Design of LCoS-Based Twin 1×40 Wavelength Selective Switch

doi:10.12142/ZTECOM.202404004

ZTE Communications ›› 2024, Vol. 22 ›› Issue (4): 18-28.DOI: 10.12142/ZTECOM.202404004

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Design of LCoS-Based Twin 1×40 Wavelength Selective Switch

WANG Han¹^,², LIU Maoqi¹^,², FENG Zhenhua³^,⁴, LIU Minghuan³^,⁴, MAO Baiwei³^,⁴()

^1.School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan 430074, China
^2.Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China
^3.WDM System Department of Wireline Product R&D Institute, ZTE Corporation, Wuhan 430223, China
^4.State Key Laboratory of Mobile Network and Mobile Multimedia Technology, Shenzhen 518055, China

Received:2024-06-24 Online:2024-12-20 Published:2024-12-03
About author:WANG Han received her BS degree from Beijing Jiaotong University, China and is pursuing a master's degree at Huazhong University of Science and Technology, China. Her research interests include the optical design of wavelength selective switches and LCoS algorithms, with a current focus on designing multi-band integrated WSS and M×N WSS.
LIU Maoqi received his bachelor's degree from the School of Optical and Electronic Information, Huazhong University of Science and Technology, China. Currently, he is a joint PhD student at the National Engineering Laboratory for Next Generation Internet Access System, Huazhong University of Science and Technology, and the Photonics Research Institute, Hong Kong Polytechnic University, China. His research primarily focuses on multi-band WSS, aiming to improve their efficiency and scalability in modern optical networks. Additionally, he explores the integration of optical fiber communication and sensing, seeking innovative solutions to combining these technologies for multifunctional applications in 6G telecommunications.
FENG Zhenhua received his PhD from Huazhong University of Science and Technology, China in 2017. He has been engaged in the research and development of optical fiber communication systems and algorithms for about five years with more than 70 journal and conference publications and about 10 granted patents. His research interests mainly lie in the design and verification of optical transmission systems and DSP algorithms.
LIU Minghuan received his PhD from Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences. He has worked in the Wavelength Division System Department of the Cable Research Institute, ZTE Corporation since June 2023, engaged in the work related to WSS design.
MAO Baiwei (mao.baiwei@zte.com.cn) received his PhD from Nankai University, China in 2022. He has worked in the Wavelength Division System Department of the Cable Research Institute, ZTE Corporation since July 2022, engaged in optical transmission system planning and optimization.
Supported by:
ZTE Industry?University?Institute Cooperation Funds(IA20230614004)

Abstract

Abstract:

Wavelength selective switch (WSS) is the crucial component in the reconfigurable optical add/drop multiplexer (ROADM), which plays a pivotal role in the next-generation all-optical networks. We present a compact architecture of twin 1×40 liquid crystal on silicon (LCoS)-based WSS, which can be regarded as a 4f system in the wavelength direction and a 2f system in the switching direction. It is designed with theoretical analysis and simulation investigation. Polarization multiplexing is employed for two sources of twin WSS by polarization conversion before the common optical path. The WSS system attains a coupling efficacy exceeding 96% for 90% of the ports through simulation optimization. The 3 dB bandwidth can be achieved by more than 44 GHz at a 50 GHz grid for all 120 channels at all deflection ports. This work establishes a solid foundation for developing high-performance WSS with larger port counts.

Key words: wavelength selective switch (WSS), liquid crystal on silicon (LCoS), optical structure design, insertion loss

WANG Han, LIU Maoqi, FENG Zhenhua, LIU Minghuan, MAO Baiwei. Design of LCoS-Based Twin 1×40 Wavelength Selective Switch[J]. ZTE Communications, 2024, 22(4): 18-28.

