CN103582043A

CN103582043A - Neighborhood selection method and terminal

Info

Publication number: CN103582043A
Application number: CN201210282256.7A
Authority: CN
Inventors: 张亮亮; 柴丽
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2012-08-09
Filing date: 2012-08-09
Publication date: 2014-02-12
Also published as: WO2014023261A1

Abstract

An embodiment of invention discloses a neighborhood selection method and terminal. The method comprises the steps that the terminal obtains a channel state information reference signal (CSI-RS) and a neighborhood proprietary reference signal CRS; the CSI-RS and the CRS are measured, measuring results are obtained, and a target neighborhood of the terminal is selected on the basis of the measuring results. When the method and terminal are used for selecting a neighborhood, the CRS which is reported by a neighbor neighborhood and is used for reflecting control domain signals is measured, and the CRS-RS which is reported by the neighbor neighborhood and is used for reflecting data domain signals is measured, so that the quality of signals which can be received by various neighborhoods can be accurately measured according to the measuring results of the CRS and the CSI-RS, and an accurate target neighborhood can be selected for the terminal.

Description

Cell selection method and terminal

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a cell selection method and a terminal.

Background

A coordinated multi-Point (CoMP) technology is introduced in Long Term Evolution (LTE) to improve a data transmission rate. In a CoMP communication system using CoMP technology, the CoMP communication system includes a plurality of interconnected access points serving a terminal, also called transmission points or nodes or stations of the terminal, where the access points are usually base stations, and the base stations may be macro cell base stations or micro cell base stations, the macro cell base stations are macro base stations, the micro cell base stations are micro base stations, and the forms of the access points include, but are not limited to, pico, femto, and low power stations such as home base stations. Under CoMP, each station transmits a respective Channel State information reference Signal (CSI-RS).

In the prior art, if a connected terminal is switched, a base station needs to select a target cell from a plurality of neighbor cells for the terminal. In the process of selecting a target Cell, a terminal needs to measure Cell Specific Reference signals (CRS) of a plurality of neighbor cells and report the CRS of the plurality of neighbor cells, and a base station selects the target Cell of the terminal according to the measurement result of the CRS. If the idle terminal needs to perform cell selection or cell reselection, the terminal also needs to measure the CRSs of multiple neighbor cells, and selects a suitable cell according to the measurement result of the CRSs.

Particularly, a wide coverage area is provided for each macro base station, in a scenario where the coverage area of a cell corresponding to the macro base station includes a plurality of micro base stations, it is possible that the macro base station provides a control plane service for a terminal, the micro base stations provide a data plane service for the terminal, and a CRS reported by the terminal is mainly used for measuring a control domain signal and cannot well reflect the quality of the data domain signal. Therefore, when the target cell is selected for the terminal according to the measurement result of the CRS, it is difficult to accurately measure the signal quality of the signal that can be received by each neighbor cell, which results in inaccurate target cell selection for the terminal.

Disclosure of Invention

The embodiment of the invention provides a cell selection method and a terminal, aiming at solving the problem that the target cell is not accurately selected for the terminal according to the measurement result of a CRS (cell specific reference signal) in the prior art.

In order to solve the technical problem, the embodiment of the invention discloses the following technical scheme:

in one aspect, a cell selection method is provided, and the method includes:

a terminal acquires channel state information reference signals (CSI-RS) and cell-specific reference signals (CRSs) of at least two neighbor cells;

and measuring the CSI-RS and the CRS to obtain a measurement result, and selecting a target cell of the terminal based on the measurement result.

With reference to the aspect, in a first possible implementation manner, the acquiring, by the terminal, CSI-RSs of at least two neighbor cells includes:

a terminal receives a broadcast message sent by each neighbor cell, wherein the broadcast message comprises CSI-RS information of each neighbor cell;

and receiving the CSI-RS of each neighbor cell according to the CSI-RS information.

With reference to the aspect, in a second possible implementation manner, the acquiring, by the terminal, CSI-RSs of at least two neighbor cells includes:

a terminal receives a Physical Cell Identifier (PCID) of each neighbor cell;

acquiring CSI-RS information of each neighbor cell corresponding to the PCID of each neighbor cell;

With reference to the aspect, in a third possible implementation manner, the acquiring, by the terminal, CSI-RSs of at least two neighbor cells includes:

the terminal receives CSI-RS information of each neighbor cell provided by a service base station of the terminal;

With reference to the first possible implementation manner, the second possible implementation manner, or the third possible implementation manner, in a fourth possible implementation manner, the receiving the CSI-RS of each neighbor cell according to the CSI-RS information includes:

when the CSI-RS information is a CSI-RS resource parameter, receiving the CSI-RS of each neighbor cell according to the CSI-RS resource parameter; or,

and when the CSI-RS information is the index of the CSI-RS resource parameters, acquiring the CSI-RS resource parameters corresponding to the index, and receiving the CSI-RS of each neighbor cell according to the CSI-RS resource parameters.

With reference to the foregoing aspect, in a first possible implementation manner, a second possible implementation manner, a third possible implementation manner, or a fourth possible implementation manner, in a fifth possible implementation manner, the selecting a target cell of the terminal based on the measurement result includes:

when the terminal is in a connection state, reporting the measurement result to a service base station of the terminal so that the service base station selects a switched target cell for the terminal according to the measurement result;

and when the terminal is in an idle state, the terminal performs cell selection or cell reselection according to the measurement result, wherein the cell obtained by the cell selection or cell reselection is the target cell.

