Wideband characterisation of the high elevation orbit satellite-mobile channel at L-band

The authors discuss the Archimedes project for wideband channel characterisation. Implicit in the use of Archimedes for a BSS{S} or advanced LMSS are digital modulation schemes at relatively high data rates. In mobile radio channels, multipath propagation produces frequency selective fading effects, this means that the bandwidth of the transmitted signal over which a reasonable degree of correlation in channel variations occurs is limited. For digital systems the problem manifests itself as intersymbol interference (ISI). So, at the frequencies under consideration the main requirement is to know the bandwidth of a signal propagating in the channel over which there should be little ISI. This information is obtained by wideband channel sounding, methods for which are discussed. The experiment is discussed in detail