Interference control method for random access, device, and system

Patent metadata

Field	Value
Publication number	US-2016308635-A1
Application number	US-201615192626-A
Country	US
Kind code	A1
Filing date	Jun 24, 2016
Priority date	Dec 26, 2013
Publication date	Oct 20, 2016
Grant date	—

Abstract

The present invention belongs to the field of communications technologies, and discloses an interference control method for random access, device, and system. The method includes: acquiring a primary scrambling code of a random access preamble broadcast by a radio network controller; acquiring a random access preamble sent by user equipment UE; identifying, according to the primary scrambling code of the broadcast random access preamble and the random access preamble that is sent by the UE, that the UE is UE that camps on a first base station; and delivering an acquisition indication channel to the UE, to indicate whether the UE can perform uplink access. In the present invention, a second base station of a neighboring cell of a first base station delivers an acquisition indication channel to the UE, to indicate that the UE performs uplink access to the second base station.

First claim

What is claimed is:

1 . An interference control method for random access, the method comprising:
acquiring a primary scrambling code of a random access preamble broadcast by a radio network controller; acquiring a random access preamble sent by user equipment (UE); identifying, according to the primary scrambling code of the broadcast random access preamble and the random access preamble that is sent by the UE, that the UE is UE that camps on a first base station that serves a neighboring cell first base station that serves a neighboring cell; and delivering an acquisition indication channel to the UE, to indicate whether the UE can perform uplink access.

2 . The method according to claim 1 , wherein before acquiring a random access preamble sent by UE, the method further comprises:
receiving the random access preamble sent by the UE.

3 . The method according to claim 2 , wherein delivering an acquisition indication channel to the UE, to indicate whether the UE can perform uplink access comprises:
sending the acquisition indication channel to the UE, wherein a slot format of the acquisition indication channel comprises an acquisition indicator (AI) part, and the AI part uses a signature sequence corresponding to a signature sequence of the random access preamble sent by the UE, so that when detecting that the signature sequence of the AI corresponds to the signature sequence of the random access preamble, the UE decodes the signature sequence of the AI, and determines, according to a decoding result, whether uplink access is allowed.

4 . The method according to claim 1 , wherein before acquiring a random access preamble sent by UE, the method further comprises:
receiving the random access preamble sent by the UE; or listening to a random access preamble sent by the UE to the first base station.

5 . The method according to claim 4 , wherein delivering an acquisition indication channel to the UE, to indicate whether the UE can perform uplink access comprises:
estimating a remaining resource; and if there is a remaining resource, delivering the acquisition indication channel to the UE, wherein a slot structure of the acquisition indication channel comprises an AI part, and a parameter value indicating whether to allow the UE to perform uplink access is set in the AI part.

6 . The method according to claim 1 , wherein delivering an acquisition indication channel to the UE comprises:
repeatedly sending the acquisition indication channel by using multiple slots or transmission time intervals.

7 . The method according to claim 1 , further comprising:
receiving a random access message sent by the UE; and forwarding the random access message to a radio network controller, so that the radio network controller controls the first base station to send a forward access channel or a high-speed downlink shared channel to the UE.

8 . The method according to claim 7 , wherein forwarding the random access message to a radio network controller comprises:
identifying the random access message, and if the first base station is a sending target of the random access message, sending an uplink to the radio network controller according to the random access message.

9 . The method according to claim 8 , wherein identifying the random access message comprises:
determining, according to a scrambling code used in the random access message sent by the UE, the sending target of the random access message sent by the UE; or determining the sending target of the random access message according to indication information of a control part of the random access message sent by the UE.

10 . An interference control method for random access, the method comprising:
sending a random access preamble, so that a second base station acquires the random access preamble, wherein the second base station is a base station of a neighboring cell of a cell of a first base station on which UE camps; receiving an acquisition indication channel delivered by the second base station; and determining, according to an indication of the acquisition indication channel delivered by the second base station, whether the second base station allows uplink access, and if uplink access is allowed, sending a random access message to the second base station.

11 . The method according to claim 10 , wherein:
before sending a random access preamble, the method further comprises:
receiving a preamble signature sequence, a scrambling code, and an acquisition indication channel of the second base station that are broadcast by a radio network controller, and learning that a configuration of the first base station is that the UE is allowed to perform uplink access to the second base station, and
detecting that downlink channel quality of the second base station is greater than an uplink access threshold; and
sending a random access preamble, so that a second base station acquires the random access preamble comprises:
sending the random access preamble to the second base station by using the broadcast preamble signature sequence and scrambling code of the second base station, so that the second base station decodes the random access preamble, and identifies, according to the random access preamble, that the UE is UE that camps on a neighboring cell, so as to deliver the acquisition indication channel to the UE.

12 . The method according to claim 11 , wherein detecting that downlink channel quality of the second base station is greater than an uplink access threshold comprises:
acquiring related parameters, wherein the related parameters comprise M —new , CIO new , M best , and R RACH ; and determining, according to the related parameters, whether a formula 10 log M —new +CIO new ≧10 log M best +R RACH is true, and if the formula is true, confirming that the downlink channel quality of the second base station is greater than the uplink access threshold, wherein M —new is the downlink channel quality of the second base station; M —new is one or a combination of more of the following second base station parameters: a common pilot channel received signal code power CPICH_RSCP, a chip power noise ratio E c /N o , channel quality of a control channel, and channel quality of a synchronization channel; CIO —new is a measurement value offset of a cell of the second base station; M —best is channel quality of the cell of the first base station; and R RACH is a measurement report range.

13 . The method according to claim 10 , wherein determining, according to an indication of the acquisition indication channel delivered by the second base station, whether the second base station allows uplink access comprises:
detecting that a signature sequence of the acquisition indication channel delivered by the second base station corresponds to the signature sequence of the random access preamble, decoding the signature sequence of the acquisition indication channel, and determining, according to a decoding result, whether the second base station allows uplink access.

14 . The method according to claim 10 , wherein sending a random access message to the second base station comprises:
sending the random access message to the second base station by using the scrambling code and a spreading code of the second base station, wherein the spreading code is agreed upon in advance or acquired through broadcasting.

15 . The method according to claim 10 , wherein:
before sending a random access preamble, further the method further comprises:
receiving a scrambling code and an acquisition indication channel of the second base station that are

Assignees

• Huawei Tech Co Ltd

Inventors

• Zhou Han
• Hua Meng
• Tie Xiaolei

Classifications

• H04W74/0833

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

• H04W74/004 Primary

  in the uplink, i.e. towards network · CPC title

• H04J11/0053 Primary

  using co-ordinated multipoint transmission/reception (co-ordinated antenna or beam-forming aspects H04B7/022) · CPC title

• H04W52/04

  Transmission power control [TPC] · CPC title

• H04L1/20

  using signal quality detector · CPC title