PRE-ALLOCATED RANDOM ACCESS IDENTIFIERS

• US 20150359009A1
• Filed: 08/20/2015
• Published: 12/10/2015
• Est. Priority Date: 09/01/2006
• Status: Active Grant

• Current Assignee: Quarterhill Inc. (f/k/a Wi-LAN Inc.)
• Original Assignee: Wi-LAN Inc.
• Inventors: Bourlas, Yair, Newham, Adam E., Wang, Lei, Gummadi, Srikanth
• Granted Patent: US 9,226,320 B1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04B 7/2668 Arrangements for Wireless Code-Division Multiple Access [CDMA] System Synchronisation, for code acquisition H04B1/7075, for code tracking H04B1/7085
• CPC Class Codes: H04J 11/0073 Acquisition of primary synchronisation channel, e.g. detection of cell-ID within cell-ID group
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04L 5/0051 of dedicated pilots, i.e. pilots destined for a single user or terminal
• CPC Class Codes: H04W 36/0016 Hand-off preparation specially adapted for end-to-end data sessions
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 64/006 with additional information processing, e.g. for direction or speed determination
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/51 based on terminal or device properties
• CPC Class Codes: H04W 74/004 in the uplink, i.e. towards network
• CPC Class Codes: H04W 74/006 in the downlink, i.e. towards the terminal
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 74/085 collision avoidance
• CPC Class Codes: H04W 74/0875 with assigned priorities based access
• CPC Class Codes: H04W 74/0891 for synchronized access
• CPC Class Codes: H04W 76/28 Discontinuous transmission [DTX]; Discontinuous reception [DRX]
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/08 Access point devices

Abstract

Systems and methods of pre-allocating identifiers to wireless devices for use in requesting resources over a random access channel are described. A wireless communication system includes a random access channel over which wireless devices can anonymously send requests for resources. The base stations receiving and processing the anonymous requests reduces the probability of random access channel collisions and conserves the resources needed to support the anonymous requests by pre-allocating one or more identifiers to select wireless devices. The wireless devices having the pre-allocated codes can transmit a particular code over the random access channel as a request for resources that uniquely identifies the requester.

Claims

1. A method of operating a mobile station, comprising:

receiving, from a serving base station, an indication of a first reserved set of access identifiers usable for non-contention access over a first random access channel in a coverage area of the serving base station;

obtaining, during a handover of the mobile station from the serving base station to a target base station, an indication of a non-contention reserved access identifier identifying the mobile station in a coverage area of the target base station;

transmitting the non-contention reserved access identifier to the target base station over a second random access channel in the coverage area of the target base station;

receiving, from the target base station, a feedback message comprising a timing adjustment; and

adjusting at least one operating parameter of a transmission from the mobile station to the target base station based at least in part on the feedback message.

2. The method of claim 1, wherein the feedback message further comprises at least one of a power adjustment or a frequency offset adjustment.

3. The method of claim 1, wherein the non-contention reserved access identifier is from a second reserved set of access identifiers usable over the second random access channel in the coverage area of the target base station.

4. The method of claim 3, wherein the first reserved set of access identifiers is different from the second reserved set of access identifiers.

5. The method of claim 1, further comprising:

receiving, at the mobile station from the serving base station, an indication of a first non-contention reserved access identifier from the first reserved set of access identifiers, the first non-contention reserved access identifier identifying the mobile station in the coverage area of the serving base station.

6. The method of claim 5, wherein the first non-contention reserved access identifier is used for a specific type of request different from handover.

7. The method of claim 5, wherein the non-contention reserved access identifier identifying the mobile station in the coverage area of the target base station is different from the first non-contention reserved access identifier identifying the mobile station in the coverage area of the serving base station.

8. The method of claim 1, further comprising:

releasing the non-contention reserved access identifier subsequent to adjusting the at least one operating parameter of a transmission from the mobile station to the target base station.

9. The method of claim 1, wherein adjusting at least one operating parameter of a transmission from the mobile station to the target base station results in synchronizing the mobile to the target base station.

10. The method of claim 1, further comprising:

transmitting a bandwidth request message to the target base station subsequent to adjusting the at least one operating parameter of a transmission from the mobile station to the target base station.

