METHOD AND APPARATUS FOR COMMUNICATING IN A RELAY COMMUNICATION NETWORK

• US 20100103858A1
• Filed: 10/23/2008
• Published: 04/29/2010
• Est. Priority Date: 10/23/2008
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Palanki, Ravi, Agrawal, Avneesh
• Granted Patent: US 9,031,053 B2
• Time in Patent Office: Days
• US Class Current: 370/315
• CPC Class Codes: H04B 7/15507 Relay station based processing for cell extension or control of coverage area, network planning with network coordinated processing with regard to cell extension H04W16/26; network topologies using dedicated repeater stations H04W84/047; terminal devices adapted for relaying to or from an other terminal H04W88/04
• CPC Class Codes: H04B 7/15585 by interference cancellation
• CPC Class Codes: H04B 7/2606 Arrangements for base station coverage control, e.g. by using relays in tunnels
• CPC Class Codes: H04W 56/001 Synchronization between nodes

Abstract

Techniques for transmitting data in a relay communication network are described. In an aspect, stations in the relay network may be grouped into multiple depths, and stations at each depth may send the same transmission in each time interval. Packets may be transmitted in a pipelined manner in the relay network. Transmissions of a packet may be sent by stations at progressively higher depth in successive time intervals. A station may perform auto-configuration, attempt to decode transmissions from stations at different depths, and determine its depth based on decoding results. In another aspect, stations at each depth may transmit the same synchronization signal, and stations at different depths may transmit different synchronization signals. In one design, the synchronization signals for different depths may be different pilots, which may be generated with different scrambling codes or different orthogonal codes or may be multiplexed in frequency and/or time.

Claims

1. A method for wireless communication, comprising:

receiving at least one transmission in a first time interval from at least one station at a first depth in a relay communication network, the at least one transmission being received by a station at a second depth higher than the first depth; and

sending a transmission in a second time interval from the station, wherein stations at each depth send same transmission in each time interval.

2. The method of claim 1, wherein packets are transmitted in a pipeline in the relay network, and wherein transmissions of a packet are sent by stations at progressively higher depth in successive time intervals.

3. The method of claim 1, further comprising:

processing the at least one transmission to recover a packet from the at least one station at the first depth; and

generating the transmission for the station based on the recovered packet.

4. The method of claim 1, wherein the relay network comprises multiple depths including the first and second depths, and wherein stations at depth d are able to successfully decode transmissions from stations at depth d−

1 but not transmissions from stations at depth d−

2 or lower.

5. The method of claim 1, further comprising:

decoding transmissions received from stations at each of at least one depth; and

determining the second depth of the station based on decoding results.

6. The method of claim 1, further comprising:

decoding transmissions received from stations at depth d, where d is equal to a lowest depth initially;

decoding transmissions received from stations at next higher depth d+1 if the transmissions from the stations at depth d are unsuccessfully decoded; and

setting the second depth of the station to depth d+1 if the transmissions from the stations at depth d are successfully decoded.

7. The method of claim 1, further comprising:

receiving a first pilot from the at least one station at the first depth; and

transmitting a second pilot from the station, wherein stations at each depth transmit same pilot and stations at different depths transmit different pilots.

8. An apparatus for wireless communication, comprising:

at least one processor configured to receive at least one transmission in a first time interval from at least one station at a first depth in a relay communication network, the at least one transmission being received by a station at a second depth higher than the first depth, and to send a transmission in a second time interval from the station, wherein stations at each depth send same transmission in each time interval.

9. The apparatus of claim 8, wherein the at least one processor is configured to decode transmissions received from stations at depth d, where d is equal to a lowest depth initially, to decode transmissions received from stations at next higher depth d+1 if the transmissions from the stations at depth d are unsuccessfully decoded, and to set the second depth of the station to depth d+1 if the transmissions from the stations at depth d are successfully decoded.

10. The apparatus of claim 8, wherein the at least one processor is configured to receive a first pilot from the at least one station at the first depth, and to transmit a second pilot from the station, wherein stations at each depth transmit same pilot and stations at different depths transmit different pilots.

11. An apparatus for wireless communication, comprising:

means for receiving at least one transmission in a first time interval from at least one station at a first depth in a relay communication network, the at least one transmission being received by a station at a second depth higher than the first depth; and

means for sending a transmission in a second time interval from the station, wherein stations at each depth send same transmission in each time interval.

