WO2018028574A1

WO2018028574A1 - Random access method and apparatus in wireless communication system

Info

Publication number: WO2018028574A1
Application number: PCT/CN2017/096461
Authority: WO
Inventors: 许靖
Original assignee: 中兴通讯股份有限公司
Priority date: 2016-08-12
Filing date: 2017-08-08
Publication date: 2018-02-15
Also published as: CN107734601A

Abstract

Provided are a random access method and apparatus in a wireless communication system. The method comprises: receiving indication information from a base station, and initiating random access under a first coverage level indicated by the indication information; when it is determined that the number of times that the random access initiated under the first coverage level fails reaches a threshold for the number of random access times corresponding to the first coverage level, randomly selecting a first access resource from competitive access resources corresponding to a second coverage level, wherein the second coverage level is higher than the first coverage level; and initiating random access under the second coverage level by utilising the randomly selected first access resource. By means of the embodiments in the present invention, the problem of high coverage level random access failure when a coverage level needs to be improved because a terminal has failed to initiate random access on a PRACH resource designated by a base station a plurality of times is solved, thus achieving the effect of increasing the success rate of the base station initiating random access.

Description

Random access method and device in wireless communication system

Technical field

The present invention relates to the field of communications, and in particular to a random access method and apparatus in a wireless communication system.

Background technique

The enhanced MTC (Machine Type Communication (eMTC) and the Narrow Band Internet of Things (NB-IoT) technology support the Evolved Node B (eNodeB). The random access process, for example, the eNodeB instructs the UE to initiate a random access procedure by sending a downlink physical control channel (Physical Downlink Control Channel, PDCCH) order. In this case, the eNodeB indicates the user equipment (User Equipment, UE for short). The Packet Random Access CHannel (referred to as PRACH) resource information (the PRACH information indicated by the PDCCH order is shown in Table 1.) After the UE receives the instruction of the eNodeB, the PRACH is sent on the resource specified by the eNodeB. Specifically, corresponding to the eMTC system, the UE sends the PRACH by using the Preamble codeword specified by the eNodeB. Table 1 is the PRACH information indicated by the PDCCH order, as shown in Table 1:

Table 1

In the eMTC and NB-IoT systems, the PRACH resources are configured according to the coverage level, and each coverage level corresponds to a set of PRACH time-frequency resources, and the eMTC system also configures a set of preamble codewords for each coverage. After the UE initiates a random access failure on the PRACH resource of the current coverage level, the random access may be initiated again on the PRACH resource of the current coverage level. When the random access number initiated by the UE on the current coverage level PRACH resource reaches the random access number threshold of the coverage level but does not reach the maximum number of times threshold, the random access may be initiated on the PRACH resource corresponding to the next higher coverage level. .

For the random access procedure initiated by the eNodeB, the PRACH resource index/subcarrier ID or the preamble codeword indicated by the eNodeB must be in the PRACH resource group of the initial coverage level, and ensure that the UE initiates random connection according to the PRACH resource indicated by the eNodeB on the initial coverage level. Into the process. However, when the UE initiates a random access failure on the PRACH resource specified by the eNodeB and needs to improve the coverage level, the PRACH resource index/subcarrier ID or the preamble codeword indicated by the eNodeB may not exist in the higher level PRACH resource group. At this time, the UE may not initiate random access, or send the PRACH according to the PRACH information indicated in the eNodeB, but the eNodeB will not respond. As a result, the random access fails, and the success rate of the random access initiated by the eNodeB is reduced.

In view of the above problems, an effective solution has not been proposed in the related art.

Summary of the invention

The embodiment of the present invention provides a random access method and apparatus in a wireless communication system, to at least solve the problem that the terminal needs to improve the coverage level when the terminal randomly initiates a random access failure on the PRACH resource specified by the base station in the related art. The problem of random access failure.

According to an embodiment of the present invention, a random access party in a wireless communication system is provided The method includes: receiving indication information from a base station, and initiating random access at a first coverage level indicated by the indication information; determining that a number of random access failures initiated under the first coverage level reaches a location When the random access threshold corresponding to the first coverage level is used, the first access resource is randomly selected in the contention access resource corresponding to the second coverage level, where the second coverage level is higher than the first coverage Level; initiating random access at the second coverage level using the randomly selected first access resource.

Optionally, the initiating the random access in the first coverage level indicated by the indication information includes: determining whether the second access resource indicated by the indication information is a non-competition access resource; In the case of the first operation, when the random access is initiated in the first coverage level, the second access resource indicated by the indication information initiates random access in the first coverage level. And, when the random access is initiated in the first coverage level after the initial time, the third access resource is randomly selected in the contention access resource corresponding to the first coverage level, and the third access is utilized. The inbound resource initiates random access in the first coverage level; when the random access is initiated in the first coverage level after the initial or initial time, the second access resource indicated according to the indication information is in the In the case of the first coverage level, the random access is continuously initiated; if the determination result is no, when the random access is initiated under the first coverage level after the initial or initial time, the first coverage is Competitive access resource level corresponding to the fourth access resource is randomly selected, and using the fourth resource access on the first lower level she initiates a random access cover.

