Adaptive array antenna and interference canceler in a mobile communications system

• US 6,771,986 B1
• Filed: 07/15/1998
• Issued: 08/03/2004
• Est. Priority Date: 07/15/1997
• Status: Expired due to Term

• Current Assignee: Samsung Electronics Co. Ltd., Schlumberger Technology Corporation (Schlumberger NV)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Oh, Chang-Hun
• Primary Examiner(s): Gesesse, Tilahun
• Application Number:
  US09/116,018
• Time in Patent Office: 2,211 Days
• Field of Search: 455/296, 455/561, 455/562, 455/63, 455/67.3, 455/67.6, 455/303, 455/307, 342/379, 342/384, 342/381, 375/346, 375/137, 375/149
• US Class Current: 455/562.1
• CPC Class Codes: H04B 1/7097 Interference-related aspects
• CPC Class Codes: H04B 1/7105 Joint detection techniques, e.g. linear detectors
• CPC Class Codes: H04B 7/086 using weights depending on external parameters, e.g. direction of arrival [DOA], predetermined weights or beamforming

Abstract

A receiver in a mobile communications system is provided. The receiver includes an adaptive array antenna having a plurality of antenna elements for forming a beam in the direction of a desired signal. Each of the plurality of elements has an adaptive linear filter associated therewith. A real time adaptive receive processor controls beam patterns and directions of the plurality of antenna elements at a reception angle of the desired user. An interference canceller operatively connected to said adaptive array antenna detects a multi-user interference signal from the desired signal and cancels the multi-user signal.

Claims

1. A receiving method in a Code Division Multiple Access (CDMA mobile communications system, comprising the steps of:

controlling beam patterns and directions of an adaptive array antenna to coincide with a reception direction of a desired signal;

forming a beam in the reception direction of the desired signal;

eliminating an interference signal received at a different angle than the reception angle of the desired signal; and

eliminating multiple access interference signals included in signals received at the reception angle of the desired signal.

2. The method of claim 1, wherein said controlling step is performed by a real time adaptive receive processor associated with the adaptive array antenna, said adaptive receive processor being serially connected with a interference canceller, said interference canceller for eliminating multiple access interference signals included in signals received at the reception angle of the desired signal.

3. The method of claim 2, wherein the interference canceller is comprised of a plurality of interference detectors, each of the plurality of detectors including a first mixer, an integrator, a correlator, and a second mixer, said first mixer for spreading a received signal with a Pseudo-Noise (PN) code corresponding to another user, said integrator for accumulating the output signal of the first mixer, said correlator for detecting a signal correlation value of the another user, and said second mixer for spreading the correlatively detected signal with the PN code corresponding to the another user.

4. The method of claim 1, wherein the adaptive array antenna includes a plurality of antenna elements, each element of the plurality of elements having an adaptive linear filter associated therewith, and said controlling step controls beam patterns and directions of the plurality of antenna elements.

5. The method of claim 4, wherein said forming step is performed by the plurality of elements.

6. The method of claim 1, wherein the formed beam is directed horizontally at 360 degrees.

7. The method of claim 1, wherein said eliminating step further comprises the step of null-steering to eliminate the interference signal.

8. A receiving method in a Code Division Multiple Access (CDMA) mobile communications system, comprising the steps of:

eliminating an interference signal received at a different direction than a reception direction of a desired signal by controlling beam patterns and directions of an adaptive array antenna to coincide with the reception direction of the desired signal;

forming a beam in the reception direction of the desired signal;

detecting multiple access interference signals included in signals received at the reception angle of the desired signal; and

eliminating, the detected multiple access interference signals in signals received at the reception angle of the desired signal.

9. The method of claim 8, wherein said detecting step is performed by a plurality of interference detectors in an interference canceller, each of the plurality of detectors including an input mixer, an integrator, and a filter, said interference canceller being serially connected with an adaptive receive processor.

10. The method of claim 9, wherein each of the plurality of interference detectors further comprises a correlator, and an output mixer, said input mixer for spreading a received signal with a Pseudo-Noise (PN) code corresponding to another user, said integrator for accumulating the output signal of the input mixer, said correlator for detecting a signal correlation value of the another user, and said output mixer for spreading the correlatively detected signal with the PN code corresponding to the another user.

11. A receiver in a Code Division Multiple Access (CDMA) mobile communications system, comprising:

an adaptive array antenna having a plurality of antenna elements for forming a beam in the direction of a desired signal, each of the plurality of elements having an adaptive linear filter associated therewith;

a real time adaptive receiver processor for controlling beam patterns and directions of the plurality of antenna elements at a reception angle of the desired signal; and

an interference canceller operatively connected to said adaptive array antenna, for detecting multiple access interference signals in signals received at the reception angle of the desired signal and for eliminating the detected multiple access interference signals.

12. The receiver of claim 11, wherein said interference canceller comprises a plurality of interference, signal detectors, each of the plurality of detectors including an input mixer, an integrator, and a filter, said interference canceller being serially connected with an adaptive receive processor.

13. The receiver of claim 12, wherein each of the plurality of interference signal detectors further comprises:

a correlator for detecting a signal correlation value of another user; and

an output mixer for spreading the correlatively detected signal with the PN code corresponding to said another user;

wherein said input mixer is for spreading a received signal with a Pseudo-Noise (PN) code corresponding to said another user, and said integrator is for accumulating the output signal of the input mixer.

14. The receiver of claim 11, wherein said antenna and said canceller are serially connected.

15. A receiver in a Code Division Multiple Access (CDMA) mobile communications system, comprising:

a plurality of antenna elements for forming a beam in the direction of a desired signal, each of the plurality of elements having an adaptive linear filter; and

a real time adaptive receiver processor for controlling beam patterns and directions of the plurality of antenna elements at a reception angle of the desired signal, wherein said plurality of elements and said processor eliminate an interference signal received at a different angle than that of the desired signal, wherein said plurality of elements and said processor further eliminate multiple access interference signals in signals received at the reception angle of the desired signal.

16. The device of claim 15, further comprising:

an interference canceller for cancelling multiple access interference signals from the desired signal.

17. The device of claim 16, the interference canceller comprising:

a plurality of interference detectors, each of the plurality of detectors comprising;

a first mixer for spreading the received signal with a Pseudo-Noise (PN) code corresponding to another user;

an integrator for accumulating the output signal of the first mixer;

a correlator for detecting a signal correlation value of the another user; and

a second mixer for spreading the correlatively detected signal with the PN code corresponding to the another user.