WO2012167497A1

WO2012167497A1 - Sending method, enb and user equipment

Info

Publication number: WO2012167497A1
Application number: PCT/CN2011/077957
Authority: WO
Inventors: 王金灵; 刘文济
Original assignee: 华为技术有限公司
Priority date: 2011-08-03
Filing date: 2011-08-03
Publication date: 2012-12-13
Also published as: CN103535101A; CN103535101B

Abstract

Provided are a sending method, eNB and user equipment. The sending method includes: an eNB counting the load of each PRACH subframe; sending first indication information to user equipment when there are at least two PRACH subframes with different loads, with the first indication information being used for indicating at least one PRACH subframe having a load less than a preset threshold; or sending second indication information to the user equipment when there are no PRACH subframes with different loads, with the second indication information being used for indicating that the user equipment selects a PRACH subframe randomly with equal probability. The present invention can balance the load of the PRACH resource and maximize the capacity of the PRACH.

Description

Transmission method, base station and user equipment

The present invention relates to the field of communications technologies, and in particular, to a transmitting method, a base station, and a user equipment. Background technique

Random access is a very important process for establishing uplink synchronization and connection between user equipment (UE) and evolved NodeB (eNB) in a mobile communication system. Random access is divided into initial random access and non-initial random access.

The non-initial random access includes a random access triggered by a handover (Handover, HO) and a physical downlink control channel order (PDCCH Order). For the HO-triggered random access and the PDCCH Order-triggered random access, the eNB specifies a Physical Random Access Channel (PRACH) mask index (PRACH Mask Index) in the HO signaling and the PDCCH Order signaling. And the preamble index (Preamble Index), so that the UE does not need to reselect the Preamble Index and the PRACH resource, and can directly access the resource specified by the PRACH Mask Index and the Preamble Index specified by the eNB.

In the process of implementing the present invention, the inventor has found that under the Long Term Evolution (LTE) Time Division Duplexing (TDD) system, existing random access initiated by eNBs such as HO and PDCCH Order will be generated. PRACH resource load imbalance problem. Summary of the invention

The present invention provides a transmission method, a base station, and a user equipment, to solve the problem of imbalance of PRACH resource load generated by existing random access.

An aspect of the present invention provides a transmitting method, including: The base station calculates the load of each physical random access channel PRACH subframe;

When there are at least two PRACH subframes with different loads, the base station sends first indication information to the user equipment, where the first indication information is used to indicate that the load is less than a predetermined threshold, at least one PRACH subframe; or

When there is no PRACH subframe with different loads, the base station sends second indication information to the user equipment, where the second indication information is used to indicate that the user equipment randomly selects a PRACH subframe.

Another aspect of the present invention also provides a transmitting method, including:

The user equipment receives signaling sent by the base station;

When the signaling carries the first indication information, determining whether the base station specifies a preamble index for the user equipment, and if not, the user equipment randomly selects a preamble index of the user equipment, and in the foregoing And transmitting, by the indication, the preamble index of the user equipment, where the first indicator information is used to specify the at least one PRACH subframe whose load is less than a predetermined threshold; or

When the signaling carries the second indication information, determining whether the base station specifies a preamble index for the user equipment, and if yes, the user equipment randomly and pseudo-selects a PRACH subframe in a valid PRACH subframe, And transmitting, by using the selected PRACH subframe, a preamble index that is specified by the base station for the user equipment, where the second indication information is used to indicate that the user equipment randomly selects a PRACH subframe according to a probability.

