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Ozolins, O., Fan, Y., Udalcovs, A. & Pang, X. (2023). 106.25 Gbaud 4-Level Pulse Amplitude Modulation Links Supporting (2x)100Gigabit Ethernet on Single Lambda. In: 2023 Optical Fiber Communications Conference and Exhibition, OFC 2023 - Proceedings. 2023 Article number Tu3I.1: . Paper presented at 2023 Optical Fiber Communications Conference and Exhibition, OFC 2023 - Proceedings. Institute of Electrical and Electronics Engineers Inc.
Open this publication in new window or tab >>106.25 Gbaud 4-Level Pulse Amplitude Modulation Links Supporting (2x)100Gigabit Ethernet on Single Lambda
2023 (English)In: 2023 Optical Fiber Communications Conference and Exhibition, OFC 2023 - Proceedings. 2023 Article number Tu3I.1, Institute of Electrical and Electronics Engineers Inc. , 2023Conference paper, Published paper (Refereed)
Abstract [en]

We experimentally demonstrate and compare EML- and DML-based optical interconnects with 106.25 Gbaud NRZ-OOK and PAM4 for computing applications. The results show that both transmitters can be used to enable optical-amplification-free transmissions with low-complexity DSP. © 2023 The Author(s).

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers Inc., 2023
Keywords
Light transmission, Pulse amplitude modulation, 4-level, Computing applications, Lambda's, Lower complexity, Optical amplifications, Optical interconnect, Ethernet
National Category
Telecommunications
Identifiers
urn:nbn:se:ri:diva-66077 (URN)10.23919/OFC49934.2023.10117147 (DOI)2-s2.0-85161316411 (Scopus ID)9781957171180 (ISBN)
Conference
2023 Optical Fiber Communications Conference and Exhibition, OFC 2023 - Proceedings
Note

This work was supported by the National Natural Science Foundation of China (U2006217, 61775015), the China Scholarship Council (202107090113), the National Key Research and Development Program of China (2018YFB1801500), the Swedish Research Council (VR) project 2019-05197, the H2020 ICT TWILIGHT Project (No. 781471), the ERDF-funded RINGO project (No. 1.1.1.1/21/A/052), and the RTU Science Support Fund. We thank Keysight Technologies for the loan of the M8199A Arbitrary Waveform Generator and the UXR1104A Infiniium UXR-Series Oscilloscope.

Available from: 2023-08-24 Created: 2023-08-24 Last updated: 2023-08-24Bibliographically approved
Ostrovskis, A., Salgals, T., Krüger, B., Pittalà, F., Joharifar, M., Schatz, R., . . . Ozolins, O. (2023). 106.25 Gbaud On-Off Keying and Pulse Amplitude Modulation Links Supporting Next Generation Ethernet on Single Lambda. Journal of Lightwave Technology
Open this publication in new window or tab >>106.25 Gbaud On-Off Keying and Pulse Amplitude Modulation Links Supporting Next Generation Ethernet on Single Lambda
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2023 (English)In: Journal of Lightwave Technology, ISSN 0733-8724, E-ISSN 1558-2213Article in journal (Refereed) Epub ahead of print
Abstract [en]

Development of Data Center based computing technology require energy efficient high-speed transmission links. This leads to optical amplification-free intensity modulation and direct detection (IM/DD) systems with low complexity equalization compliant with IEEE standardized electrical interfaces. Switching from on-off keying to multi-level pulse amplitude modulation would allow to reduce lane count for next generation Ethernet interfaces. We characterize 106.25 Gbaud on-off keying, 4-level and 6-level pulse amplitude modulation links using two integrated transmitters: O-band directly modulated laser and C-band externally modulated laser. Simple feed forward or decision feedback equalizer is used. We demonstrate 106.25 Gbaud on-off keying links operating without forward error correction for both transmitters. We also show 106.25 Gbaud 4-level and 6-level pulse amplitude modulation links with performance below 6.25% overhead hard-decision forward error threshold of 4.5×10-3. Furthermore, for EML-based transmitter we achieve 106.25 Gbaud 4-level pulse amplitude modulation performance below KP-FEC threshold of 2.2×10-4. That shows that we can use optics to support (2x)100 Gbps Ethernet on single lambda at expense of simple forward error correction.

National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:ri:diva-70085 (URN)10.1109/JLT.2023.3328774 (DOI)
Note

This work was supported by the Swedish Research Council (VR) projects 2019-05197 and BRAIN (2022-04798), The strategic innovation program Smarter Electronic Systems - a joint venture by Vinnova, Formas and the Swedish Energy Agency A-FRONTAHUL project (2023-00659), the H2020 ICT TWILIGHT Project (No. 781471), the ERDF-funded RINGO project (No. 1.1.1.1/21/A/052), the RTU Science Support Fund, the National Natural Science Foundation of China (U2006217, 61775015), the China Scholarship Council (202107090113), and the National Key Research and Development Program of China (2018YFB1801500). (Corresponding authors: X. Pang and O. Ozolins.)

