Methods and apparatus supporting multiple timing synchronizations corresponding to different communications peers

• US 8,385,317 B2
• Filed: 07/06/2007
• Issued: 02/26/2013
• Est. Priority Date: 07/06/2007
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Laroia, Rajiv, Li, Junyi, Jovicic, Aleksandar, Richardson, Thomas, Wu, Xinzhou
• Primary Examiner(s): FARAGALLA, MICHAEL A
• Application Number:
  US11/774,375
• Publication Number:
  US 20090010244A1
• Time in Patent Office: 2,062 Days
• Field of Search: 455/502, 455/101, 455/517, 455/522, 370/338, 370/252, 370/311, 370/329
• US Class Current: 370/350
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0032 Distributed allocation, i.e. involving a plurality of allocating devices, each making partial allocation
• CPC Class Codes: H04L 5/0044 allocation of payload
• CPC Class Codes: H04W 56/002 Mutual synchronization
• CPC Class Codes: H04W 92/18 between terminal devices

Abstract

Methods and apparatus related to peer to peer communication networks are described. A wireless communications device supports peer to peer communications with multiple peers. The wireless communications device determines its transmit timing synchronization based on a reference signal received from a node such as a base station, a satellite, or a beacon transmitter which does not transmit user data. The wireless communications device determines a plurality of different receive timing adjustments corresponding to different peer communications devices based on signals received from those peer communications devices. The wireless communications device stores the plurality of determined receive timing adjustment information corresponding to the different peer communications devices. The wireless communications device retrieves and applies stored receive timing adjustment information which matches the particular device which transmitted the signal attempting to be recovered.

Claims

1. A method of operating a first communications device to support communication with multiple peer communications devices including a second communications device and a third communications device, the method comprising:

receiving a signal from the second communications device;

performing a transmit timing synchronization operation based on a reference signal received from a non-peer fourth device to determine transmission symbol timing;

storing first receive timing adjustment information for adjusting receive symbol timing relative to said determined transmission symbol timing when communicating with said second communications device, generating said stored first receive timing adjustment information from said received signal;

storing second receive timing adjustment information for adjusting receive symbol timing relative to said determined transmission symbol timing when communicating with said third communications device, wherein the first and second receive timing adjustment information are stored separately

and

transmitting to said second and third communications devices using said determined transmission symbol timing.

2. The method of claim 1, wherein said received signal is one of a traffic signal sent from the second communications device to the first communications device and a traffic signal sent from the second communications device to another communications device.

3. The method of claim 1, further comprising:

prior to storing second receive timing adjustment information,

receiving a signal from the third communications device; and

generating said stored second receive timing adjustment information from said received signal from the third communications device.

4. The method of claim 1, wherein transmit timing is not adjusted based on signals received from said second and third communications devices.

5. A first communications device which support communication with multiple peer communications devices including a second communications device and a third communications device, the first communications device comprising:

a transmit timing synchronization module for performing a transmit timing synchronization operation based on a reference signal received from a non-peer fourth device to determine transmission symbol timing;

a receive timing adjustment information storage module

for storing first receive timing adjustment information for adjusting receive symbol timing relative to said determined transmission symbol timing when communicating with said second communications device; and

for storing second receive timing adjustment information for adjusting receive symbol timing relative to said determined transmission symbol timing when communicating with said third communications device;

wherein the first and second receive timing adjustment information are stored separately

a transmitter control module for controlling transmitting to said second and third communications devices using said determined transmission symbol timing

a wireless receiver module for receiving a signal from the second communications device; and

a receive timing adjustment information generation module for generating said stored first receive timing adjustment information from said received signal.

6. The first communications device of claim 5, wherein said received signal is one of a traffic signal sent from the second communications device to the first communications device and a traffic signal sent from the second communications device to another communications device.

7. The first communications device of claim 5,

wherein said wireless receiver module is also used to receive a signal from the third communications device;

and

wherein said receive timing adjustment information generation module is also used to generate said stored second receive timing adjustment information from said received signal from said third communications device.

8. The first communications device of claim 5, wherein transmit timing is not adjusted based on signals received from said second and third communications devices.

