Modulated Wideband Converter With Non-Ideal Lowpass Filters

We investigate the impact of using non-ideal lowpass filters in the modulated wideband (MWC) converter, which is a recent sub-Nyquist sampling system for sparse wideband analog signals. We begin by deriving a perfect reconstruction condition for general lowpass filters, which coincides with the well-known Nyquist inter-symbol interference (ISI) criterion in communication theory. Then, we propose to compensate for the non-ideal lowpass filters using a digital FIR correction scheme. The proposed solution is validated by experimental results.