IF digital generation of FMCW waveforms for wideband channel characterisation
Sana Salous · IEE Proceedings I Communications Speech and Vision · 1992
Digital generation methods of FMCW signals include frequency synthesis and direct waveform synthesis. The signal can be either generated directly at IF or from its baseband components which are combined by a SSB modulator. The IF signal is subsequently upconverted to RF. In this paper the different generation methods at IF, and a number of upconversion methods are described. A simplified digital technique for combining the baseband components to produce a signal at IF is presented. Application to wideband characterisation of the mobile radio channel is illustrated by a simulation example. Finally, a comparison with PRBS sounders demonstrates the advantages of FMCW sounders which employ heterodyne detection.