With reference to the foregoing aspect, in a sixth possible implementation manner, the selecting a target cell of the terminal based on the measurement result includes:

comparing the CSI-RS measurement values of the at least two neighbor cells, selecting the neighbor cell corresponding to the largest CSI-RS measurement value as a target cell of the terminal, comparing the CRS measurement values of the at least two neighbor cells when the CSI-RS measurement values of the at least two neighbor cells are consistent, and selecting the neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal; or,

comparing the CRS measurement values of the at least two neighbor cells, selecting the neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal, comparing the CSI-RS measurement values of the at least two neighbor cells when the CRS measurement values of the at least two neighbor cells are consistent, and selecting the neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal.

With reference to the foregoing aspect, in a seventh possible implementation manner, the CSI-RS of each neighbor cell includes: the CSI-RS of the primary cell of each neighbor cell, or the CSI-RS of the primary cell of each neighbor cell.

With reference to the seventh possible implementation manner, in an eighth possible implementation manner, the master station includes: a downlink transmission point for sending a control signaling, or a macro base station, or a site corresponding to a macro cell, or a site corresponding to a primary cell, or a site corresponding to a terminal serving cell; the primary cell includes: the method comprises the steps that a cell for sending a control signaling for a terminal, or a cell corresponding to a downlink transmission point for sending the control signaling, or a cell corresponding to a macro base station, or a cell for providing non-access stratum (NAS) mobility information for the terminal in the process of establishing, reestablishing or switching Radio Resource Control (RRC) connection, or a cell for providing safety input for the terminal in the process of establishing or switching the RRC connection.

In another aspect, a terminal is provided, which includes:

the device comprises an acquisition unit, a processing unit and a processing unit, wherein the acquisition unit is used for acquiring channel state information reference signals (CSI-RS) and cell-specific reference signals (CRS) of at least two neighbor cells;

and the measurement unit is used for measuring the CSI-RS and the CRS acquired by the acquisition unit, acquiring a measurement result and selecting the target cell of the terminal based on the measurement result.

With reference to another aspect, in a first possible implementation manner, the obtaining unit includes:

the first information receiving subunit is configured to receive a broadcast message sent by each neighbor cell, where the broadcast message includes CSI-RS information of each neighbor cell;

and the signal receiving subunit is used for receiving the CSI-RS of each neighbor cell according to the CSI-RS information monitored by the first receiving subunit.

With reference to another aspect, in a second possible implementation manner, the obtaining unit includes:

a second identifier receiving subunit, configured to receive a physical cell identifier PCID of each neighbor cell;

a second information obtaining subunit, configured to obtain CSI-RS information of each neighbor cell corresponding to the PCID of each neighbor cell received by the second identifier receiving subunit;

and the signal receiving subunit is used for receiving the CSI-RS of each neighbor cell according to the CSI-RS information acquired by the second information acquisition subunit.

With reference to another aspect, in a third possible implementation manner, the obtaining unit includes:

a third information receiving subunit, configured to receive CSI-RS information of each neighbor cell provided by a serving base station of the terminal;

and the signal receiving subunit is configured to receive the CSI-RS according to the CSI-RS information of each neighbor cell monitored by the third information receiving subunit.

With reference to the foregoing first possible implementation manner, the second possible implementation manner, or the third possible implementation manner, in a fourth possible implementation manner,

the signal receiving subunit is specifically configured to receive, when the CSI-RS information is a CSI-RS resource parameter, a CSI-RS of each neighbor cell according to the CSI-RS resource parameter; or when the CSI-RS information is the index of the CSI-RS resource parameters, acquiring the CSI-RS resource parameters corresponding to the index, and receiving the CSI-RS of each neighbor cell according to the CSI-RS resource parameters.

With reference to the foregoing another aspect, in a fifth possible implementation manner, the terminal further includes at least one of the following units:

a reporting unit, configured to report the measurement result to a serving base station of the terminal when the terminal is in a connected state, so that the serving base station selects a target cell for handover for the terminal according to the measurement result;

and the selecting unit is used for performing cell selection or cell reselection according to the measurement result when the terminal is in an idle state, wherein the cell obtained by the cell selection or cell reselection is the target cell.

With reference to the foregoing another aspect, in a sixth possible implementation manner, the selecting unit includes at least one of the following units:

the first selection subunit is used for comparing the CSI-RS measurement values of the at least two neighbor cells, selecting the neighbor cell corresponding to the largest CSI-RS measurement value as the target cell of the terminal, comparing the CRS measurement values of the at least two neighbor cells when the CSI-RS measurement values of the at least two neighbor cells are consistent, and selecting the neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal;

and the second selecting subunit is used for comparing the CRS measurement values of the at least two neighbor cells, selecting the neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal, comparing the CSI-RS measurement values of the at least two neighbor cells when the CRS measurement values of the at least two neighbor cells are consistent, and selecting the neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal.

In another aspect, a terminal is provided, which includes:

the wireless transceiver is used for acquiring channel state information reference signals CSI-RS and cell-specific reference signals CRS of at least two neighbor cells;

and the processor is used for measuring the CSI-RS and the CRS, obtaining a measurement result and selecting a target cell of the terminal based on the measurement result.

With reference to still another aspect, in a first possible implementation manner, the radio transceiver is specifically configured to receive a broadcast message sent by each neighbor cell, where the broadcast message includes CSI-RS information of each neighbor cell, and receive CSI-RS of each neighbor cell according to the CSI-RS information; or receiving a Physical Cell Identity (PCID) of each neighbor cell, acquiring CSI-RS information of each neighbor cell corresponding to the PCID of each neighbor cell, and receiving the CSI-RS of each neighbor cell according to the CSI-RS information; or receiving CSI-RS information of each neighbor cell provided by a service base station of the terminal, and receiving the CSI-RS of each neighbor cell according to the CSI-RS information.

