持。 通过此开环同步测量过程， 移动终端可以 获得并保存同步信息。
上述专利申请 02155650.4 虽然描述了在接力切换的过程中获得及 保持预同步的方法, 但没有对实现接力切换方法的完整过程给予说明 , 因而导致在具体实现移动终端的接力切换时， 仍然需要采用硬切换方 式。
参见图 1 , 具体说明如下： 图 1示出一个筒化的 TD-SCDMA移动 通信系统结构， 它由核心网 （CN ) 130, 多个无线网络控制器 （RNC ) 如 121、 122及 n个基站 101、 102、 …、 10η组成。 假设在基站 101覆 盖的小区内有 m个移动终端 201、 202、 203 20m, 其中， 移动终 端 201、 202、 203同时与基站 101通信， 并使用相同的载波频率。 假 殳 移动终端 201向着基站 101覆盖小区的边缘移动， 此时， 移动终端 201 距离基站 101较远， 电波传播衰落较大， 而移动终端 202及 203向着羞 站 101移动， 距离基站 101较近， 基站 101至移动终端 202及 203间^/ 电波传播衰落比基站 101至移动终端 201间的电波传播衰落可能会分 j 小 10dB至 20dB。 由于移动终端 201与基站 101之间的通信质量可能已 经恶化， 此时， 为保证信息传输质量， 移动终端 201将考虑切换到相 小区， 例如基站 102或者 10η所覆盖的小区。
一种切换方法是使用硬切换， 即移动终端 201先和基站 101 (以" F 称原基站， 也是切换前基站） 中断通信， 然后再和基站 102 (以下称 目 标基站， 也是切换后基站）就同一业务建立通信。 该硬切换技术的主 ^ 缺点是在切换过程中将造成 100 - 300ms的通信中断， 必然要丟失这 殳 时间内传输的信息， 对话音通信尚可容忍， 但对数据通信， 这几乎是^ 能容忍的。
另一种切换方法是使用软切换， 但是软切换需要使用宏分集才能疾 施， 即在基站 101与基站 102甚至基站 10η的载波频率相同的条件下， 移动终端 201在与基站 101保持通信的同时， 还接收来自基站 102、 -g- 至 10η的信号， 该信号与来自基站 101的信号完全相同, 移动终端在 4刀 换时改变的仅仅是将上行信号发向目标基站。 显然， 软切换的优点是^ 丟失信息， 但却占用了大量无线资源, 而且， 软切换只能在载波频率 目 同的基站之间进行， 否则， 移动终端的成本将大大增加。 发明内容
本发明给出一种在 TD-SCDMA移动通信系统中实现接力切换的 法。 充分利用开环功率测量和开环同步测量的特性， 使接力切换过程 体化且简单、 可靠。
实现本发明目的的技术方案是这样的： TD-SCDMA移动通信系统中 的一种接力切换方法， 包括移动终端测量、 接力切换判别和接力 4刀换执 行过程； 所述的移动终端测量包括： 按通信标准进行的常规参数铡量， 和向系统上报测量报告； 所述的接力切换判别是根据选择的切换-判决准 则， 确定可以接纳的一个目标基站；
所述的移动终端测量还包括： 移动终端对本小区基站和相邻 区基 站的开环功率测量和开环同步测量；
所述的接力切换执行包括：
A. 系统在确定可以接纳的一个目标基站后，通过原基站向移^终端 发送物理信道重配置命令， 在命令中将目标基站的特性通知终端， 系统 在保持移动终端与原基站之间无线链路的同时， 还在移动终端与 斤述目 标基站之间建立无线链路；
B. 系统向原基站与该目标基站发送相同的下行数据，并同时接收原 基站与该目标基站的上行数据；
C. 移动终端接收原基站的下行数据，并利用在所述开环同步则量中 计算的发射提前量和在所述开环功率测量中计算的发射功率向该目标 基站发送上行数据；
D. 在向目标基站发送上行数据后 ,移动终端接收来自该目标基站的 下行数据， 与目标基站进行双向通信， 并通过目标基站向系统发: 物理 信道重配置完成响应， 系统接收到移动终端的物理信道重配置完 响应 后， 释放移动终端与原小区基站间的无线链路。
本发明的在 TD-SCDMA移动通信系统中实现接力切换的方 ， 包 括移动终端测量、 切换判别和切换执行三个过程。 在移动终端测 i过程 中， 不仅测量常规的参数， 还将完成对相邻小区基站的开环功率:?则量及 开环同步测量； 本发明所述的切换判别和常规的切换判别方法没有明显 区别； 在接力切换执行过程中， 系统同时为移动终端与原基站及目标基 站间建立无线链路， 发射相同的下行数据并接收上行数据， 但选择其中 质量好的一路上行数据处理上报， 移动终端则接收来自原基站的下行数 据并用开环同步测量及开环功率测量方法计算出对目标基站的发射功 率及发射提前量，向目标基站发射上行数据，此过程仅需要几个无线帧， 然后接收来自目标基站的下行数据， 移动终端实现对目标基站的双向通 信后， 向系统发送物理信道重配置完成响应， 完成接力切换。
移动终端对相邻小区基站的开环功率测量， 是测量移动终端所接收 的服务小区基站发射的下行导频时隙（DwPTS )信号与相邻小区基站发 射的下行导频时隙（DwPTS )信号的功率差， 或测量移动终端所接收的 服务小区基站发射的主公共控制信道（P-CCPCH )导频信号与相邻小区 基站发射的 P-CCPCH导频信号的功率差。
移动终端对相邻小区基站的开环同步测量， 是测量移动终端接收到 的相邻小区基站发射的 DwPTS 信号到达时间与原小区基站发射的 DwPTS信号到达时间差，或测量移动终端接收到的相邻小区基站发射的 P-CCPCH导频信号到达时间与原小区基站发射的 P-CCPCH导频信号到 达时间差。
在切换执行过程中,移动终端中启动开环同步测量及开环功率测量 的时机， 可以由移动终端自身决定， 也可以在接收到网络指令后启动， 但前者方法的实现易于后者方法。
