In high-speed digital mobile communication, performance is degraded in the
case of multiple delayed waves with a large delay time difference. Spatial-
domain path diversity has been proposed as a means to utilize effectively t
he multiple wave signal power and to compensate the distortion. In this met
hod, an adaptive array with multiple wave vectors is used so that the incid
ent multiple propagation waves are separated and are combined after alignin
g the delay time. However, it may be found that the performance is degraded
since the multiple waves may contain a propagation wave with a small time
difference. This paper considers a means of remedy for such cases and propo
ses the weighted combining method, considering the signal power of the mult
iple waves and the error power in the adaptive array. As a result, in envir
onments where the incidence angles are close enough to produce degradation,
it is seen that the proposed method can greatly improve the BER performanc
e compared to conventional equal-gain combining. (C) 2001 Scripta Technica.