CN107889066B

CN107889066B - Cell reselection method, base station and terminal

Info

Publication number: CN107889066B
Application number: CN201610875291.8A
Authority: CN
Inventors: 张元�; 梁靖; 傅婧
Original assignee: China Academy of Telecommunications Technology CATT
Current assignee: China Academy of Telecommunications Technology CATT; Datang Mobile Communications Equipment Co Ltd
Priority date: 2016-09-30
Filing date: 2016-09-30
Publication date: 2020-04-17
Anticipated expiration: 2036-09-30
Also published as: CN107889066A

Abstract

The invention provides a cell reselection method, a base station and a terminal, which relate to the field of communication and are applied to a cell reselection method at a base station side, and the cell reselection method comprises the following steps: determining a cell reselection type currently supported by a network; and sending the cell reselection reference factor to a terminal according to the cell reselection type, so that the terminal reselects the cell according to the cell reselection reference factor. The cell reselection method applied to the terminal side comprises the following steps: receiving a cell reselection reference factor sent by a base station; acquiring a preset rule for a terminal to reselect a cell; and determining the reselected cell according to the preset rule and the cell reselection reference factor. The invention improves the efficiency of receiving the multicast service after the terminal cell is reselected and simultaneously reduces the power consumption of the terminal for receiving the multicast service by providing the cell reselection mode of the terminal supporting the multicast service under multiple carriers.

Description

Cell reselection method, base station and terminal

Technical Field

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

Background

The narrowband Internet of Things (NB-IoT) working phase (Work Item, WI) passes and starts in the 3GPP Release 13(Release 13, R13) phase. The narrow-band Internet of Things is aimed at standardizing the wireless access of the Cellular Internet of Things (CIoT), the technology is expanded based on Long Term Evolution (LTE)/long term evolution subsequent evolution (LTE-a), and the network characteristics/targets mainly considered are as follows: the indoor coverage is enhanced, the access of a large number of low-speed devices is supported, the delay sensitivity is low, the device cost is reduced, the device power consumption is reduced, the network architecture is optimized, and the like.

An actual NB-IoT terminal may have characteristics of low mobility, low real-time requirement for data transmission with the network side, extremely low power consumption requirement, information transmission with a small data amount with the network side, and low implementation complexity.

To reduce cell load, NB-IoT supports multiple carrier operation, where carriers are divided into primary and secondary carriers. The terminal on the primary carrier can receive Narrowband Physical Broadcast Channel (NPBCH)/Narrowband Primary Synchronization Signal (NPSS), Narrowband Secondary Synchronization Signal (NSSS) and in-band Signaling (SIB) transmission, and the R13 terminal on the secondary carrier currently only expects narrowband physical downlink control channel (NB-PDCCH)/narrowband physical downlink shared channel (NB-PDSCH) and/or narrowband physical uplink shared channel (NB-PUSCH), and therefore the NB-IoT terminal cannot simultaneously operate on multiple carriers due to limited capability. In R13, the terminal performs cell reselection only by referring to a Reference Signal Received Power (RSRP) value of a main carrier of a target cell or a Reference Signal Received Quality (RSRQ) value of a Reference Signal, and in R14, downlink transmission power of the main carrier and the secondary carrier may be adjusted according to needs of an operator.

After a terminal supporting the multicast service by NB-IoT reselects a cell by measuring RSRP of a primary carrier, it needs to receive the multicast service on a carrier supporting the multicast service, and when the carrier supporting the multicast service is a non-primary carrier and downlink transmission power of the carrier is lower than that of the primary carrier, it may cause a long delay and increased power consumption for the terminal to receive the multicast service. After a terminal supporting the multicast service by NB-IoT reselects a cell by measuring RSRQ of a primary carrier, it needs to receive the multicast service on a carrier supporting the multicast service, and when the carrier supporting the multicast service is a non-primary carrier and RSRQ of the carrier is lower than RSRQ of the primary carrier, a delay of the terminal receiving the multicast service may be lengthened and power consumption may be increased. It can be seen from this that efficient cell reselection cannot be achieved when a terminal supports a multicast service.

Disclosure of Invention

The technical problem to be solved by the present invention is to provide a cell reselection method, a base station and a terminal, so as to solve the problem that efficient cell reselection cannot be implemented when the existing terminal supports a multicast service.

In order to solve the foregoing technical problem, an embodiment of the present invention provides a cell reselection method, including:

determining a cell reselection type currently supported by a network;

and sending the cell reselection reference factor to a terminal according to the cell reselection type, so that the terminal reselects the cell according to the cell reselection reference factor.

Further, the step of sending the cell reselection reference factor to the terminal includes:

transmitting a cell reselection reference factor to a terminal on a single-cell multicast control channel, wherein the cell reselection reference factor comprises single-cell multicast service channel configuration information of a serving cell of the terminal and information of a neighbor cell of the terminal supporting a multicast service of the serving cell, and the information of the neighbor cell comprises: the cell identification information and the main carrier frequency information of the cell, wherein the single-cell multicast service channel configuration information of the serving cell includes: the method comprises the steps that multicast session information of a serving cell, a transmission identifier corresponding to a single-cell multicast service channel of the serving cell, scheduling information of the single-cell multicast service channel of the serving cell, indication information of whether an adjacent cell supports a multicast service supported by the serving cell or not and preset information of a multicast service carrier wave sent by the adjacent cell are obtained; or

Transmitting a cell reselection reference factor to a terminal on a single-cell multicast control channel, wherein the cell reselection reference factor comprises: multicast session information of all multicast services supported by a terminal neighbor cell and preset information of multicast service carriers sent by the neighbor cell; or

Transmitting a cell reselection reference factor to a terminal through a first system broadcast message, wherein the cell reselection reference factor comprises: the method comprises the steps that multicast session information of all multicast services supported by a neighbor cell of a terminal and preset information of multicast service carriers sent by the neighbor cell.

Further, when the cell reselection type is cell reselection based on reference signal received power, the preset information is a difference value between transmission power of a multicast service carrier sent by an adjacent cell and transmission power of a main carrier of the adjacent cell;

and when the cell reselection type is cell reselection based on the reference signal receiving quality, the preset information is the frequency of the multicast service carrier sent by the adjacent cell.

Further, the cell reselection method further includes:

and sending the adjusting parameters corresponding to the cell reselection type to the terminal through a second system broadcast message according to the cell reselection type.

