WO2019019770A1

WO2019019770A1 - Initial access method and apparatus of wireless terminal

Info

Publication number: WO2019019770A1
Application number: PCT/CN2018/086333
Authority: WO
Inventors: 高明刚; 倪庆瑜; 丁雪梅; 孙红利
Original assignee: 西安中兴新软件有限责任公司
Priority date: 2017-07-25
Filing date: 2018-05-10
Publication date: 2019-01-31
Also published as: CN109547993A

Abstract

An initial access method of a wireless terminal, comprising: marking, according to an urgent service attribute in a user request, the user request as an urgent service request in a radio resource control (RRC) layer; marking the user request as the urgent service request in a message sent to an intermediate layer; and notifying a physical layer to initiate an urgent initial access request.

Description

Method and device for initial access of wireless terminal

Technical field

The present disclosure relates to, but is not limited to, the field of Internet of Things technology, and in particular, a method and apparatus for initial access of a wireless terminal.

Background technique

From the perspective of the demand of 5G (fifth generation mobile communication technology), it generally includes three directions: the direction of large throughput is eMBB (Enhance Mobile Broadband), which is mainly for 5G mobile phone user terminals; ultra low latency The high reliability direction is uRLLC (Ultra-reliable and low latency communications), which is generally oriented to 5G emergency services or public safety, auto network driving, and industry 4.0 direction.

Summary of the invention

The following is an overview of the topics detailed in this document. This Summary is not intended to limit the scope of the claims.

In the ultra-low latency and high reliability direction of uRLLC, a particularly reliable and especially low-latency communication means is needed, so that it is necessary to consider how to improve the efficiency of communication establishment and reduce the time delay of communication establishment.

In the initial access of wireless communication, the initial access can be completed by using random access technology. The initial random access can be stepped up by power, randomly selecting the preamble, and competing for access.

In the random access process, the terminal can initially transmit a request to the base station with a small transmission power. When the base station does not respond, the terminal can add a little bit of power again and try to access again, which will undoubtedly introduce a time delay of initial access. This is not sufficient for products that require high reliability and ultra-low access latency.

After the initial preamble request is received, because it is a contention access, the network is also required to assist in the process of contention resolution, but because different UEs (user equipments) may randomly select the preamble when randomly selecting the preamble, such a network You can have the final decision to decide who wins. Since the network is unable to determine which terminal's request is more urgent, then the ruling can only be averaged with equal probability. A real emergency communication request may be delayed.

For an emergency request that can only be reflected in the RRC/NAS (Radio Resource Control, Network Attached Storage) message, trigger the initial random access procedure for establishing an RRC/NAS connection urgently, MAC (media) Interventional control and the physical layer are incapable of distinguishing whether they are urgent access requests, resulting in the same probability and delay in preempting resources at the bottom, even for emergency services and regular services.

When the terminal and the network establish emergency communication, only the NAS and RRC layers can expedite the express, and after RLC (Radio Link Control) and its physical layer, it is the same as the regular communication request. Way, can't distinguish. That is, there is no green channel on the bottom layer.

The present disclosure provides a method and apparatus for initial access of a wireless terminal, achieving a better timing and a higher initial power in a random access procedure in an emergency demand.

An embodiment of the present disclosure provides a method for initial access of a wireless terminal, which is applied to a terminal, and includes:

Marking the user request as an emergency service request in a radio resource control RRC layer according to an emergency service attribute requested by the user;

Marking the user request as an emergency service request in a message sent to the middle tier;

Notify the physical layer to initiate an emergency initial access request.

In an exemplary embodiment, the intermediate layer includes: a radio link control RLC layer and a media intervention control MAC layer.

In an exemplary embodiment, marking the user request for an emergency service request in a message sent to the middle tier includes:

When the packet data convergence protocol PDCP layer performs data encoding and packing, marking the user request as an emergency service request in a packet data convergence protocol data unit PDCP PDU message; and transmitting the PDCP PDU message to the RLC layer;

The RLC layer checks the PDCP PDU message, determines that the user requests an emergency service request, marks the user request as an emergency service request in a radio link control protocol data unit RLC PDU message, and sends the RLC PDU message to MAC layer;

The MAC layer checks the RLC PDU message to determine that the user request is an emergency service request.

In an exemplary embodiment, after the notifying the physical layer to initiate the emergency initial access request, the method further includes: performing preamble transmission by using a preset initial transmit power.

In an exemplary embodiment, obtaining the preset initial transmit power includes:

Calculating a sum of a random access request power value and an initial power boost value of the emergency initial access request;

Comparing the calculation result with the maximum transmit power of the terminal;

The minimum value obtained by comparison is taken as the initial transmission power.

