hes enable simple modelling of short-term fading in theoretic capacities. Central to these techniques, multi- both time and frequency domains. RT approaches, being ple antennas are employed at both the BS and the MT in site specific, are numerical intensive techniques. order to exploit the multipath richness of the propaga- Since the knowledge of the mean level of the received tion channel. One way to achieve this is to separate the signal in a multipath environment, and of its variations antenna elements at both the BS and the MT, SO that around the mean, is fundamental when designing a wire- large diversity orders can be achieved. This requires an- less communications system, it should be properly tenna spacings of up to tens of wavelengths at the BS and assessed if different techniques are appropriate for up to a wavelength at the MT. Employing multiple an- evaluating such variations. From the work in [ThYo03], it tennas at the BS does not present a significant problem, is shown that RT techniques make it possible to estimate but accommodating more antennas at the MT introduces with sufficient accuracy not only the mean signal level several constraints for practical implementation. but also its variations about the mean, therefore allowing In this regard, the Electromagnetic Vector Sensor to evaluate its statistics, at least in indoor environments. (EVS) can be deployed as a compact MIMO receiver The capacity to calculate the mean power and the local antenna capable of measuring six time varying electric statistics of the received signal leads to some optimism fields, and magnetic fields, at a point in space, Figure 4.7- over the possibility of obtaining site specific channel 35. Though the EVS has been widely used for direction models, which can account for the channel variations in finding applications [NePa94], [WoZo00], recent results different locations inside an area of interest. Further- show that EVS can be applied to mobile communication more, starting from the Doppler spectrum at one single systems, 