系统（RNC )在执行接力切换时， 同时向原基站与目标基站发送下 行业务数据及随路信令（统称下行数据）， 并同时接收来自这两个基站 的上行业务数据及随路信令（统称上行数据）， 但选择质量好的一路上 行业务数据及随路信令处理上报。 移动终端在执行接力切换时， 在一个短时间内接收来自原基站的下 行数据， 而采用开环同步测量及开环功率测量方法获得发射功率及发射 提前量， 向目标基站发送上行数据。 此时间后， 接收来自目标基站的下 行数据， 实现对目标基站的双向通信后， 通过目标基站向系统发送物理 信道重配置完成消息， 完成接力切换。
开始执行接力切换时， 在 RNC设置的定时器 T1超时时仍未接收到 移动终端通过目标基站发送的物理信道重配置完成消息时， 表明接力切 换失败， 移动终端切换回原基站， 继续与原基站通信。
本发明充分利用了 TD-SCDMA 系统是一个使用了智能天线的同步 CDMA系统， 并用多时隙时分双工（TDD )工作的优点， 移动终端在进 行测量时， 可以开环获得与相邻小区基站之间电波传播的链路损耗及电 波传播时间差值， 并用开环方式和邻近待切换进入的基站实现同步。 在 切换过程中， 不需要通过复杂的通信过程对目标基站进行接入， 使接力 切换过程非常筒单又不丟失信息。 而且一个最简单的、 仅仅能接收一个 时隙信号的移动终端也可以实现接力切换， 例如， 在一个子帧中只配置 了 1个下行时隙、 5个上行时隙的情况下也可以实现所述接力切换。 因 而， 本发明的技术方案是对接力切换技术的完善化和实用化方法。 附图简要说明
图 1是 TD-SCDMA蜂窝移动通信系统结构及越区切换过程示意图； 图 2是 TD-SCDMA蜂窝移动通信系统在接力切换过程中的移动终 端测量示意图；
图 3是 TD-SCDMA蜂窝移动通信系统在接力切换过程中的切换判 别过程框图；
图 4是 TD-SCDMA蜂窝移动通信系统在接力切换过程中 R C的工 作流程框图；
图 5是 TD-SCDMA蜂窝移动通信系统在接力切换过程中移动终端 的工作流程框图。
图 6是 TD-SCDMA蜂窝移动通信系统的接力切换实施例主流程框 图。 实施本发明的方式
本发明公开的是一种在 TD-SCDMA移动通信系统中进行接力切换 的方法。 在 TD-SCDMA移动通信系统中， 基站需要对每一个激活的移 动终端， 即已经确定了码道的移动终端， 提供一个赋形波束以对准此移 动终端。 如图 1中， 基站 101分别向移动终端 201、 202及 203使用赋 形的下行波束 301、 302、 303发射信号。 当移动终端 201移动到离基站 101比较远, 而离基站 102或 10η比较近时， 为保证通信质量， 移动终 端 201将可能切换到基站 102或者基站 10n。
本发明所述的接力切换过程主要包括三个步驟： 移动终端测量、 切 换判别和切换执行过程。 具体说明如下：
根据 3GPP协议规定， 所述测量分为基站测量和移动终端测量。 其中， TD-SCDMA蜂窝移动通信系统的基站设备采用的测量对象主 要包括： 具有智能天线的基站可以提供移动终端信号来波方向 （AOA ) 及基站接收信号质量的测量值。
而移动终端测量是指移动终端在通信过程中， 必须完成通信标准规 定的测量任务， 即对常规参数的测量。 所述常规参数的测量包括： 对正 在通信的本小区， 即服务小区的各种接收与发射参数进行周期性测量， 或者在事件发生时（事件触发方式）按系统要求进行特定参数的其他测 量， 此外， 还应当对相邻小区的各种接收与发射参数进行周期性测量或 者在事件发生时按系统要求进行特定参数的其他测量。
移动终端在通信过程中， 按照系统要求执行各种测量任务后， 将在 满足测量报告的上报要求时， 将测量结果报告给系统， 即 RNC。 上报测 量报告的方式可以采用周期报告方式或者事件触发报告方式， 也可以根 据测量量的不同采用周期报告与事件触发报告结合的方式。 移动终端测 量报告的报告方式和测量对象都由 RNC决定。
TD-SCDMA系统中移动终端设备可以实现的测量对象包括：体现在 通信标准中的移动终端对服务小区的测量参数； 体现在通信标准中的移 动终端对相邻小区的测量参数； 和未体现在通信标准中的移动终端才艮据 自身能力所进行测量的测量参数。
其中， 所述的移动终端对服务小区的测量参数包括： 基本公共控制 信道接收信号码功率（P-CCPCH RSCP )、 下行导频序列时隙 （DwPTS ) 的信号强度、 载波接收信号强度指示（UTRA carrier RSSI )、接收信号信 干比 （SIR )、 传输信道误块率（Transport channel BLER )、 移动终端的 发射功率 ( UE transmitted power )、 和定时提前量 ( Timing Advance, TADV )。
所述的移动终端对相邻小区的测量参数包括： 相邻小区与服务小区 的系统帧号观察时间差（ SFN-SFN observed time difference ( type 1 , type 2 ) ) ; 相邻小区的系统帧号与服务小区的连接帧号的观察时间差 ( SFN-CFN observed time difference );以及相邻小区的 P-CCPCH接收信 号码功率 （P-CCPCH RSCP )。
所述的移动终端根据自身的能力进行的测量参数包括： 移动终端接 收的服务小区与相邻小区下行导频时隙信号的功率差； 相邻小区下行导 频时隙信号与服务小区下行导频时隙信号的到达时延差。
本发明所述的方法主要使用上述移动终端 >据通信标准要求的测量 参数以及上述在通信标准中目前还没有规定的两项测量参数， 即移动终 端接收服务小区与相邻小区下行导频时隙信号的功率差， 和相邻小区下 行导频时隙信号与服务小区下行导频时隙信号的到达时延差进行接力 切换判别及接力切换。
这两种测量参数的测量方法如图 2 所示。 移动终端接收到一个 TD-SCDMA子帧 (帧长为 5ms )信号， 该子帧信号第 2时隙 （TS2 )为 与原基站通信的上行时隙， 第 6时隙 （TS6 ) 为与原基站通信的下行时 隙， 第 3时隙 （TS3 )为与目标基站通信的上行时隙， 第 5时隙 （TS5 ) 为与目标基站通信的下行时隙。