The embodiment of the present disclosure further provides an apparatus for initial access of a wireless terminal, which is disposed on the terminal, and includes:

a marking module, configured to mark the user request as an emergency service request in a radio resource control RRC layer according to an emergency service attribute requested by the user;

a processing module, configured to mark the user request as an emergency service request in a message sent to the middle tier;

The access module is configured to notify the physical layer to initiate an emergency initial access request.

In an exemplary embodiment, the processing module marking the user request for an emergency service request in a message sent to the middle layer includes:

In an exemplary embodiment, the apparatus for initial access further includes: a sending module, configured to perform preamble transmission by using a preset initial transmit power.

In an exemplary embodiment, the obtaining, by the sending module, the preset initial transmit power includes:

Embodiments of the present disclosure also provide a computer readable storage medium storing computer executable instructions that, when executed, implement a method of initial access by a wireless terminal.

The present disclosure has the following beneficial effects:

The technical solution of the present disclosure distinguishes between an emergency service request and a regular service request at the bottom layer, avoids the emergency initial communication establishment caused by the initial low power of the PRACH to be repeatedly delayed, improves the efficiency of communication establishment, reduces the time delay of communication establishment, and improves the initial One-time success rate of access. For terminals with urgent communication needs, better timing and higher initial power can be obtained during the random access process. It avoids the invalid power loss caused by the multiple launch of PRACH power climbing, which can improve the battery life of the terminal, with good economy and high feasibility.

Other aspects will be apparent upon reading and understanding the drawings and detailed description.

BRIEF abstract

1 is a flowchart of a method for initial access of a wireless terminal according to an embodiment of the present disclosure;

2 is a schematic structural diagram of an apparatus for initial access of a wireless terminal according to an embodiment of the present disclosure;

3 is a flowchart of an initial access process of a vehicle networking platform terminal according to an alternative embodiment of the present disclosure;

4(a) is a schematic diagram of a packing structure of a PDCP PDU message in a 3GPP specification;

4(b) is a schematic diagram of a packing structure of a PDCP PDU message according to an optional embodiment of the present disclosure;

FIG. 5(a) is a schematic diagram of a RLC PDU message packing structure in a 3GPP specification;

FIG. 5(b) is a schematic diagram of a packet packing structure of an RLC PDU message according to an optional embodiment of the present disclosure.

Preferred embodiment of the present disclosure

Embodiments of the present disclosure will be described below with reference to the accompanying drawings.

As shown in FIG. 1 , an embodiment of the present disclosure provides a method for initial access of a wireless terminal, which is applied to a terminal, and may include:

S101. Mark the user request as an emergency service request in a radio resource control RRC layer according to an emergency service attribute requested by the user.

S102. Mark the user request as an emergency service request in a message sent to the middle layer.

S103. Inform the physical layer to initiate an emergency initial access request.

The intermediate layer may include: a radio link control RLC layer and a media intervention control MAC layer.

In the 3GPP (3rd Generation Partnership Project), the initial access uses a contention-based random access procedure, which can be implemented in a four-step process.

Msg1: performing random access preamble transmission by using a physical random access channel PRACH;

Msg2: performing a random access response by using a physical downlink shared channel PDSCH;

Msg3: A physical uplink shared channel PUSCH includes a C-RNTI (Cellular Radio Network Temporary Identity) MAC CE (Customer Edge) or a CCCH (Common Control Channel) SDU (Service Data Unit) Scheduled transmission;

Msg4: Resolve PDSCH collision using physical downlink shared channel.

In the contention-based random access procedure in the 3GPP, the emergency service request and the regular service request are distinguished in the RRC layer on the terminal side, and the emergency service is not distinguished in the PDCP (Packet Data Convergence Protocol) layer, the RLC layer, the MAC layer, and the physical layer. Request and regular service request, on the network side, because the underlying does not distinguish between emergency service request and regular service request, the emergency service request and the regular service request can be reflected at the RRC layer. Therefore, the probability and delay of the emergency service request in the underlying preemption resource The conventional service request method is the same; the method for initial access of the wireless terminal provided by the embodiment of the present disclosure distinguishes the emergency service request and the regular service request at the bottom layer, improves the efficiency of communication establishment, and reduces the time delay of communication establishment, and the terminal for emergency communication needs, Better timing and higher initial power can be obtained during the random access process.