Further, when the cell reselection type is cell reselection based on reference signal received power, the adjustment parameter corresponding to the cell reselection type includes calculating a corresponding relationship between an offset value of the reference signal received power and/or a difference value between the offset value and transmission power of a multicast service carrier sent by an adjacent cell and transmission power of a main carrier of the multicast service carrier;

and when the cell reselection type is cell reselection based on the reference signal receiving quality, the adjustment parameters corresponding to the cell reselection type comprise an adjustment quantity for calculating the reference signal receiving quality and/or a corresponding relation between the adjustment quantity and the reference signal receiving quality and a first preset number of adjacent cells preferred by the terminal.

An embodiment of the present invention provides a base station, including:

a first determining module, configured to determine a cell reselection type currently supported by a network;

and the first sending module is used for sending the cell reselection reference factor to the terminal according to the cell reselection type, so that the terminal reselects the cell according to the cell reselection reference factor.

Further, the first sending module is configured to:

Further, the base station further includes:

and the second sending module is used for sending the adjusting parameters corresponding to the cell reselection types to the terminal through a second system broadcast message according to the cell reselection types.

The embodiment of the invention provides a cell reselection method, which comprises the following steps:

receiving a cell reselection reference factor sent by a base station;

acquiring a preset rule for a terminal to reselect a cell;

and determining the reselected cell according to the preset rule and the cell reselection reference factor.

Further, when the cell reselection reference factor includes a difference between the transmission power of a multicast service carrier sent by an adjacent cell and the transmission power of a main carrier of the adjacent cell, and the preset rule is a cell supporting a preset service of a terminal, the step of determining the reselected cell according to the preset rule and the cell reselection reference factor includes:

determining a first cell supporting a preset service of a terminal;

measuring the reference signal receiving power of a carrier supporting the multicast service of each cell in the first cell;

judging whether a second cell which supports the reference signal receiving power of the carrier wave of the multicast service and meets the S criterion exists in the first cell;

if the second cell exists, adding a difference value corresponding to the reference signal receiving power of the carrier supporting the multicast service of each cell in the second cell to obtain a first reference signal receiving power, and taking the cell with the maximum first reference signal receiving power in the second cell as a reselected cell;

and if the second cell does not exist, measuring the reference signal receiving power of the main carrier waves of all the adjacent cells of the terminal, and taking the cell with the maximum reference signal receiving power of the main carrier waves in all the adjacent cells as the reselected cell.

Further, when the cell reselection reference factor includes a difference between the transmission power of a multicast service carrier sent by an adjacent cell and the transmission power of a main carrier of the adjacent cell, and the preset rule is a priority of all the adjacent cells and a cell considering a preset multicast service for a terminal, the step of determining the reselected cell according to the preset rule and the cell reselection reference factor includes:

acquiring an adjustment parameter corresponding to a cell reselection type sent by a base station, wherein the adjustment parameter corresponding to the cell reselection type comprises a corresponding relation of a bias value of a reference signal receiving power and/or a difference value between the bias value and a transmission power of a multicast service carrier sent by an adjacent cell and a transmission power of a main carrier of the multicast service carrier;

determining a third cell supporting a preset service of the terminal;

measuring the reference signal received power of the carrier supporting the multicast service of each cell in the third cell;

judging whether a fourth cell which supports the reference signal receiving power of the carrier wave of the multicast service and meets the S criterion exists in the third cell;

adding the reference signal received power of the carrier supporting the multicast service of each cell in the fourth cell to a bias value corresponding to the reference signal received power to obtain second reference signal received power;

and selecting the cell with the maximum reference signal receiving power of the second reference signal receiving power in all the fourth cells, the reference signal receiving power of the carrier supporting the multicast service which does not belong to the fourth cells in the third cells and the reference signal receiving power of the main carrier in the cell not supporting the preset service of the terminal as the reselected cell.

Further, when the cell reselection reference factor includes a frequency of a multicast service carrier sent by an adjacent cell and the preset rule is a cell supporting a preset service of a terminal, the step of determining the reselected cell according to the preset rule and the cell reselection reference factor includes:

determining a fifth cell supporting a preset service of the terminal;

measuring the reference signal receiving quality of a carrier supporting the multicast service of each cell in the fifth cell;

judging whether a sixth cell with reference signal receiving quality of a carrier supporting the multicast service meeting S criteria exists in the fifth cell;

if the sixth cell exists, taking the cell with the maximum reference signal receiving quality of the carrier supporting the multicast service in the sixth cell as the reselected cell;

and if the sixth cell does not exist, measuring the reference signal receiving quality of the main carrier waves of all the adjacent cells of the terminal, and taking the cell with the maximum reference signal receiving quality in all the adjacent cells as the reselected cell.

Further, when the cell reselection reference factor includes a frequency of a multicast service carrier sent by an adjacent cell, and the preset rule is priorities of all adjacent cells and a cell considering supporting a terminal preset multicast service, the step of determining the reselected cell according to the preset rule and the cell reselection reference factor includes:

acquiring adjustment parameters corresponding to a cell reselection type sent by a base station, wherein the adjustment parameters corresponding to the cell reselection type comprise adjustment quantity for calculating reference signal receiving quality and/or a corresponding relation between the adjustment quantity and the reference signal receiving quality and a first preset number of adjacent cells preferred by a terminal;

measuring the reference signal receiving quality of main carriers of all adjacent cells of a terminal;

determining a first preset number of seventh cells meeting S criteria according to the reference signal receiving quality of the main carriers of all the adjacent cells;

measuring the reference signal receiving quality of a carrier wave of a preset multicast service of each cell sending terminal in the seventh cell;

judging whether an eighth cell of which the reference signal receiving quality of the carrier supporting the multicast service meets the S criterion exists in the seventh cell;

when the eighth cell exists, adding the adjustment quantity to the reference signal receiving quality of the carrier supporting the multicast service of the eighth cell to obtain first reference signal receiving quality;

and taking the largest cell in the first reference signal receiving quality in the eighth cell and the reference signal receiving quality of the carrier supporting the multicast service, which does not belong to the eighth cell, in the seventh cell as the cell after the terminal is reselected.

An embodiment of the present invention provides a terminal, including:

the receiving module is used for receiving the cell reselection reference factor sent by the base station;

the acquisition module is used for acquiring a preset rule for the terminal to reselect the cell;

and the second determining module is used for determining the reselected cell according to the preset rule and the cell reselection reference factor.