由于在此系统中， 所有基站都是严格保持同步的， 则每个基站的下 行导频时隙 ( DwPTS )到达移动终端的时间将完全由移动终端与各相应 基站间的距离决定（已知电磁波的传播速率为 300米 / y s )。 由于第三代 移动通信系统使用 2GHz频段, 基站之间距离不可能很大 (通常在几公 里以内）， 而且在切换时， 移动终端与原基站、 目标基站两个基站间的 距离的差别不会 4艮大， 通常， 此距离差不会超过 1公里。 这样就可能在 接收原基站发射的 DwPTS 信号附近， 检测到来自附近几个基站的 DwPTS信号。 另外， 由于不同基站的 DwPTS信号使用的码字不相同， 这样就可以用常规方法获得每个 DwPTS信号的接收功率 P, 并用求相 关的运算方法， 即用两个序列信号作点乘的方法获得各个 DwPTS信号 到达移动终端的时间 t。 如图 2所示， 经过常规方法及求相关运算的方 法， 计算得到： 来自服务小区基站 0的 DwPTS信号到达移动终端的时 间 to,接收的 DwPTS信号幅度（电平）PQ;来自相邻小区基站 1的 DwPTS 信号到达移动终端的时间 t 接收的 DwPTS信号幅度（电平） 来自 相邻小区基站 2的 DwPTS信号到达移动终端的时间 t2, 接收的 DwPTS 信号幅度（电平） P2; 以及来自相邻小区基站 3的 DwPTS信号到达移 动终端的时间 t3, 接收的 DwPTS信号幅度（电平） P3。
上述测量参数的测量方法非常筒单， 而且， 在移动终端通信质量可 以保证的条件下也可以保证足够的精确度。 通过此测量， 可以获得来自 各相邻基站的信息， 如表 1所示（以 3个相邻小区基站为例）， 并在移 动终端内记录。
Figure imgf000012_0002
Figure imgf000012_0001
当移动终端将上述测量参数通过测量报告上报给 RNC之后， RNC 将根据移动终端上报的测量参数进行接力切换判别。
所述的接力切换判别是根据通信标准进行的 , 切换的发起与判别都 由 RNC完成。 RNC接收到移动终端上艮的测量报告后， 将启动切换判 决过程。 此外， R C也可以根据对移动终端所在地理位置的估计结果判 定其是否已经处于切换区且更适合于切换到新的小区而启动切换判决 过程。 、
根据 3GPP 25.834协议规定， 如果切换测量报告采用的是事件触发 报告方式, 则事件可以是 1G (对应于频内相对导频准则 )、 2A (对应于 频间相对导频准则）、 5A (对应于质量准则）、 6A (对应于功率准则）等。 如果切换测量报告采用的是周期报告方式， 则满足何种切换准则的判决 是在 RNC中完成的。
本发明采用的是根据下行导频时隙信号电平及移动终端接收质量， 即传输信道误块率 BLER进行切换判别的方法。 所述判别过程如图 3所 示， 包括：
步骤 300, RNC接收测量报告。 步骤 310, RNC 首先确定移动终端测量到的一个相邻小区基站的 DwPTS信号电平是否比测量到的本小区基站的 DwPTS电平高， 且高出 设定值， 对应事件触发报告方式， 就是判断移动终端是否上报 1G事件， 如果是则将该相邻小区基站作为候选基站， 然后执行步骤 340; 否则， 执行步骤 320。
需要说明的是， 该步骤所述的设定值为系统根据经验配置的值， 如 l ~ 3dB。 另外， 可以看出， 对应 1G事件， 该事件不只要求相邻小区基 站的下行导频时隙信号强度大于本小区基站的下行导频时隙信号强度， 还要求超过一个系统设定值， 表示相邻小区基站的下行导频时隙信号强 度大于本小区基站的下行导频时隙信号强度且超过该设定值的时候， 才 能触发 1G事件上报,该设定值是系统通过 1G事件测量控制命令配置的。
步骤 320, 查看移动终端上报的接收质量， 即链路质量， 也就是移 动终端上报的接收误块率 （BLER )是否达到系统的最低要求， 对应事 件触发报告方式， 就是判断移动终端是否上报 5A事件， 如果移动终端 接收的 BLER达到系统的最低要求， 则不作处理， 返回步骤 300, 继续 查看下一次测量报告； 如果移动终端接收的 BLER没有达到最低要求， 则执行步骤 330。
步骤 330,查找是否有接收到的相邻小区基站的 DwPTS信号电平比 接收到的本小区基站的 DwPTS信号电平高的相邻小区基站， 对应事件 触发报告方式， 就是判断移动终端是否上报 6A事件， 如果有， 则将查 找到的相邻小区基站作为候选基站， 并按照 DwPTS信号电平从高到低 的顺序将所述候选基站排序， 然后执行步骤 340; 如果没有 DwPTS信号 电平比接收到的服务小区基站的 DwPTS信号电平高的相邻小区基站， 也不作处理， 返回步骤 300, 继续查看下一次测量报告。
本步骤与步驟 310的区别是： 仅仅要求相邻小区基站的 DwPTS信 矛电平大于本小区基站的 DwPTS信号电平， 如大于 0.1 dB 、 0.5 dB, 而不要求超过一定的数值。 本步骤操作具体为： 通过对相邻小区基站的 DwPTS信号电平与服务小区基站的 DwPTS信号电平作减法求得 ΔΡ, 当 ΔΡ大于 0时， 再按 ΔΡ的大小， 由大到小将相邻小区基站分别确定为最 强、 次强、 次次强基站等。
步驟 340, 查看候选基站的接纳能力， 若有相邻小区基站可以接纳， 即执行步骤 350, 实施接力切换； 否则， 接力切换判别不成功， 返回步 聚 300， 继续查看下一次测量报告。 此时， RNC将执行其他无线资源管 理 （RRM )操作， 包括包调度、 时隙调整等。
在本步驟中， 当在步骤 310中确定为 1G事件或查找到某个相邻小 区基站的 DwPTS信号电平比测量到的本小区基站的 DwPTS电平高很多 H , 则直接查看该相邻小区基站的接纳能力。
