Method and apparatus for an adaptive filter architecture

• US 9,647,720 B2
• Filed: 05/30/2014
• Issued: 05/09/2017
• Est. Priority Date: 11/11/2008
• Status: Active Grant

• Current Assignee: ISCO International Inc.
• Original Assignee: ISCO International Inc.
• Inventors: Abdelmonem, Amr, Cordone, Sean S.
• Primary Examiner(s): TAYONG, HELENE E
• Application Number:
  US14/291,032
• Publication Number:
  US 20140269248A1
• Time in Patent Office: 1,075 Days
• Field of Search: 375350, 375346, 375203, 375142, 375148, 455307
• 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:

identifying, by a system comprising a processor, an available portion of a radio frequency spectrum for initiating a communication session having an uplink and a downlink for exchanging data;

selecting, by the system, the available portion of the radio frequency spectrum for engaging in communications independent of there being interference in the available portion of the radio frequency spectrum;

determining, by the system, a signal strength for each of a plurality of bands in the available portion of the radio frequency spectrum;

determining, by the system, a correlation factor for select bands that have a signal strength greater than other bands in the plurality of bands;

detecting, by the system, radio frequency interference in at least one band of the plurality of bands according to the correlation factor, wherein the radio frequency interference includes a plurality of interference signals;

generating, by the system, tuning coefficient data to suppress at least a portion of the radio frequency interference including the plurality of interference signals in the at least one band while engaged in the communication session;

receiving, by the system, a first signal in the available portion of the radio frequency spectrum; and

filtering, by the system, the first signal according to the tuning coefficient data to filter the radio frequency interference using a filter, wherein the filter is a combination of notch filters, and wherein each notch frequency of the notch filters corresponds to a frequency of one of the plurality of interference signals.

2. The method of claim 1, wherein the plurality of 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 1, wherein a band in the plurality of bands is associated with a downlink of the available portion of the radio frequency spectrum.

5. The method of claim 1, wherein a band in the plurality of bands is associated with the uplink of the available portion of the radio frequency spectrum.

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 the determining of the correlation factor comprises cross-correlating a signal in each band with itself.

8. A device, comprising:

a radio frequency transceiver;

a filter; and

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

causing the radio frequency transceiver to monitor a plurality of spectral regions;

selecting an available spectral region from the plurality of spectral regions even when the available spectral region is affected by interference, wherein the available spectral region is used for initiating a communication session having an uplink and a downlink for exchanging data;

generating a correlation factor for the available spectral region;

detecting interference in the available spectral region according to the correlation factor, wherein the interference includes a plurality of interference signals;

generating coefficient data to suppress at least a portion of the interference including the plurality of interference signals in the available spectral region during the communication session; and

causing the filter to filter a signal received in the available spectral region according to the coefficient data to filter at least a portion of the interference including the plurality of interference signals, wherein the filter is a combination of notch filters, and wherein each notch frequency of the notch filters corresponds to a frequency of one of the plurality of interference signals.

9. The device of claim 8, wherein the correlation factor is generated for each channel in the available spectral region.

10. The device of claim 9, wherein the operations further comprise measuring a power level in each channel of the available spectral region.

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

12. The device of claim 8, wherein the causing of the filter to filter the signal comprises configuring the filter according to the coefficient data to filter at least the portion of the interference in the available spectral region.

13. The device of claim 12, wherein the configuring the filter comprises tuning the filter 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 the downlink or the uplink of the communication session.

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

monitoring a spectral region in a radio frequency spectrum for initiating a communication session;

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 in the portions of the spectral region to generate a correlation factor;

detecting interference in the portions of the spectral region according to the correlation factor, wherein the interference includes a plurality of interference signals;

generating tuning coefficient data to suppress at least a portion of the interference including the plurality of interference signals in the portions of the spectral region during the communication session;

filtering a signal received in a downlink of the portions of the spectral region using a filter according to the tuning coefficient data to generate a filtered downlink signal, wherein the filter is a combination of notch filters, and wherein each notch frequency of the notch filters corresponds to a frequency of one of the plurality of interference signals; and

supplying the filtered downlink signal for further processing.

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

measuring signal strength in the channels; and

configuring the filter according to the tuning coefficient data to suppress at least the portion of the interference in the portions of 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 an uplink of the communication session.