Methods for estimation and interference suppression for signal processing

• US 8,848,765 B2
• Filed: 06/03/2013
• Issued: 09/30/2014
• Est. Priority Date: 09/23/2002
• Status: Active Grant

• Current Assignee: III Holdings 1, LLC
• Original Assignee: III Holdings 1, LLC
• Inventors: Lamba, Gagandeep Singh, Guess, Tommy, McCloud, Michael, Narayan, Anand P.
• Primary Examiner(s): Tran, Khai
• Application Number:
  US13/908,286
• Publication Number:
  US 20140003471A1
• Time in Patent Office: 484 Days
• Field of Search: 375/148, 375/130, 375/144, 375/147, 375/316, 375/347, 375/348, 375/349, 370/320, 370/335, 370/342, 455/334
• US Class Current: 375/148
• CPC Class Codes: H04B 1/7097 Interference-related aspects
• CPC Class Codes: H04B 1/7107 Subtractive interference cancellation
• CPC Class Codes: H04B 1/71072 Successive interference cancellation
• CPC Class Codes: H04B 1/71075 Parallel interference cancellation
• CPC Class Codes: H04B 1/7115 Constructive combining of multi-path signals, i.e. RAKE receivers
• CPC Class Codes: H04B 1/7117 Selection, re-selection, allocation or re-allocation of paths to fingers, e.g. timing offset control of allocated fingers
• CPC Class Codes: H04B 15/00 Suppression or limitation of noise or interference by means associated with receiver H04B1/10
• CPC Class Codes: H04B 2001/71077 Partial interference cancellation
• CPC Class Codes: H04B 2201/709718 Determine interference
• CPC Class Codes: H04J 13/00 Code division multiplex systems for frequency hopping H04B1/713
• CPC Class Codes: H04J 13/0048 Walsh
• CPC Class Codes: H04L 43/08 Monitoring or testing based on specific metrics, e.g. QoS, energy consumption or environmental parameters
• CPC Class Codes: H04W 24/08 Testing, supervising or monitoring using real traffic

Abstract

A receiver in a CDMA system comprises a front end processor that generates a combined signal per source. A symbol estimator processes the combined signal to produce symbol estimates. An S-Matrix Generation module refines these symbol estimates based on the sub channel symbol estimates. An interference canceller is configured for cancelling interference from at least one of the plurality of received signals for producing at least one interference-cancelled signal.

Claims

1. A receiver, comprising:

a front end comprising a plurality of fingers and a finger combiner configured to combine a plurality of received signals from the plurality of fingers to produce a combined signal;

a symbol estimator configured to process the combined signal to produce one or more symbol estimates;

a symbol quality estimator configured to operate on the one or more symbol estimates to generate one or more symbol quality estimates based on the one or more symbol estimates;

a processor configured to combine the one or more symbol estimates with the one or more symbol quality estimates to obtain a cancelation vector for at least one of a plurality of user subchannels;

an interference canceller configured to cancel interference from at least one of the plurality of received signals based on the cancelation vector to produce at least one interference-cancelled signal; and

a control switch configured to produce a routing decision based on estimated signal quality for each interference-cancelled signal and estimated signal quality from at least one of the plurality of received signals.

2. The receiver of claim 1, wherein the control switch is further configured to make the routing decision once for every symbol estimate.

3. The receiver of claim 1, wherein the control switch is further configured to make the routing decision over a predetermined number of symbol estimates.

4. The receiver of claim 1, wherein the control switch is further configured to route signals from a plurality of antennae to the plurality of fingers based on the routing decision.

5. The receiver of claim 1, wherein the control switch is further configured to determine estimated signal quality for each interference-cancelled signal based on signal-to-noise ratios.

6. The receiver of claim 1, wherein the control switch is further configured to determine estimated signal quality for each interference-cancelled signal based on signal-to-interference plus noise ratios.

7. The receiver of claim 1, wherein the plurality of fingers comprises a single finger configured to process multipaths in a Time Division Multiplex mode.

8. A method, comprising:

combining a plurality of received signals from a plurality of fingers to produce a combined signal;

processing the combined signal to produce one or more symbol estimates;

operating on the one or more symbol estimates to generate one or more symbol quality estimates based on the one or more symbol estimates;

combining the one or more symbol estimates with the one or more symbol quality estimates to obtain a cancelation vector for at least one of a plurality of user subchannels;

cancelling interference from at least one of the plurality of received signals based on the cancelation vector to produce at least one interference-cancelled signal; and

routing signals to the plurality of fingers based on estimated signal quality for each interference-cancelled signal and estimated signal quality from at least one of the plurality of received signals.

9. The method of claim 8, further comprising selecting routes to the plurality of fingers on a per symbol basis.

10. The method of claim 8, further comprising selecting routes to the plurality of fingers on a predetermined number of symbols basis.

11. The method of claim 8, wherein said routing comprises routing signals from a plurality of antennae to the plurality of fingers.

12. The method of claim 8, further comprising determining estimated signal quality for each interference-cancelled signal based on signal-to-noise ratios.

13. The method of claim 8, further comprising determining estimated signal quality for each interference-cancelled signal based on signal-to-interference plus noise ratios.

14. An apparatus, comprising:

a plurality of antennae configured to receive a plurality of multipath signals; and

a receiver configured to;

combine the plurality of multipath signals into a combined signal;

process the combined signal to produce one or more symbol estimates;

operate on the one or more symbol estimates to generate one or more symbol quality estimates based on the one or more symbol estimates;

combine the one or more symbol estimates with the one or more symbol quality estimates to obtain a cancelation vector for at least one of a plurality of user subchannels;

cancel interference from at least one of the plurality of received signals based on the cancelation vector to produce at least one interference-cancelled signal; and

route the plurality of multipath signals based on estimated signal quality for each interference-cancelled signal and estimated signal quality from at least one of the plurality of received signals.

15. The apparatus of claim 14, wherein the receiver is further configured to select routes on a per symbol basis.

16. The apparatus of claim 14, wherein the receiver is further configured to select routes on a predetermined number of symbols basis.

17. The apparatus of claim 14, wherein the receiver is further configured to route the plurality of multipath signals from the plurality of antennae to a plurality of fingers.

18. The apparatus of claim 14, wherein the receiver is further configured to route the plurality of multipath signals to a single finger configured to process the plurality of multipath signals in a Time Division Multiplex mode.

19. The apparatus of claim 14, wherein the receiver is configured to determine estimated signal quality based on signal-to-noise ratios.

20. The apparatus of claim 14, wherein the receiver is configured to determine estimated signal quality based on signal-to-interference plus noise ratios.