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Tests for the wide-sense stationarity (WSS) of multivariate random processes are developed and applied to measured multiple-input--multiple-output (MIMO) radio channel responses. Evolutionary spectral density functions are used to estimate the time-dependent power spectral density, and analysis of variance procedures are applied to determine whether the first and second moments of the data series exhibit statistically significant changes over short intervals. It is found that while the assumption of WSS is met in 40%-70% of half-second intervals for a single element at the transmitter and receiver, only 2%-12% of intervals with two elements at the transmitter and receiver are jointly WSS; furthermore, the occurrence of non-WSS intervals is not dependent on the antenna separation. The analyses also show that WSS intervals are interspersed with long non-WSS intervals. [ABSTRACT FROM AUTHOR]

This paper presents the results of a measurement campaign conducted in the winter of 2002 around the city of Munich in southern Germany. The primary goal was to evaluate the link performance of the land mobile satellite channel at Ku-band and to characterize the temporal behavior of the channel to help in the evaluation of different fade mitigation techniques for future mobile satellite systems that aim at employing this frequency band. To achieve this objective, first- and second-order channel statistics will be presented, the outage probability of the channel analyzed, and a Markov-chain-based narrowband channel model proposed. [ABSTRACT FROM AUTHOR]