Further, when the cell reselection reference factor includes a difference between the transmission power of the multicast service carrier sent by the neighboring cell and the transmission power of the primary carrier, and the preset rule is a cell supporting a preset service of the terminal, the second determining module includes:

a first determining unit, configured to determine a first cell supporting a preset service of a terminal;

a first measurement unit, configured to measure a reference signal received power of a carrier supporting a multicast service in each cell of the first cells;

a first judging unit, configured to judge whether a second cell, in which reference signal received power of a carrier supporting a multicast service meets an S criterion, exists in the first cell;

a second determining unit, configured to add, if there is the second cell, the reference signal received power of a carrier supporting the multicast service of each cell in the second cells to a difference corresponding to the reference signal received power to obtain a first reference signal received power, and use a cell with a maximum first reference signal received power in the second cells as a reselected cell;

and a third determining unit, configured to measure the reference signal received power of the primary carriers of all the neighboring cells of the terminal if the second cell does not exist, and use a cell with the largest reference signal received power of the primary carriers in all the neighboring cells as the reselected cell.

Further, when the cell reselection reference factor includes a difference between the transmission power of the multicast service carrier sent by the neighboring cell and the transmission power of the main carrier thereof, and the preset rule is a priority of all neighboring cells and a cell considering that the terminal supports a preset multicast service, the second determining module includes:

a first obtaining unit, configured to obtain an adjustment parameter corresponding to a cell reselection type sent by a base station, where the adjustment parameter corresponding to the cell reselection type includes a corresponding relationship between a bias value of a calculated reference signal received power and/or a difference between the bias value and a difference between a transmission power of a multicast service carrier sent by an adjacent cell and a transmission power of a main carrier of the multicast service carrier;

a fourth determining unit, configured to determine a third cell supporting a preset service of the terminal;

a second measuring unit, configured to measure a reference signal received power of a carrier supporting a multicast service in each cell in the third cell;

a second determining unit, configured to determine whether a fourth cell in which reference signal received power of a carrier supporting a multicast service meets an S criterion exists in the third cell;

a first calculating unit, configured to add the reference signal received power of the carrier supporting the multicast service of each cell in the fourth cell to a corresponding offset value to obtain a second reference signal received power;

and the first selecting unit is used for selecting the cell with the maximum reference signal receiving power of the second reference signal receiving power in all the fourth cells, the reference signal receiving power of the carrier supporting the multicast service, which does not belong to the fourth cell, in the third cell and the reference signal receiving power of the main carrier in the cell not supporting the terminal preset service as the reselected cell.

Further, when the cell reselection reference factor includes a frequency of a multicast service carrier sent by an adjacent cell and the preset rule is a cell supporting a preset service of a terminal, the second determining module includes:

a fifth determining unit, configured to determine a fifth cell supporting a preset service of the terminal;

a third measuring unit, configured to measure a reference signal reception quality of a carrier supporting a multicast service in each cell of the fifth cells;

a third determining unit, configured to determine whether a sixth cell exists in the fifth cell, where reference signal reception quality of a carrier supporting a multicast service meets an S criterion;

a sixth determining unit, configured to, if the sixth cell exists, take a cell with a largest reference signal reception quality of a carrier supporting a multicast service in the sixth cell as a reselected cell;

a seventh determining unit, configured to measure, if the sixth cell does not exist, reference signal reception quality of the primary carriers of all neighboring cells of the terminal, and use a cell with the largest reference signal reception quality among all neighboring cells as a reselected cell.

Further, when the cell reselection reference factor includes a frequency of a multicast service carrier sent by a neighboring cell, and the preset rule is priorities of all neighboring cells and a cell considering supporting a terminal to preset a multicast service, the second determining module includes:

a second obtaining unit, configured to obtain an adjustment parameter corresponding to a cell reselection type sent by a base station, where the adjustment parameter corresponding to the cell reselection type includes an adjustment amount for calculating reference signal received quality and/or a correspondence between the adjustment amount and the reference signal received quality, and a first preset number of neighboring cells preferred by a terminal;

a fourth measuring unit, configured to measure reference signal reception quality of the primary carriers of all neighboring cells of the terminal;

an eighth determining unit, configured to determine, according to the reference signal reception quality of the primary carriers of all the neighboring cells, a first preset number of seventh cells that meet an S criterion;

a fifth measuring unit, configured to measure a reference signal reception quality of a carrier where a multicast service is preset by a sending terminal of each cell in the seventh cell;

a fourth determining unit, configured to determine whether an eighth cell whose reference signal reception quality of a carrier supporting a multicast service meets an S criterion exists in the seventh cell;

a ninth determining unit, configured to add the adjustment amount to the reference signal reception quality of the carrier supporting the multicast service in the eighth cell to obtain a first reference signal reception quality when the eighth cell exists;

a tenth determining unit, configured to use the largest cell of the first reference signal reception quality in the eighth cell and the reference signal reception quality of the carrier supporting the multicast service, which does not belong to the eighth cell, in the seventh cell as the cell after the terminal is reselected.

The invention has the beneficial effects that:

according to the scheme, the base station issues the cell reselection reference factor to the terminal, and the terminal reselects the cell according to the preset rule of cell reselection and the cell reselection reference factor.

Drawings

Fig. 1 is a flowchart illustrating a cell reselection method according to a first embodiment of the present invention;

fig. 2 is a block diagram of a base station according to a second embodiment of the present invention;

fig. 3 is a schematic structural diagram of a base station according to a third embodiment of the present invention;

fig. 4 is a flowchart illustrating a cell reselection method according to a fourth embodiment of the present invention;

fig. 5 is a block diagram of a terminal according to a fifth embodiment of the present invention;

fig. 6 is a schematic structural diagram of a terminal according to a sixth embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in detail with reference to the accompanying drawings and specific embodiments.

The invention provides a cell reselection method, a base station and a terminal, aiming at the problem that the existing terminal can not realize efficient cell reselection under the condition that the terminal supports multicast services.

Example one

As shown in fig. 1, an embodiment of the present invention provides a cell reselection method, applied to a base station side, including:

step 11, determining a cell reselection type currently supported by a network;

it should be noted that two cell reselection types are provided in the embodiment of the present invention, one is to perform cell reselection based on reference signal received power (RSRQ), and the other is to perform cell reselection based on reference signal received quality (RSRP), and at the same time, the base station can only select one cell reselection type.

And step 12, sending the cell reselection reference factor to a terminal according to the cell reselection type, so that the terminal reselects the cell according to the cell reselection reference factor.