With reference to the first possible implementation manner, in a second possible implementation manner, the radio transceiver is specifically configured to receive, when the CSI-RS information is a CSI-RS resource parameter, the CSI-RS according to the CSI-RS resource parameter of each neighbor cell; or when the CSI-RS information is the index of the CSI-RS resource parameters, acquiring the CSI-RS resource parameters corresponding to the index, and receiving the CSI-RS of each neighbor cell according to the CSI-RS resource parameters.

With reference to still another aspect, the first possible implementation manner, or the second possible implementation manner, in a third possible implementation manner, the processor is specifically configured to report the measurement result to a serving base station of the terminal when the terminal is in a connected state, so that the serving base station selects a handover target cell for the terminal according to the measurement result, and when the terminal is in an idle state, the terminal performs cell selection or cell reselection according to the measurement result, where a cell obtained by the cell selection or cell reselection is the target cell.

With reference to still another aspect, the first possible implementation manner, the second possible implementation manner, or the third possible implementation manner, in a fourth possible implementation manner, the processor is specifically configured to compare CSI-RS measurement values of the at least two neighbor cells, select a neighbor cell corresponding to a largest CSI-RS measurement value as a target cell of the terminal, compare the CRS measurement values of the at least two neighbor cells when the CSI-RS measurement values of the at least two neighbor cells are consistent, and select a neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal; or comparing the CRS measurement values of the at least two neighbor cells, selecting the neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal, comparing the CSI-RS measurement values of the at least two neighbor cells when the CRS measurement values of the at least two neighbor cells are consistent, and selecting the neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal.

In the embodiment of the invention, the terminal acquires the CSI-RS and the CRS of the neighbor cell, measures the CSI-RS and the CRS to obtain the measurement result, and selects the target cell of the terminal based on the measurement result. By applying the embodiment of the invention, when the cell selection is carried out, besides the CRS which is reported by the neighbor cell and used for reflecting the control domain signal is measured, the CSI-RS which is reported by the neighbor cell and used for reflecting the data domain signal is also measured, thereby accurately measuring the signal quality of the signal which can be received by each neighbor cell according to the measurement results of the CRS and the CSI-RS and selecting an accurate target cell for the terminal.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without inventive exercise.

Fig. 1 is a flowchart of a cell selection method according to an embodiment of the present invention;

fig. 2 is a flowchart of another embodiment of a cell selection method of the present invention;

fig. 3 is a flowchart of another embodiment of a cell selection method of the present invention;

fig. 4 is a flowchart of another embodiment of a cell selection method of the present invention;

FIG. 5 is a block diagram of one embodiment of a terminal of the present invention;

fig. 6 is a block diagram of another embodiment of a terminal of the present invention;

fig. 7 is a block diagram of another embodiment of the terminal of the present invention.

Detailed Description

The following embodiments of the present invention provide a cell selection method and a terminal.

In order to make the technical solutions in the embodiments of the present invention better understood and make the above objects, features and advantages of the embodiments of the present invention more comprehensible, the technical solutions in the embodiments of the present invention are described in further detail below with reference to the accompanying drawings.

The embodiment of the present invention may be applied to various communication networks and systems, where under a network where one base Station (for example, a macro base Station macro enb, the macro base Station is taken as an example below, but the base Station is not limited to the macro base Station) provides coverage, there are multiple small base stations, where the small base stations may be Pico, Relay Station (Relay Station, RS), Remote Radio Head (RRH), or the like, and the small base stations may also be referred to as transmission points (transmission points). These small base stations may be connected to the macro base station by wire, for example, by optical fiber, or by twisted pair, or may be connected to the macro base station by wireless. In the embodiment of the invention, when the cell covered by the macro base station is the neighbor cell, the macro base station can be used as the main site in the neighbor cell.

Referring to fig. 1, a flowchart of a cell selection method according to a first embodiment of the present invention is shown:

step 101: the terminal acquires CSI-RS and CRS of at least two neighbor cells.

The CRS is a cell-specific pilot or may also be referred to as a common pilot, and may be used for channel estimation and demodulation of a control channel or a control domain. The CRS has other uses, and the embodiment will not be described. In the embodiment of the present invention, the CRS of the neighbor cell may include a CRS of a primary station of the neighbor cell, or a CRS of a primary station of the neighbor station, or a CRS of a primary station of the neighbor cell.

The CSI-RS is a reference signal distributed over a data domain and may be used for channel estimation and channel measurement for measuring the data domain. Specifically, the terminal feeds back a Channel Quality Indicator (CQI), a Precoding Matrix Indicator (PMI), a Rank Indicator (RI), a Reference Signal Received Power (RSRP), a Reference Signal Received Quality (RSRQ), and other measurement results to the base station by measuring the CSI-RS, and the base station performs data modulation, scheduling, and the like on the terminal according to the measurement result of the terminal.

In a wireless communication system, for example, in a CoMP scenario, channel estimation demodulation of a control domain or a control channel is performed based on CRS, and measurement of a data domain is performed based on CSI-RS.

