CN107690200B

CN107690200B - random access method and terminal

Info

Publication number: CN107690200B
Application number: CN201610641256.XA
Authority: CN
Inventors: 许芳丽; 陈瑞卡; 潘学明
Original assignee: China Academy of Telecommunications Technology CATT
Current assignee: China Academy of Telecommunications Technology CATT; Datang Mobile Communications Equipment Co Ltd
Priority date: 2016-08-05
Filing date: 2016-08-05
Publication date: 2019-12-10
Anticipated expiration: 2036-08-05
Also published as: WO2018024136A1; CN107690200A

Abstract

The invention provides a random access method and a terminal, which relate to the technical field of communication, and the method comprises the following steps: acquiring the replaced access configuration adopted when the terminal randomly accesses the network again after the process of randomly accessing the network; and after the access of the terminal fails in the process of randomly accessing the network, performing the random access again to the network according to the replaced access configuration adopted by the random access again to the network. The scheme of the invention can improve the access success rate of the random access sequence retransmission, thereby shortening the time delay of the whole random access.

Description

Random access method and terminal

Technical Field

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

Background

In 5G NR (New RAT, New radio access technology), due to its characteristics of super large cells and super large user density, when a UE (terminal) wants to access a network according to the requirement of internal high layer service triggering or high layer signaling triggering, the collision probability of random access is increased due to high user density. The collision of multiple attempts will result in further increase of access delay; if the backoff factor of random access is increased, although the probability of failure of the transmission may be reduced to some extent, the delay may also be increased.

meanwhile, different types of slices or services are supported in the 5G system, that is, different delay requirements need to be reflected, and some slices or services have very strict access delay requirements. Therefore, it is necessary to consider the requirement of access delay required by the service after the current random access fails in the initial random access process.

in the current LTE system, the reasons for random access mainly include the following:

1) access from RRC _ IDLE state (also referred to as initial access);

2) A radio link failure initiates RRC (radio resource control) connection re-establishment (also a kind of initial access);

3) The switching process requires random access;

4) When the UE is in an RRC _ CONNECTED (radio resource control _ CONNECTED state), downlink data arrives;

5) When the UE is in RRC _ CONNECTED (radio resource control _ CONNECTED state), uplink data arrives.

In the random access process of the current LTE system, different service delay requirements are not reflected, so that different delay guarantees of services with different delay requirements in the access process cannot be well guaranteed. Meanwhile, because the initial transmission and retransmission resources in the random access process are basically the same, the situation that the initial transmission fails due to collision in this situation cannot be improved well in the retransmission process.

disclosure of Invention

the technical problem to be solved by the present invention is to provide a random access method and a terminal, which can improve the access success rate of random access sequence retransmission, thereby shortening the time delay of the whole random access.

to solve the foregoing technical problem, an embodiment of the present invention provides a random access method, including:

Acquiring the replaced access configuration adopted when the terminal randomly accesses the network again after the process of randomly accessing the network;

and after the access of the terminal fails in the process of randomly accessing the network, performing the random access again to the network according to the replaced access configuration adopted by the random access again to the network.

After the access of the terminal fails in the process of randomly accessing the network, the step of randomly accessing the network again according to the replaced access configuration adopted by the randomly accessing the network again comprises the following steps:

In the process of randomly accessing the network, after N times of access failures, the terminal carries out the random access network again according to the replaced access configuration adopted by the random access network again;

wherein, N is more than or equal to 1 and less than or equal to M, N, M are positive integers, and M is the maximum access frequency in the whole random access process.

the access failure in the process that the terminal accesses the network comprises the following steps: the random access sequence transmitted by the terminal fails to be transmitted or the conflict resolution process in the process of randomly accessing the network fails.

The changed access configuration adopted by the random access network again includes: random access resource configuration or backoff parameters in the random access process.

The changed access configuration adopted by the random access network again includes: when other random access resource configurations under the same network access point are configured, the steps of acquiring the replaced access configuration after the terminal is randomly accessed to the network again after the process of randomly accessing the network comprise:

acquiring a first random access configuration resource adopted by a terminal sent by a network access point through a broadcast message in the process of randomly accessing a network and a second random access configuration resource adopted by a secondary random access network later; or

acquiring a first random access configuration resource carried by a network access point through a system message block, and acquiring a second random access configuration resource adopted by a random access network again after a random access network process fails according to the first random access configuration resource;

Wherein the first random access configuration resource is different from the second random access configuration resource.

the step of acquiring the second random access configuration resource adopted by the random access network again comprises the following steps:

And acquiring a second random access configuration resource sent by the network access point through an MSG2 message or L1/L2 signaling.

After the access of the terminal fails in the process of randomly accessing the network, stopping the random access process, and re-initiating the random access process according to the second random access configuration resource adopted by the random access network again; or

And after the terminal fails to access in the process of randomly accessing the network, replacing the first random access configuration resource with a second random access configuration resource, and restarting the random access process according to the second random access configuration resource adopted by the random access network again.