Available from: 2024-01-17 Created: 2024-01-17 Last updated: 2024-01-17Bibliographically approved
Pang, X., Salgals, T., Louchet, H., Che, D., Gruen, M., Matsui, Y., . . . Ozolins, O. (2023). 200 Gb/s Optical-Amplifier-Free IM/DD Transmissions using a Directly Modulated O-band DFB+R Laser targeting LR Applications. Journal of Lightwave Technology, 41(11), 3635
Open this publication in new window or tab >>200 Gb/s Optical-Amplifier-Free IM/DD Transmissions using a Directly Modulated O-band DFB+R Laser targeting LR Applications
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2023 (English)In: Journal of Lightwave Technology, ISSN 0733-8724, E-ISSN 1558-2213, Vol. 41, no 11, p. 3635-Article in journal (Refereed) Published
Abstract [en]

We experimentally demonstrate an O-band single-lane 200 Gb/s intensity modulation direct detection (IM/DD) transmission system using a low-chirp, broadband, and high-power directly modulated laser (DML). The employed laser is an isolator-free packaged module with over 65-GHz modulation bandwidth enabled by a distributed feedback plus passive waveguide reflection (DFB+R) design. We transmit high baud rate signals over 20-km standard single-mode fiber (SSMF) without using any optical amplifiers and demodulate them with reasonably low-complexity digital equalizers. We generate and detect up to 170 Gbaud non-return-to-zero on-off-keying (NRZ-OOK), 112 Gbaud 4-level pulse amplitude modulation (PAM4), and 100 Gbaud PAM6 in the optical back-to-back configuration. After transmission over the 20-km optical-amplifier-free SSMF link, up to 150 Gbaud NRZ-OOK, 106 Gbaud PAM4, and 80 Gbaud PAM6 signals are successfully received and demodulated, achieving bit error rate (BER) performance below the 6.25%-overhead hard-decision (HD) forward-error-correction code (FEC) limit. The demonstrated results show the possibility of meeting the strict requirements towards the development of 200Gb/s/lane IM/DD technologies, targeting 800Gb/s and 1.6Tb/s LR applications.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers Inc., 2023
Keywords
Bandwidth, Direct modulation, distributed-feedback laser, Laser modes, Measurement by laser beam, Modulation, on-off keying, Optical amplifiers, Optical modulation, Optical pulses, pulse amplitude modulation, Amplitude shift keying, Bit error rate, Digital television, Distributed feedback lasers, Error correction, Feedback amplifiers, Laser pulses, Light modulation, Optical communication, Optical signal processing, Single mode fibers, Direct-detection, Directly modulated, Intensity modulations, Non-return-to-zero, On/off-keying, Standard single mode fibers, Transmission systems
National Category
Telecommunications
Identifiers
urn:nbn:se:ri:diva-64741 (URN)10.1109/JLT.2023.3261421 (DOI)2-s2.0-85151524887 (Scopus ID)
Note

This work was supported in part by the H2020 ICT TWILIGHT Project (No. 781471), in part by the Swedish Research Council (VR) projects 2019-05197and BRAIN project No. 2022-04798, in part by RTU Science Support Fund, in part by the ERDF-funded RINGO project (No. 1.1.1.1/21/A/052), and in part by the National Key Research and Development Program of China (2018YFB1801503). (Corresponding authors: X. Pang and O. Ozolins) 

Available from: 2023-05-15 Created: 2023-05-15 Last updated: 2023-12-22Bibliographically approved
Ostrovskis, A., Koenigsmann, M., Salgals, T., Kruger, B., Pittala, F., Scott, R. P., . . . Ozolins, O. (2023). 240/160 Gbaud OOK Silicon Photonics MZM/RRM Transmitters for Short-Reach Applications. In: IEEE International Conference on Group IV Photonics GFP: . Paper presented at IEEE Silicon Photonics Conference, SiPhotonics 2023. Washington, USA. 4 April 2023 through 7 April 2023. IEEE Computer Society
Open this publication in new window or tab >>240/160 Gbaud OOK Silicon Photonics MZM/RRM Transmitters for Short-Reach Applications
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2023 (English)In: IEEE International Conference on Group IV Photonics GFP, IEEE Computer Society , 2023Conference paper, Published paper (Refereed)
Abstract [en]

We demonstrate a record 240 Gbaud on-off keying, 150 Gbaud 4-level pulse amplitude modulation, and 100 Gbaud 6-level pulse amplitude modulation SiP MZM-based transmitter with performance below the 6.25% overhead HD-FEC threshold. We also show a 160 Gbaud on-off keying SiP RRM-based transmitter. 