Figures/Tables 13

References 20

1	KOZDROWSKI S, ŻOTKIEWICZ M, SUJECKI S. Optimization of optical networks based on CDC-ROADM technology [J]. Applied sciences, 2019, 9(3): 399. DOI: 10.3390/app9030399
2	FORD J E, AKSYUK V A, BISHOP D J, et al. Wavelength add-drop switching using tilting micromirrors [J]. Journal of lightwave technology, 1999, 17(5): 904–911. DOI: 10.1109/50.762910
3	DOERR C R, STULZ L W, LEVY D S, et al. Silica-waveguide 1×9 wavelength- selective cross connect [C]//Optical Fiber Communication Conference. OSA, 2002. DOI:10.1109/OFC.2002.1036752
4	BAXTER G, FRISKEN S, ABAKOUMOV D, et al. Highly programmable wavelength selective switch based on liquid crystal on silicon switching elements [C]//Proc. Optical Fiber Communication Conference and the National Fiber Optic Engineers Conference. IEEE, 2006. DOI:10.1109/OFC.2006.215365
5	MA Y R, STEWART L, ARMSTRONG J, et al. Recent progress of wavelength selective switch [J]. Journal of lightwave technology, 2021, 39(4): 896–903. DOI: 10.1109/JLT.2020.3022375
6	HAN T, PLUMRIDGE J, FRISKEN S, et al. LCoS-based matrix switching for 2 × 4 WSS for fully flexible channel selection [C]//Proc. International Conference on Photonics in Switching (PS). IEEE, 2012: 1–3
7	YANG H N, ROBERTSON B, CHU D P. Crosstalk reduction in holographic wavelength selective switches based on phase-only LCoS devices [C]//Proc. Optical Fiber Communication Conference. OSA, 2014. DOI: 10.1364/ofc.2014.th2a.23
8	YANG H N, ROBERTSON B, WILKINSON P, et al. Small phase pattern 2D beam steering and a single LCOS design of 40 1 × 12 stacked wavelength selective switches [J]. Optics express, 2016, 24(11): 12240–12253. DOI: 10.1364/OE.24.012240
9	HE J, NORWOOD R A, BRANDT-PEARCE M, et al. A survey on recent advances in optical communications [J]. Computers & electrical engineering, 2014, 40(1): 216–240. DOI: 10.1016/j.compeleceng.2013.11.017
10	ROBERTSON B, YANG H N, REDMOND M M, et al. Demonstration of multi-casting in a 1 × 9 LCoS wavelength selective switch [J]. Journal of lightwave technology, 2014, 32(3): 402–410. DOI: 10.1109/JLT.2013.2293919
11	WANG M, ZONG L J, MAO L, et al. LCoS SLM study and its application in wavelength selective switch [J]. Photonics, 2017, 4(2): 22. DOI: 10.3390/photonics4020022
12	MILEWSKI G, ENGSTRÖM D, BENGTSSON J. Diffractive optical elements designed for highly precise far-field generation in the presence of artifacts typical for pixelated spatial light modulators [J]. Applied optics, 2007, 46(1): 95–105. DOI: 10.1364/AO.46.000095
13	PERSSON M, ENGSTRÖM D, BENGTSSON J, et al. Realistic treatment of spatial light modulator pixelation in real-time design algorithms for holographic spot generation [C]//Proc. Digital Holography and Three-Dimensional Imaging. OSA, 2011. DOI: 10.1364/dh.2011.dwc32
14	PERSSON M, ENGSTRÖM D, GOKSÖR M. Reducing the effect of pixel crosstalk in phase only spatial light modulators [J]. Optics express, 2012, 20(20): 22334–22343. DOI: 10.1364/OE.20.022334
15	NIE J W, DONG L Y, TONG X W, et al. Phase flicker minimisation for crosstalk suppression in optical switches based on digital liquid crystal on silicon devices [J]. Optics express, 2021, 29(7): 10556–10567. DOI: 10.1364/OE.415800
16	ROBERTSON B, ZHANG Z C, YANG H N, et al. Reduction of crosstalk in a colourless multicasting LCOS-based wavelength selective switch by the application of wavefront encoding [C]//Proc. Next-Generation Optical Communication: Components, Sub-Systems, and Systems. SPIE, 2012. DOI: 10.1117/12.907281
17	HUANG L H, RAO C H. Wavefront sensorless adaptive optics: a general model-based approach [J]. Optics express, 2011, 19(1): 371–379. DOI: 10.1364/OE.19.000371
18	FRISKEN S J. Polarization diverse wavelength selective switch: US20170214482 [P]. 2017
19	ZHOU Y R, KEENS J, WAKIM W. High capacity innovations enabling scalable optical transmission networks [J]. Journal of lightwave technology, 2023, 41(3): 957–967. DOI: 10.1109/JLT.2022.3206277
20	MAROM D M, NEILSON D T, GREYWALL D S, et al. Wavelength-selective 1×K switches using free-space optics and MEMS micromirrors: theory, design, and implementation [J]. Journal of lightwave technology, 2005, 23(4): 1620–1630. DOI: 10.1109/JLT.2005.844213

