PERFORMANCE OF DIVERSITY COMBINING SCHEME USING SIMPLIFIED WEIGHTING FACTOR

Maximal-ratio combining (MRC), which maximizes the carrier to noise ra tio (CNR) of the combined signal, generally requires envelope detectio n and multiplication having linear characteristic over a wide dynamic range to generate a weighting factor for each branch. In this paper, w e propose a simplified two-branch diversity combining scheme without l inear envelope detection. The proposed scheme, called ''level comparis on weighted combining (LCWC),'' is simplified in a manner that its wei ghting factor for each branch is generated from hard-decision results of comparing signal envelopes between two branches. Performance of LCW C is evaluated by computer simulation and laboratory experiment, which shows that its diversity gain is almost identical to that of MRC in a Rayleigh fading channel.