Methods and apparatus for enhanced coexistence algorithms in wireless systems

• US 9,113,349 B2
• Filed: 12/21/2012
• Issued: 08/18/2015
• Est. Priority Date: 10/05/2009
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Tolentino, Jaime, Chen, Camille, Giles, Michael Jason, Le, Huy, Thomason, Gary, Hardell, David A.
• Primary Examiner(s): Milord, Marceau
• Application Number:
  US13/725,608
• Publication Number:
  US 20130182589A1
• Time in Patent Office: 970 Days
• Field of Search: 455/41.2, 455/63.1, 455/513, 455/553.1, 455/552.1, 370/338, 370/352, 370/252, 370/29, 370/329, 709/203, 375/285
• US Class Current: 1/1
• CPC Class Codes: H04B 15/00 Suppression or limitation of noise or interference by means associated with receiver H04B1/10
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04B 17/345 Interference values signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR] H04B17/336
• CPC Class Codes: H04L 1/0001 Systems modifying transmission characteristics according to link quality, e.g. power backoff adaptive data allocation for multicarrier modulation H04L5/0044; controlling transmission power for radio systems H04W52/04
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0012 Hopping in multicarrier systems for frequency hopping in spread spectrum systems H04B1/713
• CPC Class Codes: H04L 5/0066 Requirements on out-of-channel emissions
• CPC Class Codes: H04W 24/00 Supervisory, monitoring or testing arrangements
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 28/0236 radio quality, e.g. interference, losses or delay
• CPC Class Codes: H04W 28/04 Error control
• CPC Class Codes: H04W 4/80 Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication
• CPC Class Codes: H04W 52/245 taking into account received signal strength
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/1215 for collaboration of different radio technologies
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

Methods and apparatus for mitigating the effects of interference between multiple air interfaces located on an electronic device. In one embodiment, the air interfaces include a WLAN interface and PAN (e.g., Bluetooth) interface, and information such as Receiver Signal Strength Index (RSSI) as well as system noise level information are used in order to intelligently execute interference mitigation methodologies, including the selective application of modified frequency selection, variation of transmitter power, and/or change of operating mode (e.g., from multiple-in multiple-out (MIMO) to single-in, single-out (SISO)) so as to reduce isolation requirements between the interfaces. These methods and apparatus are particularly well suited to use cases where the WLAN interface is operating with high data transmission rates. Business methods associated with the foregoing technology are also described.

Claims

1. A wireless apparatus configured to reduce interference between at least two different wireless network interfaces, the apparatus comprising:

a first wireless network interface;

a second wireless network interface;

where the first and second wireless network interfaces are configured to operate in at least a partially overlapping frequency band;

a processor; and

a non-transitory computer-readable medium with at least one computer program stored thereon, the at least one computer program configured to, when executed on the processor, cause the wireless apparatus to;

determine a receiver signal strength index (RSSI) at the first wireless network interface;

determine a noise floor associated with the first wireless network interface; and

implement a coexistence algorithm with the second wireless network interface to reduce interference of the first wireless network interface based at least in part on the determined RSSI and determined noise floor.

2. The wireless apparatus of claim 1, wherein the coexistence algorithm is configured to adjust a frequency utilization of the second wireless network interface.

3. The wireless apparatus of claim 1, wherein the coexistence algorithm is configured to adjust a transmitter power of the second wireless network interface.

4. The wireless apparatus of claim 1, wherein the coexistence algorithm is configured to impose a data rate mask or limitation on the second wireless network interface.

5. A wireless apparatus configured to reduce interference between at least two different wireless network interfaces, the apparatus comprising:

a first wireless network interface;

a second wireless network interface, the first and second wireless network interfaces configured to operate in at least a partially overlapping frequency band;

a processor; and

a non-transitory computer-readable medium with at least one computer program stored thereon, the at least one computer program configured to, when executed on the processor, cause the wireless apparatus to;

determine a receiver signal strength index (RSSI) at the first wireless network interface and based on the determined RSSI, select one of at least two different frequency use maps; and

determine a noise value associated with the wireless apparatus and based on the determined noise value, select one of a plurality of operating modes of operation of the second wireless network interface;

where the selected mode is configured to adjust the transmit power of the second wireless network interface.

6. A wireless apparatus configured to operate a first and second air interfaces so as to mitigate interference therebetween without imposing time-sharing restrictions on either of the interfaces, the wireless apparatus comprising:

a first wireless interface;

a second wireless interface;

a processor; and

computerized logic configured to cause the wireless apparatus to;

determine a received signal strength using at least one of the first and second wireless interfaces;

determine a noise parameter using at least one of the first and second wireless interfaces; and

based on the determined received signal strength and noise parameter, selectively implement a frequency use mapping for the first wireless interface that substantially avoids one or more emitted sidebands associated with transmission from the second wireless interface.

