Behavior of slow FH-systems in a multipath environment

We focus on the performance of VHF frequency hopping (FH) radios with different synchronization philosophies, based on a statistical radio channel model which takes into account the propagation mechanisms of a specific area. For the simulation we use a binary frequency shift keying (BFSK) modulation with 20 kbit/sec and a non-coherent matched filter (MF) receiver with maximum likelihood decision. All functional blocks in the communication system are represented in the baseband where the dependence on the carrier frequency is included in the channel model. Due to multipath propagation, the optimum sampling time at the output of the receiver´s MF changes for each carrier frequency and for different receiver positions. The simulation results show the difference in the bit error rate (BER) for a slow FH radio system with different synchronization philosophies