After the random access network is successfully accessed again, the method further comprises the following steps:

and discarding the second random access configuration resource and recovering the configuration of the first random access configuration resource.

when the random access resource configuration included in the changed access configuration adopted by the random access network is changed to the frequency point, and the changed access configuration adopted by the terminal is obtained after the process of randomly accessing the network and when the terminal is randomly accessed to the network again, the steps of the changed access configuration comprise:

The terminal adopts a first frequency to carry out random access to the network in a high-low frequency overlapping coverage area of the network, and after access fails in the process of random access to the network, a second frequency adopted by the random access network is obtained again;

Wherein the first frequency is a frequency within a frequency range adopted by a high frequency region, and the second frequency is a frequency within a frequency range adopted by a low frequency region; or

The first frequency is a frequency within a frequency range adopted in a low frequency region, and the second frequency is a frequency within a frequency range adopted in a high frequency region.

the step of acquiring the replaced access configuration adopted by the terminal when the terminal is randomly accessed to the network again after the process of randomly accessing the network comprises the following steps:

the terminal resides in a network consisting of a plurality of network access points at a single frequency point, carries out a random network access process in a first cell in the network, and triggers a cell reselection process to acquire a reselected second cell in the network or directly acquire the second cell with the signal intensity different from that of the first cell after the access fails; wherein one network access point is one cell.

the method comprises the steps that a terminal resides in a network formed by a plurality of network access points at a single frequency point, at least one network access point in the plurality of network access points forms a cell, and a first random access configuration resource corresponding to the network access point accessed by the terminal and a second random access configuration resource corresponding to the cell are obtained from a system message block sent by the network access point where the terminal resides.

After the access of the terminal fails in the process of randomly accessing the network, the step of randomly accessing the network again according to the replaced access configuration adopted by the network for random access again comprises the following steps:

After the terminal fails to access in the process of random access according to the first random access configuration resource at the resident network access point, performing random access again to the network according to the second random access configuration resource;

Or

And after the terminal fails to access in the process of random access according to the second random access configuration resource in the resident cell, performing random access again to the network according to the first random access configuration resource.

the step of acquiring the changed access configuration adopted by the terminal when the terminal is randomly accessed to the network again after the process of randomly accessing the network when the random access resource configuration included in the changed access configuration adopted by the random access network again is the access configuration under the monitoring mechanism comprises:

After the access of the terminal random access network process fails, when the detected number of MSG1 is greater than a preset value within a preset time length, obtaining a back-off time parameter adopted by the random access network again; or

after the access of the terminal random access network process fails, monitoring the signal intensity on a preset channel, and when the signal intensity is higher than the preset signal intensity value, acquiring a back-off time parameter adopted by the random access network again.

Monitoring a load indication sent by a network;

and when the load indication indicates that the network load exceeds a preset load value, acquiring a back-off time parameter adopted by the random access network again.

The changed access configuration adopted by the random access network again includes: when the backoff parameter is in the random access process, the step of obtaining the replaced access configuration after the terminal is in the random access network process and when the terminal is in the random access network again comprises the following steps:

Acquiring a first random access configuration resource carried by a network through a system message block;

acquiring a back-off time parameter indication after the first random access process fails according to the first random access configuration resource;

and obtaining the back-off time according to the back-off time parameter indication.

the step of obtaining the indication of the back-off time parameter comprises:

the back-off time parameter indication is obtained through an MSG2 message or through a system message block or through an air interface message which is monitored or through a back-off time parameter indication which is transmitted for the first time.

according to the indication of the back-off time parameter, the step of obtaining the back-off time comprises the following steps:

Obtaining the back-off time corresponding to the current transmission times according to the corresponding relation between the back-off time parameter indication and the transmission times; or

obtaining the backspacing time according to the backspacing time parameter indication, the transmission times and the superposition coefficient; or

And obtaining the back-off time corresponding to the current service according to the corresponding relation between the back-off time parameter indication and the services with different time delay requirement attributes.

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

the acquisition module is used for acquiring the replaced access configuration adopted when the terminal randomly accesses the network again after the process of randomly accessing the network;

And the access module is used for performing random access to the network again according to the replaced access configuration adopted by the random access network again after access fails in the process of randomly accessing the network.

In the process of randomly accessing the network, after N times of access failures, the access module carries out random access again to the network according to the replaced access configuration adopted by the random access again to the network;

wherein, the access failure in the process that the terminal accesses the network comprises the following steps: the random access sequence transmitted by the terminal fails to be transmitted or the conflict resolution process in the process of randomly accessing the network fails.

Wherein the changed access configuration adopted by the random access network again includes: random access resource configuration or backoff parameters in the random access process.

wherein the changed access configuration adopted by the random access network again includes: when other random access resources under the same network access point are configured, the obtaining module includes:

a first obtaining unit, configured to obtain a first random access configuration resource used by a terminal, which is sent by a network access point through a broadcast message, in a process of randomly accessing a network and a second random access configuration resource used by a network to be randomly accessed again later; or

a second obtaining unit, configured to obtain a first random access configuration resource carried by a system message block through a network access point, and obtain a second random access configuration resource adopted by a random access network again after a random access network process fails according to the first random access configuration resource;

the second acquiring unit acquires a second random access configuration resource sent by the network access point through an MSG2 message or an L1/L2 signaling.

Wherein the access module is specifically configured to:

stopping the random access process after the access fails in the process of randomly accessing the network, and restarting the random access process according to the second random access configuration resource adopted by the random access network again; or

and after the access fails in the process of randomly accessing the network, replacing the first random access configuration resource with a second random access configuration resource, and restarting the random access process according to the second random access configuration resource adopted by the random access network again.

Wherein the access module is further configured to: and after the random access network is successfully accessed again, discarding the second random access configuration resource and recovering the configuration of the first random access configuration resource.

