WO2010099659A1 - Method and device for processing random access procedure - Google Patents

Abstract

A method for processing a random access procedure is disclosed by the embodiment of the present invention, and includes the following steps: the MAC layer enters into random access failure mode; if the MAC layer continues the current random access procedure, the MAC layer, after selection, implements the new random access procedure indicated by the RRC layer, and if the MAC layer stops the current random access procedure, the MAC layer implements the new random access procedure indicated by the RRC layer. In addition, the present invention also discloses a device for processing a random access procedure. By using the technical solutions provided by the embodiments of the present invention, it is ensured that the random access procedure caused by RRC connection reconstruction has a higher priority, and thus the waste of random access resources is avoided.

Description

 Processing method and device for random access process

Technical field

 The present invention relates to the field of communications technologies, and in particular, to a method and an apparatus for processing a random access problem.

Background technique

 The random access in LTE is divided into a competitive mode and a non-competitive mode. The random access process of the competitive mode is divided into four steps, as shown in Figure 1:

 Message 1. The UE sends a random access preamble to the eNB (access preamble);

 Message 2. The eNB sends TA (time advance) information, temporary C-RNTI (Cell Radio Network Temporary Identity), and allocates uplink resources to the UE;

 After the UE successfully receives the message 2, the MAC layer needs to buffer the uplink transmission message to be transmitted in the message 3.

 Message 3. The UE uses the resource allocated by the message 2 to send a resource request on the uplink shared channel, and performs collision detection.

 In the random access procedure, a MAC PDU (Media Access Control Protocol Data Unit) of a C-RNTI MAC CE (Media Access Control Unit) or a CCCH SDU (Common Control Channel Service Data Unit) is transmitted on the uplink shared channel. Because the C-RMTI MAC CE and the CCCH SDU both contain the unique identifier of the UE, the UE can independently select the preamble and the PRACH (Physical Random Access Channel) resources. If different UEs select the same preamble and PRACH, a collision occurs, so the message 3 can be used for conflict detection.

 Message 4. The eNB feeds back the resource allocation of the data and indicates whether the collision detection is successful.

 In the non-contention mode random access procedure, the eNB allocates a dedicated preamble and PRACH to the UE, so the random access process in the non-contention mode is divided into three steps, as shown in Figure 2:

Message 0: The eNB allocates a Dedicated preamble to the UE and a dedicated PRACH resource that can be used by the UE; ", ^^, , . . . Message 2, the eNB sends TA (time advance) information, the temporary C-RNTI, and allocates resources for the UE. In the non-contention mode, the UE does not correctly receive the message 2 sent by the eNB. In the contention mode, if the UE does not correctly receive the message 2 or the message 4 sent by the eNB, the random access procedure may fail. The UE starts a timer when the preamble is sent for the first time. When the timer is not stopped, if the currently failed random access procedure is in the non-contention mode, the UE immediately initiates the next random access procedure from message 1. Until the random access procedure succeeds, the timer is stopped; if the currently failed random access procedure is the contention mode, the backoff (the maximum time interval of two random accesses) is set in the message 2, and the UE is at 0 and A random number is selected between the set backoffs as the time interval of two random accesses. After the time interval between the two random accesses expires, starting from the message 1, the next random access process is initiated. The timer is stopped until the random access procedure is successful. If the timer stops and the random access procedure is still unsuccessful, the random access procedure is stopped.

 When the UE sends the random access preamble, the preamble transmission counter is started. When the preamble is sent once, the counter is incremented by 1. When the preamble transmission counter reaches the maximum number of transmissions plus one, the MAC layer of the UE sends a random access problem indication to the RRC layer. The RRC layer initiates an RRC connection re-establishment process, and the RRC connection re-establishment triggers the MAC layer to start a new random access procedure, as shown in FIG. 3: 301. The MAC layer of the UE sends a random access problem indication to the RRC layer, and continues the MAC layer current. Random access procedure;

 302. After receiving the problem indication, the RRC layer of the UE initiates an RRC connection re-establishment process, instructing the MAC layer to start a new random access procedure.

 At this time, there are two random access procedures in the MAC layer, which are the current random access procedure of the MAC layer and the new random access procedure indicated by the RRC layer, and the MAC layer decides to continue the current random access procedure or perform the RRC layer according to the implementation of the UE. Indicates the new random access procedure. The MAC layer handles the competition of the random access process caused by the new and old random access procedures, resulting in waste of random access resources.

Summary of the invention

 The main technical problem to be solved by the embodiments of the present invention is to provide a processing method and apparatus for a random access procedure.

