GENERATION OF COHERENT OPTICAL RADIATION MODULATED BY A QUADRATURE PHASE-SHIFT KEYED RADIO SIGNAL
Abstract
The use of broadband optical amplification, wave division multiplexing, dispersion compensation of optical radiation, and differential phase-shift keying enables data transmission at rates of up to 40 Gbit/s. Prospects for further increasing transmission rates to 100 Gbit/s are associated with the use of multilevel modulation formats for radio signals on multiple subcarrier frequencies, modulation of the radiation from a single optical quantum generator by radio signals on multiple subcarriers, balanced homodyne detection of coherent optical radiation, and digital signal processing. Symbol-based transmission via quadrature phase-shift keying (QPSK) provides high data rates. Prior studies have substantiated the use of a single-sideband coherent optical radiation generation algorithm with subcarrier QPSK modulation. Due to hardware instabilities, amplitude and phase errors may arise, leading to quadrature imbalance. These inaccuracies introduce additional errors during demodulation of the received signal, which can significantly degrade reception interference immunity. The aim of this study is to analyze the process of generating single-sideband optical radiation modulated by a QPSK radio signal on a subcarrier frequency using two parallel Mach–Zehnder interferometers. A distinguishing feature of the proposed approach is that the derived mathematical relationships make it possible to subsequently assess the impact of amplitude and phase errors in quadrature signal generation (quadrature imbalance) on reception quality.
References
1. Anichkin A.D., Olenev V.L. Primenenie lazernykh sistem svyazi dlya peredachi dannykh v kosmich-eskom prostranstve [Application of laser communication systems for data transmission in outer space], Sistemnyy analiz i logistika [System Analysis and Logistics], 2024, No. 3 (41), pp. 17-24. DOI: 10.31799/2077 5687-2024-3-17-24.
2. Ibragimov R.Z., Fokin V.G. Proektirovanie sovremennykh opticheskikh transportnykh setey svyazi [De-sign of modern optical transport communication networks]. Saint Petersburg: Lan', 2023, 112 p. ISBN 978-5-507-45199-9.
3. Blaunshteyn N.Sh., Kruk E.A., Sergeev M.B. Opticheskaya svyaz': optovolokonnaya, atmosfernaya: monografiya [Optical communication: fiber-optic and free-space systems: monograph]. Saint Petersburg: GUAP, 2016, 286 p. ISBN: 978-5-8088-1157-7.
4. Kim Geuk-Nam, Park Sang-Young, Seong Sehyun, Lee Joohee, Choi Suyong, Kim Young-Eon, Ryu Han-Gyeol, Lee Sungmoon, Choi Jae-Young, Han Sang Kook. The VISION – Concept of laser cross-link systems using nanosatellites in formation flying, Acta Astronautica, 2023, Vol. 211, pp. 877-897.
5. Mahmood H.A. 40 Gbps Laguerre-Gaussian and Hermite-Gaussian Optical Mode Division Multiplex-ing for Radio over Fiber System, Journal of Optical Communications, 2021, Vol. 42, No. 4, pp. 689-692. DOI 10.1515/joc-2018-0161.
6. Hui R., Zhu B., Huang R., Allen C., Demarest K. and Richards D. Subcarrier multiplexing for high-speed optical transmission, IEEE Journal of Lightwave Technology, March, 2002, Vol. 20, No. 3, pp. 417-427.
7. Hui R., Zhu B., Huang R., Allen C., Demarest K., and Richards D. 10-Gb/s SCM fiber system using optical SSB modulation, IEEE Photonics Technology Letters, August, 2001, Vol. 13, No. 8, pp. 896-898.
8. Mahmood H.A., Ahmed R.K. Radio over fiber performance evaluation in optical communication system utilizing FBG under different DCF schemes for DPSK format, Journal of Engineering and Applied Sci-ences, 2019, Vol. 14, No. 4, pp. 1130-1137. DOI 10.36478/jeasci.2019.1130.1137.
9. Ahmed R.K., Mahmood H.A. Performance analysis of PAM intensity modulation based on dispersion compensation fiber technique for optical transmission system, 2018 1st International Scientific Confer-ence of Engineering Sciences-3rd Scientific Conference of Engineering Science (ISCES), 2018,
pp. 126-130. DOI: 10.1109/ISCES.2018.8340540.
10. Mahmood H.A., Rumyantsev R.K., Al-Karawi H.S. Evolution of radio over free space optical commu-nication utilizing subcarrier multiplexing / amplitude shift keying, Izvestiya YuFU. Tekhnicheskie nauki [Izvestiya SFedU. Engineering Sciences], 2020, No. 5 (215), pp. 141-149. DOI: 10.18522/2311-3103-2020-5-141-149.