Another aspect of the present invention also provides a base station, including:

a statistic unit, configured to collect a load of a PRACH subframe of each physical random access channel, and a sending unit, configured to send, to the user equipment, first indication information, when the at least two PRACH subframes with different loads are present, the first The indication information is used to indicate that the load is less than a predetermined threshold, or the second indication information is sent to the user equipment when the PRACH subframes with different loads are not present, where the second indication information is used to indicate the user The device randomly selects a PRACH subframe with equal probability. Another aspect of the present invention also provides a user equipment, including:

a receiving unit, configured to receive signaling sent by the base station;

a determining unit, configured to determine, when the signaling carries the first indication information or the second indication information, whether the base station specifies a preamble index for the user equipment;

a selecting unit, configured to: when the determining unit carries the first indication information, after the determining unit determines that the base station does not specify a preamble index for the user equipment, randomly select a preamble index of the user equipment; or When the signaling carries the second indication information, after the determining unit determines that the base station has specified a preamble index for the user equipment,

Selecting a PRACH subframe randomly and probabilistically in the PRACH subframe;

a sending unit, configured to: when the signaling carries the first indication information, a preamble index of the first indication information user equipment, where the first indication information is used to specify that the load is less than a predetermined threshold, at least one PRACH sub a frame; or, when the signaling carries the second indication information, sending, by using a PRACH subframe selected by the selecting unit, a preamble index specified by the base station for the user equipment, where the second indication information is used. Instructing the user equipment to randomly select a PRACH subframe.

In the foregoing technical solution, when there are at least two PRACH subframes with different loads, the base station sends, to the user equipment, first indication information for indicating at least one PRACH subframe whose load is less than a predetermined threshold, so that the user equipment may be in the first indication. The preamble index is sent on the subframe indicated by the information; thus, the load of the balanced PRACH resource can be realized, and the capacity of the PRACH is maximized. DRAWINGS

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief description of the drawings used in the embodiments or the prior art description will be briefly described below. Obviously, the drawings in the following description It is a certain embodiment of the present invention, and other drawings can be obtained from those skilled in the art without any creative work. FIG. 1 is a flowchart of a method according to an embodiment of the present invention;

2 is a flowchart of a method according to another embodiment of the present invention;

3 is a flowchart of a method according to still another embodiment of the present invention;

4 is a flowchart of a method according to still another embodiment of the present invention;

FIG. 5 is a schematic diagram of a base station according to an embodiment of the present invention;

FIG. 6 is a schematic diagram of a base station according to another embodiment of the present invention; FIG.

FIG. 7 is a schematic diagram of a user equipment according to an embodiment of the present invention. detailed description

The technical solutions in the embodiments of the present invention are clearly and completely described in the following with reference to the accompanying drawings in the embodiments of the present invention. It is a partial embodiment of the invention, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

FIG. 1 is a flowchart of a method according to an embodiment of the present invention. As shown in FIG. 1, the method may include:

Step 101: The base station calculates the load of each PRACH subframe.

Step 102: When there are at least two PRACH subframes with different loads, the base station sends first indication information to the UE, where the first indication information is used to indicate that the load is less than a predetermined threshold, at least one PRACH subframe; or when there is no load When the PRACH subframe is different, the base station sends the second indication information to the UE, where the second indication information is used to indicate that the UE randomly selects the PRACH subframe by random equal probability.

In the foregoing step 101, the base station may further determine whether there are at least two PRACH subframes with different loads. According to different determination results, the base station may select to perform different processing in step 102, that is, send different information.

In this embodiment, before the base station sends the first indication information to the user equipment, the base station may select The at least one PRACH subframe with the load being less than the predetermined threshold is configured to set the first indication information according to the PRACH resource number corresponding to the at least one PRACH subframe whose load is less than a predetermined threshold. Specifically, the foregoing first indication information may be a PRACH mask index.

In an implementation manner of this embodiment, the first indication information and the third indication information are carried in the same signaling, where the third indication information is used to indicate that the base station does not specify a preamble index for the UE.

In another implementation manner of this embodiment, the second indication information and the fourth indication information are carried in the same signaling, where the fourth indication information is used to indicate that the base station has specified a preamble index for the UE. The second indication information is a PRACH mask index, and the value of the second indication information is different from the value of the first indication information. For example, the value of the second indication information may be "0", and the value of the first indication information may be a positive integer.

