Method and apparatus for mitigating signal interference in a feedback system

• US 9,729,301 B2
• Filed: 05/11/2016
• Issued: 08/08/2017
• Est. Priority Date: 03/15/2013
• Status: Active Grant

• Current Assignee: ISCO International Inc.
• Original Assignee: ISCO International Inc.
• Inventors: Cordone, Sean S., Wong, Howard, Abdelmonem, Amr, Galeev, Mikhail
• Primary Examiner(s): LEE, SIU M
• Application Number:
  US15/151,925
• Publication Number:
  US 20160254840A1
• Time in Patent Office: 454 Days
• Field of Search: 375316, 375346, 375349, 375347, 375259, 375285, 375229, 375232, 375233
• 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 1/709 Correlator structure
• CPC Class Codes: H04B 1/71 the interference being narrowband interference
• CPC Class Codes: H04B 1/7103 the interference being multiple access interference
• CPC Class Codes: H04B 15/00 Suppression or limitation of noise or interference by means associated with receiver H04B1/10
• CPC Class Codes: H04B 17/00 Monitoring; Testing of line transmission systems H04B3/46; arrangements for monitoring or testing transmission systems employing electromagnetic waves other than radio waves H04B10/07
• CPC Class Codes: H04B 17/21 for calibration; for correcting measurements
• CPC Class Codes: H04B 17/26 using historical data, averaging values or statistics
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04B 17/327 Received signal code power [RSCP]
• 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 17/373 Predicting channel quality or other radio frequency [RF] parameters
• CPC Class Codes: H04B 2201/709709 Methods of preventing interference
• CPC Class Codes: H04B 2201/709745 Iterative interference mitigation schemes
• CPC Class Codes: H04B 7/2634 for channel frequency control
• CPC Class Codes: H04J 11/0066 of narrowband interference narrowband interference reduction H04B1/1036
• CPC Class Codes: H04L 41/069 using logs of notifications; Post-processing of notifications
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/0026 Division using four or more dimensions
• CPC Class Codes: H04L 5/0032 Distributed allocation, i.e. involving a plurality of allocating devices, each making partial allocation
• CPC Class Codes: H04L 5/006 : Quality of the received signal, e.g. BER, SNR, water filling
• CPC Class Codes: H04L 5/0073 : Allocation arrangements that take into account other cell interferences for intercell interference mitigation or co-ordination in orthogonal multiplex systems H04J11/005
• CPC Class Codes: H04W 16/28 : using beam steering
• CPC Class Codes: H04W 24/02 : Arrangements for optimising operational condition
• CPC Class Codes: H04W 24/08 : Testing, supervising or monitoring using real traffic
• CPC Class Codes: H04W 24/10 : Scheduling measurement reports ; Arrangements for measurement reports
• 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 4/02 : Services making use of location information
• CPC Class Codes: H04W 4/023 : using mutual or relative location information between multiple location based services [LBS] targets or of distance thresholds
• CPC Class Codes: H04W 4/029 : Location-based management or tracking services
• CPC Class Codes: H04W 40/16 : based on interference
• CPC Class Codes: H04W 52/04 : TPC
• CPC Class Codes: H04W 52/14 : Separate analysis of uplink or downlink
• CPC Class Codes: H04W 52/243 : taking into account interferences
• CPC Class Codes: H04W 64/00 : Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: H04W 64/006 : with additional information processing, e.g. for direction or speed determination
• CPC Class Codes: H04W 72/0446 : Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/0453 : Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/52 : based on load
• CPC Class Codes: H04W 72/54 : based on quality criteria
• CPC Class Codes: H04W 72/541 : using the level of interference
• CPC Class Codes: H04W 72/542 : using measured or perceived quality

Abstract

A system that incorporates the subject disclosure may include, for example, a process that includes adjusting a filter in electrical communication between an input terminal and a demodulator. The filter is applied to an information bearing signal, e.g., to mitigate interference, received at the input terminal, resulting in a filtered signal. An error signal is received, indicative of errors detected within information obtained by demodulation of a modulated carrier of the filtered signal. A modified filter state is determined in response to the error signal and the filter is adjusted according to the modified filter state, e.g., to improve mitigation of the interference. Other embodiments are disclosed.