如果是经过步骤 320、 330判断出移动终端接收的 BLER没有达到 最低要求且存在最强、 次强、 次次强的候选基站等时， RNC将立即查看 移动终端所接收到的 DwPTS信号电平最高的候选基站的接纳能力， 若 可以接纳， 则执行步骤 350, 如果不能接纳， 则查看所述次强候选基站 的接纳能力， 若次强基站可以接纳， 即执行步驟 350, 实施接力切换， 否则， 继续查询次次强基站的接纳能力, 直至移动终端所接收到的相邻 小区基站 DwPTS信号电平比接收到的本小区基站 DwPTS电平高的小区 基站均都查询到， 但却均不能接纳时， 则接力切换判别不成功， 返回步 骤 300继续查看下一次测量报告（为筒化， 图中省略了该过程）。
步骤 350, 执行本发明的接力切换过程。
本发明所述接力切换的执行由 RNC控制， 具体的执行实体包括: RNC 基站以及移动终端， 其中， 基站包括原基站与目标基站。
RNC在接力切换过程中执行的操作如图 4所示。 步骤 400， RNC在完成图 3所示的切换判别， 确定切换的目标基站 后， 首先取得与目标基站间传输网络层的同步， 包括建立与目标基站间 的链路和分配资源；
步骤 410, RNC通过原基站链路， 向移动终端发送物理信道重配置 消息， 即切换命令， 在此物理信道重配置消息中通知移动终端目标基站 的恃性， 包括： 目标基站标识 （ID )、 上行和下行链路所分配的无线资 源、 目标基站的发射功率、 目标基站要求的接收功率电平以及目标基站 接收所需要的定时偏差等等参数；
步骤 420, RNC为执行切换的移动终端同时开通了两条无线链路， 一条是保持的与原基站通信的链路， 另一条是新建立的与目标基站通信 的链路， RNC将发向该执行切换的移动终端的下行数据复制后同时通过 上迷两条链路发送给原基站和目标基站， 并同时通过此两条链路接收来 自移动终端的上行数据。 但 RNC只选择其中一路接收质量好的上行业 务数据， 经处理后上报；
其中， 所述下行数据及上行数据包括： 下行、 上行业务及信令； 步骤 430,在执行完步骤 420、移动终端与目标基站间建立起无线链 路后启动 （设定）定时器 T1;
步骤 440、 470, 当 RNC接收到移动终端通过目标基站发送的物理 信道重配置完成消息后， RNC 即确认移动终端已经切换到目标小区， R C将向原小区基站发送无线链路删除消息，同时终止向原小区基站发 送下行业务数据， 确认切换成功;
步骤 450、 480, 当 RNC通过原基站的上行链路接收到物理信道重 配置失败的消息后， RNC即确认切换失败， 此时 RNC将向目标基站发 送无线链路删除消息， 同时终止向目标基站发送下行业务数据；
步骤 460、 480, 在定时器 T1时间超时时， 若 RNC还未接收到移动 终端通过目标基站发来的物理信道重配置完成消息， 则 R C 即确认切 换失败， 此时 ： NC将向目标基站发送无线链路删除消息， 同时终止向 目标基站发送下行业务数据。
移动终端在接力切换过程中执行的操作如图 5所示。
步驟 500, 当移动终端通过原基站接收到 RNC发来的物理信道重配 置消息， 即切换命令后， 开始执行接力切换过程。
步骤 510, 移动终端对目标小区基站实行开环功率测量和开环同步 测量， 重新测量目标小区基站的 DwPTS信号。
所述测量采用如图 2所示的方法， 测量目标基站 DwPTS信号幅度 Pt及 DwPTS i 号的到达时间 tt。
所述开环功率测量是指， 移动终端根据从切换命令中获得目标基站 DwPTS信号的发射功率 PM, 目标基站所需要的接收功率 PR, 以及通过 测量得到的目标基站 DwPTS信号幅度 Pt, 开环确定移动终端应有的对 目标基站的发射功率 Ρτ, 计算公式如下：
Figure imgf000016_0001
其中， △为一个保证目标基站能正确接收的发射功率增量， 例如， 取 1 - 3dB; PM - Pt为移动终端到达目标基站的路径传播损耗
所述开环同步测量是指， 移动终端根据自身与原基站通信时所使用 的定时提前量 TaQ, 原基站接收所需要的定时偏差 δ ο, 原基站 DwPTS 信号的到达时间 t0, 从切换命令中获得的目标基站接收所需要的定时偏 差 δ N, 以及测量得到的目标基站 DwPTS信号的到达时间 tt, 通过下述 公式计算出开环同步移动终端应向目标基站的发射提前量 Ta:
Ta = Ta0 + 2(tt - 10) - δ 0 + δ Ν
需要说明的是， 上述步驟 510是一个可选步骤， 目的是进一步提高 本发明所述接力切换的可靠性。 在无线环境较好时， 移动终端可以直接 使用在所述移动终端测量过程中通过开环功率测量和开环同步测量得 到的目标基站的 DwPTS信号幅度 Pt及 DwPTS信号的到达时间 tt,直接 执行步骤 520, 而无需执行本步骤所述的对目标基站重新进行所述开环 功率测量和开环同步测量。
步驟 520， 移动终端继续从原基站接收下行数据， 同时， 根据上述 由开环功率测量确定的移动终端设备应有的对目标基站的发射功率 Ρτ, 和由开环同步测量确定的移动终端应向目标基站的发射定时提前量 Ta, 向目标基站发射上行数据。
步驟 530, 移动终端从目标基站接收下行数据， 与目标基站间实现 闭环控制和双向通信， 并停止和原基站的通信。
步驟 540, 在上述移动终端与目标基站进行双向通信的过程中， 若 移动终端不能够正确接收目标基站的下行数据， 例如在几个无线帧内均 不能够正确接收来自目标基站的数据， 则认为接力切换失败， 移动终端 将恢复与原基站间的双向通信， 并向 RNC发送物理信道重配置失败消 白
步骤 550, 在上述移动终端与目标基站进行双向通信的过程中， 若 能够实现正常的 ^又向通信， 移动终端将通过目标基站向 RNC发送物理 信道重配置完成消息， 完成接力切换过程。
所述接力切换中的基站， 可以分为目标小区基站和原小区基站， 它 们在接力切换过程中分别执行如下操作：
目标小区基站执行的操作包括：
在接收到 RNC发来的无线链路建立消息后， 配置相应的链路资源， 并在配置完成后， 组织无线链路建立响应消息发送到 RNC;
