Radio-frequency (RF) waveform synthesis has broad applications in ultrawide-bandwidth wireless communications, radar systems, and electronic testing. Photonic-based approaches offer key advantages in bandwidth and phase noise thanks to the ultrahigh optical carrier frequency. In this work, we demonstrate Fourier synthesis arbitrary waveform generation (AWG) with integrated optical microresonator solitons. The RF temporal waveform is synthesized through line-by-line amplitude and phase shaping of an optical soliton microcomb, which is down-converted to the RF domain through dual-comb optical coherent sampling. A variety of RF waveforms with tunable repetition cycles are shown in our demonstration. Our approach provides not only the possibility of precise Fourier synthesis at microwave and millimeter-wave frequencies, but also a viable path to fully integrated photonic-based RF AWG on a chip.
This content will become publicly available on December 23, 2023
Electronic analog to digital converters (ADCs) are running up against the well-known bit depth versus bandwidth trade off. Towards this end, radio frequency (RF) photonic-enhanced ADCs have been the subject of interest for some time. Optical frequency comb technology has been used as a workhorse underlying many of these architectures. Unfortunately, such designs must generally grapple with size, weight, and power (SWaP) concerns, as well as frequency ambiguity issues which threaten to obscure critical spectral information of detected RF signals. In this work, we address these concerns via an RF photonic downconverter with potential for easy integration and field deployment by leveraging a novel, to the best of our knowledge, hybrid microcomb/electro-optic comb design.more » « less
- NSF-PAR ID:
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Letters
- 0146-9592; OPLEDP
- Page Range / eLocation ID:
- Article No. 159
- Medium: X
- Sponsoring Org:
- National Science Foundation
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