Component	Transmission	Pass	Loss/dB
Grism	0.87	2	-1.21
Intrinsic LCoS reflectivity	0.87	1	-0.60
System absorption	0.85	2	-1.42
Fiber coupling	0.85	1	-0.71
Total			-3.94

Component	Transmission	Pass	Loss/dB
Grism	0.87	2	-1.21
Intrinsic LCoS reflectivity	0.87	1	-0.60
System absorption	0.85	2	-1.42
Fiber coupling	0.85	1	-0.71
Total			-3.94

T_i	Variables	Operand
T₁	Coupling efficiency	POPD(0)
T₂	Beam width on LCoS	POPD(23)
T₃	Beam size of the waist near LCoS plane	POPD(7)
T₄	Overlap of beams of different polarization on LCoS	DIFF
T₅	Width of beam coverage in x-direction of LCoS	REAX
T₆	Coordinate values of different ports returning to FA	REAX
T₇	Beam size of different ports returning to FA	POPD(23)

T_i	Variables	Operand
T₁	Coupling efficiency	POPD(0)
T₂	Beam width on LCoS	POPD(23)
T₃	Beam size of the waist near LCoS plane	POPD(7)
T₄	Overlap of beams of different polarization on LCoS	DIFF
T₅	Width of beam coverage in x-direction of LCoS	REAX
T₆	Coordinate values of different ports returning to FA	REAX
T₇	Beam size of different ports returning to FA	POPD(23)

Port	1 524 nm	1 550 nm	1 572 nm	Port	1 524 nm	1 550 nm	1 572 nm
1	87.00%	81.61%	60.24%	21	93.03%	96.72%	94.15%
2	91.16%	89.09%	77.83%	22	93.12%	96.65%	93.91%
3	89.42%	84.24%	87.70%	23	93.01%	96.52%	94.09%
4	91.57%	96.24%	86.84%	24	92.98%	96.65%	93.75%
5	91.80%	96.28%	90.88%	25	92.85%	96.63%	93.80%
6	92.02%	96.32%	90.82%	26	93.03%	96.65%	93.78%
7	92.07%	96.39%	91.14%	27	93.04%	96.64%	93.48%
8	92.53%	96.49%	91.60%	28	92.83%	96.65%	93.50%
9	92.36%	96.47%	92.57%	29	92.94%	96.63%	93.38%
10	92.81%	96.56%	92.54%	30	92.81%	96.60%	93.00%
11	92.81%	96.60%	93.00%	31	92.81%	96.56%	92.54%
12	92.94%	96.63%	93.38%	32	92.36%	96.47%	92.57%
13	92.83%	96.65%	93.50%	33	92.53%	96.49%	91.60%
14	93.04%	96.64%	93.48%	34	92.07%	96.39%	91.14%
15	93.03%	96.65%	93.78%	35	92.02%	96.32%	90.82%
16	92.85%	96.63%	93.80%	36	91.80%	96.28%	90.88%
17	92.98%	96.65%	93.75%	37	91.57%	96.24%	86.84%
18	93.01%	96.52%	94.09%	38	89.42%	84.24%	87.70%
19	93.12%	96.65%	93.91%	39	91.16%	89.09%	77.83%
20	93.03%	96.72%	94.15%	40	87.01%	81.61%	60.24%

Design of LCoS-Based Twin 1×40 Wavelength Selective Switch

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