In this embodiment, optionally, the CSI-RS of each neighbor cell may be a CSI-RS of each neighbor cell, or a CSI-RS of a primary site of each neighbor cell, or a CSI-RS of a primary cell of a neighbor cell, or the like. In each neighbor cell, the primary site or the primary cell provides a control plane service for the terminal, and other sites outside the primary site or other cells outside the primary cell provide a user plane service for the terminal. The following mainly takes CSI-RS of each neighbor cell or the primary station of each neighbor cell as an example to illustrate the invention.

Wherein, the master site can include: a downlink transmission point for sending the control signaling, or a macro base station, or a station corresponding to a macro cell, or a station corresponding to a primary cell of a first primary cell, or a station corresponding to a serving cell of the terminal.

The primary cell may include: a cell that sends a Control signaling for a terminal, or a cell corresponding to a downlink transmission point that sends the Control signaling, or a cell corresponding to a macro base station, or a cell that provides Non-Access stratum (NAS) mobility information for the terminal during Radio Resource Control (RRC) connection establishment, or re-establishment, or handover, or a cell that provides security input for the terminal during RRC connection establishment or handover.

In this embodiment, when a wide coverage is provided for each macro base station, and a scenario in which a plurality of micro base stations are included in a coverage of a cell corresponding to the macro base station is provided, the macro base station may be particularly used as a master site of the cell.

Optionally, the terminal may receive a broadcast message sent by each neighbor cell, where the broadcast message includes CSI-RS information of each neighbor cell, and receive CSI-RS of each neighbor cell according to the CSI-RS information.

Optionally, the terminal may also receive a Physical Cell Identity (PCID) of each neighbor Cell, acquire CSI-RS information of the primary station of each neighbor Cell corresponding to the PCID of each neighbor Cell, and receive the CSI-RS of each neighbor Cell according to the CSI-RS information.

Optionally, the terminal may also receive CSI-RS information of each neighbor cell provided by a serving base station of the terminal, and receive the CSI-RS of each neighbor cell according to the CSI-RS information.

In this embodiment, the CSI-RS information may be a CSI-RS Resource Parameter (s)), which may also be referred to as CSI-RS Resource configuration information or CSI-RS configuration information. The terminal can accurately receive the CSI-RS signal by using the CSI-RS resource parameters (for example, the CSI-RS signal is received on an antenna port according to the time-frequency resources contained in the CSI-RS resource parameters). A CSI-RS resource parameter may include at least one of the following parameters, it should be noted that the following parameters are only some possible parameters, and the CSI-RS resource parameter in practical application is not limited to the following parameters:

parameter 1: the number of Antenna Ports (Antenna Ports Count) may be { an1, an2, an4, an8}, but the number of Antenna Ports may be identified by other numbers, such as an10, an9, etc., without limitation;

parameter 2: resource configuration (Resource Config), which may include, for example, INTEGER (0..31), etc.;

parameter 3: subframe configuration (Subframe Config), for example, may include inter (0..154), etc.;

parameter 4: scrambling code Initialization Parameter (Scrambling Initialization Parameter), for example, may include inter (0..503), etc.;

parameter 5: CSI-RS Resource Specific Offsets (CSI-RS Resource Specific Offsets).

In this embodiment, the CSI-RS information may also be an index of a CSI-RS resource parameter, for example, the index of the CSI-RS resource parameter may be represented as a CSI-RS index or a CSI-RS ID, where the index is a name provided for a certain CSI-RS resource parameter, so that after the terminal obtains the name, the terminal may obtain a specific CSI-RS resource parameter according to the name. The terminal can obtain the CSI-RS resource parameters corresponding to the indexes of the CSI-RS resource parameters through the mapping relation preserved in advance. For example, the index of one CSI-RS resource parameter is CSI-RS1 (or may also be referred to as CSI-RS index1, or CSI-RS ID1, etc.), which corresponds to the resource parameter of CSI-RS1, the resource parameter of CSI-RS1 may include all 5 parameters listed above, and for example, the index of one CSI-RS resource parameter is CSI-RS2 (or may be referred to as CSI-RS index2, or CSI-RS ID2, etc.), which corresponds to the resource parameter of CSI-RS2, and the resource parameter of CSI-RS2 may include 3 parameters from the 5 parameters listed above.

In the embodiment of the present invention, the manner of acquiring the CRS by the terminal is consistent with that of the prior art, and is not described herein again.

Step 102: and the terminal measures the CSI-RS and the CRS to obtain a measurement result, and selects a target cell of the terminal based on the measurement result.

Optionally, when the terminal is in a connected state, reporting the measurement result to a serving base station of the terminal, so that the serving base station selects a target cell for handover for the terminal according to the measurement result; and when the terminal is in an idle state, the terminal performs cell selection or cell reselection according to the measurement result, wherein the cell obtained by the cell selection or cell reselection is the target cell.

In the above, no matter the base station selects the target cell for the terminal to be handed over, or the terminal performs cell selection or cell reselection, any one of the following manners may be adopted: comparing the CSI-RS measurement values of the at least two neighbor cells, selecting the neighbor cell corresponding to the largest CSI-RS measurement value as a target cell of the terminal, comparing the CRS measurement values of the at least two neighbor cells when the CSI-RS measurement values of the at least two neighbor cells are consistent, and selecting the neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal; or comparing the CRS measurement values of the at least two neighbor cells, selecting the neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal, comparing the CSI-RS measurement values of the at least two neighbor cells when the CRS measurement values of the at least two neighbor cells are consistent, and selecting the neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal.

It should be noted that, in the embodiment of the present invention, the cells obtained by cell selection or cell reselection are collectively referred to as a target cell, so that the unified writing and the description are convenient, but the present invention is not limited to the target cell, for example, the target cell may also be referred to as a cell, a terminal access cell, a terminal serving cell, and the like. In addition, other manners besides the above example may also be adopted for selecting the target cell of the terminal, and the embodiment of the present invention is not limited thereto.

