Transform for communication symbols

Abstract

A method is disclosed for transferring data symbols between a transmitter and a receiver. The method comprises specifying communication symbols through application of a transform to a representation of the data symbols, and conveying a signal indicative of the communication symbols from the transmitter to the receiver. When expressed as a transform matrix, the transform has at least the following properties: that a ratio (between number of zero-valued elements of the transform matrix and number of non-zero-valued elements of the transform matrix) equals or exceeds a sparsity threshold, and that a number of columns of the transform matrix that has a zero-valued element sum equals or exceeds an angle distortion mitigation threshold. When the method is performed by the transmitter, the method may further comprise providing the communication symbols by applying the transform to amplitude representations of the data symbols, and conveying the signal indicative of the communication symbols may comprise transmitting the signal. When the method is performed by the receiver, conveying the signal indicative of the communication symbols may comprise receiving the signal, and the method may further comprise estimating the data symbols by applying a reverse operation of the transform to angle representations of the received signal. Corresponding apparatuses, transmitter, receiver, communication device and computer program product are also disclosed.