On Simplification of Ray Tracing Channels in Radio Channel Emulators for Device Testing

Emulation of ray tracing (RT) simulated and measured channels in radio channel emulators is seen as a key enabler
for virtual drive testing (VDT). Limitations in emulator hardware
resources require that RT simulated or measured channels are
simplified. In this preliminary study, the impact of channel
simplification is investigated with a target of minimizing the
error of the mean delay. The increase in the number of taps
in the channel model caused by tap splitting in the conventional
constant mean delay method proposed in the literature is addressed by considering the radio frequency (RF) bandwidth of
the channel emulator. Although this approach is not optimal, it
uses on average 8 taps compared to 24 taps and 36 taps in the
original and the tap aligned channels with a constant mean delay,
respectively.