Partitioning of Random Access Preambles

Patent metadata

Field	Value
Publication number	US-2020245362-A1
Application number	US-201816611511-A
Country	US
Kind code	A1
Filing date	May 15, 2018
Priority date	May 17, 2017
Publication date	Jul 30, 2020
Grant date	—

Abstract

The invention refers to a method at a user equipment for performing a random access procedure, wherein the UE randomly selects a random access preamble from a given set of preambles to be used for the random access procedure, the method comprising the steps of detecting ( 420 ) a partitioning of the given set of random access preambles into a first and a second partition, detecting ( 430 ) a certain capability of the UE, and selecting ( 440 ) a random access preamble from the fist partition to indicate the certain capability to a base station; the invention further refers to a corresponding method in a base station, a corresponding UE, and a corresponding base station.

First claim

1 - 23 . (canceled)

24 . A method at a user equipment (UE) for performing a random access procedure with a base station, wherein the UE is expected, if the UE does not have a certain capability, to randomly select a random access preamble from a given set of preambles to be used for the random access procedure, the method comprising the UE:
detecting a partitioning of the given set of random access preambles into a first and a second partition; detecting a certain capability of the UE; and in response to detecting the certain capability, selecting a random access preamble from the first partition to indicate the certain capability to the base station.

25 . The method of claim 24 , further comprising:
receiving system information from the base station; and detecting the partitioning from the system information.

26 . The method of claim 25 , wherein the system information comprises an information element indicative of the partitioning of a random access preamble space.

27 . The method of claim 26 , wherein the information element is an information element comprised by a Physical Random Access Channel (PRACH) configuration or a Narrowband PRACH (NPRACH) configuration.

28 . The method of claim 24 , wherein the certain capability is a capability to transmit or receive data before a radio resource control (RRC) connection setup or resume has been completed.

29 . The method of claim 24 , further comprising sending a message indicative of the selected random access preamble to the base station.

30 . The method of claim 29 , wherein the UE, receives a random access response in response to sending the message indicative of the selected random access preamble.

31 . The method of claim 30 , wherein the random access response comprises a dual grant in the random access response.

32 . The method of claim 30 , wherein the random access response comprises a larger uplink grant than that granted to UEs that do not have the certain capability.

33 . The method of claim 30 , wherein the UE receives a plurality of subsequent grants without explicitly requesting such grants.

34 . A user equipment (UE) configured to communicate with a base station for performing a random access procedure with a base station, wherein the UE is expected, if the UE does not have a certain capability, to randomly select a random access preamble from a given set of preambles to be used for the random access procedure the UE comprising:
processing circuitry; memory containing instructions executable by the processing circuitry whereby the UE is operative to:
detect a partitioning of the given set of random access preambles into a first and a second partition;
detect a certain capability of the UE; and
in response to detecting the certain capability, select a random access preamble from the first partition to indicate the certain capability to the base station.

35 . A method at a base station for performing a random access procedure, the method comprising the base station:
providing, to a User Equipment (UE), an indication of a partitioning of the given set of random access preambles into a first and a second partition, thereby expecting that the UE, if the UE has a certain capability, selects a random access preamble from the first partition, and otherwise that the UE randomly selects a random access preamble from the given set of preambles; receiving, from the UE, a message indicative of a selected random access preamble; assuming the certain capability of the UE by detecting that the selected random access preamble is comprised by the first partition although the base station does not know whether the UE has the certain capability or not.

36 . The method of claim 35 , further comprising sending system information comprising the indication of the partitioning.

37 . The method of claim 35 , wherein the system information comprises an information element indicative of the partitioning of a random access preamble space.

38 . The method of claim 37 , wherein the information element is an information element comprised by a Physical Random Access Channel (PRACH) configuration or a Narrowband PRACH (NPRACH) configuration.

39 . The method of claim 35 , wherein the certain capability is a capability to transmit or receive data before a radio resource control (RRC) connection setup or resume has been completed.

40 . The method of claim 39 , wherein the base station sends a random access response in response to receiving the message indicative of the selected random access preamble.

41 . The method of claim 40 , wherein the random access response comprises a dual grant in the random access response.

42 . The method of claim 40 , wherein the random access response comprises a larger uplink grant than that granted to UEs that do not have the certain capability.

43 . A base station, comprising:
processing circuitry; memory containing instructions executable by the processing circuitry whereby the base station is operative to:
provide, to a User Equipment (UE), an indication of a partitioning of the given set of random access preambles into a first and a second partition, thereby expecting that the UE, if the UE has a certain capability, selects a random access preamble from the first partition, and otherwise that the UE randomly selects a random access preamble from the given set of preambles;
receive, from the UE, a message indicative of a selected random access preamble;
assume the certain capability of the UE by detecting that the selected random access preamble is comprised by the first partition although the base station does not know whether the UE has the certain capability or not.

Assignees

• Ericsson Telefon Ab L M

Inventors

• Höglund Andreas
• Liberg Olof
• Tirronen Tuomas

Classifications

• H04W76/27 Primary

  Transitions between radio resource control [RRC] states · CPC title

• H04W72/23

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04W74/0838

  using contention-free random access [CFRA] · CPC title

• H04W74/0833 Primary

  Random access procedures, e.g. with 4-step access · CPC title

• H04W8/24

  Transfer of terminal data · CPC title