High data rate closed loop MIMO scheme combining transmit diversity and data multiplexing
View Patent ↗Closed loop multiple-antenna wireless communications system with antenna weights determined by maximizing a composite channel signal-to-interference-plus-noise ratio minimum. Multiplexed symbol streams over subsets of antennas enhance throughout.
1. A wireless transmitter comprising:
A. a symbol mapping circuitry having a data symbol output;
B. a serial to parallel circuitry having an input coupled with the data symbol output and having plural symbol stream outputs;
C. multiplier circuits, one for each symbol stream output, each multiplier circuit having an symbol input, an antenna weight input, and an output, the symbol input being coupled with a symbol stream output;
D. antenna units, each coupled with the output of one multiplier circuit; and
E. an antenna weight circuitry having plural antenna weight outputs, each antenna weight output being coupled with one antenna weight input, the antenna weight circuitry producing weight signals on the antenna weight outputs in accordance with rectangular matrix that corresponds to a diagonal M.times.M block matrix of (P by M).times.1 vectors, where each (P by M).times.1 vector corresponds to weights for each symbol stream, where P represents a number of antennas and M represents symbol stream outputs.
2. The wireless transmitter of claim 1 in which each antenna unit P has two antennas.
3. The wireless transmitter of claim 1 in which the serial to parallel circuitry has M symbol stream outputs s m .
4. The wireless transmitter of claim 1 in which each antenna weight is a 2×1 weighting vector w m corresponding to the symbol stream output.
5. The wireless transmitter of claim 1 in which each antenna weight is a vector w m corresponding to the symbol stream output, and in which the antenna weight circuitry provides weight signals in accordance with a weighting matrix V, where:
V
w
1
0
…
0
0
w
2
…
0
⋮
⋮
⋮
⋮
0
0
…
w
m
where each vector w m belongs to a set of (P by M)×1 vectors.
6. The wireless transmitter of claim 1 in which the transmitter is included in user equipment.
7. The wireless transmitter of claim 1 in which the transmitter is included in a mobile device.