Js. Colburn et al., EVALUATION OF PERSONAL COMMUNICATIONS DUAL-ANTENNA HANDSET DIVERSITY PERFORMANCE, IEEE transactions on vehicular technology, 47(3), 1998, pp. 737-746
In personal wireless communications systems, multipath propagation has
a significant effect on system design and performance. signal strengt
h fading caused by destructive interference between multiple replicas
of the signal of interest arriving at the receiver over different path
s often is the limiting factor in system range/fidelity. Antenna diver
sity is one technique that can be used to help overcome multipath fadi
ng, This paper presents a description of experiments, data processing,
and results used to evaluate the diversity performance of three candi
date dual-antenna handset configurations: two side-mounted planar-inve
rted F antennas (PIFA's), a back-mounted PIFA with a top-mounted helix
, a top-mounted PIFA, and a ''flip'' monopole. In particular, the indo
or industrial, scientific, and medical (ISM) band (902-928 MHz) propag
ation channel was of interest. These experiments did not include opera
tor proximity effects, and in these tests, the dual-antenna handset re
mained stationary while the transmitter was moved along predetermined
indoor paths. The issue of data normalization for extraction of fast f
ading behavior from measured data will be addressed, with results show
ing its effect on observed correlation presented. Also, measured indoo
r fading distributions are presented and seen to fit the Rician and Ra
yleigh models well, From the diversity results presented, it is seen t
hat the three proposed dual-antenna handsets yield sufficient decorrel
ation to warrant consideration for use in diversity systems.