FANDOM


We consider a precoded multiple-antenna broadcast system which consists of a AP with $ N_t $ transmit antennas and $ K $ users each with single receiver antenna. Then, the received signal at user $ k $ is described as

$ y_k = \mathbf{h}_k^T\mathbf{x}+n_k, \quad k=1,2, \ldots, K $

where $ \mathbf{x} = \sum_{i=1}^K s_i P_i \mathbf{w}_i $ is the $ N_t \times 1 $ vector of transmit symbols, $ n_k $ is the noise signal at user $ k $ respectively, $ \mathbf{h}_k $ is the $ N_t \times 1 $ vector of channel coefficients and $ \mathbf{w}_i $ is the $ N_t \times 1 $ linear precoding vector.