An effective digital demodulation system based on the technique of Ho, Chan and Inko is designed for quadrature demodulation of signals with a linear frequency modulation (LFM). The influence of LFM-signal parameters on the quality of demodulation is studied. Two variants of a sampling frequency are chosen, and a set of lowpass filters for Q-component generation is designed for each variant of a sampling frequency. The quality of demodulation is estimated in terms of absolute amplitude and phase errors evaluated as a function of system parameters. The results obtained in simulations show that the optimal choice of a sampling frequency (48 MHz) enables to reduce the imbalance phase errors to minimum (0.0012°) if the optimal equiripple lowpass filter with only 6 elements is chosen for Q-component generation.
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