此时， 如果^：到 RNC发来的下行业务数据， 则用任意的波束赋形 参数， 向移动终端发送此业务数据; 在接收到移动终端的上行业务数据后， 提取波束赋形信息， 并将解 调后的上行业务数据发向 RNC;
在获得波束赋形信息后， 如果再接收到 RNC发来的下行业务数据， 则按照提取的波束赋形信息 , 将下行业务数据编码后发送给所述移动终 端。
原小区基站^ 1寻完全按照目前的标准通信协议执行， 在接收到 RNC 发来的无线链路删除消息后， 删除无线链路， 并向 RNC 回应无线链路 删除响应消息。
另一种更有效的拆除无线链路的方法是： 如果连续一段时间没有接 收到上行数据也没有收到 RNC的无线链路删除消息， 则向 RNC发送无 线链路失败消息， 请 RNC回收链路资源。
如果所述接力切换失败， 所述目标小区基站也可能会接收到 RNC 下发的无线链路册！]除消息，此时，所述目标小区基站也将删除无线链路， 并向 RNC 回应无线链路删除响应消息。 如果在连续一段时间内所述目 标小区基站没有接收到上行数据也没有收到 RNC的无线链路删除消息， 则该目标小区基占将向 RNC发送无线链路失败消息， 请 RNC回收链路 资源。
如果基站使用了扇区天线， 一个基站会覆盖多个逻辑小区， 则可将 每个逻辑小区当作一个基站来看待， 针对每一个逻辑小区， 用任意的波 束赋形参数， 向移动终端发送业务数据， 并在接收到该移动终端的上行 业务数据后， 提取波束赋形信息， 并发送下行数据。 需要说明的是， 在 各扇区之间的切换与上述基站间接力切换的过程是完全相同的。
根据目前的通信标准， 切换是否失败仅能由 RNC 进行判断， 基站 只负责切换成功与失败过程的执行和对无线链路质量的监测。 因此， 本 发明对切换失败的处理也分为移动终端和 R C两方面。 RNC对切换失败的处理过程是： 如果在定时器 T1超时前， R C不 能通过目标基站收到物理信道重配置成功的消息， 或者已经从原基站收 到物理信道重配置失败的消息， 则 RNC认为切换失败， 将向目标小区 基站发送无线链路删除消息， 进行无线资源回收。
移动终端对切换失败的处理过程是： 如果移动终端在一定的时间内 不能正确接收到目标基站发来的下行业务数据， 实现双向通信， 则返回 原来的配置， 恢复与原基站通信， 同时向 RNC发送物理信道配置失败 消息； 如果移动终端切换回原来的配置且持续一段时间也没有收到原基 站的下行数据时， 则切换失败， 通信中断。
参见图 6,图 6示出 TD-SCDMA蜂窝移动通信系统实施接力切换的 主流程。 该图体现出移动终端 （UE ), 原基站（Service NB )、 目标基站 ( Target NB )和服务无线网络控制器 （ SRNC )在实施接力切换中的处 理过程， 包括：
1. 移动终端设备与原基站及目标基站间保持开环同步， RNC根据 移动终端上报的测量 4艮告进行切换判决， 确定目标小区；
2. RNC对目标'卜区进行接纳控制， 如果接纳成功， 则组织目标小区 的无线链路 ( RL )建立请求信令发往目标基站；
3. 目标基站收到无线链路建立消息后， 配置相应链路资源， 配置完 成后组织无线链路（ RL )建立响应消息发往 RNC, 此时， 原基站、 目 标基站与 RNC 间保持接入链路控制应用部分（ALCAP, Access Link Control Application Part ) 的数据传输 载建立；
4. RNC收到目标基站的无线链路建立响应消息后：
( 1 ) RNC通过与目标基站间的下行链路同步与上行链路同步过程， 在给原基站发送下行教据的同时也给目标基站发送相同的下行数据； 在 一段时间内两条链路上并发数据， 以保证移动终端能够成功接收； ( 2 )通过原小区的信道向移动终端发送物理信道重配置消息；
( 3 )移动终端将根据指定的目标基站， 重新进行测量， 并通过开环 功率测量和开环同步测量获得移动终端至此目标基站的链路损耗及到 达时间 t， 移动终端向目标小区用开环功率测量和开环同步测量方式发 射上行信息， 从原无线链路转到新无线链路上；
为了适时回收系统资源， RNC在发出 "物理信道重配置，，信令后需 要启动保护定时器 T1;
( 4 )在移动终端与目标基站的双向通信建立完成后， 移动终端向 RNC发送物理信道重配置完成消息；
5. 系统适时回收系统资源：
( 1 )如杲切换成功且收到物理信道重配置完成消息， 则 R C与原 小区通过无线链路删除请求及删除响应消息的交互， 释放配置给原小区 的链路资源；
( 2 )如果切换失败且收到物理信道重配置失败消息， 则 RNC与目 标小区通过无线链路删除请求及删除响应消息的交互， 释放配置给目标 小区的链路资源；
( 3 ) 由于某种异常情况 RNC在 T1超时之后仍未收到移动终端的 任何信息， 例 d?n当用户突然中断， 则 R C将与原小区和目标小区通过 无线链路删除请求及删除响应消息的交互， 释放配置给原小区和目标小 区的链路资源。
( 4 )如果在一条链路上在一段时间内无法收到移动终端的信息，则 原基站或目标基站会向 RNC报告 "无线链路失败"。 RNC可以参考该消 息上报的情况， 监测无线链路状态， 并结合定时器 T1 判断是否要幹放 以及何时释放资源。
上述流程图中， 用实线表示在正常情况下执行的信令， 用虚线表示 可能发生的信令。
本发明方法通过充分利用开环功率测量和开环同步测量的特性及基 站使用智能天线的优势， 使 TD-SCDMA移动通信系统中使用接力切换 技术的过程更清晰、 更简单， 也更可靠。
在本发明所述开环功率测量和开环同步测量的过程中， 是对服务小 区基站和相邻小区基站的 DwPTS信号幅度 Pt及 DwPTS信号的到达时 间 tt进行测量， 熟悉本领域的技术人员可以理解， 除了可以对 DwPTS 信号进行测量外， 还可以对服务基站和相邻小区基站的 P-CCPCH信号 功率及到达时间进行测量， 这样， 移动终端同样可以根据 P-CCPCH信 号功率及到达时间计算得到发送上行数据的发射功率以及发射提前量， 实现本发明所述的接力切换。