It can be seen from the above embodiments that, when performing cell selection, in addition to measuring the CRS reported by the neighbor cell for reflecting the control domain signal, the CSI-RS reported by the neighbor cell for reflecting the data domain signal is also measured, so that the signal quality of the signal that can be received by each neighbor cell can be accurately measured according to the measurement results of the CRS and the CSI-RS, and an accurate target cell is selected for the terminal.

Referring to fig. 2, a flowchart of another embodiment of the cell selection method of the present invention is shown, where the embodiment shows a process of performing target cell handover by a terminal in a connected state:

step 201: the terminal acquires CRSs of at least two neighbor cells.

In the embodiment of the present invention, the manner of acquiring the CRS by the terminal is consistent with that of the prior art, and is not described herein again. In the embodiment of the present invention, the CRS of the neighbor cell may include a CRS of a primary station of the neighbor cell, or a CRS of a primary station of the neighbor station, or a CRS of a primary station of the neighbor cell.

Step 202: and the terminal receives a broadcast message sent by each neighbor cell, wherein the broadcast message contains CSI-RS information of each neighbor cell.

In this embodiment, optionally, the CSI-RS of each neighbor cell may be a CSI-RS of each neighbor cell, or a CSI-RS of a primary site of each neighbor cell, or a CSI-RS of a primary cell of a neighbor cell, or the like. In each neighbor cell, the primary site or the primary cell provides a control plane service for the terminal, and other sites outside the primary site or other cells outside the primary cell provide a user plane service for the terminal. The following mainly takes CSI-RS of the neighbor cell or the primary station of the neighbor cell as an example to illustrate the contents of the invention.

The primary cell may include: the method comprises the steps that a cell for sending a control signaling for a terminal, or a cell corresponding to a downlink transmission point for sending the control signaling, or a cell corresponding to a macro base station, or a cell for providing NAS mobility information for the terminal in the process of RRC connection establishment, reestablishment or switching, or a cell for providing safety input for the terminal in the process of RRC connection establishment or switching.

In this embodiment, the CSI-RS information may be a CSI-RS Resource Parameter (s)), and the CSI-RS Resource Parameter may also be referred to as CSI-RS Resource configuration information or CSI-RS configuration information, and specific contents of the CSI-RS Resource Parameter may be described in the foregoing step 101, which is not described herein again; the CSI-RS information may also be an index of a CSI-RS resource parameter, for example, the index of the CSI-RS resource parameter may be expressed as a CSI-rsendex, or a CSI-RS ID.

Step 203: and the terminal receives the CSI-RS of each neighbor cell according to the CSI-RS information.

When the CSI-RS information is the CSI-RS resource parameter in step 202, the terminal receives the CSI-RS of each neighbor cell according to the CSI-RS resource parameter.

When the CSI-RS information is an index of the CSI-RS resource parameter in step 202, the terminal may obtain the CSI-RS resource parameter corresponding to the index, and receive the CSI-RS of each neighbor cell according to the CSI-RS resource parameter. The terminal can pre-store the mapping relation between the index of the CSI-RS resource parameter and the CSI-RS resource parameter, and after receiving the index of the CSI-RS resource parameter, the terminal searches the mapping relation to obtain the CSI-RS resource parameter of the neighbor cell which sends the index of the CSI-RS resource parameter.

Step 204: and the terminal measures the CSI-RS and the CRS to obtain a measurement result.

In this embodiment, the method for the terminal to measure the CSI-RS and the CRS is consistent with the prior art, and is not described herein again.

Step 205: and the terminal reports the measurement result to a service base station of the terminal.

Step 206: and the service base station selects a switched target cell for the terminal according to the measurement result.

The serving base station may compare CSI-RS measurement values of the at least two neighbor cells, select a neighbor cell corresponding to a largest CSI-RS measurement value as a target cell of the terminal, compare the CRS measurement values of the at least two neighbor cells when the CSI-RS measurement values of the at least two neighbor cells are consistent, and select a neighbor cell corresponding to a largest CRS measurement value as a target cell of the terminal; or, the serving base station may also compare the CRS measurement values of the at least two neighbor cells, select a neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal, compare the CSI-RS measurement values of the at least two neighbor cells when the CRS measurement values of the at least two neighbor cells are consistent, and select a neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal.

In the embodiment of the present invention, the target cell is selected jointly according to the measurement results of the CRS and the CSI-RS, and the above two possible selection manners are exemplified and are not used to limit the specific manner of selecting the target cell.

In addition, the embodiment of the present invention may also be applied to cell selection in an idle state, where the terminal performs cell selection or reselection according to the measurement results of the CRS and the CSI-RS, and the specific selection process is not limited to the two selection manners described above.

It should be noted that, in this embodiment, the steps of acquiring the CRS and receiving the CSI-RS may not be limited to the order shown in fig. 2, for example, the CSI-RS may be received first and then the CRS is acquired, or the CSI-RS is received while the CRS is acquired, which is not limited in this embodiment.

Referring to fig. 3, a flowchart of another embodiment of the cell selection method of the present invention is shown, where the embodiment shows another process of performing target cell handover for a terminal in a connected state:

step 301: the terminal acquires CRSs of at least two neighbor cells.

Step 302: the terminal receives the PCID of each neighbor cell.

Specifically, each neighbor cell may broadcast a respective PCID so that the terminal obtains the PCID of each neighbor cell.

