Simulation of bit error performance and outage probability of π/4 DQPSK in frequency-selective indoor radio channels using a measurement-based channel model

A real-time simulation tool called BERSIM is developed and used to study bit-by-bit errors, average bit error rate and block outage probabilities for π/4 differential quadrature phase-shift keying (DQPSK) at megabit rates with raised-cosine pulse shaping. Simulation results show that when the ratio of RMS delay spread to bit duration is greater than about 0.02, the irreducible average BER is not only a function of RMS delay spread, but is also a function of the temporal and spatial distribution of individual multipath components in the complex channel impulse response. The results show that fading caused by multipath cancellation is the major error mechanism over a local area for RMS delay spreads smaller than 0.02-b duration. An example of BERSIM´s real time output is shown for the transmission of a video image through a mobile radio system. The simulation methods are suited for evaluation and design of indoor wireless LANs, as well as paging and cellular systems