Modified maximin algorithm for FH system under fading environments

The maximin algorithm of D. Torrieri and K. Bakhru, (see "The Maximin Algorithm for Adaptive Arrays and Frequency-Hopping Systems", ARL-TR-2026, 1999) is a blind adaptive-array algorithm that provides simultaneous interference suppression and beam forming in a frequency-hopping communication system. However, its performance can be severely degraded in the presence of MSK (minimum shift keying) modulated jamming signals in its present state of implementation. We propose a new implementation scheme for the maximin algorithm, which can provide improvements in the rate of convergence even in the presence of MSK modulated jamming signals. Computer simulation results also reveal the robustness of the proposed modification under fading environments. The issue of soft-limiter is also addressed, showing the validity of the proposed implementation.