Orthogonal digital waveform set design for multiaccess communications systems

Abstract

This paper proposes a new approach for the design of a set of digital filters which can be used as message-carrying waveforms in multicarrier communication systems. The filter set design problem is formulated as a constrained nonconvex optimization problem. For bandwidth efficiency, all the digital filters in the set are constrained to have approximately the same desired spectral shapes in a prescribed passband; To minimize intersymbol interference and co-channel interference, all the digital filters in the set are constrained to have low values of cross-correlation at all lags and low values of auto-correlation at nonzero lags. Methods for solving the proposed nonconvex optimization problem are outlined. Numerical results are presented to illustrate the usefulness of the proposed approach.