It should be noted that, after the cell reselection type is determined, the cell reselection reference factor sent by the base station is also determined, and specifically, the implementation of step 12 includes:

step 121, transmitting a cell reselection reference factor to a terminal on a single cell multicast control channel (SC-MCCH), wherein the cell reselection reference factor comprises single cell multicast traffic channel (SC-MTCH) configuration information of a serving cell of the terminal and information of neighbor cells of the terminal supporting a multicast service of the serving cell, and the information of the neighbor cells comprises: the cell identification information and the main carrier frequency information of the cell, wherein the single-cell multicast service channel configuration information of the serving cell includes: the method comprises the steps that multicast session information of a serving cell, a transmission identifier (G-RNTI) corresponding to a single-cell multicast service channel of the serving cell, scheduling information of the single-cell multicast service channel of the serving cell, indication information of whether an adjacent cell supports multicast services supported by the serving cell or not and preset information of multicast service carriers sent by the adjacent cell; or

Step 122, sending a cell reselection reference factor to the terminal on the single-cell multicast control channel, wherein the cell reselection reference factor includes: multicast session information of all multicast services supported by a terminal neighbor cell and preset information of multicast service carriers sent by the neighbor cell; or

Step 123, sending a cell reselection reference factor to the terminal through a first system broadcast message, wherein the cell reselection reference factor includes: the method comprises the steps that multicast session information of all multicast services supported by a neighbor cell of a terminal and preset information of multicast service carriers sent by the neighbor cell.

Specifically, the cell reselection type in the embodiment of the present invention mainly determines specific content of the preset information, that is, when the cell reselection type is cell reselection based on reference signal received power, the preset information is a difference between transmission power of a multicast service carrier sent by an adjacent cell and transmission power of a main carrier of the adjacent cell; it should be noted here that, when there is no difference between the transmission power of the multicast service carrier sent by the neighboring cell and the transmission power of the main carrier, it indicates that the multicast service carrier is the main carrier, and in this case, the base station may select not to send the difference of the neighboring cell.

When the cell reselection type is cell reselection based on the reference signal reception quality, the preset information is the frequency at which the neighboring cell transmits the multicast service carrier, and it should be noted that, when the neighboring cell transmits the multicast service on the primary carrier, the base station may select the frequency at which the multicast service carrier is not transmitted.

It should be further noted that, when the terminal performs cell reselection, the terminal performs reselection according to a preset rule of cell reselection, and when the preset rule of cell reselection includes a priority of a cell that supports a preset multicast service of the terminal, the base station further needs to send an adjustment parameter corresponding to a cell reselection type to the terminal through a second system broadcast message.

It should be noted that the specific content of the adjustment parameter corresponding to the cell reselection type is also determined according to the cell reselection type, and when the cell reselection type is cell reselection based on the reference signal received power, the adjustment parameter corresponding to the cell reselection type includes a corresponding relationship between a bias value of the reference signal received power and/or a difference value between the bias value and the transmission power of the multicast service carrier sent by the neighboring cell and the transmission power of the main carrier of the neighboring cell;

It should be noted that the base station is a base station corresponding to a serving cell of the terminal, and the base station may communicate with other base stations, further obtain relevant information of an adjacent cell of the terminal, and transmit the relevant information of the adjacent cell to the terminal.

According to the embodiment of the invention, the cell reselection reference factor is sent according to the cell reselection type, so that the terminal can reselect the cell according to the cell reselection reference factor, thereby providing a precondition for cell reselection and ensuring the smooth cell reselection of the terminal.

Example two

As shown in fig. 2, an embodiment of the present invention provides a base station 20, including:

a first determining module 21, configured to determine a cell reselection type currently supported by the network;

a first sending module 22, configured to send the cell reselection reference factor to the terminal according to the cell reselection type, so that the terminal performs cell reselection according to the cell reselection reference factor.

Specifically, the first sending module 22 is configured to:

Specifically, when the cell reselection type is cell reselection based on reference signal received power, the preset information is a difference between transmission power of a multicast service carrier sent by an adjacent cell and transmission power of a main carrier of the adjacent cell;

Optionally, the base station 20 further includes:

Specifically, when the cell reselection type is cell reselection based on reference signal received power, the adjustment parameter corresponding to the cell reselection type includes calculating a corresponding relationship between an offset value of the reference signal received power and/or a difference between the offset value and a difference between transmission power of a multicast service carrier sent by an adjacent cell and transmission power of a main carrier of the multicast service carrier;

It should be noted that the embodiment of the base station is a base station corresponding to the above method embodiments one to one, and all implementation manners in the above method embodiments are applicable to the embodiment of the base station, and the same technical effect can be achieved.

EXAMPLE III

As shown in fig. 3, an embodiment of the present invention provides a base station, including:

a processor 31; and a memory 33 connected to the processor 31 through a bus interface 32, wherein the memory 33 is used for storing programs and data used by the processor 31 in executing operations, and when the processor 31 calls and executes the programs and data stored in the memory 33, the following processes are executed:

determining a cell reselection type currently supported by a network;

and sending the cell reselection reference factor to the terminal through the transceiver 34 according to the cell reselection type, so that the terminal reselects the cell according to the cell reselection reference factor.

It should be noted that the processor 31 is also configured to implement the functions of any other module of the base station.

It is noted that the transceiver 34 is connected to the bus interface 32 for transmitting the cell reselection reference factor under the control of the processor 31.

It should be noted that in fig. 3, the bus architecture may include any number of interconnected buses and bridges, with one or more processors represented by processor 31 and various circuits of memory represented by memory 33 being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 34 may be a number of elements, including a transmitter and a transceiver, providing a means for communicating with various other apparatus over a transmission medium. The processor 31 is responsible for managing the bus architecture and general processing, and the memory 33 may store data used by the processor 31 in performing operations.

Those skilled in the art will appreciate that all or part of the steps for implementing the above embodiments may be performed by hardware, or may be instructed to be performed by associated hardware by a computer program that includes instructions for performing some or all of the steps of the above methods; and the computer program may be stored in a readable storage medium, which may be any form of storage medium.

Example four

As shown in fig. 4, an embodiment of the present invention provides a cell reselection method, including:

step 41, receiving a cell reselection reference factor sent by a base station;

it should be noted that the cell reselection reference factor is determined and sent by the base station according to the cell reselection type, and the cell reselection reference factor is described in detail in the description of the base station side, and is not described in detail in this embodiment.

Step 42, acquiring a preset rule for the terminal to reselect the cell;

it should be noted that the preset rule is mainly divided into two types in summary, one is a cell for supporting the terminal preset service, and the other is the priority of all neighboring cells and the cell considering the terminal preset multicast service, and what kind of rule the terminal specifically uses may be set in advance by the network side and notified to the terminal.

And 43, determining the reselected cell according to the preset rule and the cell reselection reference factor.