Wherein, when the random access resource configuration included in the changed access configuration adopted by the random access network is a changed frequency point, the obtaining module is specifically configured to:

Wherein, when the random access resource configuration included in the changed access configuration adopted by the random access network is a changed network access point, the obtaining module is specifically configured to:

wherein the access module is specifically configured to: after the terminal fails to access in the process of random access according to the first random access configuration resource at the resident network access point, performing random access again to the network according to the second random access configuration resource;

Or

Wherein, when the random access resource configuration included in the replaced access configuration adopted by the random access network is an access configuration under a monitoring mechanism, the obtaining module is specifically configured to: after the access of the terminal random access network process fails, when the detected number of MSG1 is greater than a preset value within a preset time length, obtaining a back-off time parameter adopted by the random access network again; or

wherein, when the random access resource configuration included in the replaced access configuration adopted by the random access network is an access configuration under a monitoring mechanism, the obtaining module is specifically configured to:

monitoring a load indication sent by a network;

wherein the changed access configuration adopted by the random access network again includes: when the backoff parameter is in the random access process, the obtaining module is specifically configured to: acquiring a first random access configuration resource carried by a network through a system message block; acquiring a back-off time parameter indication after the first random access process fails according to the first random access configuration resource; and obtaining the back-off time according to the back-off time parameter indication.

the obtaining of the back-off time parameter indication specifically obtains the back-off time parameter indication through an MSG2 message, or through a system message block, or through an air interface message monitored, or through a back-off time parameter indication transmitted for the first time.

Wherein, when the obtaining module obtains the back-off time according to the back-off time parameter indication, the obtaining module is specifically configured to: obtaining the back-off time corresponding to the current transmission times according to the corresponding relation between the back-off time parameter indication and the transmission times; or obtaining the back-off time according to the back-off time parameter indication, the transmission times and the superposition coefficient; or obtaining the back-off time corresponding to the current service according to the corresponding relation between the back-off time parameter indication and the services with different time delay requirement attributes.

The technical scheme of the invention has the following beneficial effects:

The embodiment of the invention obtains the replaced access configuration adopted when the terminal randomly accesses the network again after the process of randomly accessing the network; and after the access of the terminal fails in the process of randomly accessing the network, performing the random access again to the network according to the replaced access configuration adopted by the random access again to the network. Therefore, the success rate and the real-time performance of retransmission when the terminal is randomly accessed to the network are improved, and the random access transmission delay requirement of specific services and the delay requirement of the whole random access are ensured.

Drawings

fig. 1 is a flowchart of a random access method according to a first embodiment of the present invention;

Fig. 2 is a flowchart of a random access method according to a second embodiment of the present invention;

FIG. 3 is a detailed signaling flow diagram of the embodiment shown in FIG. 2;

FIG. 4 is a detailed signaling flow diagram of the embodiment shown in FIG. 2;

Fig. 5 is a flowchart of a random access method according to a third embodiment of the present invention;

FIG. 6 is a diagram of a communications system deployment scenario;

FIG. 7 is a high and low frequency heterogeneous scene diagram;

fig. 8 is a flowchart of a random access method according to a fourth embodiment of the present invention;

fig. 9 shows a deployment scenario in which multiple TRPs are formed in the same frequency layer, and each TRP is a cell;

Fig. 10 is a flowchart of a random access method according to a fifth embodiment of the present invention;

fig. 11 is a scenario in which a UE resides in a network with a single frequency point and a plurality of TRPs, the plurality of TRPs form a cell and are uniformly managed by an NB (node B);

FIG. 12 is a flowchart illustrating an implementation of the embodiment shown in FIG. 10;

Fig. 13 is a flowchart of a random access method according to a sixth embodiment of the present invention;

Fig. 14 is a flowchart of a random access method according to a seventh embodiment of the present invention;

fig. 15 is a flowchart of a random access method according to an eighth embodiment of the present invention;

FIG. 16 is a flowchart illustrating an implementation of the embodiment shown in FIG. 15;

Fig. 17 is a structural frame diagram of a terminal according to a tenth embodiment of the present invention.

Detailed Description

in order to make the technical problems, technical solutions and advantages of the present invention more apparent, the following detailed description is given with reference to the accompanying drawings and specific embodiments.

The embodiment of the invention provides a method for processing random access failure. The core idea is that after the initial random access fails, a new access mode is adopted to initiate the subsequent random access process.

first embodiment

as shown in fig. 1, a random access method provided by a first embodiment of the present invention includes:

step 11, acquiring the replaced access configuration adopted when the terminal randomly accesses the network again after the process of randomly accessing the network;

in the current LTE mechanism, the initial transmission and retransmission resources in the random access process are basically the same, and in this case, the situation of initial transmission failure due to collision cannot be improved well during retransmission; when the network is randomly accessed again, the replaced access configuration is adopted, so that the success rate and the real-time performance of retransmission are improved when the terminal randomly accesses the network;

Step 12, after the access of the terminal fails in the process of randomly accessing the network, performing the random access again to the network according to the replaced access configuration adopted by the random access again to the network;

Here, the access failure in the process of the terminal accessing the network includes: the random access sequence transmitted by the terminal fails to be transmitted or the conflict resolution process in the process of randomly accessing the network fails.

In addition, in the process of randomly accessing the network, after N times of access failures, the terminal performs random access again to the network according to the replaced access configuration adopted by the random access again to the network;

that is, initiating the random access network by using the replaced access configuration after the random access procedure fails includes:

(1) in the 1-time random access process, the previous N-time access fails (N > -1), and a new mode is adopted to carry out Msg1 retransmission; or

(2) after 1 complete random access failure, the random access process is reinitiated in a new way.

second embodiment

as shown in fig. 2, a random access method provided by a second embodiment of the present invention includes:

the changed access configuration adopted by the random access network again includes: when other random access resources under the same network access point are configured,

step 21, acquiring a first random access configuration resource adopted by a terminal sent by a network access point through a broadcast message in the process of randomly accessing a network and a second random access configuration resource adopted by the network for random access again later; or acquiring a first random access configuration resource carried by a network access point through a system message block, and acquiring a second random access configuration resource adopted by a random access network again after a random access network process fails according to the first random access configuration resource;

Specifically, a second random access configuration resource sent by the network access point through an MSG2 message or an L1/L2 signaling is obtained; wherein the first random access configuration resource is different from the second random access configuration resource;

step 22, after the access of the terminal fails in the process of randomly accessing the network, the terminal stops the random access process and re-initiates the random access process according to the second random access configuration resource adopted by the random access network again; or after the terminal fails to access in the process of randomly accessing the network, replacing the first random access configuration resource with a second random access configuration resource, and restarting the random access process according to the second random access configuration resource adopted by the random access network again.

