Method and apparatus for an adaptive filter architecture

• US 8,724,756 B2
• Filed: 09/14/2012
• Issued: 05/13/2014
• 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
• Application Number:
  US13/617,720
• Publication Number:
  US 20130010629A1
• Time in Patent Office: 606 Days
• Field of Search: 375/350, 375/346, 375/148, 455/296, 455/278, 455/306, 370/335, 370/252, 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 identifying a spectral region in a radio frequency spectrum for initiating a communication session having a transmission link and a reception link, determining a correlation factor from signals measured in the spectral region, detecting according to the correlation factor a foreign communication signal in the spectral region, generating coefficient data to prevent interference with the foreign communication signal while transmitting in the transmission link, filtering a first signal for transmission in the transmission link according to the coefficient data to generate a filtered signal, and causing a transmission of the filtered signal which prevents interference with the foreign communication signal while transmitting in the transmission link. Other embodiments are disclosed.

Claims

1. A method, comprising:

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

identifying, by the communication device, an available frequency band in the radio frequency spectrum for initiating a communication session having a transmission link and a reception link 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 in portions of the available frequency band;

determining, by the communication device, a correlation factor by correlating the signal strength in the portions of the available frequency band;

detecting, by the communication device, according to the correlation factor a foreign communication signal in the available frequency band;

generating, by the communication device, tuning coefficient data to prevent interference with the foreign communication signal while transmitting in the transmission link;

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

transmitting, by the communication device, the filtered signal in the transmission link, wherein the filtered signal prevents interference with the foreign communication signal while transmitting in the transmission link.

2. The method of claim 1, wherein the foreign communication signal is generated by heterogeneous networks in the communication network designed to coexist in the available frequency band.

3. The method of claim 2, wherein the heterogeneous networks operate according to disparate communication protocols.

4. 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, and wherein the portion of the signals are associated with one of the reception link or the transmission link.

5. The method of claim 1, wherein determining the correlation factor comprises repeating a determination of the signal strength in the portions of the available frequency band.

6. The method of claim 1, comprising:

receiving a second signal in the reception link; and

filtering the second signal according to the tuning coefficient data to substantially suppress the foreign communication signal in the reception link.

7. The method of claim 1, wherein the communication device is one of a mobile phone or a cellular base station.

8. A device, comprising:

a radio frequency transceiver; and

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

causing the radio frequency transceiver to scan a spectral region in a radio frequency spectrum for initiating a communication session having a transmission link and a reception link;

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

determining a signal strength in the portions of the spectral region;

determining a correlation factor by correlating the signal strength in the portions of the spectral region;

detecting according to the correlation factor a foreign communication signal in the spectral region;

generating coefficient data to prevent interference with the foreign communication signal while transmitting in the transmission link;

filtering a first signal for transmission in the transmission link according to the coefficient data to generate a filtered signal; and

causing the radio frequency transceiver to transmit the filtered signal in the transmission link, wherein the filtered signal prevents interference with the foreign communication signal while transmitting in the transmission link.

9. The device of claim 8, wherein the foreign communication signal is generated by heterogeneous networks designed to coexist in the spectral region.

10. The device of claim 9, wherein the heterogeneous networks operate according to disparate communication protocols.

11. The device of claim 8, wherein the spectral region comprises narrowband channels.

12. The device of claim 8, comprising a filter apparatus, wherein the circuit further performs operations comprising configuring the filter apparatus according to the coefficient data to generate the filtered signal.

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 circuit further performs operations comprising causing the radio frequency transceiver to receive a second signal in the reception link.

16. The device of claim 15, wherein the circuit further performs operations comprising filtering the second signal according to the coefficient data to substantially suppress the foreign communication signal in the reception link.

17. 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, and wherein the portion of the signals are associated with one of the reception link or the transmission link.

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

identifying a spectral region in a radio frequency spectrum for initiating a communication session having a transmission link and a reception link;

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

determining a correlation factor from signals measured in the spectral region;

detecting according to the correlation factor a foreign communication signal in the spectral region;

generating coefficient data to prevent interference with the foreign communication signal while transmitting in the transmission link;

filtering a first signal for transmission in the transmission link according to the coefficient data to generate a filtered signal; and

causing a transmission of the filtered signal in the transmission link, wherein the filtered signal prevents interference with the foreign communication signal while transmitting in the transmission link.

19. The storage device of claim 18, wherein the circuit further performs operations comprising:

receiving a second signal in the reception link; and

filtering the second signal according to the coefficient data to substantially suppress the foreign communication signal in the reception link.

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 reception link or the transmission link.