Bit error performance evaluation of double-differential QPSK in faded channels characterized by Gaussian plus impulsive noise and Doppler effects

A Fourier-Bessel series-based analysis that allows real-time symbol-to-symbol error performance evaluation for mobile radio direct-sequence code division multiple-access (DS-CDMA) systems is described. The technique analyzes mobile radio communication aeronautic links and generates average bit error rate (BER) and bit-to-bit patterns. Various communication systems parameters (e.g., modulation scheme, data rate, signal-to-noise ratio, and receive speed) as well as multiaccess interference (MAI) environments (i.e., Rayleigh-faded channels with Doppler frequency shift) may be specified and permit performance comparison. Additive white Gaussian (AWG) and impulsive /spl epsiv/-mixture type of noise are also considered to be present for the asynchronous and quasi-synchronous DS-CDMA configurations, with both schemes characterized by the incorporation of double-differential QPSK (DDQPSK) modulation. The obtained results demonstrate that the proposed combination in terms of multiplexing and digital modulation may be a suitable alternative solution for air-to-air and/or air-to-ground aeronautic communications for optimized BER versus signal-to-noise ratio system performance and, hence, for "best" channel capacity versus receiver complexity.