Optionally, the access resource includes a physical random access channel PRACH resource and/or a preamble Preamble code.

Optionally, the non-contention access resource is determined by determining, by using at least one of the following manners, determining, by using a system broadcast, the non-contention access resource, determining that the remaining resources after removing the specific resource in the contention access resource is the non-competition Access resources.

In another embodiment of the present invention, a random access method in a wireless communication system is provided, including: determining that a terminal needs to initiate random access at a second coverage level; corresponding to the second coverage level Receiving access resources included in the contention access resource from the terminal Random access request.

Optionally, before determining that the terminal needs to initiate random access in the second coverage level, the method further includes: sending indication information to the terminal, where the indication information is used to indicate the terminal Initiating random access at a first coverage level; receiving a random access request initiated by the terminal at the first coverage level; determining that the terminal needs to initiate random access at the second coverage level, including: determining The number of random access failures initiated by the terminal at the first coverage level reaches a random access threshold corresponding to the first coverage level.

Optionally, receiving the random access request initiated by the terminal at the first coverage level includes: receiving, by the terminal, the second access resource indicated by the indication information, starting at the first coverage level. Or a random access request; or receiving a random access request from the terminal on an access resource included in a contention access resource corresponding to the first coverage level.

In another embodiment of the present invention, a random access apparatus in a wireless communication system is provided, including: a first initiating module configured to receive indication information from a base station, and instructed by the indication information a random access is initiated in a coverage level, and the selecting module is configured to: when it is determined that the number of random access failures initiated under the first coverage level reaches a random access threshold corresponding to the first coverage level, The first access resource is randomly selected from the contention access resources corresponding to the two coverage levels, wherein the second coverage level is higher than the first coverage level; and the second initiating module is configured to use the randomly selected An access resource initiates random access at the second coverage level.

Optionally, when the random access is initiated in the first coverage level indicated by the indication information, the first initiating module includes: a determining unit, configured to determine a second connection indicated by the indication information Whether the incoming resource is a non-competitive access resource; the first initiating unit is configured to perform one of the following operations when the determining result of the determining unit is yes: when the first random access is initiated in the first coverage level And the second access resource indicated by the indication information initiates random access at the first coverage level, and when the random access is initiated at the first coverage level after the initial time, Selecting a third access resource randomly among the contention access resources corresponding to the coverage level, and using the third access resource to initiate the first coverage level Random access; when the first access level is initiated, the second access resource, according to the indication information, continues to initiate random access at the first coverage level. a second initiating unit, configured to: when the determining result of the determining unit is negative, when the random access is initiated under the first coverage level after the initial or initial time, corresponding to the first coverage level The fourth access resource is randomly selected from the contention access resources, and the fourth access resource is used to initiate random access at the first coverage level.

In another embodiment of the present invention, a random access apparatus in a wireless communication system is provided, including: a determining module, configured to determine that a terminal needs to initiate random access at a second coverage level; and a first receiving module, And configuring to receive a random access request from the terminal on an access resource included in a contention access resource corresponding to the second coverage level.

Optionally, the device further includes: a sending module, configured to send indication information to the terminal before determining that the terminal needs to initiate random access in the second coverage level, where the indication information is used by Instructing the terminal to initiate random access at a first coverage level; the second receiving module is configured to receive a random access request initiated by the terminal at the first coverage level; the determining module includes: determining a unit And determining, by the terminal, that the number of random access failures initiated by the terminal at the first coverage level reaches a random access threshold corresponding to the first coverage level.

According to still another embodiment of the present invention, a storage medium is also provided. The storage medium is arranged to store program code for performing the above steps.

According to still another embodiment of the present invention, there is also provided a processor for running a program, wherein the program is executed to perform the method of any of the above.

The embodiment of the present invention receives the indication information from the base station, and initiates random access according to the indication information at the first coverage level; when it is determined that the number of random access failures initiated under the first coverage level reaches the first When the threshold of the number of random accesses corresponding to the level of coverage is exceeded, the first access resource is randomly selected in the resource pool corresponding to the second coverage level, and the random access is initiated by using the randomly selected first access resource in the second coverage level. It can solve the problem that the terminal needs to improve the coverage level when the random access failure is initiated multiple times on the PRACH resource specified by the base station, and the coverage is high. The problem of random access failure of the level achieves the effect of improving the success rate of the random access initiated by the base station.

