Diversity in short range digital systems

The authors investigate the relationship between the irreducible bit error rate, the data rate and the RMS delay spread for a binary digital FM system. The use of diversity, as a method to reduce the impact of multipath fading, is also described. In particular, the use of switched diversity has been explored via computer simulation. The results obtained from this simulation have shown that, for an error threshold of 0.1%, two branch diversity yields an approximate three fold increase in the maximum data rate. Further improvements are also possible when higher levels of diversity are used. These improvements indicate that for short range mobile communications diversity may be considered, up to a point, as an effective alternative to channel equalisation