 For the purpose of implementing the embodiments of the present invention, the following technical solutions are provided in the following embodiments: A method for processing a random access process, including:

 The MAC layer enters a random access failure mode;

If the MAC layer stops the current random access procedure, the MAC layer performs a new random indication of the RRC indication. Access process

 If the MAC layer continues the current random access procedure, the MAC layer selects and performs a new random access procedure indicated by the RRC layer.

 A processing device for a random access process, comprising:

 a confirmation module, configured to confirm that the MAC layer enters a random access mode;

 a processing module, after the MAC layer enters the random access mode, the MAC layer stops the current random access procedure, and performs a new random access procedure indicated by the RRC layer; or if the MAC layer continues the current random access procedure, the selection is performed A new random access procedure indicated by the RRC layer.

 The MAC layer enters the random access failure mode. If the MAC layer stops the current random access procedure, after the RRC connection reestablishment triggers the RRC layer to instruct the MAC layer to initiate a new random access procedure, the MAC layer performs the new random access indicated by the RRC layer. If the MAC layer continues the current random access procedure, after the RRC connection reestablishment triggers the RRC layer to instruct the MAC layer to initiate a new random access procedure, the MAC layer has a current random access procedure and a new random indication indicated by the RRC layer. In the access procedure, after the MAC is selected, a new random access procedure indicated by the RRC layer is performed. The new random access procedure caused by the RRC connection reestablishment is guaranteed to have a higher priority, and the current random access procedure of the MAC layer and the new random access procedure caused by the RRC connection reestablishment are avoided, thereby avoiding random access resources. waste.

DRAWINGS

 Figure 1 is a flow chart of random access in a competitive mode;

 2 is a flow chart of random access in a non-contention mode;

 FIG. 3 is a flowchart of a conventional random access processing manner;

 4 is a flowchart of Embodiment 1 of the present invention;

 Figure 5 is a flowchart of Embodiment 2 of the present invention;

 6 is a flowchart of Embodiment 3 of the present invention;

 7 is a flow chart of an apparatus according to an embodiment of the present invention.

detailed description

 In order to make the objects, technical solutions and advantages of the embodiments of the present invention more clear, the embodiments of the present invention are further described in detail below.

In the non-contention mode, the UE does not receive the message 2 sent by the eNB. In the contention mode, if the UE does not receive the message 2 or the message 4 sent by the eNB, the random access procedure fails. Random loss After the failure, the UE starts a timer when the preamble is sent for the first time. When the timer is not stopped, if the currently failed random access procedure is in the non-competitive mode, the UE immediately initiates the next random start from message 1. The access process is performed until the random access procedure is successful, and the timer is stopped. If the currently failed random access procedure is in the contention mode, the UE selects a random number between 0 and backoff as two random accesses. After the time interval between the two random accesses expires, starting from message 1, the next random access procedure is initiated until the random access procedure is successful, and the timer is stopped, as shown in FIG. A flowchart of Embodiment 1 of the present invention is specifically:

 401. The MAC layer enters a random access failure mode.

 When the MAC layer of the UE sends the random access preamble, the preamble transmission counter is also started. The counter is incremented by one every time the preamble is sent. When the preamble transmission counter reaches the maximum number of transmissions plus one, the MAC layer of the UE sends a random to the RRC layer. Access problem indication.

 402a, if the media access control MAC layer stops the current random access procedure, the MAC layer performs a new random access procedure indicated by the RRC layer; or

 402b. If the MAC layer continues the current random access procedure, the MAC layer selects and performs a new random access procedure indicated by the RRC layer.

 After the MAC layer enters the random access failure mode, the MAC layer initiates a new random access procedure indicated by the RRC connection reestablishment after receiving the indication of the RRC connection reestablishment sent by the RRC layer.

 In step 402a, if the MAC layer stops the current random access procedure, the method further includes: resetting the value of the preamble sending counter and the backoff.

 If the random access procedure is in the competition mode, the message 3 buffer needs to be cleared.

 Because the message 3 is an uplink transmission message of the MAC control unit or the CCCH SDU of the C-RNTI in the random access process in the contention mode, before the message 3 is successfully sent, the MAC layer needs to slow down the uplink transmission message in the message 3. After the MAC layer stops the current random access procedure, the message 3 buffer is cleared, and the resources occupied by the buffer are released.

