Macro- and micro-diversity in indoor body-to-body channels

Body shadowing and fading effects may severely affect Body Area Networks and, in particular, body-to-body communications. Therefore, in this paper, we investigate the advantages obtained by employing diversity techniques both at macro and micro level. In the first case, multiple antennas are distributed in different parts of the body that may experience different body shadowing. In the second case, we use multiple co-located antennas to overcome fading effects. Measurements were carried out in a typical office environment at the frequency of 2.48 GHz and included different type of body movements. Channel capacity and diversity gain are the metrics used to evaluate the improvement introduced by multiple antenna techniques with respect to the single branch case. Results show that it is possible to achieve gains larger than 10dB at the reliability level of 99% in a four-branch system.