Method and apparatus for an adaptive filter architecture

• US 8,781,044 B2
• Filed: 09/14/2012
• Issued: 07/15/2014
• Est. Priority Date: 11/11/2008
• Status: Active Grant

• Current Assignee: ISCO International LLC
• Original Assignee: ISCO International LLC
• Inventors: Abdelmonem, Amr, Cordone, Sean S.
• Primary Examiner(s): Liu, Shuwang
• Assistant Examiner(s): TAYONG, HELENE E
• Application Number:
  US13/617,703
• Publication Number:
  US 20130010627A1
• Time in Patent Office: 669 Days
• Field of Search: 375/346, 375/148, 375/335, 375/350, 375/206, 375/316, 370/335, 455/296, 455/278, 455/306, 327/310, 327/384, 327/551
• US Class Current: 375/350
• CPC Class Codes: H04B 1/1036 with automatic suppression of narrow band noise or interference, e.g. by using tuneable notch filters H04B1/123 takes precedence; filter circuits H03H
• CPC Class Codes: H04B 1/707 using direct sequence modulation
• CPC Class Codes: H04B 1/7093 Matched filter type
• CPC Class Codes: H04B 1/7103 the interference being multiple access interference
• 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: H04B 2001/1072 by tuning the receiver frequency
• CPC Class Codes: H04J 11/0023 Interference mitigation or co-ordination direct sequence spread spectrum [DSSS] systems H04B1/7097; frequency hopping H04B1/713; allocation criteria for ingress interference avoidance H04L5/0062; frequency allocation criteria for requirements on out-of-channel emissions H04L5/0066; arrangements for removing intersymbol interference or baseband equalisers H04L25/03006; peak power aspects in multicarrier modulation H04L27/2614; power management H04W52/00; traffic scheduling H04W72/54, H04W72/541
• CPC Class Codes: H04L 27/0006 Assessment of spectral gaps suitable for allocating digitally modulated signals, e.g. for carrier allocation in cognitive radio for spectrum sharing between different networks H04W16/14
• CPC Class Codes: H04L 27/2601 Multicarrier modulation systems
• CPC Class Codes: H04L 43/16 Threshold monitoring
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 48/16 Discovering, processing access restriction or access information
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals
• CPC Class Codes: H04W 88/10 adapted for operation in multiple networks, e.g. multi-mode access points

Abstract

A system that incorporates teachings of the subject disclosure may include, for example, a method for selecting a spectral region in a radio frequency spectrum for initiating a communication session having an uplink and a downlink, correlating a signal strength of portions of the spectral region to generate a correlation factor, detecting radio frequency interference in the spectral region according to the correlation factor, and generating tuning coefficient data to substantially suppress the radio frequency interference in the spectral region during the communication session. Other embodiments are disclosed.

Claims

1. A method, comprising:

scanning, by a communication device, a radio frequency spectrum;

identifying, by the communication device, an available frequency band in the radio frequency spectrum for initiating a communication session having an uplink and a downlink for exchanging data;

selecting, by the communication device, the available frequency band for engaging in communications independent of there being interference in the available frequency band;

determining, by the communication device, a signal strength for each of a plurality of sub-bands in the available frequency band;

determining, by the communication device, a correlation factor by correlating the signal strength for each of the plurality of sub-bands;

detecting, by the communication device, according to the correlation factor a sub-band of the plurality of sub-bands affected by radio interference;

generating, by the communication device, tuning coefficient data to substantially suppress the radio interference in the sub-band while engaged in the communication session;

filtering, by the communication device, a first signal for transmission in the uplink according to the tuning coefficient data to generate a filtered signal; and

transmitting, by the communication device, the filtered signal in the uplink, wherein the filtered signal prevents interference with the radio interference while transmitting in the uplink.

2. The method of claim 1, wherein the plurality of sub-bands have asymmetric bandwidths.

3. The method of claim 1, wherein at least a portion of signals exchanged during the communication session conform to an Orthogonal Frequency-Division Multiple Access (OFDMA) protocol.

