Method and apparatus for interference management between networks sharing a frequency spectrum

Patent metadata

Field	Value
Publication number	US-9264907-B2
Application number	US-12326608-A
Country	US
Kind code	B2
Filing date	May 19, 2008
Priority date	Jul 10, 2007
Publication date	Feb 16, 2016
Grant date	Feb 16, 2016

Abstract

A method and system are provided that allows a wireless terminal to share an allocated frequency spectrum for communications over two different networks while mitigating cross interference. For wireless terminals equipped with a single antenna, interference mitigation may be achieved by allocating first communication channels to a first network and allocating second communication channels to a second network, wherein the second communication channels are allocated within one or more of the first communication channels. For wireless terminals having multiple antennas, interference mitigation may be achieved with two orthogonally polarized antennas, where each antenna is used for communications with a different network. Consequently, a wireless terminal having a channel allocation for communicating over the first wireless network may reuse the same channel allocation to establish a communication link with a second wireless terminal via a second wireless network using at least part of the channel allocation for the first wireless network.

First claim

What is claimed is:

1. A method for operating a wireless terminal equipped with at least a first antenna and a second antenna, the method comprising:
sensing signal strengths of a received signal on at least two polarizations;
discovering the polarization for the received signal based on the sensed signal strengths of the received signal on the at least two polarizations;
transmitting a first signal to a base station using the first antenna having a first polarization in a first direction, the first polarization based on the discovered polarization, wherein the base station provides wireless wide area network (WAN) connectivity to the wireless terminal;
transmitting a second signal to a second wireless terminal using the second antenna having a second polarization in a second direction, wherein the wireless terminal provides ad hoc peer-to-peer connectivity to the second wireless terminal, wherein said ad hoc peer-to-peer connectivity is established directly between the wireless terminal and the second wireless terminal free of call set-up via any network managing entity, and wherein said ad hoc peer-to-peer connectivity is established without routing a call via the base station; and
obtaining a channel allocation for communicating with the base station, wherein the channel allocation allocates at least one of a forward link timeslot and a reverse link timeslot for the wireless terminal and the second wireless terminal, wherein the first signal and the second signal are transmitted in a same frequency spectrum, wherein the first signal and the second signal are transmitted in overlapping time intervals, and wherein the second signal is transmitted within the allocated at least one of the forward link timeslot and the reverse link timeslot.

2. The method of claim 1 , wherein the first and the second signals are transmitted in non-overlapping time intervals.

3. The method of claim 1 , wherein the first signal is a wireless WAN signal and the second signal is a peer-to-peer signal.

4. The method of claim 1 , wherein the first and second polarizations are orthogonal with respect to each other.

5. The method of claim 1 , wherein the first and second polarizations are different by at least forty-five (45) degrees.

6. The method of claim 1 , wherein the first polarization is a horizontal polarization and the second polarization is a vertical polarization.

7. The method of claim 1 , wherein the first polarization is a first mix of horizontal and vertical polarizations and the second polarization is a second mix of vertical and horizontal polarizations.

8. The method of claim 1 , further comprising:
obtaining the channel allocation, wherein the first signal and second signal share the channel allocation.

9. The method claim 8 , wherein the channel allocation includes at least one of forward and reverse link timeslots, and forward and reverse link frequencies.

10. The method of claim 1 , further comprising:
obtaining the channel allocation for communicating with the base station, wherein the first signal is transmitted within the channel allocation and the second signal is transmitted using at least part of the channel allocation.

11. The method of claim 1 , further comprising:
ascertaining an orientation for the wireless terminal based on received signals of known polarization from the base station.

12. The method of claim 11 , further comprising:
beamforming using the first and second antennas to align transmission and reception for the wireless terminal with the received signals of known polarization from the base station.

13. The method of claim 1 , further comprising:
initiating a call with the second wireless terminal via the ad hoc peer-to-peer connectivity;
determining whether the second wireless terminal is within range of the wireless terminal; and
establishing the call with the second wireless terminal via the second antenna.

14. The method of claim 13 , wherein the call is established directly between the wireless terminal and the second wireless terminal via the ad hoc peer-to-peer connectivity free of call set-up via any base station.

15. The method of claim 1 , wherein transmissions via the first antenna have a higher power relative to lower power transmissions via the second antenna.

16. The method of claim 1 , wherein transmissions via the first antenna have a longer range relative to shorter range transmissions via the second antenna.

17. The method of claim 1 , wherein said ad hoc peer-to-peer connectivity occurs without routing communication via any base station.

18. The method of claim 1 , wherein said ad hoc peer-to-peer connectivity occurs without routing communication via any other transmitter.

19. The method of claim 1 , wherein said ad hoc peer-to-peer connectivity occurs directly between the wireless terminal and the second wireless terminal free of retransmission by any base station.

20. The method of claim 1 , wherein said ad hoc peer-to-peer connectivity is established directly between the wireless terminal and the second wireless terminal free of call set-up via any base station.

21. The method of claim 1 , further comprising:
receiving communication transmitted by the second wireless terminal via the ad hoc peer-to-peer connectivity.

22. The method of claim 21 , wherein the communication is received directly from the second wireless terminal.

23. The method of claim 1 , wherein the wireless terminal and the second wireless terminal do not have a common timing reference.

24. A wireless terminal, comprising:
a first antenna having a first polarization in a first direction;
a second antenna having a second polarization in a second direction;
a processing circuit coupled to the first and second antennas, the processing circuit further configured to:
sense signal strengths of a received signal on at least two polarizations;
discover the polarization for the received signal based on the sensed signal strengths of the received signal on the at least two polarizations;
transmit a first signal to a base station using the first antenna, the first polarization based on the discovered polarization, wherein the base station provides wireless wide area network (WAN) connectivity to the wireless terminal;
transmit a second signal to a second wireless terminal using the second antenna, wherein the wireless terminal provides ad hoc peer-to-peer connectivity to the second wireless terminal, wherein said ad hoc peer-to-peer connectivity is established directly between the wireless terminal and the second wireless terminal free of call set-up via any network managing entity, and wherein said ad hoc peer-to-peer connectivity is established without routing a call via the base station; and
obtain a channel allocation for communicating with the base station, wherein the channel allocation allocates at least one of a forward link timeslot and a reverse link timeslot for the wireless terminal and the second wireless terminal, wherein the first signal and the second signal are transmitted in a same frequency spectrum, wherein the first signal and the second signal are transmitted in overlapping time intervals, and wherein the second signal is transmitted within the allocated at least one of the forward link timeslot and the reverse link timeslot.

25. The terminal of claim 24 , wherein the first and the second signals are transmitted in non-overlapping time intervals.

26. The t

Assignees

• Laroia Rajiv
• Li Junyi
• Wu Xinzhou
• Qualcomm Inc

Inventors

• Laroia Rajiv
• Li Junyi
• Wu Xinzhou

Classifications

• H04W16/14

  Spectrum sharing arrangements {between different networks} · CPC title

• H04W16/12 Primary

  Fixed resource partitioning · CPC title