And 303, the terminal acquires the CSI-RS information of each neighbor cell corresponding to the PCID of each neighbor cell.

The terminal may pre-store a mapping relationship (mapping) between the PCID of each neighbor cell and the CSI-RS information of each neighbor cell, and when receiving the PCID, search for the mapping relationship to obtain the CSI-RS information of the neighbor cell corresponding to the PCID. The following table 1 illustrates the mapping relationship between the PCID and the CSI-RS information:

TABLE 1

In this embodiment, optionally, the CSI-RS of each neighbor cell may be a CSI-RS of each neighbor cell, or a CSI-RS of a primary site of each neighbor cell, or a CSI-RS of a primary cell of each neighbor cell, or the like. In each neighbor cell, the primary site or the primary cell provides a control plane service for the terminal, and other sites outside the primary site or other cells outside the primary cell provide a user plane service for the terminal. The following mainly takes CSI-RS of the neighbor cell or the primary station of the neighbor cell as an example to illustrate the contents of the invention.

Step 304: and the terminal receives the CSI-RS of each neighbor cell according to the CSI-RS information.

And when the CSI-RS information is the CSI-RS resource parameters in the step 303, the terminal receives the CSI-RS of each neighbor cell according to the CSI-RS resource parameters.

When the CSI-RS information is an index of the CSI-RS resource parameter in step 303, the terminal may obtain the CSI-RS resource parameter corresponding to the index, and receive the CSI-RS of each neighbor cell according to the CSI-RS resource parameter. The terminal can pre-store the mapping relation between the index of the CSI-RS resource parameter and the CSI-RS resource parameter, and after receiving the index of the CSI-RS resource parameter, the terminal searches the mapping relation to obtain the CSI-RS resource parameter of the neighbor cell which sends the index of the CSI-RS resource parameter.

Step 305: and the terminal measures the CSI-RS and the CRS to obtain a measurement result.

Step 306: and the terminal reports the measurement result to a service base station of the terminal.

Step 307: and the service base station selects a switched target cell for the terminal according to the measurement result.

Referring to fig. 4, a flow chart of another embodiment of the cell selection method of the present invention is shown, which illustrates a process of cell selection or reselection of a terminal in a connected state:

step 401: the terminal acquires CRSs of at least two neighbor cells.

Step 402: the terminal receives CSI-RS information of each neighbor cell provided by a serving base station of the terminal.

When the terminal is in a connected state, the base station accessed by the terminal is the service base station of the terminal. All base stations in the network can interact CSI-RS information of cells with each other, so that for a service base station of a terminal, the service base station can acquire CSI-RS information of each neighbor cell through interaction, the service base station can send the CSI-RS information of one or more neighbor cells to the terminal, the terminal receives CSI-RS signals of all the neighbor cells through the CSI-RS information, and reports all CSI-RS measurement results to the service base station, so that the service base station can acquire the neighbor cells with better CSI-RS signals according to the measurement results, and therefore the neighbor cells in the neighbor cells are evaluated to be the most suitable switching target cells of the terminal.

Step 403: and the terminal receives the CSI-RS of each neighbor cell according to the CSI-RS information.

And when the CSI-RS information is the CSI-RS resource parameters in the step 402, the terminal receives the CSI-RS of each neighbor cell according to the CSI-RS resource parameters.

When the CSI-RS information is an index of the CSI-RS resource parameter in step 402, the terminal may obtain the CSI-RS resource parameter corresponding to the index, and receive the CSI-RS of each neighbor cell according to the CSI-RS resource parameter. The terminal can pre-store the mapping relation between the index of the CSI-RS resource parameter and the CSI-RS resource parameter, and after receiving the index of the CSI-RS resource parameter, the terminal searches the mapping relation to obtain the CSI-RS resource parameter of the neighbor cell which sends the index of the CSI-RS resource parameter.

Step 404: and the terminal measures the CSI-RS and the CRS to obtain a measurement result.

Step 405: and the terminal reports the measurement result to a service base station of the terminal.

Step 406: and the service base station selects a switched target cell for the terminal according to the measurement result.

The invention also provides an embodiment of the terminal corresponding to the embodiment of the cell selection method.

Referring to fig. 5, a block diagram of an embodiment of the terminal of the present invention is shown:

the terminal includes: an acquisition unit 510 and a measurement unit 520.

The acquiring unit 510 is configured to acquire channel state information reference signals CSI-RS and cell-specific reference signals CRS of at least two neighboring cells;

a measuring unit 520, configured to measure the CSI-RS and the CRS acquired by the acquiring unit 510, obtain a measurement result, and select a target cell of the terminal based on the measurement result.

In one particular embodiment:

the obtaining unit 510 may include (not shown in fig. 5):

In another specific embodiment:

the obtaining unit 510 may include (not shown in fig. 5):

In another specific embodiment:

the obtaining unit 510 may include (not shown in fig. 5):

a third information receiving subunit, configured to receive CSI-RS information of each neighbor cell provided by a serving base station of the terminal; the CSI-RS information of each neighbor cell is obtained by interaction between the service base station and the base station corresponding to each neighbor cell;

Optionally, in the above embodiment, the signal receiving subunit may be specifically configured to receive, when the CSI-RS information is a CSI-RS resource parameter, a CSI-RS of each neighbor cell according to the CSI-RS resource parameter; or when the CSI-RS information is the index of the CSI-RS resource parameters, acquiring the CSI-RS resource parameters corresponding to the index, and receiving the CSI-RS of each neighbor cell according to the CSI-RS resource parameters.

