Single-Frequency-Driven Multi-Resonant Fsk: An Easy-to-Operate Wideband Modulation Scheme for Magnetic (Underwater) Communication

In this short paper, an innovative wideband hardware-based frequency shift keying modulation technique for magnetic communication is presented. The easy-to-operate transmitter circuit is designed to switch between two configurable resonant frequencies with precise timing, with data symbols mapped to those frequencies. The implementation of a zero voltage crossing detector ensures precise timing for ideal symbol changes, which retains most of the system's energy. This largely eliminates the transient response and unwanted amplitude fluctuations, so that the symbol rate can be significantly increased in conjunction with a wideband receiver. Due to the efficient operation, the resonant circuit needs to be driven by just one of the data symbol frequencies, which simplifies the signal generation for transmitter operation.