Remote Photonic THz Generation Using an Optical Frequency Comb and Multicore Fiber

[EN] This paper proposes and demonstrates a photonic THz generation technique based on an optical frequency comb and multicore fiber (MCF) transmission, with the advantage of remote generation with great reconfigurability and reduced digital signal processing (DSP). The feasibility of the proposed technique is evaluated experimentally comparing the performance when transmitting a data wavelength and a local oscillator for optical heterodyning over a single core or over different cores in a 1-km MCF link. The proposed remote photonic THz generation technique is demonstrated employing a 16QAM 12.5 GBd signal. A short wireless transmission at 183 GHz center frequency with 0.25 m antenna-separation is achieved after 1 km MCF, meeting the soft-decision decision forward error correction (SD-FEC) bit error rate (BER) recommendation of 2 center dot 10(-2). The analysis includes the received photocurrent range for which the BER meets the standard hard-decision forward error correction (HD-FEC) recommendation of 3.8 center dot 10(-3) BER. The BER performance is analyzed considering different DSP configurations, with and without frequency offset estimation (FOE) and decision-driven least mean squares (DD LMS) equalization. The performance of the remote photonic THz generation technique is evaluated comparatively against traditional free-running laser transmission over MCF, confirming the advantage of using comb generation to reduce the frequency offset fluctuation and simplify the DSP.This work was supported by Spanish State Research Agency under Grants PID2019-106163RJ-I00/AEI/10.13039/501100011033 MULTICORE+ and MINECO/FEDER UE RTI2018-101296-B-I00 MULTI-BEAM5G projects, in part by the European Union'sHorizon 2020 Research and Innovation Programme underGrant H2020-EU.2.1.1.-762119 ULTRAWAVE, and in part by the Engineering and Physical Sciences Research Council under Grant EPSRC EP/P003990/1 COALESCE. The work of Maria Morant supported by Generalitat Valenciana under Grant BEST/2019/047.Morant, M.; González-Guerrero, L.; Renaud, CC.; Llorente, R. (2021). Remote Photonic THz Generation Using an Optical Frequency Comb and Multicore Fiber. Journal of Lightwave Technology. 39(24):7621-7627. https://doi.org/10.1109/JLT.2021.311508476217627392

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