Mitigating interference between wireless systems

• US 7,366,471 B1
• Filed: 08/31/2000
• Issued: 04/29/2008
• Est. Priority Date: 08/31/2000
• Status: Expired due to Term

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Kitchin, Duncan M.
• Primary Examiner(s): Nguyen; Lee
• Application Number:
  US09/652,697
• Time in Patent Office: 2,798 Days
• Field of Search: 455/63.1, 455/63.2, 455/63.3, 455/67.11, 455/67.13, 455/67.15, 455/41.2, 455/41.3
• US Class Current: 455/63.1
• CPC Class Codes: H04B 15/00 Suppression or limitation of noise or interference by means associated with receiver H04B1/10
• CPC Class Codes: H04W 16/14 Spectrum sharing arrangements between different networks
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/541 using the level of interference
• CPC Class Codes: H04W 92/20 between access points

Abstract

Two separate radio frequency networks may be operated within interference distance from one another in a way which mitigates the possibility of interference. Using received signal strength indicator data, the nature of the interference may be determined without actually demodulating the interfering signal. The timing of the interfering signal and its characteristic features may be determined. Using that information, together with the probability that any given slot will actually be occupied by an interfering transmission, a statistics package may be developed which gives an indication of the probability of a transmission from the interferer at any given time. That package may be transmitted to other nodes in the same network. When a first node wishes to transmit information to a second node, the first node may analyze the statistics package received from the second node. The first node may thereby make a determination about when to actually initiate the transmission to the second node.

Claims

1. A method comprising:

determining a characteristic of a local noise source affecting a first transceiver, said characteristic sufficient to enable prediction of the future behavior of the noise source;

determining the length of an intended transmission;

using said characteristic and said length to predict a time period when the effect of the local noise source would be reduced for sufficient time for said intended transmission.

2. The method of claim 1 wherein determining a characteristic includes determining a characteristic of a local noise source at a first network node and using said characteristic to control a wireless transmission from a second network node to said first network node.

3. The method of claim 1 wherein using said characteristic includes determining a probability of a transmission occurring at a given time from said local noise source.

4. The method of claim 3 including delaying a transmission from a second transceiver to said first transceiver until the probability of interference with said local noise source is reduced.

5. The method of claim 1 wherein using said characteristic includes identifying a characteristic of said local noise source without demodulating said local noise source.

6. The method of claim 5 wherein using said characteristic includes identifying a periodicity in said noise source without demodulating said noise source.

7. The method of claim 1 including receiving a statistical model of said noise source to enable prediction of the future behavior of said noise source.

8. The method of claim 1 including identifying information about the transmission slots of said local noise source.

9. The method of claim 8 including determining the start point of a sequence of slots.

10. The method of claim 9 including determining whether a particular slot is used for transmitting information.

11. The method of claim 10 including using information about whether a slot is occupied to predict a time period of less noise from said noise source.

12. An article comprising a medium storing instructions that, if executed, enable a processor-based system to:

determine a characteristic of a local noise source at a first transceiver, said characteristic sufficient to enable prediction of the future behavior of the noise source;

determine the length of an intended transmission;

use said characteristic of said noise source and said length to predict a time period when the effect of said local noise source on said first transceiver would be reduced for sufficient time for said intended transmission.

13. The article of claim 12 further storing instructions that enable the processor-based system to control a transmission from said second transceiver to reduce the probability of interference between said transmission and said local noise source.

14. The article of claim 12 further storing instructions that enable a processor-based system to transmit information about the probability of a transmission from said local noise source occurring at a given time.

15. The article of claim 12 further storing instructions to identify information about the transmission slots of said local noise source.

16. The article of claim 15 further storing instructions to determine the start point of a sequence of slots.

17. The article of claim 16 further storing instructions to determine whether a particular slot is used for transmitting information.

18. The method of claim 17 further storing instructions to use information about whether a slot is occupied to predict a time period of less noise from said noise source.

19. A transceiver comprising:

a unit to process information about a noise source and the length of an intended transmission, said characteristic sufficient to enable prediction of the future behavior of the noise source to analyze said noise source and to predict a time period when the effect of said noise source would be reduced for sufficient time for said intended transmission.

20. The transceiver of claim 19 wherein said transceiver is a network node.

21. The transceiver of claim 19 including a received signal strength indication detector coupled to said unit.

22. The transceiver of claim 19, said unit to identify information about the transmission slots of said local noise source.

23. The transceiver of claim 22, said unit to determine the start point of a sequence of slots.

24. The transceiver of claim 23, said unit to determine whether a particular slot is used for transmitting information.

25. The transceiver of claim 24, said unit to use information about whether a slot is occupied to predict a time period of less noise from said noise source.