Performance of tactical VHF FH-radios referring to radio channel measurements

The performance of VHF frequency hopping (FH) radios with different synchronization philosophies and data rates is investigated, based on a statistical radio channel model which takes into account the spatially inhomogeneous distribution of partial waves. The channel parameters are gained from VHF wideband channel measurements in a mountainous terrain. For the simulation we use a binary frequency shift keying (BFSK) modulation with 20 and 80 kbit/sec and a non-coherent matched filter (MF) receiver with a 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 different data rates of a slow FH radio system with and without synchronizing each hop