Claims

权利要求书
1、 TD-SCDMA移动通信系统中的接力切换方法， 包括： 移动终端 测量、 接力切换判別和接力切换执行过程； 所述的移动终端测量包括： 按标准进行的常规參数测量， 以及向系统上报测量报告； 所述的接力切 换判别是根据选择的切换判决准则， 确定可以接纳的一个目标基站； 其特征在于， 所述移动终端测量还包括： 移动终端对服务小区基站 和相邻小区基站的开环功率测量和开环同步测量；
所述接力切换执行包括：
A. 系统在确定可以接纳的一个目标基站后，通过原基站向移动终端 发送物理信道重配置命令， 在命令中将目标基站的特性通知移动终端， 系统在保持移动终端与原基站之间无线链路的同时 , 还在移动终端与所 述目标基站之间建立无线链路；
B. 系统向所述原基站及目标基站发送相同的下行数据，并同时接收 原基站与该目标基沾的上行数据；
C. 移动终端接 <]丈原基站的下行数据，并利用在所述开环同步测量中 计算的发射提前量及所述开环功率测量中计算的发射功率向所述目标 基站发送上行数据；
D. 移动终端接丈来自该目标基站的下行数据，与目标基站实现双向 通信后， 通过目标基站向系统发送物理信道重配置完成响应， 系统接收 到所述物理信道重己置完成响应后， 释放移动终端与原小区基站间的无 线链路。
2、 根据权利要求 1所述的 TD-SCDMA移动通信系统中的接力切 换方法， 其特征在于， 所述的切换判别是系统根据接收到的、 移动终端 以周期报告方式上 4艮或以事件触发报告方式上报的测量报告启动的。
3、根据权利要求 1所述的 TD-SCDMA移动通信系统中的接力切换 方法， 其特征在于， 所 的切换判别是系统才艮据对移动终端所在地理位 置的估计结果判定移动终端已经处于切换区且更适合于切换到新的小 区时启动的。
4、根据权利要求 1所述的 TD-SCDMA移动通信系统中的接力切换 方法， 其特征在于， 所 的切换判别为系统根据相邻小区基站发射的下 行导引时隙信号电平及移动终端接收质量判定移动终端需切换到的目 标基站。
5、根据权利要求 4所述的 TD-SCDMA移动通信系统中的接力切换 方法， 其特征在于： 所 根据相邻小区基站发射的下行导引时隙信号电 平及移动终端接收质量^ 1定移动终端需切换到的目标基站包括：
a. 系统分析测量报告；
b. 当移动终端测量到相邻小区基站的下行导频时隙信号电平高于 测量到的原基站的下行导频时隙信号电平且大于设定值时， 将该相邻小 区基站作为候选基站， 然后执行步骤 e; 否则， 执行步骤 c;
c 判断移动终端接收的误块率是否达到最低要求， 如果是， 返回步 骤 a; 否则， 执行步骤 d;
d. 查找是否有相邻小区基站的下行导频时隙信号电平高于原基站 的下行导频时隙信号电 ， 如果有， 则将查找到的相邻小区基站作为候 选基站， 然后执行步骤 e; 否则， 返回步骤 a;
e.依次查看所述候选基站的接纳能力 , 如果存在能够接纳该移动终 端的候选基站，则将该基站作为该移动终端需切换到的目标基站;否则， 返回步骤&。
6、根据权利要求 1所述的 TD-SCDMA移动通信系统中的接力切换 方法， 其特征在于， 所逸的开环功率测量包括： 移动终端对所接收的服 务小区基站发射的下行 频时隙信号功率的测量， 和对相邻小区基站发 射的下行导频时隙信号功率的测量； 所述的开环同步测量包括： 移动终 端对服务小区基站发射的下行导频时隙信号到达时间的测量， 和对相邻 小区基站发射的下行导频时隙信号到达时间的测量。
7、根据权利要求 1所迷的 TD-SCDMA移动通信系统中的接力切换 方法， 其特征在于， 所述的开环^率测量包括： 移动终端对所接收的服 务小区基站发射的主公共控制信道导频信号功率的测量， 和对相邻小区 基站发射的主公共控制信道导频信号功率的测量； 所述的开环同步测量 包括： 移动终端对服务小区基站发射的主公共控制信道导频信号到达时 间的测量， 和对相邻小区基站发射的主公共控制信道导频信号到达时间 的测量。
8、才艮据权利要求 1所述的 TD-SCDMA移动通信系统中的接力切换 方法， 其特征在于， 所述目标基站特性包括： 目标基站标识、 上行和下 行链路所分配的无线资源、 目标基站的发射功率、 目标基站要求的接收 功率及目标基站接收所需要的定时偏差。
9、根据权利要求 1所述的 TD-SCDMA移动通信系统中的一种接力 切换方法， 其特征在于， 步骤 C所述移动终端利用在所述开环同步测量 中计算的发射提前量及所述开环功率测量中计算的发射功率向所述目 标基站发送上行数据进一步包括：
C1. 移动终端重新测量目标基站的下行导频时隙信号幅度 Pt及下行 导频时隙信号的到达时间 t1 ;
C2. 据式 PT = PR + PM - Pt—△开环确定移动终端应有的对目标基 站的发射功率 PT, PR是从物理信道重配置消息中获取的目标基站所需要 的接收功率， PM是从物理信道重國 置消息中获取的目标基站下行导频时 隙信号的发射功率， △是保证 标基站能正确接收的发射功率增量；
C3. 根据式 Ta = Tao + 2(tt - 10) - δ 0 + δ Ν开环确定移动终端向目标 基站的发射提前量 Ta, Tao是移动终端与原基站通信时所使用的发射提 前量， δ ο是原基站接收所需要的定时偏差， δ ΝΑ从物理信道重配置消 息中获取的目标基站接收所需要的定时偏差， tQ是测量得到的原基站下 行导频时隙信号的到达时间。
10、 根据权利要求 9所述的 TD-SCDMA移动通信系统中的接力切 换方法， 其特征在于： 所述步驟 C 1 中， 所述的移动终端重新测量目标 基站的下行导频时隙信号幅度 Pt及下行导频时隙信号的到达时间 t! , 该 过程由移动终端自身决定启动， 或在移动终端接收到系统发送的指令后 启动。
11、 根据权利要求 9所述的 TD-SCDMA移动通信系统中的接力切 换方法， 其特征在于， 所述步骤 C2 中， 所述的保证目标基站能正确接 收的发射功率增量 Δ取 1 - 3dB。
12、 根据权利要求 1所述的 TD-SCDMA移动通信系统中的接力切 换方法， 其特征在于，
所述步骤 A中，所述的系统通过原基站向移动终端发送物理信道重 配置命令时， 还启动一定时器；
所述步骤 D进一步包括： 在所述的定时器超时时， 仍未收到移动终 端的任何信息时， 系统发出信令， 释放为原基站与目标基站配置无线链 路。
13、 根据权利要求 1所述的 TD-SCDMA移动通信系统中的接力切 换方法， 其特征在于： 所述步骤 D进一步包括， 在基站与目标基站间不 能进行双向通信， 或在接收到原基站发出的物理信道重配置失败的信令 时， 系统发出信令， 释放为目标基站配置的无线链路
14、 根据权利要求 1所述的 TD-SCDMA移动通信系统中的接力切 换方法， 其特征在于， 所述步骤 D进一步包括： 在所述移动终端与原基 站或目标基站之间的无线链路上， 原基站 目标基站在一段时间内没有 接收到移 终端的信息， 将向系统报告无幾链路失败， 系统参考该消息 上报的情 监测该无线链路状态， 判断是否释放移动终端与原基站或 目标基站之间的无线链路及确定何时释放所述的无线链路。
PCT/CN2005/000442 2004-04-01 2005-04-01 Procede de transfert de relais dans un systeme de communication mobile WO2005096641A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CNB2004100309577A CN100353806C (zh) 2004-04-01 2004-04-01 Td－scdma移动通信系统中的接力切换方法
CN200410030957.7 2004-04-01

