ECES 719: Wireless Communications

This project explores the important aspect of accurate computer simulation of Rayleigh faded envelopes for flat fading channels. In class, we discussed the original sum-of-sinusoids (SOS) model for 2D isotropic scattering around the mobile station (MS) as developed by Jakes [1]. Unfortunately, the statistics of the in-phase and quadrature components of the resultant channel, gI(t) and gQ(t), as well as the envelope, α(t), do not agree well with theory. Several authors [3, 4, 5, 6] have analyzed the statistical properties of Jakes’ simulator in terms of first and second order statistics and wide-sense stationarity and noted important deficiencies. As a consequence, improved SOS simulators have been developed [7, 8, 9, 10, 11, 12] for isotropic scattering around the MS. You will be investigating these simulators for your project. The scenario for simulating the received multipath-faded waveform at the base station (BS) has not been considered in our discussions so far. In general, the BS is located above its surroundings so that there are effectively no local scatterers around the BS. Thus, the scattering as seen by the BS is non-isotropic [1] and the desired characteristics of the faded envelope change with respect to those at the MS. Fortunately, some work has been carried out to modify Jakes’ simulator for generating the faded envelope at a BS [13]. You will be investigating one such approach in the second part of this project.