In the foregoing embodiment, when there are at least two PRACH subframes with different loads, the base station sends, to the UE, first indication information, which is used to indicate that the load is less than a predetermined threshold, so that the UE may be in the first indication information. The preamble index is sent on the indicated subframe; thus, the load of the balanced PRACH resource can be realized, and the capacity of the PRACH is maximized. Thereby, the load of the balanced PRACH resources can be realized, and the capacity of the PRACH can be maximized.

FIG. 2 is a flowchart of a method according to another embodiment of the present invention. As shown in FIG. 2, the method may include:

Step 201: The UE receives signaling sent by the base station.

Step 202: When the signaling carries the first indication information, determine whether the base station specifies a preamble index for the UE, and if not, the UE randomly selects a preamble index of the UE, and the PRACH subframe specified by the first indication information And sending, by the UE, a preamble index, where the first indication information is used to specify that the load is less than a predetermined threshold, or when the signaling carries the second indication information, determining whether the base station specifies a preamble index for the UE If yes, the UE randomly selects a PRACH subframe in a valid PRACH subframe, and uses the selected PRACH subframe to send a preamble index that the base station specifies for the UE, where the second indication information is used to indicate the UE. The random equal probability is selected for the PRACH subframe. Specifically, in this embodiment, when the signaling carries the first indication information, if the signaling further carries the third indication information, the UE may determine that the base station does not specify a preamble index for the UE, where the third indication information is It is used to indicate that the base station does not specify a preamble index for the UE. In this embodiment, the first indication information may be a PRACH mask index, and the third indication information may be a preamble index.

When the signaling carries the second indication information, if the signaling further carries the fourth indication information, the UE may determine that the base station has specified a preamble index for the UE, and the fourth indication information is used to indicate that the base station has specified a preamble for the UE. index. In this embodiment, the second indication information is a PRACH mask index, and the value of the second indication information is different from the value of the first indication information. The fourth indication information is a preamble index, and the value of the fourth indication information is The value of the third indication information is different. For example, the value of the second indication information may be "0", and the value of the first indication information may be a positive integer. The value of the third indication information may be "0", and the value of the fourth indication information may be a positive integer.

In the above embodiment, after receiving the signaling sent by the base station, the UE may send the preamble index on the PRACH subframe indicated by the first indication information; thereby, the load of the balanced PRACH resource may be balanced, and the capacity of the PRACH is maximized.

In the following description of the embodiments of the present invention, the base station is used as the eNB, and the foregoing signaling is the HO signaling or the PDCCH Order signaling as an example.

FIG. 3 is a flowchart of a method according to still another embodiment of the present invention. As shown in FIG. 3, the method may include:

Step 301: The eNB counts the load of each PRACH subframe.

Specifically, the eNB may count the load of each PRACH subframe starting from the time when the cell served by the eNB is started.

The embodiment of the present invention does not limit the manner in which the eNB counts the load of each PRACH subframe, as long as the load of each PRACH subframe can be counted.

Step 302: When there are at least two PRACH subframes with different loads, the eNB selects a small load. The first indication information is set according to the PRACH resource number corresponding to the at least one PRACH subframe whose load is less than a predetermined threshold, in the at least one PRACH subframe of the predetermined threshold.

Specifically, the first indication information is used to indicate that the load is less than a predetermined threshold, and the first indication information may be a PRACH mask index, and the value of the first indication information may be a positive integer. For example, when the value of the first indication information is 1 to 6, the first indication information indicates a unique one of the PRACH subframes; when the value of the first indication information is 11, the first indication information indicates the PRACH resource number. When the value of the first indication information is 12, the first indication information indicates that the PRACH resource number is an odd number of PRACH subframes.

For example, in the ratio 1 of the TDD system, the uplink PRACH subframes are numbered 2, 3, 7, and 8, and the PRACH resource numbers corresponding to the 2, 3, 7, and 8 subframes are respectively 0. 1, 2, and 3; according to the load condition of the PRACH subframe calculated by the eNB, if the load of the PRACH subframe numbered 3 is less than a predetermined threshold, the PRACH mask index may be set to 2, and the number is 3 PRACH subframe (that is, a PRACH resource with a PRACH resource number of 1).

