Performance Comparison between Comb Spectrum Modulation and Frequency Hopping in Scatter Communication

The communication channel in atmospheric scatter communication is a typical multipath fading channel, where the received signal experiences severe fading. To mitigate channel fading, diversity techniques must be employed. Traditionally, a common solution involves obtaining spatial diversity gain through multiple antennas, but this approach comes with high algorithmic and device complexity. A relatively new solution to this problem is based on frequency hopping communication methods. This method achieves better diversity gain compared to traditional methods at low data rates, although its performance tends to be average in high data rate systems. This paper proposes a novel communication method based on comb spectrum modulation. Leveraging the sparse characteristics of comb spectrum signals, this method can achieve superior frequency diversity gain.