Performance Aspects of Alamouti STBC for MIMO Channels Affected by Impulsive Noise

In general, wireless communications are affected by noise and by time-varying characteristics of propagation environment. Space-time block codes are an effective method to combat fading and also to provide spatial diversity. Besides fading and additive white Gaussian noise (AWGN), we considered two types of impulsive noise described by Middleton Class-A (AWCN) and symmetric α-stable (SαS) distributions. The AWCN model was used to highlight the Alamouti code diversity, compared with the situation when the channel is only affected by AWGN. Even in the presence of non-Gaussian noise, the diversity at both the reception and transmission has decreased the number of errors. Alamouti 2 × 2 performances for all three types of aforementioned noise are presented; the evaluation was performed considering the Bit Error Rate (BER) curves depending on signal-to-noise ratio. We have also used this code in image transmission in the presence of SαS noise. For all simulations, data was binary phase-shift keying (BPSK) modulated and the fading was Rayleigh type. Different values of the parameters that describe the noise models were considered.