Towards improving performance of galvanic coupling Intra-Body Communication

This paper investigates how to improve the communication performance of galvanic coupling Intra-Body Communication (IBC). Towards this objective, an in vivo measurement is firstly carried out to obtain the channel characteristics of human body in the frequency range from 100 Hz to 1 MHz. Severe gain variation and phase non-linearity are observed in the frequency response lower than frequency of 200 kHz. Then pulse shaping and channel equalization are introduced for QPSK and 16QAM modulation systems to eliminate the channel impairments in both simulations and experiments. The results show that root raised cosine pulses can significantly reduce Bit Error Rate (BER). Furthermore, the channel equalization improves BER 1-10% for QPSK, and more than 20% for 16QAM. The results indicate pulse shaping and channel equalization are effective ways for BER reduction, which are very important for the design of IBC system.