The specific signaling flow is as shown in fig. 3:

Step 1, a network notifies a random access process in a cell to UE through broadcasting, wherein the initial transmission is configured as Cfg-1, and the retransmission is configured as Cfg-2; (similarly, the network side may configure random access configuration for each retransmission number for the UE, or may set that Cfg-1 is used for initial X-times transmission, Cfg-2 is used for subsequent Y-times transmission, and Cfg-3 … is used for subsequent Z-times);

step 2, UE initiates random access by Cfg-1 configuration;

and 3, after the random access fails, initiating the random access by adopting Cfg-2 configuration in subsequent retransmission.

the specific signaling flow is as shown in fig. 4:

Step 1, UE acquires RACH (random access channel) configuration cfg-1 through system information and stores the configuration cfg-1;

step 2, UE initiates a random access process by using Cfg-1 configuration;

Step 3, the network side directly informs the RACH configuration used by retransmission to be Cfg-2 through L1/L2 signaling; the information can also be directly carried by the Msg2 message, or can be carried by a new L1/L2 signaling independent of the Msg2 message; UE initiates subsequent retransmission according to the Cfg-2 configuration indicated by the signaling;

Step 4, when the RA process fails, the random access sequence is retransmitted by using the configuration of Cfg-2, wherein, the former RA process can be stopped to reinitiate a new random access process, or the current random access process can be not interrupted, and the updated configuration is directly applied for retransmission;

and step 5, after the random access is successful, the UE discards the random access configuration Cfg-2 and recovers the original configuration of Cfg-1. Namely, the second random access configuration resource is discarded, and the configuration of the first random access configuration resource is recovered.

The embodiment of the invention enables the terminal to adopt the changed access configuration when randomly accessing the network again after the process of randomly accessing the network by acquiring other access configurations of the same network access point; and after the access of the terminal fails in the process of randomly accessing the network, performing the random access again to the network according to the replaced access configuration adopted by the random access again to the network. Therefore, the success rate and the real-time performance of retransmission when the terminal is randomly accessed to the network are improved, and the random access transmission delay requirement of specific services and the delay requirement of the whole random access are ensured.

third embodiment

As shown in fig. 5, a third embodiment of the present invention provides a random access method, including:

step 51, the terminal adopts a first frequency to carry out random access to the network in the high-low frequency overlapping coverage area of the network, and after access fails in the process of random access to the network, a second frequency adopted by the random access network is obtained again;

And step 52, after the access of the terminal fails in the process of randomly accessing the network, performing the random access again to the network according to the replaced second frequency adopted by the random access again to the network.

wherein the first frequency is a frequency within a frequency range adopted by a high frequency region, and the second frequency is a frequency within a frequency range adopted by a low frequency region; or the first frequency is a frequency within a frequency range adopted by a low frequency region, and the second frequency is a frequency within a frequency range adopted by a high frequency region.

As shown in fig. 6, in a network deployment and deployment scenario of a future mobile communication system, ultra-dense networking is a trend of development of the future mobile communication system, and under the condition of ultra-dense networking, in order to implement unified control plane management on a large number of distributed processing nodes, part of protocol functions need to be processed in a centralized manner. Thus, a double-layer structure of a centralized processing node and a distributed processing node is formed, the distributed processing node is also called as a TRP (Transmission Reception Point), and the centralized processing node also becomes a CU (Central Unit) or an NR eNB (New RAT eNB). For the centralized processing node, according to different functions, the control plane of the centralized processing node and the user plane of the centralized processing node may be further divided.

As shown in fig. 7, deployment scenario: in a high-low frequency heterogeneous scene, in the same coverage area, a TRP (HF) of a high frequency point and a TRP (LF) of a low frequency point exist, when a terminal stays in the coverage area, the TRP of the low frequency point can be accessed, and the TRP of the high frequency point can also be accessed, in the scene, when the terminal accesses the TRP of the low frequency point in a high-low frequency overlapping coverage area of a network by adopting low frequency, after the access fails, the TRP of the high frequency point can be accessed by adopting high frequency for random access again; certainly, after the high frequency access to the high frequency point TRP fails, the low frequency access to the low frequency point TRP may be used for random access again.

In the embodiment of the invention, the terminal adopts the first frequency to carry out random access to the network in the high-low frequency overlapping coverage area of the network, and after access fails in the process of random access to the network, the second frequency adopted by the random access network is obtained again; after the access of the terminal fails in the process of randomly accessing the network, performing the random access again to the network according to the replaced second frequency adopted by the random access again to the network; therefore, after the access of the low-frequency point fails, the random access of the high-frequency point can be adopted; of course, the low frequency point random access may be adopted after the high frequency point access fails. Therefore, the success rate and the real-time performance of retransmission when the terminal is randomly accessed to the network are improved, and the random access transmission delay requirement of specific services and the delay requirement of the whole random access are ensured.

Fourth embodiment

As shown in fig. 8, a fourth embodiment of the present invention provides a random access method, including:

Step 81, a terminal resides in a network with a single frequency point and a plurality of network access points, performs a random access network process in a first cell in the network, and after access fails, triggers a cell reselection process to acquire a reselected second cell in the network or directly acquires a second cell with a signal strength different from that of the first cell; wherein one network access point is a cell;

and 82, after the access of the terminal fails in the process of randomly accessing the network, performing the random access again to the network according to the replaced second cell adopted by the random access again to the network.

