Visible-light communication (VLC) stands as a promising component of the future communication network by providing high-capacity, low-latency, and high-security wireless communication. Superluminescent diode (SLD) is proposed as a new light emitter in the VLC system due to its properties of droop-free emission, high optical power density, and low speckle-noise. In this paper, we analyze a VLC system based on SLD, demonstrating effective implementation of carrierless amplitude and phase modulation (CAP). We create a low-complexity memory-polynomial-aided neural network (MPANN) to replace the traditional finite impulse response (FIR) post-equalization filters of CAP, leading to significant mitigation of the linear and nonlinear distortion of the VLC channel. The MPANN shows a gain in Q factor of up to 2.7 dB higher than other equalizers, and more than four times lower complexity than a standard deep neural network (DNN), hence, the proposed MPANN opens a pathway for the next generation of robust and efficient neural network equalizers in VLC. We experimentally demonstrate a proof-of-concept 2.95-Gbit/s transmission using MPANN-aided CAP with 16-quadrature amplitude modulation (16-QAM) through a 30-cm channel based on the 442-nm blue SLD emitter.
Demonstration of a low-complexity memory-polynomial-aided neural network equalizer for CAP visible-light communication with superluminescent diode
First published at:Aug 21, 2020
1. Tanaka Y, Haruyama S, Nakagawa M. Wireless optical transmissions with white colored LED for wireless home links. In 11th IEEE International Symposium on Personal Indoor and Mobile Radio Communications 1325–1329 (IEEE, 2000); http://doi.org/10.1109/PIMRC.2000.881634.
2. Chi N, Haas H, Kavehrad M, Little T D C, Huang X L. Visible light communications: demand factors, benefits and opportunities [Guest Editorial]. IEEE Wirel Commun 22, 5–7 (2015).
3. Haas H. LiFi is a paradigm-shifting 5G technology. Rev Phys 3, 26–31 (2018).
4. Russell C L. 5 G wireless telecommunications expansion: Public health and environmental implications. Environ Res 165, 484–495 (2018).
5. Zhang Y L, Wang L, Wang K, Wong K S, Wu K S. Recent advances in the hardware of visible light communication. IEEE Access 7, 91093–91104 (2019).
6. Stepniak G, Kowalczyk M, Maksymiuk L, Siuzdak J. Transmission beyond 100 Mbit/s using LED both as a transmitter and receiver. IEEE Photon Technol Lett 27, 2067–2070 (2015).
7. Ho K T, Chen R, Liu G Y, Shen C, Holguin-Lerma J et al. 3.2 Gigabit-per-second visible light communication link with InGaN/GaN MQW micro-photodetector. Opt Express 26, 3037–3045 (2018).
8. Kang C H, Liu G Y, Lee C, Alkhazragi O, Wagstaff J M et al. Semipolar (2021) InGaN/GaN micro-photodetector for gigabit-per-second visible light communication. Appl Phys Express 13, 014001 (2020).
9. Cheng C H, Shen C C, Kao H Y, Hsieh D H, Wang H Y et al. 850/940-nm VCSEL for optical communication and 3D sensing. Opto-Electron Adv 1, 180005 (2018).
10. Tsonev D, Chun H, Rajbhandari S, McKendry J J D, Videv S et al. A 3-Gb/s single-LED OFDM-based wireless VLC link using a gallium nitride μ LED. IEEE Photon Technol Lett 26, 637–640 (2014).
11. Janjua B, Oubei H M, Durán Retamal J R, Ng T K, Tsai C T et al. Going beyond 4 Gbps data rate by employing RGB laser diodes for visible light communication. Opt Express 23, 18746–18753 (2015).
12. Bian R, Tavakkolnia I, Haas H. 15.73 Gb/s visible light communication with off-the-shelf LEDs. J Light Technol 37, 2418–2424 (2019).
13. Shi J Y, Zhu X, Wang F M, Zou P, Zhou Y J et al. Net data rate of 14.6 Gbit/s underwater VLC utilizing silicon substrate common-anode five primary colors LED. In Optical Fiber Communication Conference (OFC) M3I.5 (OSA, 2019);http://doi.org/10.1364/OFC.2019.M3I.5.
