SYSTEMS AND METHODS FOR REDUCING INTERFERENCE IN DATA COMMUNICATION NETWORKS

• US 20140187276A1
• Filed: 01/02/2014
• Published: 07/03/2014
• Est. Priority Date: 01/02/2013
• Status: Active Grant

• Current Assignee: Ubiqam Ltd.
• Original Assignee: Ubiqam Ltd.
• Inventors: CYZS, Baruch, MEIR, Amir, AMIDAN, Oren, MANOR, Daniel
• Granted Patent: US 9,197,344 B2
• Time in Patent Office: Days
• US Class Current: 455/501
• CPC Class Codes: H04B 17/12 of transmit antennas, e.g. of the amplitude or phase
• 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 7/024 Co-operative use of antennas of several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
• 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: H04W 52/243 taking into account interferences

Abstract

A computer-implemented method for calculating interference reducing parameters for cancelling wireless signal interference within a data communication network, comprising: per each of a plurality of antennas of a multi-sector hub communicating with a data communication network and with a corresponding transceiver of a plurality of distant transceivers: calculating a plurality of calibration factors based on values extracted from sequential transmission and reception of predetermined signals between each of the plurality of antennas of the multi-sector hub; calculating at least one receive interference cancellation parameter, to isolate desired signals transmitted by the corresponding distant transceiver from the undesired interference signals transmitted by other non-corresponding distant transceivers; calculating at least one transmit interference parameter for each non-corresponding antenna of the hub, based on the calculated receive interference cancellation parameters and the calibration factors; and generating the interference parameters for applying during operation of the multi-sector hub to generate interference cancellation signals.

Claims

1. A computer-implemented method for calculating interference reducing parameters for cancelling wireless signal interference within a data communication network, the method being carried out by a calibration unit programmed to carry out the steps of the method, which comprise:

per each of a plurality of antennas of a multi-sector hub communicating with a data communication network and with a corresponding transceiver of a plurality of distant transceivers;

calculating a plurality of calibration factors based on values extracted from sequential transmission and reception of predetermined signals between each of the plurality of antennas of the multi-sector hub;

calculating at least one receive interference cancellation parameter, to isolate desired signals transmitted by the corresponding distant transceiver from the undesired interference signals transmitted by other non-corresponding distant transceivers;

calculating at least one transmit interference parameter for each non-corresponding antenna of the hub, based on the calculated receive interference cancellation parameters and the calibration factors; and

generating the interference parameters for applying during operation of the multi-sector hub to generate interference cancellation signals.

2. The computer-implemented method of claim 1, wherein the at least one transmit interference cancellation parameters are calculated from the at least one receive interference cancellation parameters by the equations:

3. The computer-implemented method of claim 1, further comprising performing a calibration process at the multi-sector hub for determining the calibration factors for calculating the transmit interference cancellation parameter from the received interference cancellation parameter.

4. The computer-implemented method of claim 3, wherein the calibration processes comprises:

per each antenna of the multi-sector hub;

transmitting a predefined signal from the respective antenna;

receiving the transmitted predefined signal at other antennas; and

calculating the calibration factors from relationships between the transmitted and received predetermined signals.

5. The computer-implemented method of claim 3, wherein the calibration factors are calculated using the equations:

6. The computer-implemented method of claim 3, wherein the calibration process is occasionally repeated during network operation to update the calibration factor.

7. The computer-implemented method of claim 3, wherein the calibration process is performed at the multi-sector hub independently of the distant transceivers.

8. The computer-implemented method of claim 3, further comprising monitoring a remaining interference level at the multi-sector hub, and repeating the calibration process when the remaining interference level has increased above a predefined threshold.

9. The computer-implemented method of claim 1, wherein there are three distant transceivers and three antennas of the multi-sector hub, the receive interference cancellation parameter for signals transmitted by the second distant transceiver and received by the first antenna, is denoted by w_21r and calculated by the equation:

10. A system for cancelling interference within a communication network comprising:

a multi-sector hub with a plurality of antennas for wireless communication;

a plurality of distant transceivers, the hub antennas and corresponding distant transceivers arranged to form wireless data communication links within a data communication network, wherein signals transmitted by the distant transceivers overlap so that each hub antenna receives signals from the corresponding distant transceiver and at least one non-corresponding distant transceivers, and wherein signals transmitted by the hub antennas overlap so that each distant transceiver receives signals from the corresponding hub antenna and at least one non-corresponding hub antennas;

a hardware processor in electrical communication with each multi-sector hub antenna;

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

modules for calibration;

a module for receiving from the data communication network, a desired signal for wireless transmission by the respective antenna of the multi-sector hub;

a module for calculating a plurality of calibration factors based on values extracted from transmission and reception of predetermined signals between each of the plurality of antennas of the multi-sector hub;

a module for calculating at least one receive interference cancellation parameter, to isolate desired signals transmitted by the corresponding distant transceiver from the un-desired interference signals transmitted by other non-corresponding distant transceivers;

a module for calculating at least one transmit interference parameter for each non-corresponding antenna of the hub, based on the calculated receive interference cancellation parameters and the calibration factors;

modules for operation;

a module for applying the calculated transmit interference cancellation parameters to the desired signal to generate interference cancellation signals for each of the other non-corresponding antennas; and

a module for transmitting the desired signal by the corresponding antenna, and transmitting each interference cancellation signal by each of the other non-corresponding antennas, so that signals received by distant transceivers cancel out to isolate the desired signal.

11. The system of claim 10, wherein all processing for interference cancellation is performed by the processor in electrical communication with the antennas of the multi-sector hub.

12. The system of claim 10, wherein wireless links between the distant transceivers and multi-sector hub antennas operate at the same frequency, or at adjacent frequencies.

13. The system of claim 10, wherein the calibration factor is calculated based on properties of the components of the respective multi-sector hub antennas.

14. The system of claim 10, further comprising one or more additional antennas per multi-sector hub, the plurality of antennas and distant transceivers arranged for multiple-input-multiple-output (MIMO) in a plurality of sectors, wherein signals generated by a subset of one or both of the plurality of antennas and distant transceivers interfere with each other, and wherein a module applies the calibration factors to cancel out signal interference between the plurality of antenna hubs and distant transceivers.

15. The system of claim 10, further comprising one or more additional transceivers per distant transceiver, the hub antennas and plurality of distant transceivers arranged for multiple-input-multiple-output (MIMO) in a plurality of sectors, wherein signals generated by a subset of one or both of the plurality of antennas and distant transceivers interfere with each other, and wherein a module applies the calibration factors to cancel out signal interference between the plurality of antenna hubs and distant transceivers.

16. The system of claim 14, wherein a calibration process for determining calibration factors for calculating the transmit interference cancellation parameters from the receive interference cancellation parameters, is run between each transmission antenna and each receiving antenna that receives interfering signals from other transmission antennas.

17. The system of claim 10, wherein the hub antennas and distant transceivers are arranged as sectors in a multi-point to single-point wireless backhaul for a Long Term Evolution (LTE) network.

18. The system of claim 10, wherein the hub antennas and distant transceivers are arranged as sectors in a multi-point to single-point wireless access network.

19. The system of claim 10, wherein interference cancellation is performed with N antennas of the multi-sector hub for N−

1 distant transceiver interferers.

20. A computer-implemented method for cancelling wireless signal interference within a data communication network, the method being carried out by an interference cancellation unit programmed to carry out the steps of the method, which comprise:

per each of a plurality of antennas of a multi-sector hub communicating with a data communication network and with a corresponding transceiver of a plurality of distant transceivers;

receiving from the data communication network, a desired signal for wireless transmission by the respective antenna of the multi-sector hub;

applying transmit interference cancellation parameters to the desired signal to generate interference cancellation signals for each of the other non-corresponding antennas; and

transmitting the desired signal by the corresponding antenna, and transmitting each interference cancellation signal by each of the other non-corresponding antennas, so that signals received by distant transceivers cancel out to isolate the desired signal;

wherein;

at least one transmit interference parameter for each non-corresponding antenna of the hub is based on receive interference cancellation parameters and calibration factors based on values extracted from sequential transmission and reception of predetermined signals between each of the plurality of antennas of the multi-sector hub, the receive interference cancellation parameters based on isolating desired signals transmitted by the corresponding distant transceiver from the un-desired interference signals transmitted by other non-corresponding distant transceivers.

21. The computer-implemented method of claim 20, further comprising:

receiving at the respective hub antenna desired signals transmitted by the corresponding distant transceiver of the plurality of distant transceivers and undesired signals interfering with the desired signals and transmitted by at least one other non-corresponding of the plurality of distant transceivers;

applying receive interference cancellation parameters to cancel the interference from the signals transmitted by the at least one other non-corresponding of the plurality of distant transceivers to isolate the desired signals from the undesired signals; and

providing the isolated desired signals for transmission within the data communication network.

22. The computer-implemented method of claim 21, wherein each of the receive interference cancellation parameters are applied so that for each undesired signal transmitted by the other non-corresponding distant transceivers, and received by the plurality of hub antennas, the sum of the combination of the received signals having the applied receive interference cancellation parameters is minimized.

23. The computer-implemented method of claim 21, wherein the receive interference cancellation parameters are weights applied to the received signals.