4. The method of claim 3, wherein the portion of the signals are associated with the downlink.

5. The method of claim 3, wherein the portion of the signals are associated with the uplink.

6. The method of claim 1, wherein at least a portion of signals exchanged during the communication session conform to one of a Universal Mobile Telecommunications System (UMTS) protocol, or a Groupe Special Mobile (GSM) protocol.

7. The method of claim 1, wherein determining the correlation factor comprises repeating a determination of the signal strength for each of the plurality of sub-bands in the available frequency band.

8. A device, comprising:

a radio frequency transceiver;

a filter apparatus; and

a circuit coupled to the radio frequency transceiver and the filter apparatus, wherein execution of instructions by the circuit cause the circuit to perform operations comprising;

causing the radio frequency transceiver to scan a plurality of spectral regions each comprising sub-bands of varying bandwidths;

selecting an available spectral region from the plurality of spectral regions even when one or more of the sub-bands of the available spectral region are affected by radio frequency interference, wherein the available spectral region is used for initiating a communication session having an uplink and a downlink for exchanging data;

measuring a signal strength in the sub-bands of the available spectral region;

correlating the signal strength of the sub-bands to generate a correlation factor;

detecting radio frequency interference in the available spectral region according to the correlation factor;

generating coefficient data to substantially suppress the radio frequency interference in the available spectral region during the communication session;

causing the filter apparatus to filter a signal for delivery in the uplink according to the coefficient data to generate a filtered signal; and

providing the filtered signal in the uplink.

9. The device of claim 8, wherein each sub-band is a narrowband channel.

10. The device of claim 9, wherein measuring the signal strength in the sub-bands comprises measuring the signal strength in each narrowband channel of the available spectral region.

11. The device of claim 9, wherein detecting the radio frequency interference comprises detecting the radio frequency interference in at least one narrowband channel.

12. The device of claim 8, wherein the circuit further performs operations comprising configuring the filter apparatus according to the coefficient data to substantially suppress the radio frequency interference in the spectral region.

13. The device of claim 12, wherein configuring the filter apparatus comprises tuning the filter apparatus to a filter frequency and a filter bandwidth according to the coefficient data.

14. The device of claim 8, wherein the instructions comprise computer instructions, and wherein the circuit comprises a processor to execute the computer instructions.

15. The device of claim 8, wherein the available spectral region is a wide frequency band, and wherein the device is one of a portable communication device or a base station.

16. The device of claim 8, wherein at least a portion of signals exchanged during the communication session conform to an Orthogonal Frequency-Division Multiple Access (OFDMA) protocol.

17. The device of claim 16, wherein the portion of the signals are associated with one of the downlink or the uplink.

18. A storage device, comprising instructions, which when executed by a circuit, cause the circuit to perform operations comprising:

scanning a spectral region in a radio frequency spectrum for initiating a communication session having an uplink and a downlink;

selecting portions of the spectral region for engaging in the communication session independent of there being interference in the portions of the spectral region;

correlating a signal strength of the portions of the spectral region to generate a correlation factor;

detecting radio frequency interference in the portions of the spectral region according to the correlation factor; and

generating tuning coefficient data to substantially suppress the radio frequency interference in the portions of the spectral region during the communication session;

filtering a first signal for delivery in the uplink according to the tuning coefficient data to generate a filtered uplink signal;

filtering a second signal received in the downlink according to the tuning coefficient data to generate a filtered downlink signal;

supplying the filtered uplink signal in the uplink; and

supplying the filtered downlink signal for further processing.

19. The storage device of claim 18, wherein the portions of the spectral region are narrowband channels, and wherein the circuit further performs operations comprising:

measuring the signal strength in the narrowband channels; and

configuring a filter according to the tuning coefficient data to substantially suppress the radio frequency interference in the spectral region during the communication session.

20. The storage device of claim 18, wherein at least a portion of signals exchanged during the communication session conform to an Orthogonal Frequency-Division Multiple Access (OFDMA) protocol, and wherein the portion of the signals are associated with one of the downlink or the uplink.