Simulation of bit error performance of FSK, BPSK, and π/4 DQPSK in flat fading indoor radio channels using a measurement-based channel model

The results of a simulation study that provides insight into the simulation methodology and bit error rate (BER) performance of frequency-shift keying (FSK), binary phase-shift keying (BPSK), and π/4 differential phase-shift keying (π/4 DQPSK) in flat fading channels inside open plan buildings are presented. A detailed measurement-based propagation channel model, SIRCIM (simulation of indoor radio channel impulse response models), which generates over 1000 closely spaced baseband equivalent complex impulse responses for a mobile radio operating at 1.3 GHz and traveling over a 1-m path, is used. The small-scale channel model, the communication system models used in the analysis and the methods used to predict BER are described. The channel simulator and the systems models have been thoroughly tested, and results from average instantaneous BER simulations are shown. The BER performances of the modulation techniques are presented. It is found that BPSK offers between a 2.8-dB and 3.0-dB improvement over π/4 DQPSK, although the latter offers a 3-dB increase in capacity for a given spectrum allocation