CN112118608A - Method, device and base station for switching cell by terminal - Google Patents

Abstract

The invention discloses a method, a device and a base station for a terminal to switch a cell. The method provided by the invention enables the source base station to randomly access the target base station for a period of time after the source base station sends a handover command to the eMTC terminal and responds that the narrowband where the RAR is located is not scheduled. It can reduce the interference of the source base station to the handover cell of the eMTC terminal and improve the access success rate, thereby effectively solving the problem of reducing the handover success rate of the eMTC terminal due to the interference of the source cell in the prior art.

Description

Method, device and base station for terminal switching cell

technical field

The present invention relates to the field of communications, and in particular, to a method, a device and a base station for a terminal to switch cells.

Background technique

3GPP (3rd Generation Partnership Project) defines an enhanced machine communication (enhanced Machine Type Communication, eMTC) protocol in Release 13 to support the large-connection wide area network Internet of Things.

The specific handover process of the eMTC terminal between cells is shown in Figure 1. According to Figure 1, in the prior art, after receiving the confirmation of the handover request sent by the target base station, the source base station directly sends a handover command to the eMTC terminal, and then the eMTC The terminal initiates random access to the target base station, and this access method will affect the success rate of eMTC terminal handover.

SUMMARY OF THE INVENTION

The present invention provides a method, a device and a base station for a terminal to switch a cell, so as to solve the problem of a low handover success rate when a terminal switches a cell in the prior art.

In order to solve the above technical problems, in the first aspect, the present invention provides a method for a terminal to switch a cell, which is applied to a source base station. handover command, and close the scheduling service on the narrowband where the preset random access response RAR of the source base station is located, and restart the scheduling service on the narrowband where the preset RAR is located after a predetermined time; wherein, the narrowband where the preset RAR is located is the narrowband where the target base station and the terminal RAR are located.

In a second aspect, the present invention provides an apparatus for a terminal to switch cells, which is applied to a source base station. The apparatus includes: a receiving unit, configured to receive a handover request response sent by a target base station; a processing unit, used in the receiving unit After receiving the handover request response sent by the target base station, send a handover command to the terminal in the handover cell, close the scheduling service on the narrowband where the source base station preset random access response RAR is located, and restart after a predetermined time The scheduling service on the narrowband where the preset RAR is located; wherein, the narrowband where the preset RAR is located is the narrowband where the target base station and the C terminal RAR are located.

In a third aspect, the present invention provides a computer-readable storage medium, characterized in that, a computer program is stored on the computer storage medium, and when the computer program is executed by a processor, any one of the cell switching of the terminal can be realized. steps of the method.

In a fourth aspect, the present invention provides a base station, the base station comprising: a memory, a processor, and a computer program stored on the memory and executable on the processor, the computer program being executed by the processor The steps of any of the described methods are implemented when executed.

In the method provided by the present invention, after the source base station sends a handover command to the terminal, the source base station does not schedule services in the narrowband where the target base station random access response (Random Access Response, RAR) is located for a period of time, so as to reduce the interference of the source base station to the terminal switching cell , improving the access success rate, thereby effectively solving the problem of reducing the terminal handover success rate due to the interference of the source cell in the prior art.

Description of drawings

1 is a schematic flowchart of a method for a terminal to switch cells in the prior art;

2 is a schematic flowchart of a method for a terminal to switch cells according to an embodiment of the present invention;

3 is a schematic diagram of narrowband division in an embodiment of the present invention;

4 is a schematic flowchart of another method for a terminal to switch cells according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of an apparatus for switching a cell by a terminal according to an embodiment of the present invention.

Detailed ways

In order to solve the problem in the prior art that the terminal handover success rate is low due to the interference of the source cell, the present invention provides a method, a device and a base station for a terminal to switch a cell. The present invention is further described below with reference to the drawings and embodiments. Detailed description. It should be understood that the specific embodiments described herein are only used to illustrate the present invention, but not to limit the present invention.

The first embodiment of the present invention provides a method for a terminal to switch cells. The flow of the method is shown in FIG. 2 , including steps S201 to S203:

S201, receiving a handover request response sent by a target base station;

Before this step, the source base station must first determine whether the handover condition is met, and if the handover condition is met, it sends a handover request to the target base station, and then the target base station returns a handover request response to the source base station.

It should be noted that, in the embodiment of the present invention, the handover request response returned by the target base station to the source base station includes at least the narrowband position of the RAR when the terminal accesses the target base station, that is, the handover request response returned by the target base station to the source base station must carry the target base station. The narrowband location of the RAR used by the base station to access the terminal for the terminal to access the target base station.