As the scenario deployment shown in fig. 9, the same frequency layer is composed of a plurality of TRPs, and each TRP is a cell.

the specific implementation process 1 of the method comprises the following steps:

the UE resides in a network consisting of a plurality of TRPs at a single frequency point, and each TRP is a cell;

Step 1, UE firstly resides in a cell 1 and initiates random access through the cell 1;

Step 2, if the random access fails for N times before, or the access fails in the whole random access process, the UE triggers the cell selection and reselection process to select the cell 2;

Step 3, the UE initiates the subsequent random access procedure (corresponding to the previous N failures) directly to the cell 2, or re-initiates the random access procedure (corresponding to the access failure of the whole random access procedure).

The specific implementation process 2 of the method comprises the following steps:

Step 2, if the random access fails for N times before, or the random access fails in the whole process, the UE directly switches to a cell 2 with the signal intensity of second strength;

step 3, the UE directly initiates the subsequent random access procedure (corresponding to the previous N failures) in the cell 2, or re-initiates the random access procedure (corresponding to the access failure of the whole random access procedure).

The fourth embodiment of the present invention can improve the success rate and real-time of retransmission when the terminal randomly accesses the network by replacing another network access point, thereby ensuring the random access transmission delay requirement of a specific service and the delay requirement of the whole random access.

fifth embodiment

as shown in fig. 10, a fifth embodiment of the present invention provides a random access method, including:

Step 101, a terminal resides in a network with a single frequency point composed of a plurality of network access points, at least one network access point in the plurality of network access points forms a cell, and a first random access configuration resource corresponding to the network access point accessed by the terminal and a second random access configuration resource corresponding to the cell are obtained from a system message block sent by the network access point where the terminal resides;

102, after the terminal fails to access in the process of random access according to the first random access configuration resource at the resident network access point, performing random access again to the network according to the second random access configuration resource; or the terminal performs random access again to the network according to the first random access configuration resource after access failure in the process of performing random access according to the second random access configuration resource in the resident cell of the terminal.

as shown in the scenario deployment shown in fig. 11, the UE resides in a network with a single frequency point and a plurality of TRPs, and the plurality of TRPs form a cell and are managed by an NB (node B) in a unified manner.

As shown in fig. 12, a specific implementation flow of the method includes:

step 1, a network configures two-stage RACH (random access channel) resources to UE through SIB (system information block);

Step 2, the UE firstly resides in the TRP and initiates random access through the RACH resource at the TRP level; the random access procedure is used for transmission and reception through a TRP-related reference signal;

Step 3, after TRP level random access fails, initiating a random access process through RACH resources of a cell level; the random access procedure is used for transmission and reception by cell level reference signals.

of course, if the UE first uses the cell-level RACH resource to initiate the random access procedure, after the access failure, the UE may also switch to use the TRP-level RACH resource to initiate the random access.

the embodiment of the invention realizes that in a network with a single frequency point consisting of a plurality of TRPs (channel temporary assignment) where the UE resides, the plurality of TRPs form a cell, and in a scene managed by NB (node B) in a unified way, after the random access of TRP level fails, a random access process is initiated through RACH (random access channel) resources of the cell level; the random access process can also be initiated by adopting the cell-level RACH resources, and after the access fails, the random access can also be initiated by adopting the TRP-level RACH resources; therefore, the success rate and the real-time performance of retransmission when the terminal is randomly accessed to the network can be improved, and the random access transmission delay requirement of specific services and the delay requirement of the whole random access can be ensured.

Sixth embodiment

As shown in fig. 13, a sixth embodiment of the present invention provides a random access method, including:

step 131, after the access of the terminal random access network process fails, when the number of detected MSGs 1 is greater than a preset value within a preset time length, obtaining a back-off time parameter adopted by the random access network again; or after the access fails in the process of the terminal random access network, monitoring the signal intensity on a preset channel, and when the signal intensity is higher than the preset signal intensity value, acquiring a back-off time parameter adopted by the random access network again;

step 132, after the terminal returns back for a period of time, the terminal then initiates a random access procedure.

the specific implementation process of the method comprises the following steps: after the initial random access fails, the mobile station will,

The UE monitors the signal strength or Msg1 sent by other users on the Msg1 or a special channel before initiating a random access process;

and when the number of the detected msgs 1 in the predefined time length is lower than a predefined value or the channel strength is lower than a preconfigured value, directly initiating a random access process, otherwise, returning for a period of time, initiating the random access process, or continuing LBT monitoring to initiate the random access process.

Seventh embodiment

as shown in fig. 14, a seventh embodiment of the present invention provides a random access method, including:

Step 141, monitoring a load indication sent by the network, and when the load indication indicates that the network load exceeds a preset load value, acquiring a back-off time parameter adopted by the random access network again;

and step 142, after the terminal backs off for a period of time, the terminal sends out a random access process.

the network displays a network load (load) indication to the UE, the UE judges whether to initiate random access according to the indication, and if not, the UE reads the load information again within the T time of back off.

In the embodiment, the terminal backs off for a period of time after the access fails through a monitoring mechanism, and then performs random access, so that the success rate and the real-time performance of retransmission when the terminal randomly accesses a network can be improved, and the random access transmission delay requirement of a specific service and the delay requirement of the whole random access can be ensured.

eighth embodiment

As shown in fig. 15, an eighth embodiment of the present invention provides a random access method, including:

step 151, acquiring a first random access configuration resource carried by a network through a system message block;

step 152, after the first random access procedure fails according to the first random access configuration resource, obtaining a back-off time parameter indication;

Specifically, the back-off time parameter indication may be obtained through an MSG2 message, or through a system message block, or through an air interface message that is monitored, or through a back-off time parameter indication that is transmitted for the first time;

step 153, obtaining the back-off time according to the back-off time parameter indication;

specifically, the backoff time corresponding to the current transmission times can be obtained according to the corresponding relationship between the backoff time parameter indication and the transmission times; or obtaining the back-off time according to the back-off time parameter indication, the transmission times and the superposition coefficient; or obtaining the back-off time corresponding to the current service according to the corresponding relation between the back-off time parameter indication and the services with different time delay requirement attributes;

in step 154, the terminal enters the random access network again after returning for a period of time.