Claims

1. A method, comprising:

measuring, by a system comprising a processor, a plurality of power levels associated with a first plurality of spectral segments over a first radio spectrum of a first wireless communication system;

calculating, by the system, a first plurality of power levels for the first plurality of spectral segments;

averaging, by the system, the first plurality of power levels to determine a baseline average power level for the first radio spectrum;

determining, by the system, interference within a spectral segment of the first plurality of spectral segments according to a threshold determined from the baseline average power level;

accessing historical observations of past interference from an interference database; and

adjusting, by the system, a system parameter of an adaptive filter according to the historical observations as a first mitigation of the interference, resulting in a pre-adjusted system parameter.

2. The method of claim 1, further comprising:

receiving, by the system, signal information associated with errors corrected responsive to filtering a signal according to the pre-adjusted system parameter; and

adjusting, by the system, the pre-adjusted system parameter of the adaptive filter for a second mitigation of the interference according to the signal information.

3. The method of claim 1, wherein the adaptive filter comprises a transfer function to reject a portion of the interference.

4. The method of claim 3, wherein the adjusting of the system parameter of the adaptive filter further comprises providing tuning coefficient data based on the transfer function of the adaptive filter.

5. The method of claim 3, wherein the adjusting of the system parameter of the adaptive filter further comprises providing a filter control signal to the adaptive filter based on the transfer function.

6. The method of claim 3, wherein the transfer function comprises adjusting of one of a filter width, a filter depth, a filter shape, or a combination thereof.

7. The method of claim 1, wherein the adaptive filter comprises a plurality of filters.

8. The method of claim 7, wherein the plurality of filters are implemented using infinite impulse response filters, finite impulse response filters, or combination thereof.

9. The method of claim 1, wherein the adaptive filter is implemented in a field programmable gate array.

10. A device, comprising:

a processing system including a processor; and

a memory that stores executable instructions that, when executed by the processing system, facilitate performance of operations, comprising;

measuring a plurality of power levels for a plurality of spectral segments over a radio spectrum of a wireless communication system;

determining a baseline average power level for the radio spectrum according to the plurality of power levels for the spectral segments of the radio spectrum;

determining a threshold from the baseline average power level for detecting signal interference in the spectral segments of the radio spectrum of the wireless communication system;

accessing historical observations of past interference from an interference database; and

adjusting a system parameter of an adaptive filter for filtering an information bearing signal that is received at an input terminal according to the historical observations, resulting in a filtered signal.

11. The device of claim 10, wherein the operations further comprise:

receiving a first error signal indicative of errors corrected within information obtained from the filtered signal; and

adjusting the system parameter of the adaptive filter based on the first error signal.

12. The device of claim 10, wherein the adaptive filter comprises a transfer function to reject a portion of the signal interference.

13. The device of claim 12, wherein the adjusting of the system parameter of the adaptive filter further comprises providing tuning coefficient data based on the transfer function of the adaptive filter.

14. The device of claim 12, wherein the adjusting of system parameter of the adaptive filter further comprises providing a filter control signal to the adaptive filter based on the transfer function.

15. The device of claim 10, wherein the adaptive filter comprises a plurality of filters that are implemented using infinite impulse response filters, finite impulse response filters, or combination thereof.

16. The device of claim 10, wherein the adaptive filter comprises a plurality of filters.

17. The device of claim 10, wherein the adaptive filter is implemented in a field programmable gate array.

18. A non-transitory machine-readable storage device, comprising executable instructions that, when executed by a processing system including a processor, facilitate performance of operations comprising:

measuring a plurality of power levels for a plurality of spectral segments over a radio spectrum of a wireless communication system;

determining a baseline average power level for the radio spectrum according to the plurality of power levels for the spectral segments of the radio spectrum;

determining a threshold from the baseline average power level for detecting signal interference in the spectral segments of the radio spectrum of the wireless communication system;

accessing historical observations of past interference from an interference database; and

adjusting an adaptive filter according to a filter state according to the historical observations, for filtering an information bearing signal that is received at an input terminal, resulting in a filtered signal wherein the adjusting of the adaptive filter is based on the signal interference that is detected.

19. The non-transitory machine-readable storage device of claim 18, wherein the operations further comprise:

receiving a first error signal indicative of errors corrected within information obtained from the filtered signal; and

adjusting the adaptive filter based on the first error signal.

20. The non-transitory machine-readable storage device of claim 18, wherein the adaptive filter comprises a transfer function to reject a portion of the signal interference, wherein the adjusting of the adaptive filter further comprises providing tuning coefficient data based on the transfer function, and wherein the adjusting of the adaptive filter further comprises providing a filter control signal to the adaptive filter based on the transfer function.