The MAC layer enters the random access failure mode. If the MAC layer stops the current random access procedure, after the RRC connection reestablishment triggers the RRC layer to instruct the MAC layer to initiate a new random access procedure, the MAC layer performs the new random access indicated by the RRC layer. If the MAC layer continues the current random access procedure, when the RRC connection re-establishment triggers the RRC layer to instruct the MAC layer to initiate a new random access procedure, The MAC layer has a current random access procedure and a new random access procedure indicated by the RRC layer, and the MAC selects a new random access procedure indicated by the RRC layer. The new random access procedure caused by the RRC connection reestablishment is guaranteed to have a higher priority, and the current random access procedure of the MAC layer and the new random access procedure caused by the RRC connection reestablishment are avoided, thereby avoiding random access resources. waste.

 After the preamble transmission counter of the UE reaches the maximum number of transmissions plus one, the current MAC layer random access procedure is stopped, and the preamble transmission counter and the backoff value are reset. If the random access procedure is the competition mode, the message 3 needs to be cleared. Buffering, releasing the occupied resources, as shown in FIG. 5, is a flowchart of Embodiment 2 of the present invention, specifically:

 501. The MAC layer of the UE sends a random access problem indication to the RRC layer, and stops the current random access procedure of the MAC layer, and resets the preamble sending counter and the backoff value. If the current random access mode is a random connection of the contention mode. Into the process, you need to clear the message 3 buffer at the same time. Because the message 3 includes the MAC control unit of the C-RNTI or the uplink transmission message of the CCCH SDU in the random access procedure in the contention mode, the MAC layer needs to buffer the uplink transmission message in the message 3 before the message 3 is successfully transmitted. After the MAC layer stops the current random access procedure, the message 3 buffer is cleared, and the resources occupied by the buffer are released.

 502. The RRC layer instructs the MAC layer to trigger a new random access procedure caused by the RRC connection reestablishment. After receiving the problem indication, the RRC layer of the UE decides whether to initiate an RRC connection reestablishment process.

 If the RRC connection re-establishment is initiated, the RRC connection re-establishment indicates that the MAC layer starts a new random access procedure, and the MAC layer performs a new random access procedure indicated by the RRC layer;

 If the RRC connection re-establishment is not initiated, the RRC layer resets the MAC layer.

 The MAC layer enters the random access failure mode. If the MAC layer stops the current random access procedure, after the RRC connection reestablishment triggers the RRC layer to instruct the MAC layer to initiate a new random access procedure, the MAC layer performs the new random access indicated by the RRC layer. The process ensures that the new random access procedure caused by the RRC connection reestablishment has a higher priority, avoids the competition of the new random access procedure initiated by the MAC layer and the RRC connection reestablishment, thereby avoiding randomness. Waste of access resources.

After the preamble transmission counter of the UE reaches the maximum number of transmissions plus one, the MAC layer continues the current random access procedure. At this time, the MAC layer includes two random access procedures, which are the current random access procedure of the MAC layer and the new indication by the RRC layer. During the random access procedure, the MAC layer shall select and perform RRC The layer indicates the new random access procedure. As shown in FIG. 6 , the flowchart of the third embodiment of the present invention is specifically: 601: After the MAC layer of the UE sends a random access problem indication to the RRC layer, the current random access procedure is continued;

 602. The RRC layer instructs the MAC layer to trigger a new random access procedure caused by the RRC connection reestablishment, and the MAC layer selects to perform a new random access procedure indicated by the RRC layer.

 After receiving the problem indication by the RRC layer of the UE, the RRC layer determines whether to initiate an RRC connection re-establishment process;

 If the RRC layer initiates an RRC connection re-establishment process, the RRC connection re-establishment process triggers a new random access procedure, where the MAC layer includes a current random access procedure and a new random access procedure indicated by the RRC layer, and the MAC layer selects the RRC layer to indicate New random access procedure;

 If the RRC connection reestablishment procedure is not initiated, the RRC layer resets the MAC layer and stops the current random access procedure of the MAC layer.

 The MAC layer enters the random access failure mode. If the MAC layer continues the current random access procedure, when the RRC connection reestablishment triggers the RRC layer to instruct the MAC layer to initiate a new random access procedure, the MAC layer has the current random access procedure. And a new random access procedure indicated by the RRC layer, after the MAC selection, a new random access procedure indicated by the RRC layer is performed. The new random access procedure caused by the RRC connection reestablishment is guaranteed to have a higher priority, and the current random access procedure of the MAC layer and the new random access procedure caused by the RRC connection reestablishment are avoided, thereby avoiding random access resources. waste.

 As shown in FIG. 7 , it is a flowchart of an apparatus according to an embodiment of the present invention, where the apparatus specifically includes: an acknowledgment module 701, configured to confirm that a MAC layer enters a random access failure mode;

 The processing module 702 is configured to: after the MAC layer enters the random access mode, the MAC layer stops the current random access procedure, and performs a new random access procedure indicated by the RRC layer; or if the MAC layer continues the current random access procedure After the selection, the new random access procedure indicated by the RRC layer is performed.