Referring to fig. 6, a block diagram of another embodiment of the terminal of the present invention is shown:

the terminal includes: an obtaining unit 610, a measuring unit 620, a reporting unit 630 and a selecting unit 640.

The acquiring unit 610 is configured to acquire channel state information reference signals CSI-RS and cell-specific reference signals CRS of at least two neighboring cells;

a measuring unit 620, configured to measure the CSI-RS and the CRS acquired by the acquiring unit 510, obtain a measurement result, and select a target cell of the terminal based on the measurement result;

a reporting unit 630, configured to report the measurement result to a serving base station of the terminal when the terminal is in a connected state, so that the serving base station selects a target cell for handover for the terminal according to the measurement result;

a selecting unit 640, configured to perform cell selection or cell reselection according to the measurement result when the terminal is in an idle state, where a cell obtained by the cell selection or cell reselection is the target cell.

In one particular embodiment:

the acquisition unit 610 may include (not shown in fig. 6):

In another specific embodiment:

the acquisition unit 610 may include (not shown in fig. 6):

In another specific embodiment:

the acquisition unit 610 may include (not shown in fig. 6):

In the above embodiment, optionally, the selecting unit 640 may include at least one of the following units (not shown in fig. 6):

Referring to fig. 7, a block diagram of another embodiment of the terminal of the present invention is shown, where the terminal may specifically be a mobile phone, although the form of the terminal is not limited to this, and the terminal may also be a data card or any other form of wireless terminal:

the terminal includes: a radio Transceiver (Transceiver) 710 and a Processor (Processor) 720.

A wireless transceiver 710, configured to acquire channel state information reference signals CSI-RS and cell-specific reference signals CRS of at least two neighboring cells;

and a processor 720, configured to measure the CSI-RS and the CRS, obtain a measurement result, and select a target cell of the terminal based on the measurement result.

Optionally, the radio transceiver may be specifically configured to receive a broadcast message sent by each neighbor cell, where the broadcast message includes CSI-RS information of each neighbor cell, and receive CSI-RS of each neighbor cell according to the CSI-RS information; or receiving a Physical Cell Identity (PCID) of each neighbor cell, acquiring CSI-RS information of each neighbor cell corresponding to the PCID of each neighbor cell, and receiving the CSI-RS of each neighbor cell according to the CSI-RS information; or receiving CSI-RS information of each neighbor cell provided by a service base station of the terminal, and receiving the CSI-RS of each neighbor cell according to the CSI-RS information.

Optionally, the radio transceiver may be specifically configured to receive, when the CSI-RS information is a CSI-RS resource parameter, the CSI-RS according to the resource parameter of the CSI-RS of each neighbor cell; or when the CSI-RS information is the index of the CSI-RS resource parameters, acquiring the CSI-RS resource parameters corresponding to the index, and receiving the CSI-RS of each neighbor cell according to the CSI-RS resource parameters.

Optionally, the processor may be specifically configured to, when the terminal is in a connected state, report the measurement result to a serving base station of the terminal, so that the serving base station selects a target cell to be switched for the terminal according to the measurement result, when the terminal is in an idle state, the terminal performs cell selection or cell reselection according to the measurement result, and a cell obtained by the cell selection or cell reselection is the target cell.

Optionally, the processor may be specifically configured to compare CSI-RS measurement values of the at least two neighbor cells, select a neighbor cell corresponding to a largest CSI-RS measurement value as a target cell of the terminal, compare CRS measurement values of the at least two neighbor cells when the CSI-RS measurement values of the at least two neighbor cells are consistent, and select a neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal; or comparing the CRS measurement values of the at least two neighbor cells, selecting the neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal, comparing the CSI-RS measurement values of the at least two neighbor cells when the CRS measurement values of the at least two neighbor cells are consistent, and selecting the neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal.

The embodiments of the present invention may be applied to a CoMP communication system, where the communication system includes a plurality of access points or transmission points connected to each other, such as base stations, where the base stations may be Macro base stations (Macro enbs, or enbs), or micro base stations (Pico base stations, Relay, HeNB, HNB, RRH), and the like, and the embodiments are not limited herein, and in short, a station or a transmission point.

In the embodiment of the present invention, a macro base station corresponding to a macro cell is illustrated as an eNB, and a micro base station corresponding to a micro cell is illustrated as an RRH. In general, a wireless communication system may be divided into a homogeneous network communication system and a heterogeneous network communication system, where base stations interconnected in the homogeneous network communication system are macro cell base stations, and base stations interconnected in the heterogeneous network communication system may be macro cell base stations and micro cell base stations. All base stations in the CoMP communication system provide services for a terminal, which is generally referred to as a UE (User Equipment), and may also be called a User terminal or a terminal.

It can be seen from the above embodiments that the terminal acquires the CSI-RS and the CRS of the neighbor cell, measures the CSI-RS and the CRS, obtains a measurement result, and selects the target cell of the terminal based on the measurement result. By applying the embodiment of the invention, when the cell selection is carried out, besides the CRS which is reported by the neighbor cell and used for reflecting the control domain signal is measured, the CSI-RS which is reported by the neighbor cell and used for reflecting the data domain signal is also measured, thereby accurately measuring the signal quality of the signal which can be received by each neighbor cell according to the measurement results of the CRS and the CSI-RS and selecting an accurate target cell for the terminal.