The foregoing predetermined threshold may be set according to the actual situation, which is not limited by the embodiment of the present invention.

The above is only an example of setting the first indication information in the present invention, and the embodiment of the present invention is not limited thereto. The method for setting the first indication information is not limited in the embodiment of the present invention, as long as the first indication information may indicate that the load is less than a predetermined threshold. A PRACH subframe is sufficient.

Step 303: When there is no PRACH subframe with different loads, the eNB sets the second indication information. Specifically, the second indication information is used to indicate that the UE randomly selects a PRACH subframe, and the second indication information may be a PRACH mask index, and the value of the second indication information is different from the value of the first indication information. In this embodiment, the value of the second indication information may be "0".

The above is only an example of setting the second indication information in the present invention. The embodiment of the present invention is not limited thereto. The method for setting the second indication information is not limited in the embodiment of the present invention, as long as the second indication information may indicate the random equal probability selection of the UE. The PRACH subframe can be used. In this embodiment, step 302 and step 303 may be performed alternatively.

Step 304: The eNB sends signaling to the UE, where the signaling carries the first indication information or the second indication information.

In this embodiment, the foregoing signaling may be HO signaling or PDCCH Order signaling.

The foregoing embodiment may implement that the UE sends the preamble index on the PRACH subframe indicated by the first indication information; thereby, the load of the balanced PRACH resource may be balanced, and the capacity of the PRACH is maximized.

FIG. 4 is a flowchart of a method according to still another embodiment of the present invention. As shown in FIG. 4, the method may include:

Step 401: The UE receives HO signaling or PDCCH order (PDCCH Order) signaling sent by the eNB.

Step 402: The UE determines whether the HO signaling or the PDCCH Order signaling carries the first indication information or carries the second indication information. When the H0 signaling or the PDCCH Order signaling carries the first indication information, step 403 is performed; when the H0 signaling or the PDCCH Order signaling carries the second indication information, step 406 is performed.

The second indication information is used to indicate that the UE randomly selects a PRACH subframe, and the second indication information may be a PRACH mask index, and the value of the second indication information is different from the value of the first indication information. In this embodiment, the value of the second indication information may be "0".

Step 403: The UE determines whether the eNB specifies a preamble index for the UE. If the eNB does not specify a preamble index for the UE, step 404 is performed. If the eNB has specified a preamble index for the UE, step 405 is performed. Specifically, in this embodiment, when the foregoing HO signaling or PDCCH Order signaling carries the first indication information, if the HO signaling or the PDCCH Order signaling further carries the third indication information, the UE may determine that the base station does not The UE specifies a preamble index, where the third indication information is used to indicate that the base station does not specify a preamble index for the UE, and the third indication information may be a preamble index, and the value of the third indication information may be "0"; When the HO signaling or the PDCCH Order signaling carries the first indication information, if the HO signaling or the PDCCH Order signaling further carries the fourth indication information, the UE may determine that the base station has specified a preamble index for the UE, and the fourth indication information For indicating that the base station has specified a preamble index for the UE, the fourth indication information may be a preamble index, and the value of the fourth indication information is different from the value of the third indication information. In this embodiment, the fourth indication information is The value can be a positive integer.

Step 404: The UE randomly selects a preamble index of the UE, and sends a preamble index of the UE on the PRACH subframe indicated by the first indication information.

Step 405: The UE sends, on the PRACH subframe indicated by the first indication information, a preamble index specified by the eNB for the UE.

Step 406: The UE determines whether the eNB specifies a preamble index for the UE. If no, step 407 is performed; if the eNB has specified a preamble index for the UE, step 408 is performed.