 The confirmation module further includes:

 Confirmation module one 7011, used to confirm that the preamble sending counter reaches the maximum number of transmissions plus

After 1 , the MAC layer sends a random access problem indication to the RRC layer.

 The processing module is further configured to: if the MAC layer stops the current random access procedure, reset the value of the preamble sending counter and the backoff;

The processing module is further configured to: if the random access process is a competitive mode, clear the message 3 buffer.

 The processing module is further configured to: after receiving the RRC connection reestablishment indication sent by the RRC layer, trigger a new random access procedure in which the MAC layer initiates an RRC connection reestablishment indication.

 When the MAC layer enters the random access failure mode, if the MAC layer stops the current random access procedure, the MAC layer performs a new random access procedure indicated by the RRC layer; if the MAC layer continues the current random access procedure, the MAC selection is performed by the RRC. The layer indicates the new random access procedure. The random access procedure caused by the RRC connection reestablishment is guaranteed to have a higher priority, and the current random access procedure of the MAC layer and the new random access procedure caused by the RRC connection reestablishment are avoided, thereby avoiding random access resources. When the MAC layer enters the random access failure mode, if the MAC layer stops the current random access procedure,

The MAC layer performs a new random access procedure indicated by the RRC layer; if the MAC layer continues the current random access procedure, the MAC chooses to perform a new random access procedure indicated by the RRC layer. It is ensured that the random access procedure caused by the RRC connection reestablishment has a higher priority, avoiding the competition between the current random access procedure of the MAC layer and the new random access procedure caused by the RRC connection reestablishment, thereby avoiding waste of random access resources. .

 Through the description of the above embodiments, those skilled in the art can clearly understand that the present invention can be implemented by means of software and a necessary general hardware platform. Of course, hardware can also be used, but in many cases, the former is better. An embodiment. 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, including a plurality of instructions for causing a A computer device (which may be a personal computer, server, or network device, etc.) performs the method of various embodiments of the present invention.

 Although the invention has been illustrated and described with reference to the preferred embodiments of the present invention, it will be understood The spirit and scope of the invention.

Claims

Rights request  A method for processing a random access process, which is characterized by comprising:  Media access control The MAC layer enters a random access failure mode;  If the MAC layer stops the current random access procedure, the MAC layer performs a new random access procedure indicated by the radio resource control RRC layer;  If the MAC layer continues the current random access procedure, the MAC layer selects and performs a new random access procedure indicated by the RRC layer.  The method according to claim 1, wherein after the MAC layer enters the random access failure mode, the method further includes:  The MAC layer resets the access preamble. After the preamble transmission counter reaches the maximum number of transmissions plus one, the MAC layer sends a random access problem indication to the RRC layer.  The method according to claim 1 or 2, wherein, after the MAC layer stops the current random access procedure, the method further includes:  The MAC layer resets the value of the backoff of the preamble transmission counter and the maximum time interval of the random access of the MAC layer twice.  The method according to claim 3, wherein if the random access mode is a competitive mode, the method further includes:  MAC layer clear message 3 buffer.  The method according to claim 1 or 2, wherein, after the media access control MAC layer enters the random access failure mode, the method further includes:  The MAC layer receives the RRC connection reestablishment indication sent by the RRC layer, and triggers the MAC layer to initiate a new random access procedure of the RRC connection reestablishment indication.  A processing device for a random access process, comprising:  a confirmation module, configured to confirm that the MAC layer enters a random access failure mode;  a processing module, after the MAC layer enters the random access failure mode, the MAC layer stops the current random access procedure, and performs a new random access procedure indicated by the RRC layer; if the MAC layer continues the current random access procedure, the selection is performed A new random access procedure indicated by the RRC layer. The device according to claim 6, wherein the confirmation module further comprises: an acknowledgment module 1, configured to confirm that the preamble transmission counter reaches a maximum number of transmissions plus one, The MAC layer sends a random access problem indication to the RRC layer.  8. Apparatus according to claim 6 or claim 7 wherein:  The processing module is further configured to reset the preamble sending counter and the backoff value if the MAC layer stops the current random access procedure.  9. Apparatus according to claim 8 wherein:  The processing module is further configured to clear the message 3 buffer if the random access procedure is a contention mode. 10. Apparatus according to claim 6 wherein:  The processing module is further configured to: after receiving the RRC connection reestablishment indication sent by the RRC layer, trigger a new random access procedure in which the MAC layer initiates an RRC connection reestablishment indication.