Modeling of Digital Communication Systems Using SIMULINK

Chapter 6Digital Communications BER Performance in AWGN (BPSK in Fading)

6.1 BPSK in Rayleigh and Rician Fading

This chapter presents several topics in Simulink based on BPSK modulation in fading channels. Specifically these topics include the following:

• BPSK BER performance in Rayleigh fading
• BPSK BER performance in Rician fading
• BPSK BER performance in Rician fading with Multipath
• Rician channel fading characteristics

6.2 BPSK BER Performance in Rayleigh Fading

Prior chapters have introduced Simulink models at the outset to acquaint the reader with important techniques for Simulink model development. Here it is useful to review the theoretical BER performance for Rayleigh fading channels in order to establish a framework for Simulink model construction. Appendix 6.A presents a short review of BPSK BER performance in Rayleigh fading. The error probability for BPSK in Rayleigh fading is given by

where is the average SNR/bit. The time-varying nature of the channel is also characterized by its power spectral density . A specific model referred to as the Jakes model is given by

where is the maximum Doppler frequency.¹ In a mobile channel where a vehicle moves at a speed of ...