DRAWINGS

The drawings described herein are intended to provide a further understanding of the invention, and are intended to be a part of the invention. In the drawing:

1 is a block diagram showing the hardware structure of a mobile terminal of a random access method in a wireless communication system according to an embodiment of the present invention;

2 is a flow chart (1) of a method according to an embodiment of the present invention;

3 is a flowchart (2) of a method according to an embodiment of the present invention;

4 is a structural block diagram (1) of a random access apparatus in a wireless communication system according to an embodiment of the present invention;

FIG. 5 is a structural block diagram (1) of a first initiating module 42 of a random access device in a wireless communication system according to an embodiment of the present invention;

6 is a structural block diagram (2) of a random access device in a wireless communication system according to an embodiment of the present invention;

7 is a block diagram showing a preferred structure of a random access device in a wireless communication system according to an embodiment of the present invention.

detailed description

The invention will be described in detail below with reference to the drawings in conjunction with the embodiments. It should be noted that the embodiments in the present application and the features in the embodiments may be combined with each other without conflict.

It is to be understood that the terms "first", "second" and the like in the specification and claims of the present invention are used to distinguish similar objects, and are not necessarily used to describe a particular order or order.

The method embodiments provided by the embodiments of the present application may be implemented in a mobile terminal, a computer terminal, or the like. Taking the operation on the mobile terminal as an example, FIG. 1 is an embodiment of the present invention. A hardware block diagram of a mobile terminal of a random access method. As shown in FIG. 1, mobile terminal 10 may include one or more (only one shown in FIG. 1) processor 102 (processor 102 may include, but is not limited to, a processing device such as a microprocessor MCU or a programmable logic device FPGA. ), a memory 104 configured to store data, and a transmission device 106 configured as a communication function. It will be understood by those skilled in the art that the structure shown in FIG. 1 is merely illustrative and does not limit the structure of the above electronic device. For example, the mobile terminal 10 may also include more or fewer components than those shown in FIG. 1, or have a different configuration than that shown in FIG.

The memory 104 can be configured as a software program and a module for storing application software, such as a program instruction/module corresponding to the random access method in the embodiment of the present invention, and the processor 102 executes by executing a software program and a module stored in the memory 104. Various functional applications and data processing, that is, the above methods are implemented. Memory 104 may include high speed random access memory, and may also include non-volatile memory such as one or more magnetic storage devices, flash memory, or other non-volatile solid state memory. In some examples, memory 104 may further include memory remotely located relative to processor 102, which may be connected to mobile terminal 10 over a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

Transmission device 106 is arranged to receive or transmit data via a network. The above-described network specific example may include a wireless network provided by a communication provider of the mobile terminal 10. In one example, the transmission device 106 includes a Network Interface Controller (NIC) that can be connected to other network devices through a base station to communicate with the Internet. In one example, the transmission device 106 can be a Radio Frequency (RF) module configured to communicate with the Internet wirelessly.

In this embodiment, a random access method in a wireless communication system is provided. FIG. 2 is a flowchart (1) of a method according to an embodiment of the present invention. As shown in FIG. 2, the process includes the following steps:

Step S202: Receive indication information from the base station, and initiate random access according to the first coverage level indicated by the indication information.

Step S204, when it is determined that the random access failure initiated under the first coverage level is When the number of random access times corresponding to the first coverage level is reached, the first access resource is randomly selected in the contention access corresponding to the second coverage level, where the second coverage level is higher than the first coverage level. ;

Step S206, initiating random access under the second coverage level by using the randomly selected first access resource.

The second coverage level may be one level higher than the first coverage level, or may be two, three or more levels higher. In the embodiment of the present invention, the contention access resources corresponding to the coverage levels may be respectively formed into a resource pool, and the non-competition access resources corresponding to the coverage levels may respectively form a resource pool, and the same coverage level corresponds to the competition. The resource pool composed of the inbound resources and the resource pool composed of the non-competitive access resources may be relatively independent, and the two resource pools may have overlapping portions or may not overlap at all.

The above-mentioned steps solve the problem that the random access failure of the high coverage level fails when the terminal initiates the random access failure on the PRACH resource specified by the base station multiple times, and the success rate of the random access initiated by the base station is improved.

Optionally, the execution body of the foregoing steps may be a terminal or the like, but is not limited thereto.

In an optional embodiment, the initiating the random access in the first coverage level indicated by the foregoing indication information may include: determining whether the second access resource indicated by the indication information is a non-competitive access resource; If the result is YES, one of the following operations is performed: when the random access is initiated in the first coverage level, the second access resource indicated by the indication information initiates random access at the first coverage level. And, when the random access is initiated in the foregoing first coverage level after the initial time, the third access resource is randomly selected in the contention access resource corresponding to the first coverage level, and the third access resource is used in the foregoing The random access is initiated in the first coverage level; when the random access is initiated in the first coverage level after the initial or initial time, the second access resource indicated by the indication information continues to initiate random access in the first coverage level; In the case that the determination result is no, when the random access is initiated under the first coverage level after the initial or initial time, the first Level corresponding to the lid contention access resource is randomly selected access resource fourth, and using the fourth resource access initiated at the first level of coverage Random access. In this embodiment, in the first coverage level, the randomly selected third access resources may be the same or different when multiple random accesses are initiated after the initial time. Similarly, when multiple random accesses are initiated after the initial or initial time, the randomly selected fourth access resources may be the same or different.