Specifically, in this embodiment, when the HO signaling or the PDCCH Order signaling carries the second indication information, if the HO signaling or the PDCCH Order signaling further carries the third indication information, the UE may determine that the base station does not The UE specifies a preamble index, where the third indication information is used to indicate that the base station does not specify a preamble index for the UE, and the third indication information may be a preamble index, and the value of the third indication information may be "0"; When the HO signaling or the PDCCH Order signaling carries the second indication information, if the HO signaling or the PDCCH Order signaling further carries the fourth indication information, the UE may determine that the base station has specified a preamble index for the UE, and the fourth indication information And indicating that the base station has specified a preamble index for the UE, where the fourth indication information may be a preamble index, and the value of the fourth indication information is different from the value of the third indication information. In this embodiment, the fourth indication information, The value of 3⁄4 can be a positive integer. Step 407: The UE randomly selects one PRACH subframe in all valid PRACH subframes, and selects one randomly and randomly in the selected PRACH subframe and at least two consecutive PRACH subframes after the selected PRACH subframe. The PRACH subframe transmits the preamble index of the above-mentioned UE random equal probability selection.

Step 408: The UE randomly and equally selects a PRACH subframe in all valid PRACH subframes to send a preamble index designated by the eNB for the UE.

A person skilled in the art can understand that all or part of the steps of implementing the above method embodiments may be completed by using hardware related to program instructions, and the foregoing program may be stored in a computer readable storage medium, and the program is executed when executed. The foregoing steps include the steps of the foregoing method embodiments; and the foregoing storage medium includes: a medium that can store program codes, such as a ROM, a RAM, a magnetic disk, or an optical disk.

FIG. 5 is a schematic diagram of a base station according to an embodiment of the present invention. The base station in this embodiment may implement the process of the embodiment shown in FIG. 1 and FIG. 3 of the present invention. As shown in FIG. 5, the base station may include:

a statistical unit 51, configured to calculate a load of each PRACH subframe;

The sending unit 52 is configured to: when there are at least two PRACH subframes with different loads, send first indication information to the UE, where the first indication information is used to indicate that the load is less than a predetermined threshold, at least one PRACH subframe; or, when not When there are different PRACH subframes, the second indication information is sent to the UE, and the second indication information is used to indicate that the UE randomly selects a PRACH subframe by random equal probability.

In this embodiment, the first indication information may be a PRACH mask index, and the value of the first indication information may be a positive integer. For example, when the value of the first indication information is 1 to 6, the first indication information indicates a unique one of the PRACH subframes. When the value of the first indication information is 11, the first indication information indicates the PRACH resource number. Is an even number of PRACH subframes; When the value of the indication information is 12, the first indication information indicates that the PRACH resource number is an odd number of PRACH subframes. The second indication information may be a PRACH mask index, and the value of the second indication information is different from the value of the first indication information. In this embodiment, the value of the second indication information may be "0".

In this embodiment, the statistical unit 51 may be a component of the processor or the processor that implements the statistical function; the transmitting unit 52 may be a component of the transmitter or the transceiver that implements the transmitting function.

In the foregoing base station, when there are at least two PRACH subframes with different loads, the sending unit 52 sends, to the UE, first indication information for indicating at least one PRACH subframe whose load is less than a predetermined threshold, so that the UE may be in the first indication. The preamble index is sent on the subframe indicated by the information; thus, the load of the balanced PRACH resource can be realized, and the capacity of the PRACH is maximized. Therefore, the load of the balanced PRACH resource can be balanced, and the capacity of the PRACH can be maximized.

FIG. 6 is a schematic diagram of a base station according to another embodiment of the present invention. The base station shown in FIG. 6 may further include:

The selecting unit 53 is configured to: select at least one PRACH subframe whose load is less than a predetermined threshold; and the setting unit 54 is configured to set, according to the PRACH resource number corresponding to the at least one PRACH subframe whose load selected by the selected unit 53 is less than a predetermined threshold. The first indication information.

In this embodiment, the selected unit 53 and the setting unit 54 may be the same component in the processor or different components in the processor that implement the selection and setting functions, respectively.

The base station can balance the load of the PRACH resource and maximize the capacity of the PRACH.

