  We propose a novel random triggering based modulated wideband compressive
sampling (RT-MWCS) method to facilitate efficient realization of sub-Nyquist
rate compressive sampling systems for sparse wideband signals. Under the
assumption that the signal is repetitively (not necessarily periodically)
triggered, RT-MWCS uses random modulation to obtain measurements of the signal
at randomly chosen positions. It uses multiple measurement vector method to
estimate the non-zero supports of the signal in the frequency domain. Then, the
signal spectrum is solved using least square estimation. The distinct ability
of estimating sparse multiband signal is facilitated with the use of level
triggering and time to digital converter devices previously used in random
equivalent sampling (RES) scheme. Compared to the existing compressive sampling
(CS) techniques, such as modulated wideband converter (MWC), RT-MWCS is with
simple system architecture and can be implemented with one channel at the cost
of more sampling time. Experimental results indicate that, for sparse multiband
signal with unknown spectral support, RT-MWCS requires a sampling rate much
lower than Nyquist rate, while giving great quality of signal reconstruction.
