METHODS AND SYSTEMS FOR PROCESSING RECEIVED SIGNALS FOR A WIRELESS NETWORK RECEIVER

• US 20150381221A1
• Filed: 02/13/2014
• Published: 12/31/2015
• Est. Priority Date: 02/14/2013
• Status: Active Grant

• Current Assignee: Ubiqam Ltd.
• Original Assignee: Ubiqam Ltd.
• Inventors: CYZS, Baruch, MEIR, Amir, MANOR, Daniel, AMIDAN, Oren
• Granted Patent: US 9,496,904 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04B 1/1027 assessing signal quality or detecting noise/interference for the received signal
• CPC Class Codes: H04B 1/7097 Interference-related aspects
• CPC Class Codes: H04B 7/086 using weights depending on external parameters, e.g. direction of arrival [DOA], predetermined weights or beamforming
• CPC Class Codes: H04J 11/0066 of narrowband interference narrowband interference reduction H04B1/1036
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA

Abstract

There is provided systems and methods for mitigating foreign interference by complementing a receiver of a wireless network, comprising: using antennas for reception of desired signals and interference signals; determining the presence of an interference signal originating from at least one foreign transmitting source in the received signals, and for determining a termination of the interference signal; determining the presence of a desired signal originating from the wireless communication network in the received signals; calculating a suitable combination of the received signals, wherein the effect induced by the interference signal is reduced and the impact of an interference cancellation on the desired signals is reduced; and providing the suitable combination to a receiver of a wireless communication network; wherein the method is performed complementary to the receiver of the wireless network and the antennas.

Claims

1. An add-on receiver module for mitigating foreign interference complementing a receiver of a wireless network, the receiver module comprising:

a first interface for electrically coupling to a plurality of antennas for reception of desired signals and interference signals;

wherein the plurality of antennas are arranged in an antenna diversity scheme;

a hardware processor; and

a non-transitory memory having stored thereon program modules for instruction execution by the hardware processor, comprising;

an interference determination module for determining the presence of an interference signal originating from at least one foreign external transmitting source in the received signals, and for determining a termination of the interference signal;

a desired signal detection module for determining the presence of a desired signal originating from the wireless communication network in the received signals;

an interference cancellation module for calculating a suitable combination of the received signals, wherein the effect induced by the interference signal is reduced and the impact of an interference cancellation on the desired signals is reduced; and

a second interface for electrically coupling to a receiver unit of the wireless communication network, wherein the suitable combination is provided to the receiver unit by the second interface;

wherein the receiver module operates complementary to the receiver unit of the wireless network and the plurality of antennas;

wherein the receiver module is coupled within a signal receive path between the plurality of antennas of the receiver unit and the antenna ports of the receiver unit.

3. The receiver module of claim 1, wherein the interference determination module determines the presence of the interference signal based on the received signals without additional information from the wireless network, the desired signal detection module determines the presence of the desired signal based on the received signals without additional information from the wireless network, and the interference cancellation module calculates the suitable combination without additional information from the wireless network.

4. The receiver module of claim 3, wherein without additional information comprises one or more of:

controlling transmission of signals within the wireless communication network, requesting transmission of special signals, muting the wireless communication network, and polling elements within the wireless communication network, and exploiting instantaneous signature within the desired signals, and exploiting one or more of;

pilot signals, preamble signals, sounding signals within the desired signals.

7. The receiver module of claim 1, wherein the receiver module operates externally to the receiver unit of the wireless communication network and the plurality of antennas.

8. The receiver module of claim 1, further comprising a synthetic noise module for injecting synthetic correlated noise signals into each received desired signals antenna input, the number of injected correlated noise signals being equal to the number of antennas, the synthetic noise generated to prevent suppression of received desired signals when a number of transmitting client transceivers is lower than the number of antennas, the suitable combination based on the injected synthetic correlated noise signals.

9. The receiver module of claim 1, wherein concurrent interference signals in the same frequency sub-bands are received with concurrent desired signals in the same frequency sub-bands, the received power of the interference signals being significantly higher than the received power of the desired signal, the suitable combination calculated such that cancellation weights calculated based on existence of interference and desired signal reject the output interference signal, and leave the desired signal provided to the receiver of a base station substantially unaffected.

10. The receiver module of claim 1, wherein the interference cancellation module is further programmed calculate the suitable combination based on calculating a plurality of cancellation weights, the cancellation weights correspond frequency sub-bands that do not carry dominant interference signals are set to zero, so that a diversity scheme of the received signals is substantially preserved for performance of the diversity scheme in the receiver of a base station, and the expected change in the wireless channel of the received desired signal as measured by the base station in frequency sub-bands where there are no dominant interference signals is negligible.

15. The receiver module of claim 1, wherein the interference determination module and/or the desired signal detection module are further programmed to determine when the power level of the interference signals is near or less than the power level of desired signals, the suitable combination based on the detected power level.

16. The receiver module of claim 1, wherein the suitable combination is based on avoiding cancellation of a desired signal rather than interference signals.

17. The receiver module of claim 1, wherein the interference determination module and/or the desired signal detection module further comprise a time periods detection module for detecting time periods where desired signals are not received, and identifying the interference signals during the time periods.

19. The receiver module of claim 1, wherein the interference determination module and/or the desired signal detection module are further programmed to determine based on detecting received desired signals based on certain characteristics of the received desired signals.

20. The receiver module of claim 1, further comprising one or more switch modules for directing the received signals to interference cancellation or to diversity reception, based on the interference determination module determination, the suitable combination comprising applying interference cancellation or diversity reception.

21. The receiver module of claim 1, wherein the receiver module is arranged as a self-contained structure for coupling to the receiver of the wireless network and the plurality of antennas.

22. The receiver module of claim 1, wherein the number of antenna inputs into the first interface is higher than the number of signal outputs to the receiver through the second interface, wherein the number of interference signals is less than the number of antennas minus one, wherein there are sufficient degrees of freedom to perform the interference cancellation and to preserve the inherent diversity gain.

23. The receiver module of claim 22, wherein the receiver module provides to the receiver inputs signals with reduced cross correlation among each antenna input couple, so that diversity gain is achieved by providing to each receiver input different composite antenna array patterns through certain settings of beam former weights, wherein each receiver is connected to certain composite antenna array patterns with common nulls toward the interference signal direction and/or polarization, with a beam steered toward different direction and/or polarization of a base station cell geometry.

25. The receiver module of claim 1, wherein the desired signal detection module for determining the presence of a desired signal originating from the wireless communication network in the received signals exploits long term known statistic parameters of the desired signals.

79. The receiver module of claim 1, further comprising:

one or more switch modules for directing the received signals to interference cancellation or to diversity reception, based on the interference determination module determination.

85. The receiver module of claim 79, wherein the same antenna port is used for transmitting and receiving RF signals, wherein the switch modules are in electrical communication between the antennas and an interference cancellation unit, and between the interference cancellation unit and receiving circuitry, the switch modules programmed to direct signals on an uplink path through the interference cancellation unit, and to direct signals on a downlink path to bypass the interference cancellation unit.

86. The receiver module of claim 79, wherein at least one of the switch modules is a duplexing filter for the system operating with Frequency-division duplexing, or a switch for the system operating with time-division duplexing.

87. The receiver module of claim 1, further comprising a remote radio head (RRH) located remotely from the hardware processor, the RRH communicating with the hardware processor using wired links transmitting digital signals, and a module stored on the memory containing program instruction for receiving digital baseband signals from the RRH, performing interference cancellation on the received digital baseband signals to generate a clean digital baseband signals, and transmitting the clean digital baseband signals over the wired link to the hardware processor.

88. The receiver module of claim 79, wherein the hardware processor, the non-transitory memory, and the switching module are integrated into an interference cancellation unit that is a stand-alone device.

89. The receiver module of claim 79, wherein the hardware processor, the non-transitory memory, and the switching module are disposed within an existing housing.

90. The receiver module of claim 79, further comprising a synchronization mechanism for coordination between receiving circuitry and the switching module for communication of time periods when there is no reception of desired signals, and wherein the switching module detects the interference signals based on the time periods.

91. The receiver module of claim 79, further comprising a module for calculating interference cancellation weights for cancelling the interference signals.