Those skilled in the art will readily appreciate that the techniques of the embodiments of the present invention may be implemented as software plus a required general purpose hardware platform. Based on such understanding, the technical solutions in the embodiments of the present invention may be essentially or partially implemented in the form of a software product, which may be stored in a storage medium, such as ROM/RAM, magnetic disk, optical disk, etc., and includes several instructions for enabling a computer device (which may be a personal computer, a server, or a network device, etc.) to execute the method according to the embodiments or some parts of the embodiments.

The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for the system embodiment, since it is substantially similar to the method embodiment, the description is simple, and for the relevant points, reference may be made to the partial description of the method embodiment.

The above-described embodiments of the present invention do not limit the scope of the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method of cell selection, the method comprising:

2. The method of claim 1, wherein the acquiring the CSI-RSs of at least two neighbor cells by the terminal comprises:

3. The method of claim 1, wherein the acquiring the CSI-RSs of at least two neighbor cells by the terminal comprises:

a terminal receives a Physical Cell Identifier (PCID) of each neighbor cell;

4. The method of claim 1, wherein the acquiring the CSI-RSs of at least two neighbor cells by the terminal comprises:

5. The method of claim 4, wherein the CSI-RS information of each neighbor cell is CSI-RS information obtained by interaction between the serving base station and the base station corresponding to each neighbor cell.

6. The method according to any one of claims 2 to 5, wherein the receiving the CSI-RS of each neighbor cell according to the CSI-RS information comprises:

7. The method according to any of claims 1 to 6, wherein the selecting the target cell of the terminal based on the measurement result comprises:

8. The method according to any of claims 1 to 7, wherein the selecting the target cell of the terminal based on the measurement result comprises:

9. The method according to any of claims 1 to 8, wherein the CSI-RS of each neighbor cell comprises: the CSI-RS of the primary cell of each neighbor cell, or the CSI-RS of the primary cell of each neighbor cell.

10. The method of claim 9,

the master site includes: a downlink transmission point for sending a control signaling, or a macro base station, or a site corresponding to a macro cell, or a site corresponding to a primary cell of a first primary cell, or a site corresponding to a serving cell of a terminal;

the primary cell includes: the method comprises the steps that a cell for sending a control signaling for a terminal, or a cell corresponding to a downlink transmission point for sending the control signaling, or a cell corresponding to a macro base station, or a cell for providing non-access stratum (NAS) mobility information for the terminal in the process of establishing, reestablishing or switching Radio Resource Control (RRC) connection, or a cell for providing safety input for the terminal in the process of establishing or switching the RRC connection.

11. The method according to claim 9 or 10, wherein in each neighbor cell, the primary site or the primary cell provides control plane service for the terminal, and other sites outside the primary site or other cells outside the primary cell provide user plane service for the terminal.

12. A terminal, characterized in that the terminal comprises:

13. The terminal of claim 12, wherein the obtaining unit comprises:

14. The terminal of claim 12, wherein the obtaining unit comprises:

15. The terminal of claim 12, wherein the obtaining unit comprises:

16. The terminal of claim 15, wherein the CSI-RS information of each neighbor cell is CSI-RS information obtained by the serving base station interacting with the base station corresponding to each neighbor cell.

17. The terminal according to any of claims 13 to 16,

18. The terminal according to any of claims 12 to 17, characterized in that the terminal further comprises at least one of the following units:

19. The terminal according to claim 18, wherein the selection unit comprises at least one of the following units:

20. A terminal, characterized in that the terminal comprises:

21. The terminal of claim 20,

the wireless transceiver is specifically configured to receive a broadcast message sent by each neighbor cell, where the broadcast message includes CSI-RS information of each neighbor cell, and receive CSI-RS of each neighbor cell according to the CSI-RS information; or receiving a Physical Cell Identity (PCID) of each neighbor cell, acquiring CSI-RS information of each neighbor cell corresponding to the PCID of each neighbor cell, and receiving the CSI-RS of each neighbor cell according to the CSI-RS information; or receiving CSI-RS information of each neighbor cell provided by a service base station of the terminal, and receiving the CSI-RS of each neighbor cell according to the CSI-RS information.

22. The terminal of claim 21,

the wireless transceiver is specifically configured to receive the CSI-RS according to the resource parameters of the CSI-RS of each neighbor cell when the CSI-RS information is CSI-RS resource parameters; or when the CSI-RS information is the index of the CSI-RS resource parameters, acquiring the CSI-RS resource parameters corresponding to the index, and receiving the CSI-RS of each neighbor cell according to the CSI-RS resource parameters.

23. The terminal according to any of the claims 20 to 22,

the processor is specifically configured to report the measurement result to a serving base station of the terminal when the terminal is in a connected state, so that the serving base station selects a target cell to be switched for the terminal according to the measurement result, and when the terminal is in an idle state, the terminal performs cell selection or cell reselection according to the measurement result, where a cell obtained by the cell selection or cell reselection is the target cell.

24. The terminal according to any of the claims 20 to 23,

the processor is specifically configured to compare CSI-RS measurement values of the at least two neighbor cells, select a neighbor cell corresponding to a largest CSI-RS measurement value as a target cell of the terminal, compare CRS measurement values of the at least two neighbor cells when the CSI-RS measurement values of the at least two neighbor cells are consistent, and select a neighbor cell corresponding to a largest CRS measurement value as a target cell of the terminal; or comparing the CRS measurement values of the at least two neighbor cells, selecting the neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal, comparing the CSI-RS measurement values of the at least two neighbor cells when the CRS measurement values of the at least two neighbor cells are consistent, and selecting the neighbor cell corresponding to the largest CRS measurement value as the target cell of the terminal.