I hear about equipment supporting Matrix A and Matrix B. What does that mean?
MIMO techniques can be used under different circumstances to achieve increased capacity, reliability, range and coverage. A logical design should include all these features in an adaptive manner. In WiMAX systems MIMO Matrix A refers to the Space Time Block Coding (STBC) technique and MIMO Matrix B refers to the Spatial Multiplexing (SM) technique. In Matrix A, a single data stream is transmitted as multiple redundant data streams orthogonal to each other. This increases the probability that the receiver will identify a strong signal even in the presence of physical path loss. On the other hand, Matrix B will split the signal and transmit each data stream from a different antenna element orthogonal to each other. This technique sends more information in the same time-frequency resource allocated to it, counting on multi-path to ensure that the streams arrive with sufficient delay between them for the receiver to discern the separate spatial signature. Where SNR is high, this approach g