In an optional embodiment, the access resource includes a physical random access channel PRACH resource and/or a preamble Preamble code.

In an optional embodiment, the non-contention access resource may be determined by determining, by using at least one of the following manners, determining, by using a system broadcast, the non-contention access resource, and determining that the remaining resource after removing the specific resource in the contention access resource is The above non-competitive access resources. It should be noted that, when determining non-contention access resources corresponding to other coverage levels, the foregoing manner may also be used for determining.

In this embodiment, a random access method in a wireless communication system is provided. FIG. 3 is a flowchart (2) of a method according to an embodiment of the present invention. As shown in FIG. 3, the process includes the following steps:

Step S302, determining that the terminal needs to initiate random access under the second coverage level;

Step S304: Receive a random access request from the terminal on an access resource included in the contention access resource corresponding to the second coverage level.

The foregoing steps solve the problem that the PRACH resource specified by the base station in the high coverage level fails the random access of the terminal, and improves the success rate of the base station initiating the random access.

Optionally, the execution body of the foregoing steps may be a base station, but is not limited thereto.

In an optional embodiment, before determining that the terminal needs to initiate random access in the second coverage level, the method may further include: sending the indication information to the terminal, where the indication information is used to indicate the terminal. Initiating random access at a first coverage level; receiving a random access request initiated by the terminal at the first coverage level; determining that the terminal needs to initiate random access at the second coverage level includes: determining that the terminal is in the foregoing The number of random access failures initiated by the first coverage level reaches the random access threshold corresponding to the first coverage level.

In an optional embodiment, receiving the terminal initiated by the terminal at the first coverage level The random access request may include: receiving, by the terminal, a random access request initiated by using the second access resource indicated by the foregoing indication information, in the first coverage level; or, in a contention access corresponding to the first coverage level. A random access request from the above terminal is received on an access resource included in the resource.

The present invention will be described below in conjunction with specific embodiments:

Embodiment 1 includes the following steps:

Step 1: The eNodeB instructs the UE to initiate a random access procedure (for example, the eNodeB sends a PDCCH order to indicate that the UE initiates a random access procedure), and indicates the PRACH resource information used by the UE.

Step 2: After receiving the indication of the eNodeB, the UE acquires its corresponding non-contention PRACH resource and/or preamble codeword, contention PRACH resource and/or preamble codeword according to the coverage level indicated by the eNodeB.

The non-contention PRACH resource and/or the preamble codeword, the competing contention PRACH resource, and/or the preamble codeword corresponding to the coverage level are configured by the system, and the two groups of resources may overlap or may not overlap at all.

Step 3: If the non-contention PRACH resource and/or the preamble codeword according to the eNodeB indication information and the initial coverage level can determine the PRACH resource or the preamble codeword to be used by the UE, the UE initiates the randomization using the determined PRACH resource or the preamble codeword. Access.

Step 3.1: If the UE initiates the random access failure in step 3, the PRACH resource is randomly selected from the contention PRACH time-frequency resources of the current coverage level to transmit the related information according to the contention random access mode in 36.321. For the eMTC system, the UE randomly selects a preamble code within the contention preamble codeword group of the current coverage level, and initiates random access again.

Step 3.1 has two options:

Solution 1: After the UE initiates random access failure in step 3, the initial indication indicated by the eNodeB In the coverage, the PRACH resource and the Preamble codeword are randomly selected in the contention resources in a competitive manner to initiate random access again.

If the random access number initiated by the UE on the initial coverage level PRACH resource indicated by the eNodeB reaches the random access number threshold of the coverage level but does not reach the total coverage threshold, the PRACH resource of the high coverage level is followed. The competition mode randomly selects the PRACH resource and the Preamble codeword in the contention resource to initiate random access again.

Scenario 2: After the random access failure is initiated in step 3, the number of random access initiated by the UE on the initial coverage level PRACH resource indicated by the eNodeB is less than the random access threshold of the coverage level and less than the total coverage threshold. Then, according to step 3, the random access is initiated again by using the indication resource. If the random access number initiated by the UE on the initial coverage level PRACH resource indicated by the eNodeB reaches the random access number threshold of the coverage level but does not reach the total coverage threshold, the PRACH resource of the high coverage level is followed. The competition mode randomly selects a PRACH resource or a preamble codeword in a contention resource to initiate random access.

Step 4: If the non-contention PRACH resource and/or preamble codeword according to the eNodeB indication information and the initial coverage level cannot determine the PRACH resource or preamble codeword to be used by the UE, the contention PRACH resource and/or preamble at the initial coverage level The codeword randomly selects a PRACH resource or a preamble codeword in a contention manner to initiate random access.

