Time-stretched short-time Fourier transform

Dept. of Electr. Eng., Univ. of California, Los Angeles, CA, USA
IEEE Transactions on Instrumentation and Measurement (Impact Factor: 1.71). 05/2006; DOI: 10.1109/TIM.2006.864246
Source: IEEE Xplore

ABSTRACT The authors propose and demonstrate the time-stretched short-time Fourier transform (TS-STFT) technique to overcome the limitation of an analog-digital converter (ADC) in the time-frequency analysis of ultrafast signals. Experimentally, the time-frequency analysis of highly chirped RF signals, with a chirp rate as high as 350 GHz/ns, is demonstrated. An effective real-time sampling rate of 320 GSa/s is achieved. Time stretching enhances the analog bandwidth and the effective sampling rate of the ADC and enables measurement of the instantaneous behavior of highly nonstationary ultrawideband signals.