Design of pulse shaping filters and their applications in radio systems

Partial-response signaling is known as correlative level coding wherein the constraint on waveforms is relaxed so as to allow a controlled amount of ISI. In this paper, the Lagrange multiplier approach, which is easy to incorporate both time- and frequency-domain constraints by minimizing a quadratic measure of the error in the design bands, is applied to design a large class of such digital filters for communication in this paper. Also, the iterative Lagrange multiplier approach combining the Lagrange multiplier approach and a tree search algorithm is proposed for designing discrete coefficient pulse shaping FIR digital filters. System experiments such as an SSB radio system using partial response signaling are demonstrated to present the usefulness of the proposed algorithm.