14. Wei L Y, Chow C W, Liu Y, Yeh C H. Multi-Gbit/s phosphor-based white-light and blue-filter-free visible light communication and lighting system with practical transmission distance. Opt Express 28, 7375–7381 (2020).
15. Feltin E, Castiglia A, Cosendey G, Sulmoni L, Carlin J F et al. Broadband blue superluminescent light-emitting diodes based on GaN. Appl Phys Lett 95, 081107 (2009).
16. Kafar A, Stańczyk S, Wi?niewski P, Oto T, Makarowa I et al. Design and optimization of InGaN superluminescent diodes. Phys Status Solidi 212, 997–1004 (2015).
17. Shen C, Ng T K, Leonard J T, Pourhashemi A, Nakamura S et al. High-brightness semipolar (2021) blue InGaN/GaN superluminescent diodes for droop-free solid-state lighting and visible-light communications. Opt Lett 41, 2608–2611 (2016).
18. Cahill R, Maaskant P P, Akhter M, Corbett B. High power surface emitting InGaN superluminescent light-emitting diodes. Appl Phys Lett 115, 171102 (2019).
19. Rashidi A, Rishinaramangalam A K, Aragon A A, Mishkat-Ul-Masabih S, Monavarian M et al. High-speed nonpolar InGaN/GaN superluminescent diode with 2.5 GHz modulation bandwidth. IEEE Photon Technol Lett 32, 383–386 (2020).
20. Andreeva E V, Anikeev, A S, Il'chenko, S N, Chamorovskiy, A, Shidlovski, V R et al. Highly efficient superluminescent diodes and SLD-based combined light sources of red spectral range for applications in biomedical imaging. In Proceedings of the SPIE 10483, Optical Coherence Tomography and Coherence Domain Optical Methods in Biomedicine XXII, 104832T (SPIE, 2018); http://doi.org/10.1117/12. 2288246.
21. Goldberg G R, Boldin A, Andersson S M L, Ivanov P, Ozaki N et al. Gallium nitride superluminescent light emitting diodes for optical coherence tomography applications. IEEE J Sel Top Quantum Electron 23, 2000511 (2017).
22. Primerov N, Dahdah J, Gloor S, von Niederh?usern T, Matuschek N et al. A compact red-green-blue superluminescent diode module: A novel light source for AR microdisplays. in Proceedings of the SPIE Digital Optical Technologies 2019 110620F (SPIE, 2019); http://doi.org/10.1117/12.2527626.
23. Alatawi A A, Holguin-Lerma J A, Kang C H, Shen C, Subedi R C et al. High-power blue superluminescent diode for high CRI lighting and high-speed visible light communication. Opt Express 26, 26355–26364 (2018).
24. Shen C, Lee C, Ng T K, Nakamura S, Speck J S et al. High-speed 405-nm superluminescent diode (SLD) with 807-MHz modulation bandwidth. Opt Express 24, 20281–20286 (2016).
25. Shen C, Holguin-Lerma J A, Alatawi A A, Zou P, Chi N et al. Group-III-nitride superluminescent diodes for solid-state lighting and high-speed visible light communications. IEEE J Sel Top Quantum Electron 25, 2000110 (2019).
26. Hu F C, Holguin-Lerma J A, Mao Y, Shen C, Sun X B et al. 3.8-Gbit/s visible light communication (VLC) based on 443-nm superluminescent diode and bit-loading discrete-multiple-tone (DMT) modulation scheme. In Proceedings of the SPIE 11307, Broadband Access Communication Technologies XIV 113070H (SPIE, 2020); http://doi.org/10.1117/12.2543983.
27. Chi N, Shi M. Advanced modulation formats for underwater visible light communications [Invited]. Chin Opt Lett 16, 120603 (2018).
28. Wu F M, Lin C T, Wei C C, Chen C W, Chen Z Y et al. Performance comparison of OFDM signal and CAP signal over high capacity RGB-LED-based WDM visible light communication. IEEE Photonics J 5, 7901507 (2013).
29. Li G Q, Hu F C, Zhao Y H, Chi N. Enhanced performance of a phosphorescent white LED CAP 64QAM VLC system utilizing deep neural network (DNN) post equalization. In 2019 IEEE/CIC International Conference on Communications in China (ICCC) 173–176 (IEEE, 2019);http://doi.org/10.1109/ICCChina.2019.8855926.
