Demonstration of 40 GHz Analog-to-Digital Conversion Using Copy-and-Sample-All Parametric Processing

Direct-phase and amplitude digitalization based on free-space interferometry

“…If a traditional photonic-assisted ADC, e.g. the one surveyed in [9] by Valley (since publication of the survey [9], additional interesting techniques, like [10] by Wiberg et al, have been suggested), were used with the aim of assisting electronics to get better aperture jitter performance, the electronic signal (voltage or current) would be temporarily converted backwards, to optics, to be used as an input for the photonic subsystem in these devices. In optical communications, the benefits of photonic-domain sampling can be used directly.…”

Progress in Photonic Analog-to-Digital Conversion

“…With several decades of research in photonic analog-to-digital converters (ADCs) [1,2], last few years have seen a renewed interest in this technology [3][4][5][6][7], considered as capable of delivering orders-of-magnitude improvement in accurate digitization of high-speed RF signals. The progress in electronic ADC performance is facing two major challenges: aperture jitter of the sampling clock and comparator ambiguity [8].…”

“…With the photonic time-stretch approach [17], the bandwidth of the time-division multiplexed channels is reduced, enabling sampling rates as high as 10 TSa/s [18]. Some recent photonic ADC demonstrations include sampling of a 733 MHz RF tone with 9.8 effective number of bits (ENOB) [19], a 35 GHz tone with 2.5 ENOB [3], 4 GHz with 7.2 ENOB and 10 GHz with 6.65 ENOB [4], 6.5 GHz with 6.65 ENOB and 10 GHz with 6.15 ENOB [5], 40 GHz with 6.0 ENOB [6], and 41 GHz with 7.0 ENOB [7]. What makes these developments especially exciting is that with the recent progress made in silicon photonic and electronic-photonic integration technologies [20][21][22], it becomes feasible to transfer the photonic ADC systems from an optical table to a single silicon chip.…”