As shown in fig. 16, the specific random access procedure includes:

step 1, UE acquires RACH (random access channel) configuration Cfg-1 through system information;

step 2, UE initiates a random access process by using Cfg-1 configuration;

Step 3, if the UE can pass through system information or monitor information of an air interface in advance, or a BI parameter transmitted for the first time, directly using the BI parameter to carry out rollback processing and then sending out a random access process;

Step 4, the UE receives the Msg2, wherein the Msg2 carries BI;

Step 5, the UE searches the actual value corresponding to the BI according to the current transmission times and the times and performs backoff; the searching process can be searching according to corresponding tables with different transmission times, can also be calculated according to backspacing time parameter indication, transmission times and superposition coefficients, and can also be calculating according to the corresponding relation between the backspacing time parameter indication and services with different time delay requirement attributes to obtain actual values corresponding to BI;

step 6, after returning for a certain time, UE re-initiates a random access process; the table or coefficient corresponding to different transmission times may be configured to the UE through signaling.

In this embodiment of the present invention, different transmission times correspond to different backoff lengths, that is, if 1 transmission fails, a backoff length is a, 2 transmission fails, a backoff length is B, 3 transmission fails, and a backoff length is C, where A, B, C are different.

In the embodiment, the terminal backs for a period of time after the access fails through a back-off mechanism, and then performs random access, so that the success rate and the real-time performance of retransmission when the terminal randomly accesses a network can be improved, and the random access transmission delay requirement of a specific service and the delay requirement of the whole random access can be ensured.

In the above embodiment of the present invention, when the replaced access configuration is an access configuration resource, the access configuration resource may include code division resources such as a time-frequency resource of a random access channel, a transmission point of a home network, an uplink synchronization code or a preamble sequence; wherein the access configuration resource can be carried by Msg2, wherein the random access resource required for retransmission carried by Msg2 can be carried in any Msg2 message.

In the above embodiments of the present invention, different backoff parameters (time for controlling UE to perform preamble retransmission) are used to perform backoff, and then random access is initiated; the eNodeB informs the UE of a backoff value through random access response, if the UE needs to perform preamble retransmission, the UE randomly selects a value from 0 to the backoff value as the backoff time, and performs preamble retransmission after the backoff time is over.

wherein the different backoff parameters may be: 1) different backoff parameters are given to different services; 2) different transmission times are given to different backoff parameters; the Backoff parameter can be displayed to a specific value, or can be the same BI, and different services or different transmission times are mapped to different values;

When the backoff parameter is related to the transmission times, the backoff value of the initial access also needs to be known when the UE is required to initially access, and the value can be informed to the UE through L1/L2/L3 signaling;

in the LTE system, the overload control requirement of RACH is relaxed relative to the previous mobile communication system, because in LTE, random access occupies a separate time-frequency resource and does not generate interference to other uplink channels. Generally, the collision probability of RACH is at a relatively low level, but it also results in access failure due to preamble collision of UEs because there are too many UEs accessing on one PRACH.

In order to reduce the possibility of this occurrence, a fallback mechanism is introduced in LTE to control the time for the UE to perform preamble retransmission.

The eNodeB informs the UE of a backoff value through random access response, if the UE needs to perform preamble retransmission, the UE randomly selects a value from 0 to the backoff value as the backoff time, and performs preamble retransmission after the backoff time is over.

in the above embodiment of the present invention, after the random access fails, when a new access mode is adopted to perform random access to the network again, the random access configuration after replacement may be adopted or after a period of backoff, the access may be performed again, thereby improving the success rate and real-time performance of retransmission when the terminal randomly accesses the network, and ensuring the random transmission delay requirement of a specific service and the delay requirement of the overall random access.

Ninth embodiment

The ninth embodiment of the present invention also provides a terminal, including:

Wherein the access module is specifically configured to:

wherein the access module is specifically configured to:

Or

Monitoring a load indication sent by a network;

wherein the changed access configuration adopted by the random access network again includes: when the backoff parameter is in the random access process, the obtaining module is specifically configured to:

Wherein, when the obtaining module obtains the back-off time according to the back-off time parameter indication, the obtaining module is specifically configured to:

The embodiment of the terminal is a device corresponding to the method, and all implementation manners of the embodiment of the method are applicable to the embodiment of the device, and the same technical effect can be achieved.

Tenth embodiment

as shown in fig. 17, a tenth embodiment of the present invention provides a terminal including:

The transceiver is used for acquiring the replaced access configuration adopted when the terminal randomly accesses the network again after the process of randomly accessing the network;

and the processor is used for performing random access again to the network according to the replaced access configuration adopted by the random access again after the access fails in the process of randomly accessing the network.

in this embodiment, the processor is coupled to the memory; the memory is used for storing programs and data used by the processor when executing operations; acquiring the replaced access configuration adopted when the terminal randomly accesses the network again after the process of randomly accessing the network; when the processor calls and executes the program and the data stored in the memory, after the access fails in the process of randomly accessing the network, the network is randomly accessed again according to the replaced access configuration adopted by the network.