FIG. 7 is a schematic diagram of a user equipment according to an embodiment of the present invention. The user equipment in this embodiment may implement the process of the embodiment shown in FIG. 2 and FIG. 4 of the present invention. As shown in FIG. 7, the user equipment may include:

The receiving unit 71 is configured to receive signaling sent by the base station;

a determining unit 72, configured to determine, when the signaling carries the first indication information or the second indication information, whether the base station specifies a preamble index for the user equipment; The selecting unit 73 is configured to: when the foregoing signaling carries the first indication information, after the determining unit 72 determines that the base station does not specify the preamble index for the user equipment, randomly selects a preamble index of the user equipment; or, when the signaling is When carrying the second indication information, after the determining unit 72 determines that the base station has specified the preamble index for the user equipment, randomly selects one PRACH subframe in the valid PRACH subframe;

The sending unit 74 is configured to: when the foregoing signaling carries the first indication information, send a preamble index of the user equipment selected by the selecting unit 73, in the PRACH subframe specified by the first indication information, where the first indication information is used by And at least one PRACH subframe in which the specified load is less than a predetermined threshold; or, when the signaling carries the second indication information, the PRACH subframe selected by the selecting unit 73 sends a preamble index designated by the base station for the user equipment, where The two indication information is used to indicate that the user equipment randomly selects a PRACH subframe according to a probability.

In this embodiment, the determining unit 72 may: when the signaling carries the first indication information, if the signaling further carries the third indication information, determining that the base station does not specify a preamble index for the user equipment, where the third indication information is used by The indication base station does not specify a preamble index for the user equipment.

The determining unit 72 may be configured to: when the foregoing signaling carries the second indication information, if the signaling further carries the fourth indication information, determining that the base station has specified a preamble index for the user equipment, where the fourth indication information is used to indicate that the base station is the user equipment Specifies the leading index.

In this embodiment, the first indication information may be a PRACH mask index, and the value of the first indication information may be a positive integer. For example, when the value of the first indication information is 1 to 6, the first indication information indicates a unique one of the PRACH subframes. When the value of the first indication information is 11, the first indication information indicates the PRACH resource number. When the value of the first indication information is 12, the first indication information indicates a PRACH subframe whose PRACH resource number is an odd number. The second indication information may be a PRACH mask index, and the value of the second indication information is different from the value of the first indication information. In this embodiment, the value of the second indication information may be "0".

The third indication information may be a preamble index, and the value of the third indication information may be "0"; The fourth indication information may be a preamble index, and the value of the fourth indication information is different from the value of the third indication information. In this embodiment, the value of the fourth indication information may be a positive integer.

In this embodiment, the receiving unit 71 may be a component that implements a receiving function in a receiver or a transceiver; the transmitting unit 74 may be a component that implements a transmitting function in a transmitter or a transceiver; the determining unit 72 and the selecting unit 73 may be a processor. Different components of the determining and selecting functions are implemented in the same component or processor, respectively.

In the user equipment, after the receiving unit 71 receives the signaling sent by the base station, the sending unit 74 may send the preamble index on the PRACH subframe indicated by the first indication information, so that the load of the balanced PRACH resource can be balanced, and the capacity of the PRACH is maximized. Chemical.

A person skilled in the art can understand that the drawings are only a schematic diagram of a preferred embodiment, and the units or processes in the drawings are not necessarily required to implement the invention.

Those skilled in the art can understand that the units in the apparatus in the embodiment can be distributed in the apparatus of the embodiment according to the description of the embodiment, or the corresponding changes can be located in one or more apparatuses different from the embodiment. The units of the above embodiments may be combined into one unit, or may be further split into a plurality of subunits.

It should be noted that the above embodiments are only for explaining the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art that: The technical solutions described in the foregoing embodiments are modified, or some of the technical features are equivalently replaced; and the modifications or substitutions do not deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

Rights request

A method for transmitting, comprising:

The base station calculates the load of each physical random access channel PRACH subframe;

When there is no PRACH subframe with different loads, the base station sends the second indication information to the user equipment, where the second indication information is used to indicate that the user equipment randomly selects a probability.

PRACH subframe.

