Patent attributes
The present invention provides a MIMO transmission method for discrete modulated signals. The method is mainly characterized in maximizing the mutual information of symbol vectors of a transmitter and a receiver by joint optimization of a source distribution and a precoding matrix. When the current precoding matrix G is determined, the distribution of source multi-dimensional vectors x is maximized by a Lagrange multiplier method to maximize a source entropy; and when the distribution of the current source multi-dimensional vectors x is determined, the precoding matrix G is optimized by a gradient descent method to maximize the mutual information of the transmitted and received vectors. The transmission rate approximates the Shannon limit under a MIMO scenario by joint optimization of the source distribution and the precoding matrix. After the transmitter determines a marginal distribution of symbols of each channel, a non-uniform modulation is performed by using a probabilistic amplitude shaping technology.