The bus architecture, which may include any number of interconnected buses and bridges, may also link various other circuits such as peripherals, voltage regulators, power management circuits, etc., which are well known in the art, and therefore, will not be described any further herein. The transceiver may be a number of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium. The processor is responsible for managing the bus architecture and the usual processing, and the memory may store data used by the processor in performing operations.

the processor performs random access to the network again according to the replaced access configuration adopted by the random access network again after access fails for N times in the process of randomly accessing the network;

Wherein the changed access configuration adopted by the random access network again includes: when other random access resources under the same network access point are configured, the transceiver is specifically configured to: acquiring a first random access configuration resource adopted by a terminal sent by a network access point through a broadcast message in the process of randomly accessing a network and a second random access configuration resource adopted by a secondary random access network later; or acquiring a first random access configuration resource carried by a network access point through a system message block, and acquiring a second random access configuration resource adopted by a random access network again after a random access network process fails according to the first random access configuration resource; wherein the first random access configuration resource is different from the second random access configuration resource.

Wherein the transceiver acquires a second random access configuration resource sent by the network access point through MSG2 message or L1/L2 signaling.

Wherein the processor is specifically configured to: stopping the random access process after the access fails in the process of randomly accessing the network, and restarting the random access process according to the second random access configuration resource adopted by the random access network again; or after the access fails in the process of randomly accessing the network, replacing the first random access configuration resource with a second random access configuration resource, and restarting the random access process according to the second random access configuration resource adopted by the random access network again.

Wherein the processor is further configured to: and after the random access network is successfully accessed again, discarding the second random access configuration resource and recovering the configuration of the first random access configuration resource.

Wherein, when the random access resource configuration included in the changed access configuration adopted by the random access network is a changed frequency point, the transceiver is specifically configured to: the terminal adopts a first frequency to carry out random access to the network in a high-low frequency overlapping coverage area of the network, and after access fails in the process of random access to the network, a second frequency adopted by the random access network is obtained again;

Wherein, when the random access resource configuration included in the changed access configuration adopted by the random access network is a changed network access point, the transceiver is specifically configured to: the terminal resides in a network consisting of a plurality of network access points at a single frequency point, carries out a random network access process in a first cell in the network, and triggers a cell reselection process to acquire a reselected second cell in the network or directly acquire the second cell with the signal intensity different from that of the first cell after the access fails; wherein one network access point is one cell.

Wherein, when the random access resource configuration included in the changed access configuration adopted by the random access network is a changed network access point, the transceiver is specifically configured to: the method comprises the steps that a terminal resides in a network formed by a plurality of network access points at a single frequency point, at least one network access point in the plurality of network access points forms a cell, and a first random access configuration resource corresponding to the network access point accessed by the terminal and a second random access configuration resource corresponding to the cell are obtained from a system message block sent by the network access point where the terminal resides.

Wherein the processor is specifically configured to: after the terminal fails to access in the process of random access according to the first random access configuration resource at the resident network access point, performing random access again to the network according to the second random access configuration resource; or the terminal performs random access again to the network according to the first random access configuration resource after access failure in the process of performing random access according to the second random access configuration resource in the resident cell of the terminal.

wherein, when the random access resource configuration included in the replaced access configuration adopted by the random access network is an access configuration under a monitoring mechanism, the transceiver is specifically configured to: after the access of the terminal random access network process fails, when the detected number of MSG1 is greater than a preset value within a preset time length, obtaining a back-off time parameter adopted by the random access network again; or after the access of the terminal random access network process fails, monitoring the signal intensity on a preset channel, and when the signal intensity is higher than the preset signal intensity value, acquiring a back-off time parameter adopted by the random access network again.

Wherein, when the random access resource configuration included in the replaced access configuration adopted by the random access network is an access configuration under a monitoring mechanism, the transceiver is specifically configured to: monitoring a load indication sent by a network; and when the load indication indicates that the network load exceeds a preset load value, acquiring a back-off time parameter adopted by the random access network again.

wherein the changed access configuration adopted by the random access network again includes: when the backoff parameter is in the random access process, the transceiver is specifically configured to: acquiring a first random access configuration resource carried by a network through a system message block; acquiring a back-off time parameter indication after the first random access process fails according to the first random access configuration resource; and obtaining the back-off time according to the back-off time parameter indication.

Wherein, when the transceiver obtains the back-off time according to the back-off time parameter indication, the transceiver is specifically configured to: obtaining the back-off time corresponding to the current transmission times according to the corresponding relation between the back-off time parameter indication and the transmission times; or

obtaining the backspacing time according to the backspacing time parameter indication, the transmission times and the superposition coefficient; or obtaining the back-off time corresponding to the current service according to the corresponding relation between the back-off time parameter indication and the services with different time delay requirement attributes.

In the above embodiment of the present invention, after the random access fails, when a new access mode is adopted to perform random access to the network again, the random access configuration after replacement or the random access configuration after a certain time back-off may be adopted to perform access again, thereby improving the success rate and the real-time performance of retransmission when the terminal randomly accesses the network, and ensuring the random transmission delay requirement of a specific service and the delay requirement of the overall random access.

While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims

1. a random access method, comprising:

Acquiring the replaced access configuration adopted when the terminal randomly accesses the network again after the process of randomly accessing the network; the changed access configuration adopted by the random access network again includes: configuration of random access resources or backoff parameters in the random access process; the random access resource configuration comprises: at least one of other random access resource configurations, changed frequency points, changed network access points and access configurations under a monitoring mechanism under the same network access point;

2. the random access method according to claim 1, wherein the step of performing the random access again to the network according to the changed access configuration adopted by the random access again after the access failure of the terminal in the process of randomly accessing to the network comprises:

3. The random access method of claim 1, wherein the access failure during the access of the terminal to the network comprises: the random access sequence transmitted by the terminal fails to be transmitted or the conflict resolution process in the process of randomly accessing the network fails.