In this step, the terminal reselects the cell according to the preset rule adopted by the network side for performing cell reselection and the cell reselection reference factor, and as can be seen from the first embodiment, when the terminal acquires the specific content of the preset information in the cell reselection reference factor, the terminal can determine the cell reselection type for performing cell reselection.

The implementation of step 43 is specifically described below according to different cell reselection types and preset rules for cell reselection, respectively.

When the cell reselection reference factor includes a difference between the transmission power of the multicast service carrier sent by the neighboring cell and the transmission power of the main carrier thereof (indicating that the cell reselection type is cell reselection based on the reference signal received power), and the preset rule is a cell supporting a preset service of the terminal, the step 43 includes:

step 4301, determining a first cell supporting a terminal preset service;

it should be noted that this step determines the set of cells supporting the multicast service of interest to the terminal.

Step 4302, measuring the reference signal received power of the carrier supporting the multicast service of each cell in the first cell;

step 4303, determining whether there is a second cell in the first cell, where the reference signal received power of the carrier supporting the multicast service meets the S criterion;

in this step, it is determined whether each cell in the first cell meets an S criterion, where the S criterion refers to whether the reference signal receiving power of the carrier supporting the multicast service can ensure normal transmission of the service, that is, whether the reference signal receiving power of the carrier supporting the multicast service is greater than or equal to a preset power is determined, and normal transmission of the service can be ensured only when the reference signal receiving power is greater than or equal to the preset power.

Step 4304, if there is the second cell, adding the reference signal received power of the carrier supporting the multicast service of each cell in the second cell to a difference corresponding to the reference signal received power to obtain a first reference signal received power, and using the cell with the largest first reference signal received power in the second cell as a reselected cell;

step 4305, if the second cell does not exist, measuring the reference signal received power of the main carrier of all the neighboring cells of the terminal, and taking the cell with the maximum reference signal received power of the main carrier in all the neighboring cells as the reselected cell.

It should be noted that, in this implementation, when a cell meeting the S criterion exists in a first cell supporting a preset service of a terminal, determining a reselected cell in the cell; and when the cells meeting the S criterion do not exist in the first cell, determining the reselected cell in all the adjacent cells of the terminal.

When the cell reselection reference factor includes a difference between the transmission power of the multicast service carrier sent by the neighboring cell and the transmission power of the main carrier thereof (indicating that the cell reselection type is cell reselection based on the reference signal received power), and the preset rule is priorities of all neighboring cells and a cell considering the preset multicast service for the terminal, the step 43 includes:

step 4306, obtaining an adjustment parameter corresponding to a cell reselection type sent by a base station, where the adjustment parameter corresponding to the cell reselection type includes a corresponding relationship between a bias value for calculating reference signal received power and/or a difference between the bias value and a difference between transmission power of a multicast service carrier sent by an adjacent cell and transmission power of a main carrier of the multicast service carrier;

it should be noted that, when the preset rule includes the priority of the cell supporting the terminal to preset the multicast service, at this time, the base station side may issue the adjustment parameter corresponding to the cell reselection type including the offset value of the received power of the reference signal and/or the corresponding relationship between the offset value and the difference between the transmission power of the multicast service carrier sent by the neighboring cell and the transmission power of the main carrier thereof, and at this time, the terminal only needs to receive the adjustment parameter corresponding to the cell reselection type.

Step 4307, determining a third cell supporting the terminal preset service;

Step 4308, measuring the reference signal received power of the carrier supporting the multicast service in each cell in the third cell;

step 4309, determining whether there is a fourth cell in the third cell, where the reference signal received power of the carrier supporting the multicast service meets an S criterion;

it should be noted that the implementation manner of this step is similar to the implementation manner of step 4303, and is not described here again.

Step 4310, adding the reference signal received power of the carrier supporting the multicast service of each cell in the fourth cell to the offset value corresponding to the reference signal received power to obtain a second reference signal received power;

step 4311, selecting the cell with the largest reference signal received power of the second reference signal received power in all the fourth cells, the reference signal received power of the carrier supporting the multicast service not belonging to the fourth cell in the third cell, and the reference signal received power of the main carrier in the cell not supporting the terminal preset service as the reselected cell.

It should be noted that, in this implementation, when there is a cell that meets the S criterion in a third cell that supports the terminal preset service, the reference signal received power of the cell is added to a corresponding offset value to increase the preferential selection probability of the cells, then all cells of the terminal are sorted according to the size of the reference signal received power, and the cell with the largest reference signal received power is selected as the cell reselected by the terminal.

When the cell reselection reference factor includes a frequency of a multicast service carrier sent by an adjacent cell (indicating that a cell reselection type is cell reselection based on reference signal reception quality), and the preset rule is a cell supporting a preset service of a terminal, the step 43 includes:

step 4312, determining a fifth cell supporting the terminal preset service;

Step 4313, measuring the reference signal receiving quality of the carrier supporting the multicast service in each cell in the fifth cell;

step 4314, determining whether a sixth cell whose reference signal reception quality of a carrier supporting the multicast service meets an S criterion exists in the fifth cell;

in this step, it is determined whether each cell in the fifth cell meets an S criterion, where the S criterion refers to whether the reference signal reception quality of the carrier supporting the multicast service can ensure normal transmission of the service, that is, whether the reference signal reception quality of the carrier supporting the multicast service is greater than or equal to a preset quality is determined, and normal transmission of the service can be ensured only when the reference signal reception quality is greater than or equal to the preset quality.

Step 4315, if the sixth cell exists, taking a cell with the highest reference signal reception quality of a carrier supporting the multicast service in the sixth cell as a reselected cell;

step 4316, if the sixth cell does not exist, measuring the reference signal received quality of the primary carrier of all the neighboring cells of the terminal, and taking the cell with the largest reference signal received quality in all the neighboring cells as the reselected cell.

It should be noted that, in this implementation, when a cell meeting the S criterion exists in a fifth cell supporting a preset service of the terminal, determining a reselected cell in the cell; and when the fifth cell does not have a cell meeting the S criterion, determining the reselected cell in all the adjacent cells of the terminal.

Fourthly, when the cell reselection reference factor includes the frequency of the multicast service carrier sent by the neighboring cell (indicating that the cell reselection type is cell reselection based on the reference signal reception quality), and the preset rule is the priorities of all neighboring cells and the cell considering the preset multicast service of the support terminal, the step 43 includes:

4317, acquiring an adjustment parameter corresponding to a cell reselection type sent by a base station, where the adjustment parameter corresponding to the cell reselection type includes an adjustment quantity for calculating a reference signal received quality and/or a correspondence between the adjustment quantity and the reference signal received quality, and a first preset number of neighboring cells preferred by a terminal;

it should be noted that, when the preset rule includes the priority of the cell that supports the terminal preset multicast service, the base station side may issue the adjustment parameter corresponding to the cell reselection type that includes the adjustment quantity for calculating the reference signal reception quality and/or the correspondence between the adjustment quantity and the reference signal reception quality and the first preset number of the neighboring cells preferred by the terminal, and at this time, the terminal only needs to receive the adjustment parameter corresponding to the cell reselection type.

4318, measuring the reference signal receiving quality of the main carriers of all the neighboring cells of the terminal;

4319, determining a first preset number of seventh cells meeting the S criterion according to the reference signal reception quality of the primary carriers of all the neighboring cells;

it should be noted that, during this step, the terminal may determine that the number of the seventh cells meeting the S criterion exceeds the first preset number, and at this time, the seventh cells should be sorted according to the reference signal received quality, and the seventh cell with the higher reference signal received quality is preferentially selected.

4320, measuring the receiving quality of the reference signal of the carrier wave of the multicast service preset by each cell sending terminal in the seventh cell;

step 4321, determining whether there is an eighth cell in the seventh cell, where the reference signal reception quality of the carrier supporting the multicast service meets the S criterion;

step 4322, when the eighth cell exists, adding the adjustment amount to the reference signal reception quality of the carrier supporting the multicast service in the eighth cell to obtain a first reference signal reception quality;

step 4323, regarding the largest cell of the first reference signal reception quality in the eighth cell and the reference signal reception quality of the carrier supporting the multicast service, which does not belong to the eighth cell, in the seventh cell as the cell after the terminal reselection.

It should be noted that, in this implementation, when there are cells meeting the S criterion in the first preset number of seventh cells meeting the S criterion, the reference signal received power of the cell is added with the corresponding adjustment amount to increase the preferential selection probability of the cells, then all the seventh cells are sorted according to the magnitude of the reference signal received quality, and the cell with the largest reference signal received quality is selected as the cell reselected by the terminal.

In practical applications, cell reselection methods applied to the base station and the terminal are illustrated as follows.

1. Cell reselection by terminal based on RSRP when serving cell receives multicast service of interest and neighbor cells also have multicast service of interest to terminal (informing terminal through SC-MCCH on base station of serving cell)

Step 1: the terminal resides in a serving cell, is in an idle state, receives multicast system messages broadcasted by a base station of the serving cell, SC-MCCH update indication and SC-MTCH corresponding to a multicast service in which the terminal is interested, information on the SC-MCCH includes but is not limited to a serving cell SC-MTCH configuration list and a neighbor cell list supporting the multicast service, wherein the neighbor cell list supporting the multicast service includes but is not limited to a physical cell identifier and primary carrier frequency information of a neighbor cell, the serving cell SC-MTCH configuration list includes but is not limited to multicast session information of the serving cell, G-RNTI corresponding to the serving cell SC-MTCH, serving cell SC-MTCH scheduling information, whether the neighbor cell supports the multicast indication information and difference information between the transmission power of a carrier of the multicast service transmitted by the neighbor cell and the transmission power of a primary carrier of the neighbor cell, and when the adjacent cell sends no difference between the transmission power of the multicast service carrier and the transmission power of the main carrier, not sending the difference information.

Step 2: when the terminal needs cell reselection, the terminal measures the RSRP of the main carrier waves of the neighboring adjacent cells; when the neighbor cell broadcasts the multicast service which the terminal is interested in and the active power of the carrier sending the multicast service is poor with the active power of the main carrier, the terminal calculates the RSRP according to the existing mechanism in the cell reselection sequencing, wherein the difference value of the transmitting power of the carrier sending the multicast service by the neighbor cell and the transmitting power of the main carrier is subtracted from the measured RSRP, and the terminal selects the sequenced optimal cell.

2. Cell reselection by terminal based on RSRP when serving cell has no multicast service of interest and neighbor cell has multicast service of interest to terminal (informing terminal through SC-MCCH on base station of serving cell)

Step 1: the terminal resides in the service cell, is in an idle state, receives the multicast system message, SC-MCCH and SC-MCCH updating indication broadcasted by the base station of the service cell, but has no multicast service which the terminal is interested in, the base station sends the multicast session information of the adjacent cell on the SC-MCCH and the difference value information of the transmitting power of the multicast service carrier and the transmitting power of the main carrier of the adjacent cell sent by the adjacent cell, when the transmitting power of the multicast service carrier sent by the adjacent cell has no difference value with the transmitting power of the main carrier, the difference value information is not sent.

3. RSRP-based cell reselection (informing a terminal through a system message broadcast by a base station serving a cell) when a neighbor cell has a multicast service of interest to the terminal

Step 1: the terminal resides in the serving cell, is in an idle state, and receives a system message broadcasted by a base station of the serving cell, where the system message includes, but is not limited to, multicast session information of an adjacent cell and difference information between transmission power of a multicast service carrier sent by the adjacent cell and transmission power of a main carrier of the adjacent cell, and when the adjacent cell sends no difference between the transmission power of the multicast service carrier and the transmission power of the main carrier, the difference information is not sent.

Step 2: when the terminal needs cell reselection, the terminal measures the RSRP of the main carrier waves of the neighboring adjacent cells; when the adjacent cell broadcasts the multicast service which the terminal is interested in and the active power of the carrier sending the multicast service is poor with the main carrier (namely, the carrier sending the multicast service has a difference value with the main carrier), the terminal calculates the RSRP in the cell reselection sequencing according to the existing mechanism, wherein the difference value between the transmitting power of the carrier sending the multicast service by the adjacent cell in the step one and the transmitting power of the main carrier is subtracted from the measured RSRP, and the terminal selects the sequenced optimal cell.

4. Cell reselection based on RSRP when the cell reselection range includes all adjacent cells, the cells supporting the multicast service in which the terminal is interested need to consider priority, and the active power of the carriers of the multicast service sent by the adjacent cells is poor with that of the main carriers

Step 1: the terminal resides in the serving cell, is in an idle state, and receives a system message broadcasted by a base station of the serving cell, wherein the system message includes but is not limited to an adjustment quantity used by the terminal for calculating the bias in the RSRP, and the adjustment quantity and the power difference between a carrier for sending the multicast service by an adjacent cell and a main carrier have a one-to-one mapping relation; and when the adjacent cell sends no difference between the transmission power of the multicast service carrier and the transmission power of the main carrier, not sending the difference information. The terminal and the network side receive and send the multicast session information sent by the neighboring cell and send the difference value between the transmission power of the multicast service carrier and the transmission power of the main carrier according to any scheme of embodiments 1 to 3.

