Journal: Light, Science & Applications
Article Title: Optical arbitrary waveform generation (OAWG) using actively phase-stabilized spectral stitching
doi: 10.1038/s41377-025-01937-4
Figure Lengend Snippet: a Optical spectra of 16QAM signals with symbol rates ranging from 80 GBd to 320 GBd generated using spectrally sliced OAWG and measured using a high-resolution optical spectrum analyzer (AP2060, Apex Technologies, Marcoussis, France, resolution bandwidth 100 MHz). For better comparison, all spectra are normalized to the out-of-band amplified spontaneous emission (ASE) noise level. We indicate the frequencies \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$f_{1}, \;f_{2}, \;f_{3}, f_{4}$$\end{document} f 1 , f 2 , f 3 , f 4 of the Tx comb, for which a constant free spectral range (FSR) is maintained throughout the experiment. b Constellation signal-to-noise ratio (CSNR) as a function of the symbol rate for 16QAM (blue dots and solid blue line) and 32QAM signals (red dots and red dashed line)—measured in an optical back-to-back (ob2b) configuration and after transmission over 87 km of single-mode fiber (blue and red cross, see inset). The results are compared to other high-symbol-rate optical signaling experiments that rely on single digital-to-analog converters (DACs) , , , or photonic-electronic , , (circular markers) or purely electronic – , – (square markers) multiplexing techniques. References , , demonstrate pulse-amplitude modulation (PAM) signaling, whereas the other publications show QAM signals. References – and – use the commercially available signal generators Keysight M8199A and M8199B, respectively, which rely two time-interleaved DAC channels. Insets: Exemplary constellation diagrams for 16QAM and 32QAM 320 GBd signals and measured bit-error ratio (BER) obtained for the optical back-to-back configuration
Article Snippet: References – and – use the commercially available signal generators Keysight M8199A and M8199B, respectively, which rely two time-interleaved DAC channels.
Techniques: Generated, Comparison, Amplification, Transmission Assay, Multiplexing
![a Optical spectra of 16QAM signals with symbol rates ranging from 80 GBd to 320 GBd generated using spectrally sliced OAWG and measured using a high-resolution optical spectrum analyzer (AP2060, Apex Technologies, Marcoussis, France, resolution bandwidth 100 MHz). For better comparison, all spectra are normalized to the out-of-band amplified spontaneous emission (ASE) noise level. We indicate the frequencies \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$f_{1}, \;f_{2}, \;f_{3}, f_{4}$$\end{document} f 1 , f 2 , f 3 , f 4 of the Tx comb, for which a constant free spectral range (FSR) is maintained throughout the experiment. b Constellation signal-to-noise ratio (CSNR) as a function of the symbol rate for 16QAM (blue dots and solid blue line) and 32QAM signals (red dots and red dashed line)—measured in an optical back-to-back (ob2b) configuration and after transmission over 87 km of single-mode fiber (blue and red cross, see inset). The results are compared to other high-symbol-rate optical signaling experiments that rely on single digital-to-analog converters (DACs) , , , or photonic-electronic , , (circular markers) or purely electronic – , – (square markers) multiplexing techniques. References , , demonstrate pulse-amplitude modulation (PAM) signaling, whereas the other publications show QAM signals. References – and – use the commercially available signal generators Keysight <t>M8199A</t> and M8199B, respectively, which rely two time-interleaved DAC channels. Insets: Exemplary constellation diagrams for 16QAM and 32QAM 320 GBd signals and measured bit-error ratio (BER) obtained for the optical back-to-back configuration](https://pub-med-central-images-cdn.bioz.com/pub_med_central_ids_ending_with_9824/pmc12479824/pmc12479824__41377_2025_1937_Fig5_HTML.jpg)