7. A wireless apparatus configured to reduce interference between at least two different air interfaces, the apparatus comprising:

a first air interface;

a second air interface;

a processor; and

a computer-readable medium with at least one computer program stored thereon configured to, when executed on the processor, cause the wireless apparatus to;

determine a signal strength using at least one of the first and second air interfaces;

determine a system noise floor using at least one of the first and second air interfaces; and

implement a coexistence algorithm with the second air interface to reduce interference of the first air interface based at least in part on the determined signal strength and determined system noise floor.

8. The wireless apparatus of claim 7, wherein the coexistence algorithm is configured to adjust a frequency utilization of the second air interface.

9. The wireless apparatus of claim 7, wherein the coexistence algorithm is configured to adjust a transmitter power of the second air interface.

10. The wireless apparatus of claim 7, wherein the coexistence algorithm is configured to impose a data rate mask or limitation on the second air interface.

11. A wireless apparatus configured to operate a first and second air interfaces so as to mitigate interference there between without imposing time-sharing restrictions on either of the interfaces, the wireless apparatus comprising:

a first air interface;

a second air interface;

where the first and second air interfaces are configured to operate in at least a partially overlapping frequency band;

a processor; and

a non-transitory computer-readable medium with at least one computer program stored thereon, the at least one computer program configured to, when executed on the processor, cause the wireless apparatus to;

determine a receiver signal strength index (RSSI) at the first air interface;

determine a first noise floor associated with the first air interface;

determine a second noise floor associated with the first air interface; and

implement a coexistence algorithm with the second air interface to reduce interference of the first air interface based at least in part on the determined RSSI, determined first noise floor, and determined second noise floor.

12. The wireless apparatus of claim 11, wherein the coexistence algorithm is configured to implement an enhanced frequency hopping algorithm.

13. The wireless apparatus of claim 11, wherein the coexistence algorithm is configured to implement a transmission power mapping.

14. A wireless apparatus configured to reduce interference between at least two different air interfaces, the apparatus comprising:

a first wireless network interface;

a second wireless network interface, the first and second wireless network interfaces configured to operate in at least a partially overlapping frequency band;

a processor; and

computerized logic configured to cause the wireless apparatus to;

determine a received signal strength using at least one of the first and second wireless network interfaces;

determine a noise parameter using at least one of the first and second wireless network interfaces;

determine a first threshold value and a second threshold value; and

based on determining that the first and second wireless network interfaces satisfy an initial criterion, and based on comparing the first threshold value to the determined received signal strength and the second threshold value to the noise parameter, selectively implement a frequency use mapping for the first wireless network interface that substantially avoids one or more emitted sidebands associated with transmission from the second wireless network interface.

15. The wireless apparatus of claim 14, wherein the first and second threshold values are predetermined or dynamically determined.

16. The wireless apparatus of claim 15, wherein at least one of the threshold values is dynamically determined, and the act of determining the at least one of the thresholds comprises at least one of:

(i) requiring a periodic measurement of received signal strength, (ii) requiring a measurement of received signal strength during product development, (iii) estimating received signal strength, and (iv) correcting based on placement of the device with respect to other nearby radiators or using other equipment within the wireless apparatus.

17. The wireless apparatus of claim 14, wherein the initial criterion comprises at least one of:

(i) the first and second wireless network interfaces being compliant devices, (ii) the first and second wireless network interfaces operating in an overlapping spectrum, (iii) a RI peripheral device being connected, and (iv) a scheduled WLAN transmission occurring.

18. A wireless apparatus configured to reduce interference between at least two different air interfaces, the apparatus comprising:

a first wireless interface;

a second wireless interface;

a processor;

a non-transitory computer-readable medium with at least one computer program stored thereon, the at least one computer program configured to, when executed on the processor, cause the wireless apparatus to;

determine a receiver signal strength index (RSSI) at the first wireless interface;

determine a first noise floor associated with the first wireless interface;

determine a second noise floor associated with the first wireless interface;

determine a first, second, and third threshold value; and

based on comparing the first threshold value to the determined received signal strength and the second and third threshold values to the noise parameter, select one of a plurality of operating modes of operation of the second wireless interface;

wherein the selected mode is configured to adjust the transmit power of the second wireless interface.

19. The wireless apparatus of claim 18, wherein the first, second, and third threshold values are predetermined or dynamically determined.

20. The wireless apparatus of claim 19, wherein at least one of the threshold values is dynamically determined, and the act of determining the at least one of the thresholds comprises at least one of:

(i) requiring a periodic measurement of received signal strength, (ii) requiring a measurement of received signal strength during product development, (iii) estimating received signal strength, and (iv) correcting based on placement of the device with respect to other nearby radiators or using other equipment within the wireless apparatus.