Radio Channel Emulation for Virtual Drive Testing with Site-Specific Channels
Allan Wainaina Mbugua, Yun Fei Chen, Wei Fan · 2022
Virtual drive testing (VDT) with measured or ray tracing (RT) simulated channels requires the simplification of the channel to match the hardware specification of radio channel emulators. That is, reduction of the number of multipath components (MPC)s and adjustment of the arbitrary delays of the MPCs to the sampling grid of the radio channel emulator. In this paper, a fractional delay (FD) filter approximated by a general least square (GLS) finite impulse response (FIR) filter is used for band-limited interpolation to align the delay of the MPCs to the sampling grid of the radio channel emulator. A dominant power selection strategy is then employed to reduce the taps to match a given hardware specification. The GLS FIR method is shown to have superior performance in preservation of the channel frequency response (CFR) compared to rounding delays to the nearest integer multiple of the sampling time.