A variety of soft-decision decoding metrics for slow frequency-hopped, differential phase-shift-keyed spread-spectrum systems are studied. By examining the computational cutoff rates for these metrics, the usefulness of side information, the effectiveness of limiting and quantization when side information is not available, and the importance of a judicious choice of the quantization step size one highlighted. To confirm the validity of the analysis, Monte-Carlo-type simulations for a (7, 1/2)-coded system are conducted, and the resulting bit-error-rates are compared with estimations calculated from two known formulas
Date of Conference: 11-14 Jun 1989