Indoor ISM band multipath fading: frequency and antenna diversity

The frequency fading characterization of the indoor ISM (902-928 MHz) channel are presented. This includes plots of the frequency-dependence of the fading and calculations of the correlation bandwidth. Finally, the measured diversity performance of three novel dual antenna configurations proposed for an ISM band wireless transceiver handset are presented. The diversity performance of these antenna geometries is assessed by measuring the power correlation coefficient of the signal received over each of the two antennas located on the handset. To evaluate the functionality of the measuring apparatus used in these experiments, the correlations of the received signal from two dipole antennas with various separations are measured, for which theoretically computed and previously measured envelope correlation coefficient data is available. Considerable effort is also directed at extraction of the fast fading information from the observed signal level, and its effect is detailed.