Optimisation of modulation fidelity calculations for π/4 DQPSK modulators

This paper presents the development of a novel algorithm for the optimisation of modulation fidelity calculations for π/4 DQPSK baseband modulators. The focus is on modulators used in EIA/TIA IS-136 conforming cellular and digital mobile radio (DMR) systems. The algorithm is based on a new approach to deriving an accurate quantisation of the modulation fidelity. This approach, together with the algorithm´s implementation using DSP techniques suitable for use on automatic test equipment, is described