Publications (1)

Publication Number Publication Date
WO2005096641A1 true WO2005096641A1 (fr) 2005-10-13

Family

ID=35050370

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2005/000442 WO2005096641A1 (fr) 2004-04-01 2005-04-01 Procede de transfert de relais dans un systeme de communication mobile

Country Status (2)

Country Link
CN (1) CN100353806C (zh)
WO (1) WO2005096641A1 (zh)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2011034634A1 (en) * 2009-09-21 2011-03-24 Qualcomm Incorporated Methods and apparatuses for reporting a metric of downlink quality during a baton handover
CN101999243A (zh) * 2009-12-17 2011-03-30 高通股份有限公司 用于td-scdma系统中的接力切换的明确信令的方法和装置
WO2011037649A1 (en) * 2009-09-22 2011-03-31 Qualcomm Incorporated Method and apparatuses for returning the transmission of the uplink to a source cell during a baton handover
WO2011059524A1 (en) * 2009-11-10 2011-05-19 Qualcomm Incorporated Method and apparatus to support hsdpa ack/cqi operation during baton handover in td-scdma systems
WO2011059523A1 (en) * 2009-11-11 2011-05-19 Qualcomm Incorporated Method and apparatus to support hsupa during baton handover in td-scdma systems
CN1996788B (zh) * 2006-12-01 2012-07-04 陕西佳圣通讯科技有限公司 基于卫星同步的td-scdma无线网络直放站时隙配置装置及配置方法
CN101170342B (zh) * 2006-10-23 2012-11-21 华为技术有限公司 无线中继系统及其实现下行数据传输的方法和中继基站
CN104994570A (zh) * 2015-06-30 2015-10-21 上海华为技术有限公司 一种开环功率控制方法和装置

Families Citing this family (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101064943B (zh) * 2006-04-30 2010-05-12 中兴通讯股份有限公司 移动通讯系统基站间上行随机信道或共享信道的切换方法
CN101123792B (zh) * 2006-08-08 2010-12-15 联芯科技有限公司 一种在通信系统中切换的方法及终端装置
CN101132620B (zh) * 2006-08-23 2010-09-08 大唐移动通信设备有限公司 一种信道调整方法
CN101222751B (zh) * 2007-01-12 2012-09-05 华为技术有限公司 一种用户终端、基站及单独下行载波配置信息传输方法及系统
US9295003B2 (en) * 2007-03-19 2016-03-22 Apple Inc. Resource allocation in a communication system
CN101321381B (zh) * 2007-06-04 2012-11-07 华为技术有限公司 一种硬切换方法及系统和移动台
CN101409906B (zh) 2007-10-10 2010-08-18 北京信威通信技术股份有限公司 一种无线通信系统中业务配置的重配方法
US9173148B2 (en) * 2007-10-12 2015-10-27 Qualcomm Incorporated Identification of target node for wireless handoff
WO2010031205A1 (en) * 2008-09-19 2010-03-25 Telefonaktiebolaget L M Ericcson (Publ) Soft handover in a mobile communication network
CN101447812B (zh) * 2008-11-11 2013-02-13 华为技术有限公司 对用户站的发射功率进行调整的方法和装置
CN101909337B (zh) * 2009-06-04 2014-08-13 中兴通讯股份有限公司 基于切换功能的信息传递方法
CN101990779B (zh) * 2009-11-12 2015-04-01 高通股份有限公司 用于在td-scdma切换的过程中在上行链路同步化中校正功率的方法和装置
CN101702817B (zh) * 2009-11-24 2012-09-05 中兴通讯股份有限公司 语音本地交换中的切换方法及装置
WO2011103722A1 (zh) * 2010-02-26 2011-09-01 高通股份有限公司 通信系统中跨小区切换的方法和装置
CN102196488A (zh) * 2010-03-01 2011-09-21 鼎桥通信技术有限公司 一种载波切换方法
US20120163248A1 (en) * 2010-12-23 2012-06-28 Tom Chin Baton Handover From TDD-LTE to TD-SCDMA Systems
CN102223606B (zh) * 2011-07-08 2014-07-02 重庆邮电大学 Td-scdma集群系统组呼中实现接力切换的方法
CN103298049A (zh) * 2012-03-05 2013-09-11 中兴通讯股份有限公司 切换定时器处理方法及装置
CN102665246B (zh) * 2012-04-25 2015-10-28 大唐移动通信设备有限公司 路径切换失败后的资源回收方法和设备
CN104080138B (zh) * 2013-03-29 2017-11-21 中国移动通信集团河北有限公司 小区接力切换方法及装置
CN105992289A (zh) * 2015-03-06 2016-10-05 中兴通讯股份有限公司 一种减少切换时延的方法和装置
CN108632925B (zh) * 2017-03-24 2020-12-08 中国移动通信有限公司研究院 一种基站选择方法及系统
US10477553B2 (en) * 2017-10-31 2019-11-12 Qualcomm Incorporated Aggressive beam selection during handover procedure
CN114900227B (zh) * 2022-07-13 2022-10-04 鹏城实验室 卫星通信系统以及卫星通信链路切换控制方法