S202, sending a handover command to the terminal in the handover cell, and closing the scheduling service on the narrowband where the source base station preset random access response RAR is located;

The handover command sent by the source base station to the terminal includes basic information about the terminal accessing the target cell, such as the target cell ID, the narrowband position of the RAR when the terminal accesses the target base station, and so on.

Wherein, in the embodiment of the present invention, the narrowband where the preset RAR is located is the narrowband where the target base station and the terminal RAR are located.

S203, after a predetermined time, restart the scheduling service on the narrowband where the preset RAR is located.

In specific implementation, the predetermined time in this embodiment of the present invention is less than the preset cell switching time, and the preset cell switching time is a preset value of the time it takes for the terminal to switch cells. When the time value is reached, the terminal will be triggered A connection request is initiated to all switchable cells to ensure that the terminal can access the cell.

That is to say, in the embodiment of the present invention, after the source base station sends a handover command to the terminal, the source base station does not schedule services in the narrowband where the target base station random access response is located for a period of time, so as to reduce the interference of the source base station to the terminal handover cell, thereby reducing the interference of the source base station to the terminal handover cell. The success rate of terminal access is improved, thereby effectively solving the problem of reducing the success rate of terminal handover due to the interference of the source cell in the prior art.

It should be noted that the methods described in the embodiments of the present invention can be applied to an enhanced Machine Type Communication (eMTC) terminal. Of course, those skilled in the art can also apply the methods described in the embodiments of the present invention to actual needs. Cell handover of other terminals such as 5G and 6G.

The following will mainly take the eMTC terminal as an example to describe the method in the embodiment of the present invention in detail:

其中

表示整个系统带宽的RB数。以5M带宽为例，eMTC的窄带划分如图3所示。Since the eMTC terminal performs resource allocation in one narrowband, all narrowbands are 6 resource blocks (RB, Resource Block) in size. The total number of downlink narrowbands is

in

Indicates the number of RBs in the entire system bandwidth. Taking 5M bandwidth as an example, the narrowband division of eMTC is shown in Figure 3.

The MTCPhysical Downlink Control Channel (MPDCCH) of the Random Access Response (RAR) of the eMTC terminal is fixed in one or two narrowband scheduling, determined by the high-level parameter mpdcch-NarrowbandsToMonitor-r13, when the configuration is 2 The time is determined according to Table 1.

Table 1 MPDCCH narrowband index of RAR.

Based on this point, the embodiment of the present invention reduces the interference of the source base station to the eMTC terminal switching cell by closing the scheduling service on the source base station, the target base station and the narrowband where the eMTC terminal RAR is located, so that the eMTC terminal can smoothly switch to the target base station , thereby improving the success rate of the eMTC terminal switching cells.

Generally speaking, since the handover occurs at the edge of two cells, after receiving the handover command from the source cell, the eMTC terminal will be strongly interfered by the source cell in the process of initiating random access to the target cell. After the source base station sends the handover command to the eMTC terminal, for a period of time, the source base station does not schedule services in the narrowband where the target base station Random Access Response (RAR) is located, so as to reduce the source base station's interference to the eMTC terminal switching cells, The access success rate is improved, thereby effectively solving the problem in the prior art that the handover success rate of the eMTC terminal is reduced due to the interference of the source cell.

In step S102 of the embodiment of the present invention, the scheduling service on the narrowband where the preset RAR of the source base station is located is closed, and after a predetermined time, the scheduling service on the narrowband where the preset RAR is located is restarted, including:

After closing the scheduling service on the narrowband where the preset RAR is located, the source base station starts a timer, and after the timer reaches the predetermined time, restarts the scheduling service on the narrowband where the RAR is located.

Specifically, in the embodiment of the present invention, a timer is used to monitor the time when the source base station closes the scheduling service in the narrowband where the preset RAR is located, and when the timer reaches the predetermined time, it will reopen the narrowband where the preset RAR is located. scheduling business.

Of course, those skilled in the art can also monitor the time for closing the scheduling service on the narrowband where the RAR is located by other means, which is not specifically limited in the present invention.

The embodiments of the present invention are aimed at the fact that handover occurs at the edge of two cells. After receiving the handover command from the source cell, the eMTC terminal initiates random access to the target cell. At this time, the source cell is a strong interference to the eMTC terminal, which affects the When the eMTC terminal accesses the target cell, the RAR is received, which further affects the handover success rate of the eMTC terminal.

In order to improve the handover success rate of the eMTC terminal in the above scenario, in the embodiment of the present invention, during the handover process of the eMTC terminal, after the source cell issues the handover command, the narrowband where the RAR of the target cell is located does not schedule services for a period of time, so as to reduce the need for the terminal to access the target. The interference of the cell increases the success rate of access.