12. The apparatus of claim 11, further comprising:

means for decoding transmissions received from stations at depth d, where d is equal to a lowest depth initially;

means for decoding transmissions received from stations at next higher depth d+1 if the transmissions from the stations at depth d are unsuccessfully decoded; and

means for setting the second depth of the station to depth d+1 if the transmissions from the stations at depth d are successfully decoded.

13. The apparatus of claim 11, further comprising:

means for receiving a first pilot from the at least one station at the first depth; and

means for transmitting a second pilot from the station, wherein stations at each depth transmit same pilot and stations at different depths transmit different pilots.

14. A computer program product, comprising:

a computer-readable medium comprising;

code for causing at least one computer to receive at least one transmission in a first time interval from at least one station at a first depth in a relay communication network, the at least one transmission being received by a station at a second depth higher than the first depth, and

code for causing the at least one computer to send a transmission in a second time interval from the station, wherein stations at each depth send same transmission in each time interval.

15. A method for wireless communication, comprising:

receiving a first synchronization signal from at least one station at a first depth in a relay communication network; and

transmitting a second synchronization signal from a station at a second depth in the relay network, wherein stations at each depth transmit same synchronization signal.

16. The method of claim 15, wherein the first and second synchronization signals comprise first and second pilots, respectively, generated with different scrambling codes or different orthogonal codes.

17. The method of claim 15, wherein the first and second synchronization signals comprise first and second pilots, respectively, multiplexed in frequency or time.

18. The method of claim 15, further comprising:

obtaining timing information for the at least one station at the first depth based on the first synchronization signal.

19. The method of claim 15, further comprising:

determining the first depth of the at least one station based on the first synchronization signal.

20. The method of claim 15, further comprising:

receiving at least one transmission of a packet from the at least one station at the first depth;

deriving a channel estimate for the at least one station based on the first synchronization signal; and

processing the at least one transmission based on the channel estimate to recover the packet from the at least one station.

21. The method of claim 15, further comprising:

receiving a third synchronization signal from at least one station at a third depth in the relay network;

identifying the at least one station at the first depth based on the first synchronization signal; and

identifying the at least one station at the third depth based on the third synchronization signal.

22. An apparatus for wireless communication, comprising:

at least one processor configured to receive a first synchronization signal from at least one station at a first depth in a relay communication network, and to transmit a second synchronization signal from a station at a second depth in the relay network, wherein stations at each depth transmit same synchronization signal.

23. The apparatus of claim 22, wherein the first and second synchronization signals comprise first and second pilots, respectively, generated with different scrambling codes or different orthogonal codes.

24. A method for wireless communication, comprising:

receiving transmissions of packets in first frames from at least one station at a first depth in a relay communication network; and

sending transmissions of packets in second frames from a station at a second depth higher than the first depth, the second frames being non-overlapping with the first frames, and wherein a station at a lowest depth in the relay network sends transmissions of packets in both the first and second frames.

25. The method of claim 24, wherein a station at a highest depth in the relay network receives transmissions of packets in both the first and second frames.

26. The method of claim 24, wherein the relay network comprises multiple depths including the first and second depths, wherein stations at odd depths receive transmissions in the first frames and send transmissions in the second frames, and wherein stations at even depths receive transmissions in the second frames and send transmissions in the first frames.

27. The method of claim 24, wherein a first set of stations at the first depth send transmissions in the first frames and receive transmissions in the second frames, and wherein a second set of stations at the first depth send transmissions in the second frames and receive transmissions in the first frames.

28. The method of claim 24, wherein the first frames are even-numbered frames and the second frames are odd-numbered frames, or vice versa.

29. An apparatus for wireless communication, comprising:

at least one processor configured to receive transmissions of packets in first frames from at least one station at a first depth in a relay communication network, and to send transmissions of packets in second frames from a station at a second depth higher than the first depth, the second frames being non-overlapping with the first frames, and wherein a station at a lowest depth in the relay network sends transmissions of packets in both the first and second frames.

30. The apparatus of claim 29, wherein a station at a highest depth in the relay network receives transmissions of packets in both the first and second frames.

31. The apparatus of claim 29, wherein the relay network comprises multiple depths including the first and second depths, wherein stations at odd depths receive transmissions in the first frames and send transmissions in the second frames, and wherein stations at even depths receive transmissions in the second frames and send transmissions in the first frames.

32. The apparatus of claim 29, wherein a first set of stations at the first depth send transmissions in the first frames and receive transmissions in the second frames, and wherein a second set of stations at the first depth send transmissions in the second frames and receive transmissions in the first frames.