Using antenna pooling to enhance a MIMO receiver augmented by RF beamforming

• US 8,923,448 B2
• Filed: 08/29/2013
• Issued: 12/30/2014
• Est. Priority Date: 05/29/2012
• Status: Expired due to Fees

• Current Assignee: Magnolia Broadband Incorporated
• Original Assignee: Magnolia Broadband Incorporated
• Inventors: Kludt, Kenneth, Abreu, Eduardo, Harel, Haim
• Primary Examiner(s): NEFF, MICHAEL R
• Application Number:
  US14/013,190
• Publication Number:
  US 20130343493A1
• Time in Patent Office: 488 Days
• Field of Search: 375/340, 375/316
• US Class Current: 375/340
• CPC Class Codes: H04B 7/0413 MIMO systems
• 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: H04B 7/0874 using subgroups of receive antennas

Abstract

A system having a multi-layer (multi-stream) multiple-input-multiple-output (MIMO) receiving system, having a MIMO baseband module and a radio distribution network (RDN) connected to the MIMO receiving system. The RDN has two or more beamformers that are fed by two or more antennas, so that a total number of antennas in the system are greater than the number of branches of the MIMO baseband module. Each of the beamformers combines RF signals coming from the antennas. The system further implements an antenna routing module that swaps antennas between different beamformers according to one or more qualitative indicators derived from the baseband module, thus increasing the probability of grouping antennas that have lower conflicts between best phases of different layers'"'"' transmitted signals. The system increases the range of antenna selection beyond the set of antennas available for each beamformer.

Claims

1. A system comprising:

a multiple-input-multiple-output (MIMO) receiving system comprising a MIMO baseband module having N branches;

a radio distribution network (RDN) connected to the MIMO receiving system, the RDN comprising at least two beamformers, wherein each of the beamformers is fed by two or more antennas, so that a total number of antennas in the system is M, wherein M and N are integers and M is greater than N, wherein each of the beamformers includes at least one combiner configured to combine signals coming from the antennas feeding the respective beamformer into a combined signal; and

an antenna routing module configured to swap at least one pair of antennas, each of the antennas in the at least one pair being associated with a different beamformer,

wherein said antenna routing module is configured to swap said at least one pair of antennas based on at least one qualitative indicator derived from the baseband module, and

wherein the antenna routing module is configured to route a subset of the antennas with respect to corresponding beamformers by a switching matrix that is dynamically adjusted according to the at least one qualitative indicator, wherein the at least one qualitative indicator comprises a combined power of all beamformers.

2. The system of claim 1, wherein the at least one swapped pair of antennas is selected to increase a diversity gain of the MIMO receiving system.

3. The system of claim 1, wherein the at least one swapped pair of antennas is selected with respect to at least one of signal phases and signal amplitudes.

4. The system of claim 1, wherein the at least one swapped pair of antennas is selected according to a specified antenna signal weighting.

5. The system of claim 1, wherein the combined power of all beamformers, PWR_TOTAL, is defined as:

6. A method of improving reception by a multiple-input-multiple-output (MIMO) receiving system comprising a MIMO baseband module having N branches and a radio distribution network (RDN) connected to the MIMO receiving system, the method comprising:

associating at least two beamformers with the RDN, each of the beamformers including at least one corresponding combiner;

feeding each of the beamformers by two or more antennas, so that a total number of antennas in the system is M, wherein M and N are integers and M is greater than N,

configuring each combiner to combine signals coming from the antennas feeding the corresponding beamformer into a combined signal;

swapping at least one pair of antennas, each of the antennas in the at least one pair being associated with a different beamformer, based on at least one qualitative indicator derived from the baseband module; and

routing a subset of the antennas with respect to corresponding beamformers by a switching matrix that is dynamically adjusted according to the at least one qualitative indicator, wherein the at least one qualitative indicator comprises a combined power of all beamformers.

7. The method of claim 6, wherein the at least one swapped pair of antennas is selected to increase a diversity gain of the MIMO receiving system.

8. The method of claim 6, further comprising selecting the at least one swapped pair of antennas with respect to at least one of signal phases and signal amplitudes.

9. The method of claim 6, further comprising selecting the at least one swapped pair of antennas according to a specified antenna signal weighting.

10. The method of claim 6, wherein the combined power of all beamformers, PWR_TOTAL, is defined as: