Real-time gap-free dynamic waveform spectral analysis with nanosecond resolutions through analog signal processing

• DOI: 10.1038/s41467-020-17119-2
• Publication Date: 2020-07-03T10:02:47Z
• Authors: Saikrishna Reddy ...; Reza Maram; Luis Romero Cortés; Jun Ho Chang; Leslie Rusch; Sophie LaRochelle; Hugues Guillet de...; José Azaña
• Keywords: Spectrogram; Analog signal processing; Nanosecond

Abstract Real-time tracking of a waveform frequency content is essential for detection and analysis fast rare events in communications, radar, radio astronomy, spectroscopy, sensing etc. This requires method that can provide real-time spectrum (RT-SA) high-speed waveforms continuous gap-free fashion. Digital signal processing inefficient to perform RT-SA over instantaneous bandwidths above the sub-GHz range and/or track spectral changes faster than few microseconds. Analog dispersion-induced frequency-to-time mapping enables short isolated pulse-like signals but cannot be extended waveforms. Here, we propose universal analog approach time-mapping spectrogram −the prime dynamic analysis− an incoming arbitrary waveform, based on simple sampling dispersive delay scheme. In experiments, spectrograms GHz-bandwidth microwave are captured at speed ~5×10 9 Fourier transforms per second, allowing intercept nanosecond-duration transients real time. opens new opportunities