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This paper presents wideband characteristics of a low elevation, land mobile, single satellite, dual circularly polarized, multiple-input multiple-output (MIMO) radio propagation channel. The work is based on S-band measurements using an artificial platform to represent the satellite, situated on a hilltop, to a mobile vehicle located in three environments: tree-lined road, suburban and urban. First and second order statistics and inter-tap cross-correlations are derived for both large and small scale fading, over the delay and combined spatial/polarization domains from the measured 2times2 MIMO matrix channel data. The work is aimed towards further development of a valid wideband land mobile satellite (LMS) MIMO channel model. Such systems may form the next generation of satellite delivered mobile broadband Internet services. [ABSTRACT FROM PUBLISHER]

Movement of vegetation structures introduces an adverse environment for high frequency radiowave propagation. This paper examines a series of vegetation scattering measurement campaigns during various wind conditions. The measurements were divided into controlled and outdoor environments. The controlled environment measurements were conducted in an anechoic chamber at 0.9, 2, 12 and 17 GHz. The outdoor measurements were carried out at 1.8 GHz and involved in recording of a transmitted signal originating from an existing digital cellular system (DCS-1800) base station. The obtained results are discussed and presented in terms of their first- and second-order statistics. Analysis demonstrates that the received signal behaviour is highly wind dependent, especially when the environment is changing from calm to a windy condition. The signal fast-fading is found to be Rician distributed and an empirical model of the k-factor variation over wind speed is also presented. [ABSTRACT FROM PUBLISHER]