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1219091A (zh) * 1998-10-20 1999-06-09 北京信威通信技术有限公司 同步码分多址通信系统接力切换的方法
CN1446009A (zh) * 2002-12-13 2003-10-01 大唐移动通信设备有限公司 一种移动通信系统中的切换方法

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6055428A (en) * 1997-07-21 2000-04-25 Qualcomm Incorporated Method and apparatus for performing soft hand-off in a wireless communication system

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1219091A (zh) * 1998-10-20 1999-06-09 北京信威通信技术有限公司 同步码分多址通信系统接力切换的方法
CN1446009A (zh) * 2002-12-13 2003-10-01 大唐移动通信设备有限公司 一种移动通信系统中的切换方法

Cited By (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101170342B (zh) * 2006-10-23 2012-11-21 华为技术有限公司 无线中继系统及其实现下行数据传输的方法和中继基站
CN1996788B (zh) * 2006-12-01 2012-07-04 陕西佳圣通讯科技有限公司 基于卫星同步的td-scdma无线网络直放站时隙配置装置及配置方法
WO2011034634A1 (en) * 2009-09-21 2011-03-24 Qualcomm Incorporated Methods and apparatuses for reporting a metric of downlink quality during a baton handover
US8830960B2 (en) 2009-09-21 2014-09-09 Qualcomm Incorporated Method and apparatus for maintaining communication during a baton handover
US9094883B2 (en) 2009-09-22 2015-07-28 Qualcomm Incorporated Method and apparatuses for returning the transmission of the uplink to a source cell during a baton handover
WO2011037649A1 (en) * 2009-09-22 2011-03-31 Qualcomm Incorporated Method and apparatuses for returning the transmission of the uplink to a source cell during a baton handover
WO2011059524A1 (en) * 2009-11-10 2011-05-19 Qualcomm Incorporated Method and apparatus to support hsdpa ack/cqi operation during baton handover in td-scdma systems
CN102177744A (zh) * 2009-11-11 2011-09-07 高通股份有限公司 Td-scdma系统中支持接力切换期间的hsupa的方法和装置
WO2011059523A1 (en) * 2009-11-11 2011-05-19 Qualcomm Incorporated Method and apparatus to support hsupa during baton handover in td-scdma systems
WO2011075181A1 (en) * 2009-12-17 2011-06-23 Qualcom Incorporated Method and apparatus for explict signaling of baton handover in td-scdma systems
US8885605B2 (en) 2009-12-17 2014-11-11 Qualcomm Incorporated Method and apparatus for explicit signaling of baton handover in TD-SCDMA systems
CN101999243A (zh) * 2009-12-17 2011-03-30 高通股份有限公司 用于td-scdma系统中的接力切换的明确信令的方法和装置
CN104994570A (zh) * 2015-06-30 2015-10-21 上海华为技术有限公司 一种开环功率控制方法和装置
CN104994570B (zh) * 2015-06-30 2018-11-20 上海华为技术有限公司 一种开环功率控制方法和装置

Also Published As

Publication number Publication date
CN100353806C (zh) 2007-12-05
CN1678115A (zh) 2005-10-05

Similar Documents

Publication Publication Date Title
WO2005096641A1 (fr) Procede de transfert de relais dans un systeme de communication mobile
Tayyab et al. A survey on handover management: From LTE to NR
CN111386728B (zh) 减少移动性中断的方法及其用户设备
AU779979B2 (en) Inter-frequency measurement and handover for wireless communications
US7392052B2 (en) Hard handover method and controller
CN101779386B (zh) 上行链路功率控制参数在切换期间的传送
JP4939529B2 (ja) 専用及び高速共有チャネルのハードハンドオフ手順
US20150181493A1 (en) Handover method and apparatus
US20100311322A1 (en) measure method, a repeater and a base station in the process of cell handoff
WO2006131042A1 (fr) Procédé et équipement utilisateur de transfert cellulaire basé sur système tdd
CN107872851B (zh) 切换方法、系统以及基站
JP4959143B2 (ja) 無線通信ネットワーク、およびモバイル・ユーザ端末との接続のための基地局アンテナを選択する方法
CN111386726A (zh) 无线网络中改进移动稳健性的装置和机制
KR20150119327A (ko) Lte 네트워크에서의 이동 단말 핸드오버
KR20140128456A (ko) 셀룰러 무선 통신 시스템에서의 핸드오버 방법
KR20060030428A (ko) 이동통신망의 하드 핸드오프 제어 방법 및 시스템
TW202019207A (zh) 具有早期準備功能之換手方法及其使用者設備
Saeed Handover in a mobile wireless communication network–A Review Phase
JP2003503922A (ja) 移動体および基地局によってアシストされるネットワークエバリュエイテッドハンドオーバー
CN102892130B (zh) 一种切换参数调整方法
EP4255021A1 (en) Methods and apparatus of ta maintenance and acquisition for mobility with inter-cell beam management
CN114788351A (zh) 辅助小区的替换
WO2003036837A1 (fr) Procédé de transfert en synchronisation en cdma
CN114390616B (zh) 一种mro临界场景的判定方法、装置及设备
WO2011147223A1 (zh) 一种压缩模式的控制方法及系统

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BW BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE EG ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NA NI NO NZ OM PG PH PL PT RO RU SC SD SE SG SK SL SM SY TJ TM TN TR TT TZ UA UG US UZ VC VN YU ZA ZM ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): BW GH GM KE LS MW MZ NA SD SL SZ TZ UG ZM ZW AM AZ BY KG KZ MD RU TJ TM AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LT LU MC NL PL PT RO SE SI SK TR BF BJ CF CG CI CM GA GN GQ GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: DE

WWW Wipo information: withdrawn in national office

Country of ref document: DE

122 Ep: pct application non-entry in european phase