4. The random access method according to claim 1, wherein the changed access configuration adopted by the random access network again comprises: when other random access resource configurations under the same network access point are configured, the steps of acquiring the replaced access configuration after the terminal is randomly accessed to the network again after the process of randomly accessing the network comprise:

5. The random access method according to claim 4, wherein the step of obtaining the second random access configuration resource used by the random access network again comprises:

6. The random access method according to claim 5, wherein the step of performing the random access again to the network according to the changed access configuration adopted by the random access again after the access failure of the terminal in the process of randomly accessing to the network comprises:

After the access of the terminal fails in the process of randomly accessing the network, stopping the random access process, and re-initiating the random access process according to the second random access configuration resource adopted by the random access network again; or after the terminal fails to access in the process of randomly accessing the network, replacing the first random access configuration resource with a second random access configuration resource, and restarting the random access process according to the second random access configuration resource adopted by the random access network again.

7. The random access method of claim 6, wherein after the random access network is successfully accessed again, the method further comprises:

8. the random access method according to claim 1, wherein the step of obtaining the changed access configuration adopted by the terminal when the terminal re-randomly accesses the network after the random access network process when the changed access configuration adopted by the re-random access network includes the random access resource configuration as the changed frequency point comprises:

9. the random access method according to claim 1, wherein the step of acquiring the changed access configuration adopted by the terminal when the terminal re-randomly accesses the network after the random access network process when the changed access configuration adopted by the re-random access network includes that the random access resource is configured as the changed network access point, comprises:

10. the random access method according to claim 1, wherein the step of acquiring the changed access configuration adopted by the terminal when the terminal re-randomly accesses the network after the random access network process when the changed access configuration adopted by the re-random access network includes that the random access resource is configured as the changed network access point, comprises:

11. the random access method according to claim 10, wherein the step of performing the random access again to the network according to the changed access configuration adopted by the random access again after the access of the terminal fails in the process of performing the random access to the network comprises:

or

12. The random access method according to claim 1, wherein the step of acquiring the changed access configuration adopted by the terminal when the terminal re-randomly accesses the network after the random access network process when the random access resource included in the changed access configuration adopted by the re-randomly accesses the network is configured as the access configuration under the monitoring mechanism comprises:

13. The random access method according to claim 1, wherein the step of acquiring the changed access configuration adopted by the terminal when the terminal re-randomly accesses the network after the random access network process when the random access resource included in the changed access configuration adopted by the re-randomly accesses the network is configured as the access configuration under the monitoring mechanism comprises:

Monitoring a load indication sent by a network;

14. The random access method according to claim 1, wherein the changed access configuration adopted by the random access network again comprises: when the backoff parameter is in the random access process, the step of obtaining the replaced access configuration after the terminal is in the random access network process and when the terminal is in the random access network again comprises the following steps:

15. the random access method according to claim 14, wherein the step of obtaining the back-off time parameter indication comprises:

16. the random access method according to claim 14 or 15, wherein the step of obtaining the back-off time according to the back-off time parameter indication comprises:

17. a terminal, comprising:

the acquisition module is used for acquiring the replaced access configuration adopted when the terminal randomly accesses the network again after the process of randomly accessing the network; the changed access configuration adopted by the random access network again includes: configuration of random access resources or backoff parameters in the random access process; the random access resource configuration comprises: at least one of other random access resource configurations, changed frequency points, changed network access points and access configurations under a monitoring mechanism under the same network access point;

18. The terminal of claim 17, wherein the access module performs a random access again to the network according to the changed access configuration adopted by the random access again after failing to access N times in a process of randomly accessing to the network;

19. The terminal of claim 17, wherein the access failure during the access of the terminal to the network comprises: the random access sequence transmitted by the terminal fails to be transmitted or the conflict resolution process in the process of randomly accessing the network fails.

20. the terminal of claim 17, wherein the changed access configuration adopted by the random access network comprises: when other random access resources under the same network access point are configured, the obtaining module includes:

21. the terminal of claim 20, wherein the second obtaining unit obtains the second random access configuration resource sent by the network access point through MSG2 message or L1/L2 signaling.

22. The terminal of claim 21, wherein the access module is specifically configured to:

23. The terminal of claim 22, wherein the access module is further configured to: and after the random access network is successfully accessed again, discarding the second random access configuration resource and recovering the configuration of the first random access configuration resource.

24. The terminal according to claim 17, wherein when the changed access configuration adopted by the random access network again includes a random access resource configuration as a changed frequency point, the obtaining module is specifically configured to:

25. The terminal according to claim 17, wherein when the changed access configuration adopted by the random access network again includes a random access resource configured as a changed network access point, the obtaining module is specifically configured to:

26. The terminal according to claim 17, wherein when the changed access configuration adopted by the random access network again includes a random access resource configured as a changed network access point, the obtaining module is specifically configured to:

27. The terminal of claim 26, wherein the access module is specifically configured to:

Or

28. the terminal according to claim 17, wherein when the random access resource configuration included in the replaced access configuration adopted by the random access network is an access configuration under a monitoring mechanism, the obtaining module is specifically configured to:

29. the terminal according to claim 17, wherein when the random access resource configuration included in the replaced access configuration adopted by the random access network is an access configuration under a monitoring mechanism, the obtaining module is specifically configured to:

monitoring a load indication sent by a network;

30. the terminal of claim 17, wherein the changed access configuration adopted by the random access network comprises: when the backoff parameter is in the random access process, the obtaining module is specifically configured to:

31. the terminal according to claim 30, wherein the indication of obtaining the back-off time parameter is specifically obtained through an MSG2 message, or through a system message block, or through an overheard air interface message, or through an initially transmitted indication of the back-off time parameter.

32. The terminal according to claim 30 or 31, wherein the obtaining module, when obtaining the back-off time according to the back-off time parameter indication, is specifically configured to: