Abstract
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.
Research supported under IIT-BAS Grant No 010044, MPS Ltd. Grant, BNF“SR” Grant No I-902/99.
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© 2003 Springer-Verlag Berlin Heidelberg
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Behar, V., Kabakchiev, C. (2003). Digital Quadrature Demodulation of LFM Signals Obtained by Lowpass Filtering. In: Dimov, I., Lirkov, I., Margenov, S., Zlatev, Z. (eds) Numerical Methods and Applications. NMA 2002. Lecture Notes in Computer Science, vol 2542. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-36487-0_29
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DOI: https://doi.org/10.1007/3-540-36487-0_29
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