Development of communication system for a fading channel simulator implementation using Matlab

Consider a single-input and single-output (SISO) communi- cation system where the transmission of in-phase ??(?) and quadrature ??(?) signals modulated by orthogonal carriers ??(?) and ??(?), respectively, are assumed, which are mixed for obtaining ?(?). This signal ?(?) is propagated through the communication channel ?(?, ?), which is considered to be a causal time-varying linear system. The signal filtered by the channel reaches the receiver where a noisy version ?(?) is detected. It can be expressed mathematically as follows: ? (?) = ∫ ∞ −∞ ? (?−?) ? (?, ?) ?? + ? (?), (1) where ?(?) = ??(?)??(?) + ??(?)??(?), and ? is a time variable. The impulse response ?(?, ?) states the response of the channel in the instant ? when a stimulus is applied in ?−?, which reflects the time variability of the channel impulse response. Likewise, ?(?) is the aggregated stochastic noise. This received signal ?(?) is demodulated in order to obtain the in-phase and quadrature signals ??(?) and ??(?).