Step 2: when a terminal needs cell reselection and the active power of a carrier and a main carrier of a multicast service sent by an adjacent cell is poor, the terminal reselection range includes all the adjacent cells, the terminal needs to consider a priority parameter of the cell supporting the multicast service interested by the terminal, wherein the priority parameter of the cell supporting the multicast service interested by the terminal can be a bias in calculating RSRP, when the terminal calculates the RSRP in cell reselection sequencing, the bias is adjusted based on the power difference between the carrier sending the multicast service by the adjacent cell and the main carrier, the adjustment method is to subtract the adjustment quantity of the system broadcast in the step 1, and the terminal selects the sequenced optimal cell.

5. Cell reselection based on RSRQ (notifying multicast session information of adjacent cell of terminal and frequency of multicast service carrier sent by adjacent cell through SC-MCCH on base station of serving cell)

Step 1: the terminal resides in a serving cell and is in an idle state, and receives multicast system messages, SC-MCCH update indications and SC-MTCH corresponding to multicast services in which the terminal is interested, wherein the information on the SC-MCCH includes but is not limited to a serving cell SC-MTCH configuration list and an adjacent cell list supporting the multicast services, the adjacent cell list supporting the multicast services includes but is not limited to physical cell identifiers and main carrier frequency information of the adjacent cells, the serving cell SC-MTCH configuration list includes but is not limited to multicast session information of the serving cell, G-RNTI corresponding to the serving cell SC-MTCH, serving cell SC-MTCH scheduling information, whether the adjacent cells support the multicast indication information and the frequency of the multicast service carrier waves transmitted by the adjacent cells; and when the adjacent cell transmits the multicast service in the main carrier wave of the adjacent cell, the carrier frequency information is not transmitted.

Step 2: when the cell reselection preferred selection range is a cell set supporting the multicast service which is interested by the terminal, the terminal measures the RSRQ on the carrier frequency of the service which is interested by the adjacent cell sending terminal, and selects the optimal cell after sequencing; and when no cell meeting the reselection requirement is in the cell set supporting the multicast service interested by the terminal, the terminal measures the RSRQ of the main carrier wave of the adjacent cell to reselect the cell.

6. Cell reselection based on RSRQ (notifying multicast session information of adjacent cell of terminal and frequency of multicast service carrier sent by adjacent cell through SC-MCCH on base station of serving cell)

Step 1: the terminal resides in a service cell, is in an idle state, receives multicast system information, SC-MCCH and SC-MCCH updating indication broadcasted by a base station of the service cell, and the base station sends multicast session information of an adjacent cell and the frequency of a multicast service carrier sent by the adjacent cell on the SC-MCCH; and when the adjacent cell transmits the multicast service in the main carrier wave of the adjacent cell, the carrier frequency information is not transmitted.

7. Cell reselection based on RSRQ (informing terminal of multicast session information of neighbor cell and frequency of sending the multicast service carrier by neighbor cell through system message broadcasted by base station of serving cell)

Step 1: the terminal resides in the serving cell, is in an idle state, and receives a system message broadcasted by a base station of the serving cell, wherein the system message includes but is not limited to multicast session information of an adjacent cell and the frequency of the multicast service carrier sent by the adjacent cell; and when the adjacent cell transmits the multicast service in the main carrier wave of the adjacent cell, the carrier frequency information is not transmitted.

Step 2: when the cell reselection preferred selection range is a cell set supporting the multicast service which is interested by the terminal, the terminal measures the RSRQ on the carrier frequency of the service which is interested by the adjacent cell sending terminal, and selects the optimal cell after sequencing; when the cell which meets the reselection requirement is not in the cell set supporting the multicast service which is interested by the terminal, the terminal measures the RSRQ of the main carrier wave of the adjacent cell to perform cell reselection

8. Cell reselection based on RSRQ when the cell reselection range includes all adjacent cells and the cells supporting the multicast service in which the terminal is interested need to consider priority

Step 1: the terminal resides in a serving cell, is in an idle state, and receives a system message broadcasted by a base station of the serving cell, wherein the system message includes but is not limited to an adjustment quantity used by the terminal for calculating RSRQ and a preferred carrier number N, the adjustment quantity and RSRP on carriers for sending multicast services by an adjacent cell have a one-to-one mapping relation, and the preferred cell number N is a non-negative integer which is the maximum cell number of subsequent cell reselection measurement; and when the adjacent cells all transmit the multicast service on the main carrier, not transmitting the preferred cell number N. The terminal and the network side receive and transmit the multicast session information of the neighbor cell and the frequency of the multicast service carrier transmitted by the neighbor cell according to any scheme of embodiment 5 to embodiment 7.

Step 2: when a terminal needs cell reselection and an adjacent cell sends multicast service on an auxiliary carrier, the terminal reselection range comprises all adjacent cells, the terminal measures the RSRQ of main carriers of all the adjacent cells, selects at most N cells in the cells meeting reselection conditions (S criteria), and measures the RSRQ of the carrier of the multicast service which is interested by the cell sending terminal; and when the carrier of the multicast service interested by the cell sending terminal meets the S criterion, adding the adjustment quantity for calculating the RSRQ received in the step 1 when calculating the R in the N cell sequences, and selecting the optimal cell after the sequence by the terminal.

It should be noted that the embodiment of the present invention provides a method for reselecting an NB-IoT terminal cell supporting multicast services under multiple carriers, which improves the efficiency of receiving multicast services after the terminal cell is reselected, reduces the power consumption of receiving multicast services by a terminal, and can better provide services for massive NB-IoT terminals supporting multicast services.

EXAMPLE five

As shown in fig. 5, an embodiment of the present invention provides a terminal 50, including:

a receiving module 51, configured to receive a cell reselection reference factor sent by a base station;

an obtaining module 52, configured to obtain a preset rule for a terminal to perform cell reselection;

and a second determining module 53, configured to determine a reselected cell according to the preset rule and the cell reselection reference factor.

Optionally, when the cell reselection reference factor includes a difference between the transmission power of the multicast service carrier sent by the neighboring cell and the transmission power of the main carrier thereof, and the preset rule is a cell supporting a preset service of the terminal, the second determining module 53 includes:

Optionally, when the cell reselection reference factor includes a difference between the transmission power of the multicast service carrier sent by the neighboring cell and the transmission power of the main carrier thereof, and the preset rule is priorities of all neighboring cells and a cell considering that the terminal supports preset multicast service, the second determining module 53 includes:

Optionally, when the cell reselection reference factor includes a frequency of a multicast service carrier sent by an adjacent cell, and the preset rule is a cell supporting a preset service of a terminal, the second determining module 53 includes:

Optionally, when the cell reselection reference factor includes a frequency of a neighboring cell sending a multicast service carrier, and the preset rule is priorities of all neighboring cells and a cell considering that a terminal supports preset multicast service, the second determining module 53 includes:

It should be noted that the embodiment of the terminal is a terminal corresponding to the above method embodiments one to one, and all implementation manners in the above method embodiments are applicable to the embodiment of the terminal, and the same technical effect can be achieved.