Step 4.1: If the random access fails in the step 4 of the UE, if the random access number initiated on the initial coverage level PRACH resource indicated by the eNodeB is less than the random access threshold of the coverage level and less than the total coverage threshold, then The random access is initiated by randomly selecting the PRACH resource or the preamble codeword in a contention manner in the contention PRACH resource and/or the preamble codeword of the initial coverage level. Step 4.2: If the random access number initiated by the UE on the initial coverage level PRACH resource indicated by the eNodeB reaches the random access number threshold of the coverage level but does not reach the total coverage threshold, the competitive PRACH in the high coverage level On the resource, random access is initiated by randomly selecting a PRACH resource or a preamble codeword according to a competitive manner.

Specific embodiment 2:

This embodiment includes the following steps:

Step 1. The eMTC FDD system is configured with four coverage levels, namely CEL0/CEL1/CEL2/CEL2, of which CEL0 has the lowest coverage level. The PRACH resource information of the four coverage levels is shown in Table 2 (where all resources are both competing access resources and non-competitive access resources).

Table 2

According to the 36.211 protocol, the PRACH time domain resources (radio frame number and subframe number) corresponding to the foregoing PRACH configuration index are as shown in Table 3:

table 3

Step 2: In the eMTC system, the eNodeB sends a PDCCH order, where the indicated PRACH information is as shown in Table 4.

Table 4

Step 3: The UE receives the PDCCH order, obtains an initial coverage level of CEL1, and obtains a PRACH resource corresponding to the CEL1:

(1) The PRACH configuration index is 9, that is, the Preamble code is transmitted on the subframes 1, 4, and 7 of each radio frame, and the PRACH resource number Nprach is 3 in this configuration;

(2) The PRACH starting subframe period is 4 subframes;

(3) PRACH frequency domain starting PRB is PRB=0;

(4) The number of Preamble codes is 12, and the range is 12-23;

(5) The number of random access initiated on CEL1 is min(3,20)=3 times.

Step 4. According to the 36.321 and 36.211 standard protocols, the PRACH indicated by the PDCCH order Mask Index=3, within the non-contention PRACH resource of CEL1, it is determined that the UE transmits the Preamble code on subframe 7 of each radio frame.

Step 5: According to the PRACH starting subframe period, the subframe is 4 subframes, and the UE is satisfied.

The Preamble code is sent on the subframe. Here, sf is the radio frame number and ns is the slot number.

Step 6. The codeword 15 indicated by the Preamble Index in the PDCCH order is in the non-contention preamble codeword of the CEL1, and the UE uses 15 as its Preamble code.

Step 7: The UE sends the Preamble codeword 15 on the subframe determined in step 5 and the PRACH resource with PRB=0.

Step 8: If the random access procedure initiated in step 7 fails, and the number of random access initiated on CEL0 is less than 3, then it is satisfied.

The Preamble codeword 15 is transmitted again on the subframe and the PRACH resource with PRB=0.

Step 9: If the number of random accesses initiated on the CEL1 reaches 3 times (the total number of times the threshold has not been reached 20 times), the UE raises the coverage level to CEL2, and obtains the PRACH resource corresponding to the level:

(1) The PRACH configuration index is 6, that is, the Preamble code is sent on the subframes 1, 6 of each radio frame;

(2) The PRACH starting subframe period is 8 subframes;

(3) PRACH frequency domain starting PRB is PRB=0;

(4) The number of Preamble codes is 12, and the range is 24-35;

(5) The number of random access initiated on CEL2 is min(3,20-3)=3 times.

Step 10: The UE randomly selects a subframe on subframes 1 and 6, and randomly selects a codeword in the preamble codeword [24, 35], and transmits the preamble code on PRB=0.

In step 11, the steps 9-10 are repeated until the random access is successful, or the total number of random accesses initiated in all the coverages reaches the maximum number of repetitions min(3+3+3, 20)=9.

Specific embodiment 3

This embodiment includes the following steps:

Step 1. The NB-IoT system is configured with three coverage levels, namely CEL0/CEL1/CEL2, of which CEL0 has the lowest coverage level. The three coverage levels of PRACH resource information are shown in Table 5 (where all resources are both contention access resources and non-competition access resources).

table 5

Step 2: The eNodeB sends a PDCCH order, where the indicated PRACH information is as shown in Table 6.

Table 6

Step 3: The UE receives the PDCCH order, obtains an initial coverage level of CEL0, and obtains The PRACH resource corresponding to CEL0 has a period of 640 ms, a starting subframe offset of 8, a subcarrier number of 12, a range of 0-11, and the number of random access initiated on CEL0 is min(3,20)=3. Times.

Step 4: The eNodeB indicates that the subcarrier ID used by the UE to send the PRACH signal is 6, which is within the non-competitive subcarrier range of CEL0, and the UE initiates random access by using the indication resource.

Step 5, the UE is satisfied

The subframe is used as the starting subframe to transmit the PRACH signal, and the used subcarrier ID is 6. Here, sf is the radio frame number and ns is the slot number.

Step 6, if the random access procedure initiated in step 5 fails, and the number of random access initiated on CEL0 is less than 3, then one subcarrier is randomly selected in [0, 11], and is satisfied.

The PRACH signal is transmitted again at the subframe.

Step 7: If the number of random accesses initiated on the CEL0 reaches 3 times (the total number of times has not been reached 20 times), the UE raises the coverage level to CEL1, and obtains the PRACH resource corresponding to the level, and the period is 640 ms. The initial subframe offset is 64, the number of subcarriers is 12, the range is 12-23, and the number of random access initiated on CEL1 is min(3, 20-3)=3 times.

In step 8, the UE randomly selects one subcarrier in [12, 23], and starts to transmit the PRACH signal again at the subframe (sf+ns2mod 640=64).

Step 9. Repeat steps 7-8 until the random access is successful, or the total number of random accesses initiated in all coverages reaches the maximum number of repetitions min(3+3+3,20)=9.

Through the description of the above embodiments, those skilled in the art can clearly understand that the method according to the above embodiment can be implemented by means of software plus a necessary general hardware platform, and of course, by hardware, but in many cases, the former is A better implementation. Based on such understanding, the technical solution of the present invention, which is essential or contributes to the prior art, may be embodied in the form of a software product stored in a storage medium (such as ROM/RAM, disk, The optical disc includes a number of instructions for causing a terminal device (which may be a cell phone, a computer, a server, or a network device, etc.) to perform the methods described in various embodiments of the present invention.

Specific Embodiment 4: The following steps are included:

Step 1. The NB-IoT system is configured with three coverage levels, namely CEL0/CEL1/CEL2, of which CEL0 has the lowest coverage level. The three coverage level PRACH resource information is shown in Table 5 (where PRACH subcarriers 0-35 are subcarriers used for contention access, where 0 is a specific carrier, and therefore 1-35 is a non-competitive subcarrier).

table 5

Table 6

Step 3: The UE receives the PDCCH order, obtains the initial coverage level as CEL0, and obtains the PRACH resource corresponding to CEL0, the period is 640 ms, the starting subframe offset is 8, the number of subcarriers is 24, and the non-competitive subcarrier is 1-23, the competing subcarrier is 0-23, and the number of random access initiated on CEL0 is min(3,20)=3 times.

Step 4: The eNodeB indicates that the subcarrier ID used by the UE to transmit the PRACH signal is 0, which is not in the non-competitive subcarrier range of CEL0, and the UE randomly selects one subcarrier on the competing subcarrier [0-23], and satisfies

The subframe transmits the PRACH signal as the starting subframe. Here, sf is the radio frame number and ns is the slot number.

Step 5: If the random access procedure initiated in step 5 fails, and the number of random access initiated on CEL0 is less than 3, then one subcarrier is randomly selected on the competing subcarrier [0-23], and is satisfied.

The PRACH signal is transmitted again at the subframe.

Step 6: If the number of random accesses initiated on the current coverage level CEL0 reaches 3 times (the total number of times has not been reached 20 times), the UE raises the coverage level to CEL1, and obtains the PRACH resource corresponding to the level, and the period is 640ms, the starting subframe offset is 64, the number of subcarriers is 12, the range is 12-23, and the number of random access initiated on CEL1 is min(3,20-3)=3 times.

Step 7, the UE randomly selects one subcarrier in the competing subcarrier [24, 35] of CEL1, and satisfies

The PRACH signal is transmitted at the subframe.

Step 8. If the random access procedure initiated in step 7 fails, step 6-7 is repeated until the random access is successful, and the maximum number of repetitions min(3+3+3, 20)=9 is reached.

In this embodiment, a random access device is also provided, which is used to implement the foregoing embodiments and preferred embodiments, and is not described again. As used below, the term "module" may implement a combination of software and/or hardware of a predetermined function. Although the apparatus described in the following embodiments is preferably implemented in software, hardware, or a combination of software and hardware, is also possible and contemplated.

4 is a structural block of a random access device in a wireless communication system according to an embodiment of the present invention; Figure (a), as shown in Figure 4, the device includes: a first initiating module 42, a selection module 44 and a second initiating module 46, the device is described below:

The first initiating module 42 is configured to receive the indication information from the base station, and initiate a random access under the first coverage level indicated by the indication information; the selecting module 44 is connected to the first initiating module 42 and configured to determine When the number of random access failures initiated by the first coverage level reaches the threshold of the random access times corresponding to the first coverage level, the first access resource is randomly selected in the contention access resources corresponding to the second coverage level. The second coverage level is higher than the first coverage level; the second initiating module 46 is connected to the selection module 44, and is configured to initiate randomization at the second coverage level by using the randomly selected first access resource. Access.