11. The method of claim 1, wherein the non-contention reserved access identifier is a code division multiple access (CDMA) code.

12. A method of operating a mobile station, comprising:

receiving a message providing the mobile station with an indication of a non-contention reserved access identifier available for use by the mobile station in a coverage area of a target base station, the non-contention reserved access identifier belonging to a set of access identifiers reserved for non-contention access to the target base station;

receiving information about a shared random access channel available in the coverage area of the target base station;

transmitting the non-contention reserved access identifier to the target base station over the shared random access channel for handover;

receiving from the target base station a feedback message comprising a timing adjustment; and

adjusting uplink transmission timing of the mobile station using the timing adjustment.

13. The method of claim 12, wherein the feedback message further comprises a power adjustment or a frequency offset adjustment.

14. The method of claim 12, wherein the non-contention reserved access identifier is a code division multiple access (CDMA) code.

15. The method of claim 12, wherein the non-contention reserved access identifier uniquely identifies the mobile station in the coverage area of the target base station.

16. A mobile station comprising:

a receiver operable to receive, from a serving base station, an indication of a first reserved set of access identifiers usable for non-contention access over a first random access channel in a coverage area of the serving base station;

the receiver further operable to receive, during a handover of the mobile station from the serving base station to a target base station, an indication of a non-contention reserved access identifier identifying the mobile station in a coverage area of the target base station;

a transmitter operable to transmit the non-contention reserved access identifier to the target base station over a second random access channel in the coverage area of the target base station;

the receiver further operable to receive, from the target base station, a feedback message comprising a timing adjustment; and

a processor operable to adjust at least one operating parameter of a transmission from the mobile station to the target base station, the adjusting based at least in part on the feedback message.

17. The mobile station of claim 16, wherein the processor is further operable to release the non-contention reserved access identifier subsequent to adjusting the at least one operating parameter of a transmission from the mobile station to the target base station.

18. The mobile station of claim 16, wherein the non-contention reserved access identifier is a code division multiple access (CDMA) code.

19. The mobile station of claim 16, wherein the feedback message further comprises at least one of a power adjustment or a frequency offset adjustment.

20. The mobile station of claim 16, wherein the non-contention reserved access identifier is from a second reserved set of access identifiers usable over the second random access channel in the coverage area of the target base station.

21. The mobile station of claim 20, wherein the first reserved set of access identifiers is different from the second reserved set of access identifiers.

22. The mobile station of claim 16, wherein the receiver is further operable to receive from the serving base station an indication of a first non-contention reserved access identifier from the first reserved set of access identifiers, the first non-contention reserved access identifier identifying the mobile station in the coverage area of the serving base station.

23. The mobile station of claim 22, wherein the first non-contention reserved access identifier is used for a specific type of request different from handover.

24. The mobile station of claim 22, wherein the non-contention reserved access identifier identifying the mobile station in the coverage area of the target base station is different from the first non-contention reserved access identifier identifying the mobile station in a coverage area of the serving base station.

25. The mobile station of claim 16, wherein adjusting at least one operating parameter of a transmission from the mobile station to the target base station results in synchronizing the mobile station to the target base station.

26. The mobile station of claim 16, wherein the transmitter is further operable to transmit a bandwidth request message to the target base station subsequent to adjusting the at least one operating parameter of a transmission from the mobile station to the target base station.

27. A mobile station comprising:

a processor operable to;

receive a message providing an indication of a non-contention reserved access identifier available for use by the mobile station in a coverage area of a target base station, the non-contention reserved access identifier belonging to a set of access identifiers reserved for non-contention access to the target base station; and

receive information about a shared random access channel available in the coverage area of the target base station;

a transmitter operable to transmit the non-contention reserved access identifier to the target base station over the shared random access channel;

a receiver operable to receive from the target base station a feedback message comprising a timing adjustment; and

the processor further operable to adjust uplink transmission timing of the mobile station using the timing adjustment.

28. The mobile station of claim 27, wherein the feedback message further comprises a power adjustment or a frequency offset adjustment.

29. The mobile station of claim 27, wherein the non-contention reserved access identifier is a code division multiple access (CDMA) code.

30. The mobile station of claim 27, wherein the non-contention reserved access identifier uniquely identifies the mobile station in the coverage area of the target base station.