Abstract
Wireless body area networks (BANs) are attracting much attention due to their suitable for healthcare and medical applications. Unfortunately, electrostatic discharge (ESD) is a major electromagnetic (EM) noise source that can degrade wireless communication performance. In this study, we measure EM noise power in the 2.4 GHz and 30 MHz bands for indirect ESD testing specified in IEC 61000-4-2 standard, and derived a statistical ESD noise model from the measurement results. The ESD noise power was found to follow a lognormal distribution in both 2.4 GHz and 30 MHz bands. We use this ESD noise model to conduct bit error rate (BER) simulations in a communication channel with additive white Gaussian noise (AWGN) plus ESD noise at 2.4 GHz and 30 MHz bands. The result is that the BER performance is virtually the same in both bands, and decreases with the signal to noise power ratio (SNR). It is also shown that an error floor exists in the BER performances at both frequencies, which, if the ESD noise power is larger than the Gaussian noise, cannot be improved by increasing the SNR. Although the ESD noise power at 2.4 GHz band is nearly 30 dB smaller than that at 30 MHz band, the signal attenuation along the human body at 2.4 GHz band is much larger compared to 30 MHz band. This may yield a similar SNR level at 30 MHz and 2.4 GHz bands in an ESD-dominated environment, so that the 2.4 GHz band does not have an obvious merit for BAN applications. Since there are so many in-band interference sources at 2.4 GHz band, the 30 MHz band seems more promising for vital data transmission in a BAN scenario even in an ESD-dominated environment.