In an optional embodiment, FIG. 5 is a structural block diagram (1) of a first initiating module 42 of a random access device in a wireless communication system according to an embodiment of the present invention, as shown in FIG. The first initiating module 42 may be configured to: determine, by the determining unit 52, whether the second access resource indicated by the indication information is a non-contention access resource, when the random access is initiated by the first coverage level indicated by the information; The first initiating unit 54 is configured to perform one of the following operations when the determination result of the determining unit 52 is YES: when the random access is initiated for the first time in the first coverage level, the first indication according to the indication information And the second access resource initiates the random access in the foregoing first coverage level, and randomly selects the contention access resources corresponding to the first coverage level when the random access is initiated in the first coverage level after the initial time. Third accessing the resource, and using the foregoing third access resource to initiate random access at the first coverage level; when the first or the first time is after the first coverage When the random access is initiated, the second access resource indicated by the foregoing indication information continues to initiate random access in the first coverage level; the second initiating unit 56 is configured to determine that the determination result in the determining unit 52 is If the random access is initiated in the foregoing first coverage level after the initial or initial time, the fourth access resource is randomly selected in the contention access resource corresponding to the first coverage level, and the fourth access resource is used. The access resource initiates random access under the first coverage level.

In an optional embodiment, the foregoing apparatus further includes a resource determining module, configured to determine, by using at least one of the following manners, a non-contention access resource: determining, by using a system broadcast, the non-contention access resource, determining that the contention is in the contention access resource The remaining resources after removing a specific resource are the above non-contention access resources. It should be noted that, when determining non-contention access resources corresponding to other coverage levels, the foregoing manner may also be used for determining.

6 is a structural block diagram (2) of a random access device in a wireless communication system according to an embodiment of the present invention. As shown in FIG. 6, the device includes: a determining module 62 and a first receiving module 64, and the device is Be explained:

The determining module 62 is configured to determine that the terminal needs to initiate random access in the second coverage level. The first receiving module 64 is connected to the determining module 62, and is configured to be included in the contention access resource corresponding to the second coverage level. The access resource receives a random access request from the terminal.

In an alternative embodiment, FIG. 7 is a block diagram showing a preferred structure of a random access device in a wireless communication system according to an embodiment of the present invention. As shown in FIG. 7, the device includes the module shown in FIG. The sending module 72 is further configured to: before the determining that the terminal needs to initiate random access in the second coverage level, send the indication information to the terminal, where the indication information is used to indicate that the terminal is at the first coverage level. The second receiving module 74 is connected to the sending module 72, and is connected to the determining module 62, and configured to receive the random access request initiated by the terminal at the first coverage level; the determining module 62 The determining unit is configured to determine that the number of random access failures initiated by the terminal at the first coverage level reaches a random access threshold corresponding to the first coverage level.

In an optional embodiment, the random access request initiated by the terminal at the first coverage level is received by: receiving, by the terminal, the second access resource indicated by the indication information, at the first coverage level. And a random access request initiated by the terminal; or receiving, by the access resource included in the resource pool corresponding to the first coverage level, a random access request from the terminal.

It should be noted that each of the above modules can be implemented by software or hardware. The latter can be implemented in the following manner, but is not limited thereto: the above modules are all located in the same processor; or, the above modules are respectively located in different processors in any combination.

Embodiments of the present invention also provide a storage medium. Optionally, in the embodiment, the above storage medium may be configured to store program code for performing the above steps.

Optionally, in the embodiment, the foregoing storage medium may include, but is not limited to, a USB flash drive, a Read-Only Memory (ROM), and a Random Access Memory (RAM). A variety of media that can store program code, such as a hard disk, a disk, or an optical disk.

Optionally, in this embodiment, the processor performs the above steps according to the stored program code in the storage medium.

For example, the specific examples in this embodiment may refer to the examples described in the foregoing embodiments and the optional embodiments, and details are not described herein again.

It will be apparent to those skilled in the art that the various modules or steps of the above-described embodiments of the present invention can be implemented by a general-purpose computing device, which can be centralized on a single computing device or distributed among multiple computing devices. Optionally, they may be implemented by program code executable by the computing device such that they may be stored in the storage device by the computing device and, in some cases, may be different from this The steps shown or described are performed sequentially, or they are separately fabricated into individual integrated circuit modules, or a plurality of modules or steps thereof are fabricated into a single integrated circuit module. Thus, embodiments of the invention are not limited to any specific combination of hardware and software.

The above description is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Industrial applicability

As described above, a random access method in a wireless communication system provided by an embodiment of the present invention And the device has the following beneficial effects: the problem that the random access failure of the high coverage level fails when the terminal initiates the random access failure on the PRACH resource specified by the base station multiple times, and the success rate of the random access initiated by the base station is improved. Effect.

Claims

A random access method in a wireless communication system, comprising:

Receiving indication information from the base station, and initiating random access under the first coverage level indicated by the indication information;

When it is determined that the number of times of the random access failure initiated by the first coverage level reaches the random access number threshold corresponding to the first coverage level, the content of the contention access resource corresponding to the second coverage level is randomly selected. An access resource, wherein the second coverage level is higher than the first coverage level;

Random access is initiated at the second coverage level using the randomly selected first access resource.
The method of claim 1, wherein initiating random access at the first coverage level indicated by the indication information comprises:

Determining whether the second access resource indicated by the indication information is a non-contention access resource;

If the result of the determination is yes, one of the following operations is performed: when the random access is initiated under the first coverage level for the first time, the second access resource indicated according to the indication information is at the first coverage level. The third access resource is randomly selected and used in the contention access resource corresponding to the first coverage level when the random access is initiated in the first coverage level after the initial time. The third access resource initiates random access at the first coverage level; when the random access is initiated under the first coverage level after the initial or initial time, the second indication according to the indication information The access resource continuously initiates random access under the first coverage level;

If the result of the determination is negative, when the random access is initiated in the first coverage level after the initial or initial time, the fourth access resource is randomly selected in the contention access resources corresponding to the first coverage level. And using the fourth access resource to initiate random access at the first coverage level.
The method of claim 1 or 2, wherein the access resources comprise physical random access channel PRACH resources and/or preamble Preamble codes.
The method of claim 2, wherein the non-contention access resource is determined by at least one of:

Determining the non-contention access resource by using a system broadcast, and determining that the remaining resource after removing the specific resource in the contention access resource is the non-contention access resource.
A random access method in a wireless communication system, comprising:

Determining that the terminal needs to initiate random access under the second coverage level;

Receiving a random access request from the terminal on an access resource included in a contention access resource corresponding to the second coverage level.
The method of claim 4, wherein

Before the determining that the terminal needs to initiate the random access in the second coverage level, the method further includes: sending the indication information to the terminal, where the indication information is used to indicate that the terminal is at the first coverage level. Initiating a random access; receiving a random access request initiated by the terminal under the first coverage level;

Determining that the terminal needs to initiate random access in the second coverage level comprises: determining that the number of random access failures initiated by the terminal in the first coverage level reaches a random connection corresponding to the first coverage level The number of entry thresholds.
The method of claim 6, wherein receiving the random access request initiated by the terminal under the first coverage level comprises:

Receiving, by the terminal, a random access request initiated by the second access resource indicated in the indication information at the first coverage level; or

Receiving a random access request from the terminal on an access resource included in a contention access resource corresponding to the first coverage level.
A random access device in a wireless communication system, comprising:

a first initiating module, configured to receive indication information from a base station, and initiate random access at a first coverage level indicated by the indication information;

a selection module, configured to: when it is determined that the number of random access failures initiated by the first coverage level reaches a random access number threshold corresponding to the first coverage level, the contention access resource corresponding to the second coverage level Selecting a first access resource randomly, wherein the second coverage level is higher than the first coverage level;

The second initiating module is configured to initiate random access at the second coverage level by using the randomly selected first access resource.
The apparatus according to claim 8, wherein when the random access is initiated under the first coverage level indicated by the indication information, the first initiating module comprises:

a determining unit, configured to determine whether the second access resource indicated by the indication information is a non-contention access resource;

a first initiating unit, configured to: when the determining result of the determining unit is yes, performing one of the following operations: when initializing random access in the first coverage level, indicating according to the indication information The second access resource initiates random access at the first coverage level, and when the random access is initiated at the first coverage level after the initial time, the contention access resource corresponding to the first coverage level Selecting a third access resource randomly, and using the third access resource to initiate random access at the first coverage level; when initializing or initializing a random access at the first coverage level And the second access resource indicated by the indication information continues to initiate random access under the first coverage level;

a second initiating unit, configured to: when the determination result of the determining unit is negative, when the random access is initiated under the first coverage level after the initial or initial time, The fourth access resource is randomly selected from the contention access resources corresponding to the first coverage level, and the fourth access resource is used to initiate random access at the first coverage level.
A random access device in a wireless communication system, comprising:

Determining a module, configured to determine that the terminal needs to initiate random access under the second coverage level;

The first receiving module is configured to receive a random access request from the terminal on an access resource included in a contention access resource corresponding to the second coverage level.
The device according to claim 10, wherein

The device further includes: a sending module, configured to send indication information to the terminal before determining that the terminal needs to initiate random access in the second coverage level, where the indication information is used to indicate the The terminal initiates random access at the first coverage level, and the second receiving module is configured to receive a random access request initiated by the terminal under the first coverage level;

The determining module includes: a determining unit, configured to determine that the number of random access failures initiated by the terminal at the first coverage level reaches a random access threshold corresponding to the first coverage level.
A storage medium, the storage medium comprising a stored program, wherein the program is executed to perform the method of any one of claims 1 to 7.