The marking the user request for the emergency service request in the message sent to the middle layer in step S102 may include:

When the user requests emergency service, the RRC or NAS may be marked as an emergency service request, and an emergency service request is sent to the PDCP layer. When the PDCP layer performs data encoding and packing, the packet may be marked as an emergency service request in the packet header, and the PDCP PDU is sent (Protocol). The Data Unit (the protocol data unit) is sent to the RLC layer; when the RLC layer receives the PDCP SDU, it can check whether the emergency service request flag of the PDCP SDU header is indicated as an emergency service request, and synchronize the emergency service request when it is packaged as an RLC PDU. The flag bit is placed in the RLC's own packet header and sent to the MAC layer for processing. When the MAC layer receives the RLC SDU, it can decide whether it is an emergency access request according to the emergency service request flag bit in the RLC SDU packet header. If the emergency service request flag bit in the header of the RLC SDU is found to be an emergency service request, the physical layer may be notified to initiate an emergency initial access request; if the emergency service request flag bit in the header of the RLC SDU is found to be a regular service request, A regular initial access request can be sent.

After the step S103 is notified to the physical layer to initiate the emergency initial access request, the method may further include:

S104: Perform preamble transmission by using a preset initial transmit power.

Before step S104, the method may further include:

The minimum value obtained by comparison is taken as the preset initial transmission power.

After receiving the urgent initial access request transmitted by the MAC layer, the physical layer performs preamble transmission with an initial transmit power higher than the conventional calculated power.

As shown in FIG. 2, an embodiment of the present disclosure further provides an apparatus for initial access of a wireless terminal, where the apparatus is configured to be:

The processing module can be set to:

A transmitting module can also be included, configured to perform preamble transmission with a preset initial transmit power.

The sending module can also be configured as:

Alternative embodiment

Referring to FIG. 3, an initial access process of an emergency communication request based on the Internet of Vehicles platform is illustrated, which may include the following steps:

S300: In this embodiment, the user request is a vehicle network collision avoidance warning communication request, or an E911 call for help request. Optionally, when the user triggers an emergency service request, an alternative embodiment of the present disclosure is triggered.

S301: The RRC layer or the NAS layer may be marked by a certain means because the user triggers an emergency service request. For example, the RRC layer may mark Emergency Service as an emergency service request.

Among them, BIT STRING is a bit string; SIZE is a size.

At this time, because the RRC has been marked as emergency, when sent to the PDCP layer, an emergency service interaction primitive can be used to inform the PDCP layer to mark the user request for an emergency service request. For example, the service request primitive sent by the RRC layer to the PDCP layer is in the following format: in the service request sent by the RRC layer to the PDCP layer, an indication of whether it is an emergency service is added.

S302: After receiving the user request primitive of S301, the PDCP layer may indicate a specific header location as an emergency service request when packing the data. As shown in FIG. 4(a) and FIG. 4(b), respectively, the 3GPP existing PDCP layer packing structure includes three R (Reserved) bits, and one of the bits can be used as an extension. For example, using the first bit, it is marked as EMB (Emergency Bit).

After receiving the above service primitives, the EMB can be set to 1. At the time of packaging, the PDCP layer packets of the packet can be sent to the RLC for processing. As shown in FIG. 5(a) and FIG. 5(b), respectively, the existing 3GPP PDCP layer packing structure includes three R1 (Reserved) bits, and one of the bits can be used as an extension. For example, using the first bit, it is marked as EMB (Emergency Bit). (Note: If there is no Reserve bit in the specific RLC PDU header structure, the definition of other bits can be extended. This is just a specific case, and other extension methods for the packet header can also be used, and will not be described here.)

After receiving the above data packet, the EMB can be set to 1. At the time of packing, the packaged RLC layer data packet can be sent to the MAC layer for processing.

S303: After the MAC layer receives the RLC data packet, check the EMB bit. When the EMB bit is 1, send an emergency initial access request to the physical layer.

S304: After the physical layer receives the emergency initial access request, the normal initial transmit power may first be calculated according to methods known in the art. The conventional calculation method obtains the power P for transmitting the initial access request as:

P=preambleInitialReceivedTargetPower+DELTA_PREAMBLE+(PREAMBLE_TRANSMISSION_COUNTER–1)*powerRampingStep

The preambleInitialReceivedTargetPower is the initial power of the preamble that the eNodeB expects to receive. DELTA_PREAMBLE (preamble offset) is related to the preamble format (value), see Table 7.6-1 of 3GPP TS (Technical Specification) 36.321. The powerRampingStep is the transmit power boosted by the next access after each access failure.

Since it is an emergency communication request, a power offset can be added, and the power P' used by the terminal to send a random access request is:

P’=Min(Pmax,P+DeltaP)

Where Pmax is the maximum transmit power of the terminal and DeltaP is the initial power boost value for the emergency initial access request. The terminal then uses this power P' to send a random access request.