9. The first communications device of claim 7, further comprising:

a receive timing adjustment module for retrieving and applying stored receive timing adjustment information which matches the particular device which transmitted the signal attempting to be recovered.

10. A first communications device which support communication with multiple peer communications devices including a second communications device and a third communications device, the first communications device comprising:

transmit timing synchronization means for performing a transmit timing synchronization operation based on a reference signal received from a non-peer fourth device to determine transmission symbol timing;

receive timing adjustment information storage means

for storing first receive timing adjustment information for adjusting receive symbol timing relative to said determined transmission symbol timing when communicating with said second communications device; and

for storing second receive timing adjustment information for adjusting receive symbol timing relative to said determined transmission symbol timing when communicating with said third communications device, wherein the first and second receive timing adjustment information are stored separately

transmitter control means for controlling transmitting to said second and third communications devices using said determined transmission symbol timing

wireless receiver means for receiving a signal from the second communications device; and

means for generating said stored first receive timing adjustment information from said received signal.

11. The first communications device of claim 10, wherein said received signal is one of a traffic signal sent from the second communications device to the first communications device and a traffic signal sent from the second communications device to another communications device.

12. The first communications device of claim 10,

wherein said wireless receiver means is also used to receive a signal from the third communications device;

and

wherein said means for generating said stored first receive timing adjustment information is also used to generate said stored second receive timing adjustment information from said received signal from said third communications device.

13. The first communications device of claim 12, further comprising:

receive timing adjustment means for retrieving and applying stored receive timing adjustment information which matches the particular device which transmitted the signal attempting to be recovered.

14. A computer readable medium embodying machine executable instructions for operating a first communications device to implement a method of supporting communication with multiple peer communications devices including a second communications device and a third communications device, the method comprising:

performing a transmit timing synchronization operation based on a reference signal received from a non-peer fourth device to determine transmission symbol timing;

storing first receive timing adjustment information for adjusting receive symbol timing relative to said determined transmission symbol timing when communicating with said second communications device; and

storing second receive timing adjustment information for adjusting receive symbol timing relative to said determined transmission symbol timing when communicating with said third communications device, wherein the first and second receive timing adjustment information are stored separately;

transmitting to said second and third communications devices using said determined transmission symbol timing;

receiving a signal from the second communications device; and

generating said stored first receive timing adjustment information from said received signal.

15. The computer readable medium of claim 14, wherein said received signal is one of a traffic signal sent from the second communications device to the first communications device and a traffic signal sent from the second communications device to another communications device.

16. The computer readable medium of claim 14, further embodying machine executable instructions for:

prior to storing second receive timing adjustment information,

receiving a signal from the third communications device; and

generating said stored second receive timing adjustment information from said received signal from the third communications device.

17. The computer readable medium of claim 14, wherein transmit timing is not adjusted based on signals received from said second and third communications devices.

18. An apparatus comprising:

a processor to support communication with multiple peer communications devices including a second communications device and a third communications device, the processor configured to;

perform a transmit timing synchronization operation based on a reference signal received from a non-peer fourth device to determine transmission symbol timing;

store first receive timing adjustment information for adjusting receive symbol timing relative to said determined transmission symbol timing when communicating with said second communications device; and

store second receive timing adjustment information for adjusting receive symbol timing relative to said determined transmission symbol timing when communicating with said third communications device, wherein the first and second receive timing adjustment information are stored separately

transmit to said second and third communications devices using said determined transmission symbol timing and

prior to storing first receive timing adjustment information,

receive a signal from the second communications device; and

generate said stored first receive timing adjustment information from said received signal.

19. The apparatus of claim 18, wherein said received signal is one of a traffic signal sent from the second communications device to the first communications device and a traffic signal sent from the second communications device to another communications device.

20. The apparatus of claim 18, wherein said processor is further configured to:

prior to storing second receive timing adjustment information,

receive a signal from the third communications device; and

generate said stored second receive timing adjustment information from said received signal from the third communications device.

21. The apparatus of claim 18, wherein transmit timing is not adjusted based on signals received from said second and third communications devices.