Performance of antennas in the on-body environment

This paper presents the performance of antenna combinations for on body communications. Several different antennas have been designed and built such as monopole antennas, patch antenna, loop antenna, patch and patch array antennas. These antennas were designed for the operation in the unlicensed ISM band, 2.45 GHz. The antennas then were tested in the on body environment. The performance of the antenna combinations is determined by measuring the path gain between two on-body paths for a range of body postures. Measurement results show that the combination of monopole antennas performs best in most of the measurement cases compared to other combinations. The comparison between calculation and measurement results, which consider the free space loss and antenna gain give results that are within 10dB of measurements for most body postures.