Specifically, it includes: the source cell receives the handover request confirmation sent by the target cell, the source cell sends a handover command to the terminal, and the source cell starts a timer T. Step 4: Before the timer T expires, the source cell does not schedule services in the narrowband where the RAR of the target cell is located. , after the timer T times out, the service can be scheduled in the narrowband where the RAR of the target cell is located.

The method described in the embodiment of the present invention will be explained and described in detail below with reference to FIG. 4 :

FIG. 4 is a schematic diagram of inter-cell handover. After the source cell issues a handover command, it does not schedule services in the narrowband location of the RAR of the target cell for a period of time. details as follows:

Step 401: The source base station initiates a handover request to the target base station.

In this step, after judging that the terminal meets the handover condition, the source base station initiates a handover request to the target base station.

Step 402: The source base station receives the handover request response sent by the target base station.

In this step, the target base station sends a handover request response to the source base station, which includes the narrowband position of the RAR when the eMTC terminal accesses the target base station, which is marked as NB1 here, and the position of NB1 is recorded.

Step 403: The source base station sends a handover command to the terminal.

In this step, the handover command includes basic information of the eMTC terminal accessing the target cell. After receiving the handover command, the terminal initiates random access to the target cell.

Step 404: The source base station starts the timer T (ie, the predetermined time value mentioned above in the embodiment of the present invention).

In this step, the suggested value of the timer T does not exceed the handover timer (that is, the preset handover cell time value mentioned above in the embodiment of the present invention).

Step 405 : determine whether the timer has timed out, if it timed out, go to step 407 ; if not, go to step 406 .

Step 406: Scheduling services in the narrowband where the RAR of the target cell is not located.

If the timer T does not expire, the service is not scheduled on NB1. The next subframe continues to step 405 to determine whether the timer has timed out.

Step 407: Restore the normal scheduling service in the narrowband where the RAR of the target cell is located.

Step 408: End.

Using the method of the present invention, through the interference coordination method between the source cell and the target cell, when the eMTC terminal randomly accesses the target cell during the handover process, the narrowband interference where the RAR is located is reduced, so the success rate of the eMTC handover of the system is improved, and the user experience.

The second embodiment of the present invention provides an apparatus for a terminal to switch cells, referring to FIG. 5 , which is applied to a source base station and includes:

a receiving unit, configured to receive a handover request response sent by the target base station;

The processing unit is configured to send a handover command to the terminal in the handover cell after the receiving unit receives the handover request response sent by the target base station, and close the scheduling on the narrowband where the source base station preset random access response RAR is located service, after a predetermined time, restart the scheduling service on the narrowband where the preset RAR is located;

The narrowband where the preset RAR is located is the narrowband where the target base station and the terminal RAR are located.

In addition, the handover request response in the embodiment of the present invention carries the position of the narrowband where the terminal accesses the RAR of the target base station. And the handover command carries the target base station information and the narrowband position where the terminal accesses the target base station preset RAR.

In the embodiment of the present invention, after the source base station sends the handover command to the terminal, after the receiving unit receives the handover request response sent by the target base station, the processing unit does not schedule services in the narrowband where the target base station RAR is located for a period of time, so as to reduce the source base station The interference to the terminal switching cell improves the access success rate, thereby effectively solving the problem of reducing the terminal switching success rate due to the interference of the source cell in the prior art.

In specific implementation, the processing unit in the embodiment of the present invention starts a timer after closing the scheduling service on the narrowband where the source base station presets the RAR, and restarts the RAR after the timer reaches the predetermined time. The scheduling service on the narrowband where it is located.

Specifically, in the embodiment of the present invention, a timer is used to monitor the time when the source base station closes the scheduling service in the narrowband where the preset RAR is located, and when the timer reaches the predetermined time, it will reopen the narrowband where the preset RAR is located. scheduling business.

During specific implementation, the predetermined time in this embodiment of the present invention is less than the preset handover cell time.

It should be noted that the methods described in the embodiments of the present invention can be applied to eMTC terminals. Of course, those skilled in the art can also apply the methods described in the embodiments of the present invention to cell handovers of other terminals such as 5G and 6G according to actual needs. superior.

The following will mainly take the eMTC terminal as an example to describe the embodiments of the present invention in detail:

其中

表示整个系统带宽的RB数。以5M带宽为例，eMTC的窄带划分如图3所示。Since the eMTC terminal performs resource allocation in one narrowband, all narrowbands are 6 resource blocks (RB, Resource Block) in size. The total number of downlink narrowbands is

in

Indicates the number of RBs in the entire system bandwidth. Taking 5M bandwidth as an example, the narrowband division of eMTC is shown in Figure 3.