EXAMPLE six

As shown in fig. 6, an embodiment of the present invention provides a terminal, including:

a processor 61; and a memory 63 connected to the processor 61 through a bus interface 62, wherein the memory 63 is used for storing programs and data used by the processor 61 in executing operations, and when the processor 61 calls and executes the programs and data stored in the memory 63, the following processes are executed:

receiving, by transceiver 64, the cell reselection reference factor sent by the base station;

acquiring a preset rule for a terminal to reselect a cell;

Wherein the transceiver 64 is connected to the bus interface 62 for receiving the area reselection reference factor under control of the processor 61.

It should be noted that in fig. 6, the bus architecture may include any number of interconnected buses and bridges, with one or more processors represented by processor 61 and various circuits of memory represented by memory 63 being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 64 may be a number of elements, including a transmitter and a transceiver, providing a means for communicating with various other apparatus over a transmission medium. For different terminals, the user interface 65 may also be an interface capable of interfacing with a desired device, including but not limited to a keypad, display, speaker, microphone, joystick, etc. The processor 61 is responsible for managing the bus architecture and general processing, and the memory 63 may store data used by the processor 61 in performing operations.

While the preferred embodiments of the present invention have been described, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the following claims.

Claims

1. A method of cell reselection, comprising:

determining a cell reselection type currently supported by a network;

sending a cell reselection reference factor to a terminal according to the cell reselection type, so that the terminal reselects the cell according to the cell reselection reference factor;

according to the cell reselection type, sending an adjustment parameter corresponding to the cell reselection type to the terminal through a second system broadcast message;

when there is a cell satisfying the S criterion among cells supporting the terminal multicast service,

when the cell reselection type is cell reselection based on reference signal receiving power, the adjustment parameter corresponding to the cell reselection type comprises a corresponding relation of calculating a bias value of the reference signal receiving power and/or a difference value between the bias value and the transmitting power of a multicast service carrier sent by an adjacent cell and the transmitting power of a main carrier of the adjacent cell;

2. The cell reselection method of claim 1, wherein the step of transmitting the cell reselection reference factor to the terminal comprises:

3. The cell reselection method according to claim 2, wherein when the cell reselection type is cell reselection based on reference signal received power, the preset information is a difference between a transmission power of a neighboring cell transmitting a multicast service carrier and a transmission power of a main carrier thereof;

4. A base station, comprising:

the first sending module is used for sending the cell reselection reference factor to the terminal according to the cell reselection type, so that the terminal reselects the cell according to the cell reselection reference factor;

a second sending module, configured to send, according to the cell reselection type, an adjustment parameter corresponding to the cell reselection type to the terminal through a second system broadcast message;

5. The base station of claim 4, wherein the first sending module is configured to:

6. The base station of claim 5, wherein when the cell reselection type is cell reselection based on reference signal received power, the preset information is a difference between a transmission power of a neighboring cell transmitting a multicast service carrier and a transmission power of a primary carrier thereof;

7. A method of cell reselection, comprising:

receiving a cell reselection reference factor sent by a base station;

acquiring a preset rule for a terminal to reselect a cell;

determining a reselected cell according to the preset rule and the cell reselection reference factor;

when the cell reselection reference factor includes a difference between the transmission power of a multicast service carrier sent by an adjacent cell and the transmission power of a main carrier of the adjacent cell, and the preset rule is a cell supporting a preset service of a terminal, the step of determining the reselected cell according to the preset rule and the cell reselection reference factor includes:

determining a first cell supporting a preset service of a terminal;

if the second cell does not exist, measuring the reference signal receiving power of the main carrier waves of all the adjacent cells of the terminal, and taking the cell with the maximum reference signal receiving power of the main carrier waves in all the adjacent cells as the reselected cell;

when the cell reselection reference factor includes a frequency of a multicast service carrier sent by an adjacent cell and the preset rule is a cell supporting a preset service of a terminal, the step of determining the reselected cell according to the preset rule and the cell reselection reference factor includes:

determining a fifth cell supporting a preset service of the terminal;

8. The cell reselection method according to claim 7, wherein, when the cell reselection reference factor includes a difference between a transmission power of a neighboring cell for sending a multicast service carrier and a transmission power of a main carrier thereof, and the preset rule is priorities of all neighboring cells and a cell considering a preset multicast service for a terminal, the step of determining the reselected cell according to the preset rule and the cell reselection reference factor comprises:

determining a third cell supporting a preset service of the terminal;

9. The cell reselection method according to claim 7, wherein when the cell reselection reference factor includes a frequency of a neighboring cell transmitting a multicast service carrier, and the preset rule is priorities of all neighboring cells and a cell considering a preset multicast service supporting a terminal, the step of determining the reselected cell according to the preset rule and the cell reselection reference factor comprises:

10. A terminal, comprising:

a second determining module, configured to determine a reselected cell according to the preset rule and the cell reselection reference factor;

when the cell reselection reference factor includes a difference between the transmission power of a multicast service carrier sent by an adjacent cell and the transmission power of a main carrier of the adjacent cell, and the preset rule is a cell supporting a preset service of a terminal, the second determining module includes:

a third determining unit, configured to measure reference signal received powers of main carriers of all neighboring cells of the terminal if the second cell does not exist, and use a cell with a largest reference signal received power of a main carrier in all neighboring cells as a reselected cell;

when the cell reselection reference factor includes a frequency of a multicast service carrier sent by an adjacent cell and the preset rule is a cell supporting a preset service of a terminal, the second determining module includes:

11. The terminal according to claim 10, wherein when the cell reselection reference factor includes a difference between a transmission power of a neighboring cell for sending a multicast service carrier and a transmission power of a primary carrier thereof, and the preset rule is priorities of all neighboring cells and a cell considering a preset multicast service for the terminal, the second determining module includes:

12. The terminal according to claim 10, wherein when the cell reselection reference factor includes a frequency of a neighboring cell transmitting a multicast service carrier, and the preset rule is priorities of all neighboring cells and a cell considering a preset multicast service for the terminal, the second determining module comprises: