METHOD FOR REDUCING INTERFERENCE IN A RADIO NETWORK EQUIPMENT AND EQUIPMENT PERFORMING THE METHOD

• US 20090268792A1
• Filed: 04/23/2009
• Published: 10/29/2009
• Est. Priority Date: 04/24/2008
• Status: Active Grant

• Current Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Original Assignee: Alcatel-Lucent SA (Nokia Corporation)
• Inventors: COLOMBO, Claudio
• Granted Patent: US 9,083,413 B2
• Time in Patent Office: Days
• US Class Current: 375/219
• CPC Class Codes: H04B 1/525 with means for reducing leakage of transmitter signal into the receiver
• CPC Class Codes: H04B 7/0808 comparing all antennas before reception
• CPC Class Codes: H04B 7/10 Polarisation diversity; Directional diversity

Abstract

Method and system for reducing interference between adjacent antennas wherein one antenna transmits a first signal from a transmitter equipment and a second antenna receives a second signal by a receiver equipment, the first and the second signals may have the same frequency, and the angular discrimination between the TX antenna and the RX antenna in the same location is low. The transmitter equipment inputs an intermediate frequency contribution of the first signal into a cross-polar interference canceller, included in the receiver equipment, for reducing a co-channel interference in the receiver equipment caused by the first and the second signals, wherein the cross-polar interference canceller selects a desired signal from the two signals received so as to reduce said interference.

Claims

1. A method for reducing interference between at least two adjacent antennas comprising the steps of:

transmitting a first signal from a transmitter equipment

receiving a second signal by a receiver equipment

inputting the first and the second signal into a cross-polar interference canceller, included in the receiver equipment

calculating a respective power and/or a respective BER of the first and the second signals

selecting between the first signal and the second signal the signal that has its respective power greater than the respective power of the other signal, or the one that has its respective BER lower than the respective BER of the other signal;

or

selecting between the first signal and the second signal the signal that has its respective power greater than the respective power of the other signal and has its respective BER lower than the respective BER of the other signal.

2. The method of claim 1, wherein the first signal and the second signal have respective frequencies being substantially close to each other in value.

3. The method of claim 2, wherein the first and the second signal have the same frequency.

8. A method of claim 1 implemented in a computer program product wherein the program is run on a computer, an ASIC, an FPGA or a microprocessor.

9. A method of claim 1 implemented in a program wherein computer readable storage means has a message therein, such computer readable storage means containing program code means corresponding to the program, and wherein the program is run on a computer, an ASIC, an FPGA or a microprocessor.

4. A receiver equipment adapted for receiving a receive signal from a first antenna and a cross-polar interference signal from a second antenna adjacent to the first antenna, wherein the receiver equipment comprises a cross-polar interference canceller adapted for receiving the receive signal and the cross-polar interference signal the receiver equipment having

means for calculating a respective power and/or a respective BER of the receive signal and the cross-polar interference signal

means for selecting between the receive signal and the cross-polar interference based on said calculated values of respective power, or respective BER individually or in combination.

5. The receiver equipment of claim 4 wherein the receive signal and the cross-polar interference signal have respective frequencies being substantially close to each other in value.

6. The receiver equipment of claim 5 wherein the receive signal and the transmit signal have the same frequency.

7. The receiver equipment of claim 4 wherein the cross-polar interference canceller comprises a at least two branches, each of the at least two branches comprising a mixer and a fractionally spaced equalizer and further comprising a clock unit for providing clock signal to each of the at least two branches and a combiner for combining respective outputs of the fractionally spaced equalizers of the at least two branches.