The MTCPhysical Downlink Control Channel (MPDCCH) of the Random Access Response (RAR) of the eMTC terminal is fixed in one or two narrowband scheduling, determined by the high-level parameter mpdcch-NarrowbandsToMonitor-r13, when the configuration is 2 The time is determined according to Table 1.

Table 1 MPDCCH narrowband index of RAR.

Based on this point, the embodiment of the present invention reduces the interference of the source base station to the eMTC terminal switching cell by closing the scheduling service on the source base station, the target base station and the narrowband where the eMTC terminal RAR is located, so that the eMTC terminal can smoothly switch to the target base station , thereby improving the success rate of the eMTC terminal switching cells.

Generally speaking, since the handover occurs at the edge of two cells, after receiving the handover command from the source cell, the eMTC terminal will be strongly interfered by the source cell in the process of initiating random access to the target cell. After the source base station sends the handover command to the eMTC terminal, the source base station does not schedule services in the narrowband where the target base station RAR is located for a period of time, so as to reduce the interference of the source base station to the eMTC terminal switching cell and improve the access success rate, thus effectively solving the problem. In the prior art, the handover success rate of the eMTC terminal is reduced due to the interference of the source cell.

The relevant content of the embodiment of the present invention can be understood with reference to the first embodiment of the present invention, and will not be discussed in detail here.

A third embodiment of the present invention provides a computer-readable storage medium, where a computer program is stored on the computer storage medium, and when the computer program is executed by a processor, any one of the first embodiments of the present invention is implemented. Steps of a method for a terminal to switch cells. The relevant content of the embodiment of the present invention can be understood with reference to the first embodiment of the present invention, and will not be discussed in detail here.

A fourth embodiment of the present invention provides a base station, the base station includes: a memory, a processor, and a computer program stored on the memory and executable on the processor, the computer program being executed by the processor When executed, the steps of any one of the methods described in the first embodiment of the present invention are implemented. The relevant content of the embodiment of the present invention can be understood with reference to the first embodiment of the present invention, and will not be discussed in detail here.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, and therefore, the scope of the present invention should not be limited to the above-described embodiments.

Claims (10)

1. A method for a terminal to switch a cell, wherein the method is applied to a source base station, the method comprising: After receiving the handover request response sent by the target base station, send a handover command to the terminal in the handover cell, and close the scheduling service on the narrowband where the source base station preset random access response RAR is located, and restart the preset after a predetermined time. Set the scheduling service on the narrowband where the RAR is located; The narrowband where the preset RAR is located is the narrowband where the target base station and the terminal RAR are located. 2. The method according to claim 1, wherein the scheduling service on the narrowband where the preset RAR of the source base station is located is closed, and after a predetermined time, the scheduling service on the narrowband where the preset RAR is located is restarted, comprising: After closing the scheduling service on the narrowband where the preset RAR is located, the source base station starts a timer, and after the timer reaches the predetermined time, restarts the scheduling service on the narrowband where the RAR is located. 3. The method of claim 1 or 2, wherein The predetermined time is less than the preset handover cell time. 4. The method of claim 1 or 2, wherein The handover request response carries the position of the narrowband where the terminal accesses the target base station RAR. 5. The method of claim 1 or 2, wherein The handover command carries the target base station information and the narrowband position where the terminal accesses the target base station preset RAR. 6. An apparatus for a terminal to switch cells, characterized in that, applied to a source base station, the apparatus comprising: a receiving unit, configured to receive a handover request response sent by the target base station; A processing unit, configured to send a handover command to the terminal in the handover cell after the receiving unit receives the handover request response sent by the target base station, and turn off the source base station preset random access response RAR on the narrowband the scheduling service, after a predetermined time, restart the scheduling service on the narrowband where the preset RAR is located; The narrowband where the preset RAR is located is the narrowband where the target base station and the terminal RAR are located. 7. The apparatus of claim 6, wherein The processing unit is further configured to start a timer after closing the scheduling service on the narrowband where the source base station presets the RAR, and restart the scheduling service on the narrowband where the RAR is located after the timer reaches the predetermined time. 8. The device of claim 6 or 7, wherein The predetermined time is less than the preset handover cell time. 9. A computer-readable storage medium, wherein a computer program is stored on the computer storage medium, and when the computer program is executed by a processor, the terminal switching according to any one of claims 1 to 5 is realized The steps of the cell method. 10. A base station, characterized in that the base station comprises: a memory, a processor, and a computer program stored on the memory and executable on the processor, when the computer program is executed by the processor The steps of implementing the method of any one of claims 1 to 5 are carried out.

Images