The method according to claim 1, wherein before the sending, by the base station, the first indication information to the user equipment, the method further includes:

The base station selects at least one PRACH subframe whose load is less than a predetermined threshold, and sets the first indication information according to a PRACH resource number corresponding to the at least one PRACH subframe whose load is less than a predetermined threshold.

The method according to claim 1 or 2, wherein the first indication information and the third indication information are carried in the same signaling, and the third indication information is used to indicate that the base station is not in the same manner The user equipment specifies a leading index.

The method according to any one of claims 1 to 3, wherein the first indication information is a PRACH mask index.

The method according to claim 1, wherein the second indication information and the fourth indication information are carried in the same signaling, and the fourth indication information is used to indicate that the base station is already the user The device specifies a leading index.

The method according to claim 1 or 5, wherein the second indication information is a PRACH mask index, and the value of the second indication information is different from the value of the first indication information. .

7. A method of transmitting, comprising: The user equipment receives signaling sent by the base station;

8. The method of claim 7 wherein:

When the signaling carries the first indication information, if the signaling further carries the third indication information, the user equipment determines that the base station does not specify a preamble index for the user equipment, where the third indication The information is used to indicate that the base station does not specify a preamble index for the user equipment.

The method according to claim 7 or 8, wherein the first indication information is a PRACH mask index.

The method according to claim 7 or 8, wherein the third indication information is a preamble index.

11. The method of claim 7 wherein:

When the signaling carries the second indication information, if the signaling further carries the fourth indication information, the user equipment determines that the base station has specified a preamble index for the user equipment, where the fourth indication information is used. And indicating that the base station has specified a preamble index for the user equipment.

The method according to claim 7 or 11, wherein the second indication information is a PRACH mask index, and the value of the second indication information is the first indication The value of the interest is different.

The method according to claim 7 or 11, wherein the fourth indication information is a preamble index, and the value of the fourth indication information is different from the value of the third indication information.

A base station, comprising:

a statistic unit, configured to collect a load of a PRACH subframe of each physical random access channel, and a sending unit, configured to send, to the user equipment, first indication information, when the at least two PRACH subframes with different loads are present, the first The indication information is used to indicate that the load is less than a predetermined threshold, or the second indication information is sent to the user equipment when the PRACH subframes with different loads are not present, where the second indication information is used to indicate the user The device randomly selects a PRACH subframe with equal probability.

The base station according to claim 14, further comprising:

a selecting unit, configured to: select at least one PRACH subframe whose load is less than a predetermined threshold; and a setting unit, configured to set, according to a PRACH resource number corresponding to the at least one PRACH subframe, where the selected one of the selected units is less than a predetermined threshold The first indication information is described.

16. A user equipment, comprising:

a receiving unit, configured to receive signaling sent by the base station;

a selecting unit, configured to: when the determining unit carries the first indication information, after the determining unit determines that the base station does not specify a preamble index for the user equipment, randomly select a preamble index of the user equipment; or When the signaling carries the second indication information, after the determining unit determines that the base station has specified a preamble index for the user equipment, randomly selects one PRACH subframe in a valid PRACH subframe;

a sending unit, configured to: when the signaling carries the first indication information, in the first indication a preamble index of the user equipment, where the first indication information is used to specify at least one PRACH subframe whose load is less than a predetermined threshold; or, when the signaling carries the second indication information, the PRACH selected by using the selection unit The subframe sends a preamble index that is specified by the base station to the user equipment, where the second indication information is used to indicate that the user equipment randomly selects a PRACH subframe.

17. The user equipment according to claim 16, wherein

The determining unit is specifically configured to: when the signaling carries the first indication information, if the signaling further carries the third indication information, determining that the base station does not specify a preamble index for the user equipment, where The third indication information is used to indicate that the base station does not specify a preamble index for the user equipment.

18. The user equipment of claim 16, wherein

The determining unit is specifically configured to: when the signaling carries the second indication information, if the signaling further carries the fourth indication information, determining that the base station has specified a preamble index for the user equipment, where The fourth indication information is used to indicate that the base station has specified a preamble index for the user equipment.