30. Rodes R, Wieckowski M, Pham T T, Jensen J B, Turkiewicz J et al. Carrierless amplitude phase modulation of VCSEL with 4 bit/s/Hz spectral efficiency for use in WDM-PON. Opt Express 19, 26551–26556 (2011).
31. Osahon I N, Rajbhandari S, Popoola W O. Performance comparison of equalization techniques for SI-POF multi-Gigabit communication with PAM- M and device non-linearities. J Light Technol 36, 2301–2308 (2018).
32. Feng J L, Lu S N. Performance analysis of various activation functions in artificial neural networks. J Phys: Conf Ser 1237, 022030 (2019).
33. Zhang J. Memory-polynomial digital pre-distortion for linearity improvement of directly-modulated multi-IF-over-Fiber LTE mobile fronthaul. In Optical Fiber Communications Conference (OFC), Tu2B.3 (OSA, 2016).
34. Morgan D R, Ma Z, Kim J, Zierdt M G, Pastalan J. A generalized memory polynomial model for digital predistortion of RF power amplifiers. IEEE Trans Signal Process 54, 3852–3860 (2006).
35. Ramachandran P, Zoph B, Le Q V. Searching for activation functions. arXiv: 1710.05941 (2017).
36. Shu L, Li J Q, Wan Z Q, Zhang W J, Fu S N et al. Overestimation trap of artificial neural network: Learning the rule of PRBS. In 2018 European Conference on Optical Communication (ECOC) 1–3 (IEEE, 2018);http://doi.org/10.1109/ECOC.2018.8535327.
37. Lu X Y, Lu C, Yu W X, Qiao L, Liang S Y et al. Memory-controlled deep LSTM neural network post-equalizer used in high-speed PAM VLC system. Opt Express 27, 7822–7833 (2019).
38. Li M, Zhang T, Chen Y Q, Smola A J. Efficient mini-batch training for stochastic optimization. In Proceedings of the 20th ACM SIGKDD International Conference on Knowledge Discovery and Data Mining 661–670 (ACM Press, 2014);http://doi.org/10.1145/2623330.2623612.
39. Chi N, Zhou Y J, Liang S Y, Wang F M, Li J H et al. Enabling technologies for high-Speed visible Light communication employing CAP modulation. J Light Technol 36, 510–518 (2018).
40. Wang Y G, Tao L, Huang X X, Shi J Y, Chi N. 8-Gb/s RGBY LED-based WDM VLC system employing high-order CAP modulation and hybrid post equalizer. IEEE Photon J 7, 7904507 (2015).
41. Haigh P A, Chvojka P, Zvánovec S, Ghassemlooy Z, Darwazeh I. Analysis of Nyquist pulse shapes for carrierless amplitude and phase modulation in visible light communications. J Light Technol 36, 5023–5029 (2018).
42. Shi J Y, Zhou Y J, Zhang J W, Chi N, Yu J J. Enhanced performance utilizing joint processing algorithm for CAP signals. J Light Technol 36, 3169–3175 (2018).
43. Chi N, Zhao Y H, Shi M, Zou P, Lu X Y. Gaussian kernel-aided deep neural network equalizer utilized in underwater PAM8 visible light communication system. Opt Express 26, 26700–26712 (2018).
44. Mathews V J. Adaptive polynomial filters. IEEE Signal Process Mag 8, 10–26 (1991).
45. Fehenberger T, Hanik N. Mutual information as a figure of merit for optical fiber systems. arXiv:1405.2029 (2014).
the National Key Research, Development Program of China (2017YFB0403603); the NSFC project (No. 61925104); the financial support from King Abdullah University of Science and Technology (KAUST) through BAS/1/1614-01-01, REP/1/2878-01-01, GEN/1/6607-01-01, and KCR/1/2081-01-01
Get Citation: Hu F C, Holguin-Lerma J A, Mao Y, Zou P, Shen C et al. Demonstration of a low-complexity memory-polynomial-aided neural network equalizer for CAP visible-light communication with superluminescent diode. Opto-Electron Adv 3, 200009 (2020).