Multi-user multi-stream beamforming method, apparatus, and base station

A multi-user multi-stream beamforming apparatus, comprising:

• a beamforming matrix calculating unit configured to calculate a beamforming matrix of each user in the multi-user according to a minimum leakage principle;
• a user average SLNR calculating unit configured to determine a user average SLNR of the multi-user according to the beamforming matrix of each user;
• and
• a user average SLNR stableness judging unit configured to determine whether the user average SLNR is stable,
• wherein if the user average SLNR is not stable, the beamforming matrix calculating unit recalculates the beamforming matrix of each user by using the calculated beamforming matrix of each user;
• wherein the apparatus further comprises an iteration judging unit configured to judge whether the user average SLNR stableness judging unit has performed a predetermined number of determinations, or whether the beamforming matrix calculating unit has performed a predetermined number of calculations of the beamforming matrix of each user, and end the processing if the predetermined number of determinations or the predetermined number of calculations of the beamforming matrix of each user have been performed.

A multi-user multi-stream beamforming apparatus, comprising:

• a beamforming matrix calculating unit configured to calculate a beamforming matrix of each user in the multi-user according to a minimum leakage principle;
• a user average Signal to Leakage Noise Ratio (SLNR) calculating unit configured to determine a user average SLNR of the multi-user according to the beamforming matrix of each user;
• and
• a user average SLNR stableness judging unit configured to determine whether the user average SLNR is stable, wherein if |SLNR(i)−SLNR(i−1)|≦δ (δ is a predetermined number), then it is judged that the user average SLNR is stable, where i represents a number of iterations, SLNR(i) represents a user average SLNR obtained at the ith iteration;
• wherein if the user average SLNR is not stable, the beamforming matrix calculating unit recalculates the beamforming matrix of each user by using the calculated beamforming matrix of each user;
• wherein the beamforming matrix calculating unit comprises:
• an initial received-merged matrix calculating unit configured to determine an initial received-merged matrix of each user in the multi-user;
• an updated received-merged matrix calculating unit configured to determine an updated received-merged matrix of each user according to the previously calculated beamforming matrix of each user;
• a singular solution calculating unit configured to calculate a singular solution based on the initial received-merged matrix or the updated received-merged matrix of each user according to the minimum leakage principle;
• and
• a beamforming matrix determining unit configured to determine a beamforming matrix of each user by using the singular solution
• a retransmitted data stream judging unit configured to judge whether there is a data stream to be retransmitted with respect to each user in the multi-user;
• and
• an optimized beamforming vector allocating unit configured to select, when the retransmitted data stream judging unit judges that a user requires a data stream to be retransmitted, a beamforming vector corresponding to a channel having good channel quality from the beamforming matrix of the user and allocate to the data stream.

A multi-user multi-stream beamforming apparatus, comprising:

• a beamforming matrix calculating unit configured to calculate a beamforming matrix of each user in the multi-user according to a minimum leakage principle;
• a user average SLNR calculating unit configured to determine a user average SLNR of the multi-user according to the beamforming matrix of each user;
• and
• a user average SLNR stableness judging unit configured to determine whether the user average SLNR is stable,
• wherein if the user average SLNR is not stable, the beamforming matrix calculating unit recalculates the beamforming matrix of each user by using the calculated beamforming matrix of each user;
• wherein the apparatus further comprises an iteration judging unit configured to judge whether the user average SLNR stableness judging unit has performed a predetermined number of determinations, or whether the beamforming matrix calculating unit has performed a predetermined number of calculations of the beamforming matrix of each user, and end the processing if the predetermined number of determinations or the predetermined number of calculations of the beamforming matrix of each user have been performed
• a retransmitted data stream judging unit configured to judge whether there is a data stream to be retransmitted with respect to each user in the multi-user;
• and
• an optimized beamforming vector allocating unit configured to select, when the retransmitted data stream judging unit judges that a user requires a data stream to be retransmitted, a beamforming vector corresponding to a channel having good channel quality from the beamforming matrix of the user and allocate to the data stream.