11. Makhmud Kh.A.M., Rumyantsev K.E. Formirovanie odnopolosnoy kvadraturnoy fazovoy manipulyatsii radiosignalov na podnesushchikh chastotakh v kogerentnoy opticheskoy sisteme kommunikatsii [Gener-ation of single-sideband quadrature phase-shift keyed radio signals on subcarrier frequencies in a coher-ent optical communication system], Izvestiya YuFU. Tekhnicheskie nauki [Izvestiya SFedU. Engineering Sciences], 2022, No. 5 (229), pp. 209-220. DOI 10.18522/2311-3103-2022-5-209-220. – Rezhim dostupa: https://izv-tn.tti.sfedu.ru/index.php/izv_tn/article/view/838/1024.
12. Makhmud Kh.A.M., Rumyantsev K.E., Al'-Begat A.Kh.Sh. Analiz voskhodyashchego lazernogo kanala sputnikovoy kommunikatsii v usloviyakh atmosfernoy turbulentnosti [Analysis of the Uplink Laser Channel in Satellite Communication under Atmospheric Turbulence Conditions], Izvestiya YuFU. Tekhnicheskie nauki [Izvestiya SFedU. Engineering Sciences], 2023, No. 4 (234), pp. 174-191. DOI 10.18522/2311-3103-2023-4-174-191.
13. Mahmood H.A., Rumyantsev K.Y. Effect of FBG Compensated Dispersion on SCM/ASK Radio over Fiber System, 12th International Congress on Image and Signal Processing, BioMedical Engineering and Informatics (CISP-BMEI), 2019, Art. No 8966032, pp. 1-5. DOI 10.1109/CISP-BMEI48845.2019.8966032.
14. Kulikov G.V., Lelyukh A.A. Vliyanie amplitudnogo i fazovogo razbalansa kvadratur na pomekhostoychivost' kogerentnogo priema signalov s kvadraturnoy amplitudnoy modulyatsiey [Impact of amplitude and phase quadrature imbalance on the noise immunity of coherent reception of quadrature amplitude modulated signals], Rossiyskiy tekhnologicheskiy zhurnal [Russian Technological Journal], 2021, 9 (1), pp. 29-37. Available at: https://doi.org/10.32362/2500-316X-2021-9-1-29-37.
15. Kulikov G.V., Nesterov A.V., Lelyukh A.A. Pomekhoustoychivost' priema signalov s kvadraturnoy ampli-tudnoy manipulyatsiey v prisutstvii garmonicheskoy po mekhi [Noise Immunity of Quadrature Ampli-tude Modulated Signal Reception in the Presence of Harmonic Interference], Zhurnal radioelektroniki (elektronnyy zhurnal) [Journal of Radio Electronics (electronic journal)], 2018, 11.
16. Sklyar Bernard. TSifrovaya svyaz'. Teoreticheskie osnovy i prakticheskoe primenenie. Digital Commu-nications: Fundamentals and Applications [Digital communications: fundamentals and applications]. 2nd ed. Moscow: Vil'yams, 2007, 1104 p. ISBN 0-13-084788-7.
17. Berlin A.N. Kommutatsiya v sistemakh i setyakh svyazi [Switching in communication systems and net-works]. Moscow: Eko-Trendz, 2006, 344 p. ISBN 5-88405-073-9.
18. Prokis, Dzh. Tsifrovaya svyaz'. Digital Communications [Digital communications], ed.by
D.D. Kievskogo. Moscow: Radio i svyaz', 2000, 800 p. ISBN 5-256-01434-X.
19. Vargauzin V.A., Tsikin I.A. Metody povysheniya energeticheskoy i spektral'noy effektivnosti tsifrovoy radiosvyazi [Methods for enhancing the energy and spectral efficiency of digital radio communication]. Saint-Petersburg: BKhV-Peterburg, 2013.
20. Drevko D.R., Zyuryukin Yu.A., Ushakov N.M. Modifikatsii elektroopticheskogo modulyatora Makha–Tsendera dlya upravleniya lazernym izlucheniem povyshennoy moshchnosti [Modifications of the mach–zehnder electro-optic modulator for high-power laser radiation control], Nanoelektronika, nanofotonika i nelineynaya fizika: Mater. V konf. molodykh uchenykh [Nanoelectronics, Nanophotonics and Nonlinear Physics: V Rising Scholars Conference Materials]. Saratov, 2010, pp. 18-19.
21. Slepov N.N. Opticheskie volokonnye konvertory i modulyatory [Optical fiber converters and modula-tors], Elektronika: nauka, tekhnologiya, biznes [Electronics: Science, Technology, Business], 2000, No. 6, pp. 6-10.
22. Voblikov E.D., Volyntsev A.B., Zhuravlev A.A., Kichanov A.V., Ponomarev R.S., Shevtsov D.I. Inte-gral'no-opticheskiy modulyator na osnove interferometra Makha–Tsendera s asimmetrichnoy topologiey volnovodov [Integrated optical modulator based on a Mach–Zehnder interferometer with asymmetric waveguide topology], Tr. MAI [Trudy MAI], 2011, No. 46.
23. Seimetz M. High-order modulation for optical fiber transmission. Springer Science & Business Media, 2009, 252 p.