2. (canceled)

5-6. -6. (canceled)

11-14. -14. (canceled)

18. (canceled)

24. (canceled)

26. A method for mitigating foreign interference by complementing a receiver of a wireless network, comprising:

using a plurality of antennas for reception of desired signals and interference signals;

wherein the plurality of antennas are arranged in an antenna diversity scheme;

determining the presence of an interference signal originating from at least one foreign external transmitting source in the received signals, and determining a termination of the interference signal;

determining the presence of a desired signal originating from the wireless communication network in the received signals;

calculating a suitable combination of the received signals, wherein the effect induced by the interference signal is reduced and the impact of an interference cancellation on the desired signals is reduced; and

providing the suitable combination to a receiver of a wireless communication network;

wherein the method is complementing a receiver of the wireless network and the plurality of antennas.

28. The method of claim 26, wherein the presence of the interference signal is determined based on the received signals without additional information from the wireless network, the presence of the desired signal is determined based on the received signals without additional information from the wireless network, and the suitable combination is calculated without additional information from the wireless network.

29. The method of claim 28, wherein without additional information comprises one or more of:

controlling transmission of signals within the wireless communication network, requesting transmission of special signals, muting the wireless communication network, and polling elements within the wireless communication network, and exploiting instantaneous signature within the desired signals, and exploiting one or more of;

pilot signals, preamble signals, sounding signals within the desired signals.

32. The method of claim 26, wherein the method is performed externally to the receiver of the wireless communication network and the plurality of antennas.

33. The method of claim 26, further comprising injecting synthetic correlated noise signals into each received desired signals antenna input, the number of injected correlated noise signals being equal to the number of antennas, the synthetic noise generated to prevent suppression of received desired signals when a number of transmitting client transceivers is lower than the number of antennas, the suitable combination based on the injected synthetic correlated noise signals.

34. The method of claim 26, wherein concurrent interference signals in the same frequency sub-bands are received with concurrent desired signals in the same frequency sub-bands, the received power of the interference signals being significantly higher than the received power of the desired signal, the suitable combination calculated such that the cancellation weights calculated based on existence of interference and desired signal reject the output interference signal, and leave the desired signal provided to the receiver of a base station substantially unaffected.

35. The method of claim 26, wherein calculating comprises calculating the suitable combination based on calculating a plurality of cancellation weights, the cancellation weights correspond to frequency sub-bands that do not carry dominant interference signals are set to zero, so that a diversity scheme of the received signals is substantially preserved for performance of the diversity scheme in the receiver of a base station, and the expected change in the wireless channel of the received desired signal as measured by the base station in frequency sub-bands where there are no dominant interference signals is negligible.

40. The method of claim 26, wherein determining comprises determining when the power level of the interference signals is near or less than the power level of desired signals, the suitable combination based on the detected power level.

41. The method of claim 26, wherein the suitable combination is based on avoiding cancellation of a desired signal rather than interference signals.

42. The method of claim 26, wherein determining comprises determining by detecting time periods where desired signals are not received, and identifying the interference signals during the time periods.

44. The method of claim 26, wherein determining comprises determining based on detecting received desired signals based on certain characteristics of the received desired signals.

45. The method of claim 26, further comprising switching the received signals to interference cancellation or to diversity reception, based on the interference signal determination, the suitable combination comprising applying interference cancellation or diversity reception.

46. The method of claim 26, wherein the number of received antenna inputs is higher than the number of signal outputs to the receiver, wherein the number of interference signals is less than the number of antennas minus one, wherein there are sufficient degrees of freedom to perform the interference cancellation and to preserve the inherent diversity gain.

47. The method of claim 46, wherein providing comprises providing to the receiver inputs signals with reduced cross correlation among each antenna input couple, so that diversity gain is achieved by providing to each receiver input different composite antenna array patterns through certain settings of beam former weights, wherein each receiver is connected to certain composite antenna array patterns with common nulls toward the interference signal direction and/or polarization, with a beam steered toward different direction and/or polarization of a base station cell geometry.

49. The method of claim 26, wherein determining the presence of a desired signal originating from the wireless communication network in the received signals is performed based on exploiting long term known statistic parameters of the desired signals.

27. (canceled)

30-31. -31. (canceled)

36-39. -39. (canceled)

43. (canceled)

48. (canceled)

50-78. -78. (canceled)

80-84. -84. (canceled)