Embodiments of the present disclosure also provide a computer readable storage medium storing computer executable instructions that, when executed, implement a method of initial access by the wireless terminal.

Those of ordinary skill in the art will appreciate that all or some of the steps, systems, and functional blocks/units of the methods disclosed above may be implemented as software, firmware, hardware, and suitable combinations thereof. In a hardware implementation, the division between functional modules/units mentioned in the above description does not necessarily correspond to the division of physical components; for example, one physical component may have multiple functions, or one function or step may be composed of several physical The components work together. Some or all of the components may be implemented as software executed by a processor, such as a digital signal processor or microprocessor, or as hardware, or as an integrated circuit, such as an application specific integrated circuit. Such software may be distributed on a computer readable medium, which may include computer storage media (or non-transitory media) and communication media (or transitory media). As is well known to those of ordinary skill in the art, the term computer storage medium includes volatile and nonvolatile, implemented in any method or technology for storing information, such as computer readable instructions, data structures, program modules or other data. Sex, removable and non-removable media. The computer storage medium includes, but is not limited to, Random Access Memory (RAM), Read-Only Memory (ROM), and Electrically Erasable Programmable Read-only Memory (EEPROM). Flash memory or other memory technology, compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical disc storage, magnetic cassette, magnetic tape, disk storage or other magnetic storage device, or Any other medium used to store the desired information and that can be accessed by the computer. Moreover, it is well known to those skilled in the art that communication media typically includes computer readable instructions, data structures, program modules or other data in a modulated data signal, such as a carrier wave or other transport mechanism, and can include any information delivery media. .

A person skilled in the art can understand that the technical solutions of the present disclosure may be modified or equivalent, without departing from the spirit and scope of the present disclosure, and should be included in the scope of the claims of the present disclosure.

Industrial applicability

Claims

A method for initial access of a wireless terminal is applied to a terminal, including:

Marking the user request as an emergency service request in a radio resource control RRC layer according to an emergency service attribute requested by the user;

Marking the user request as an emergency service request in a message sent to the middle tier;

Notify the physical layer to initiate an emergency initial access request.
The method of initial access according to claim 1, wherein said intermediate layer comprises: a radio link control RLC layer and a media intervention control MAC layer.
The method of initial access according to claim 2, wherein: marking the user request for an emergency service request in a message sent to the middle layer comprises:

When the packet data convergence protocol PDCP layer performs data encoding and packing, marking the user request as an emergency service request in a packet data convergence protocol data unit PDCP PDU message; and transmitting the PDCP PDU message to the RLC layer;

The RLC layer checks the PDCP PDU message, determines that the user requests an emergency service request, marks the user request as an emergency service request in a radio link control protocol data unit RLC PDU message, and sends the RLC PDU message to MAC layer;

The MAC layer checks the RLC PDU message to determine that the user request is an emergency service request.
The initial access method of claim 1, after notifying the physical layer to initiate an emergency initial access request, further comprising: performing preamble transmission by using a preset initial transmit power.
The method of initial access according to claim 4, further comprising:

Calculating a sum of a random access request power value and an initial power boost value of the emergency initial access request;

Comparing the calculation result with the maximum transmit power of the terminal;

The minimum value obtained by the comparison is taken as the preset initial transmission power.
A device for initial access of a wireless terminal, configured on the terminal, includes:

a marking module, configured to mark the user request as an emergency service request in a radio resource control RRC layer according to an emergency service attribute requested by the user;

a processing module configured to mark the user request as an emergency service request in a message sent to the middle tier;

The access module is configured to notify the physical layer to initiate an emergency initial access request.
The apparatus of initial access according to claim 6, wherein: said intermediate layer comprises: a radio link control RLC layer and a media intervention control MAC layer.
The apparatus for initial access according to claim 7, wherein: said processing module is configured to:

When the packet data convergence protocol PDCP layer performs data encoding and packing, marking the user request as an emergency service request in a packet data convergence protocol data unit PDCP PDU message; and transmitting the PDCP PDU message to the RLC layer;

The RLC layer checks the PDCP PDU message, determines that the user requests an emergency service request, marks the user request as an emergency service request in a radio link control protocol data unit RLC PDU message, and sends the RLC PDU message to MAC layer;

The MAC layer checks the RLC PDU message to determine that the user request is an emergency service request.
The apparatus for initial access according to claim 6, further comprising: a sending module, configured to perform preamble transmission by using a preset initial transmit power.
The apparatus for initial access according to claim 6, wherein the sending module is further configured to:

Calculating a sum of a random access request power value and an initial power boost value of the emergency initial access request;

Comparing the calculation result with the maximum transmit power of the terminal;

The minimum value obtained by the comparison is taken as the preset initial transmission power.