Place, publisher, year, edition, pages
IEEE Computer Society, 2023
Keywords
Mach-Zehnder modulator, ring resonator modulator, silicon photonics, Digital television, Light modulation, Light modulators, Photonic devices, Transmitters, 4-level, Mach Zehnder modulator, On/off-keying, Performance, Ring resonator, Amplitude shift keying
National Category
Telecommunications
Identifiers
urn:nbn:se:ri:diva-65698 (URN)10.1109/SiPhotonics55903.2023.10141935 (DOI)2-s2.0-85162710120 (Scopus ID)9781665486552 (ISBN)
Conference
IEEE Silicon Photonics Conference, SiPhotonics 2023. Washington, USA. 4 April 2023 through 7 April 2023
Note

Correspondence Address: O. Ozolins (RISE Research Institutes of Sweden); Riga Technical University, Riga, 1048, Latvia; email: oskars.ozolins@ri.se; 

We thank Keysight for hosting the experiment and for loaning the M8199B AWG prototype and the UXR1104A Infiniium UXR-Series Oscilloscope. This work was also supported by the ERDF-funded RINGO project (No. 1.1.1.1/21/A/052), the RTU Science Support Fund, the H2020 ICT TWILIGHT Project (No. 781471), the Swedish Research Council (VR) projects 2019-05197 and 2022-04798, the National Natural Science Foundation of China (U2006217, 61775015), the China Scholarship Council (202107090113), and the National Key Research and Development Program of China (2018YFB1801500).

Available from: 2023-08-11 Created: 2023-08-11 Last updated: 2023-08-11Bibliographically approved
Joharifar, M., Han, M., Schatz, R., Puerta, R., Sun, Y.-T., Fan, Y., . . . Pang, X. (2023). 8.1 Gbps PAM8 Long-Wave IR FSO Transmission using a 9.15-µm Directly-Modulated QCL with an MCT Detector. In: Optical Fiber Communication Conference (OFC) 2023: . Paper presented at Optical Fiber Communication Conference (OFC) 2023.
Open this publication in new window or tab >>8.1 Gbps PAM8 Long-Wave IR FSO Transmission using a 9.15-µm Directly-Modulated QCL with an MCT Detector
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2023 (English)In: Optical Fiber Communication Conference (OFC) 2023, 2023Conference paper, Published paper (Refereed)
Abstract [en]

We experimentally demonstrate a Long-Wave IR FSO link with a 9.15-µm directly modulated quantum cascade laser at room temperature. Up to 8.1 Gb/s PAM8 transmission over 1.4 meter is achieved with a wideband MCT detector.

National Category
Communication Systems
Identifiers
urn:nbn:se:ri:diva-66282 (URN)10.1364/ofc.2023.th1h.1 (DOI)
Conference
Optical Fiber Communication Conference (OFC) 2023
Available from: 2023-09-07 Created: 2023-09-07 Last updated: 2023-12-07Bibliographically approved
Lyu, Z., Zhang, L., Zhang, H., Yang, Z., Yang, H., Zhang, C., . . . Yu, X. (2023). A Beam-Scannable Photonic THz-ISAC System Based on Risley Prisms. In: 2023 Asia Communications and Photonics Conference/2023 International Photonics and Optoelectronics Meetings (ACP/POEM): . Paper presented at 2023 Asia Communications and Photonics Conference/2023 International Photonics and Optoelectronics Meetings (ACP/POEM).
Open this publication in new window or tab >>A Beam-Scannable Photonic THz-ISAC System Based on Risley Prisms
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2023 (English)In: 2023 Asia Communications and Photonics Conference/2023 International Photonics and Optoelectronics Meetings (ACP/POEM), 2023Conference paper, Published paper (Refereed)
Abstract [en]

We demonstrate a beam-scannable photonic terahertz-integrated sensing and communication (THz-ISAC) system using Risley prisms. 20 Gbps data rate and 1.5 cm resolution are simultaneously achieved at 300 GHz with 40 deg field of view (FoV).

National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:ri:diva-70058 (URN)10.1109/ACP/POEM59049.2023.10368958 (DOI)
Conference
2023 Asia Communications and Photonics Conference/2023 International Photonics and Optoelectronics Meetings (ACP/POEM)
Note

This work is supported by the National Key Research and Development Program of China (2022YFB2903800) and “Pioneer” and “Leading Goose” R&D Program of Zhejiang 2023C01139, in part by the Natural National Science Foundation of China under Grant 62101483, the Natural Science Foundation of Zhejiang Province under Grant LQ21F010015, and the Fundamental research funds for the Zhejiang Lab (no. 2020LC0AD01).

Available from: 2024-01-17 Created: 2024-01-17 Last updated: 2024-01-17Bibliographically approved
Zhang, J., Yu, X., Bobrovs, V., Pang, X., Ozolins, O. & Zhang, L. (2023). Analysis and Compensation of Nonlinear Dynamics in Optical Fiber Transmission with the Optoelectronic Reservoir Computing. In: 2023 Photonics Global Conference (PGC): . Paper presented at 2023 Photonics Global Conference (PGC) (pp. 12-16).
Open this publication in new window or tab >>Analysis and Compensation of Nonlinear Dynamics in Optical Fiber Transmission with the Optoelectronic Reservoir Computing
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2023 (English)In: 2023 Photonics Global Conference (PGC), 2023, p. 12-16Conference paper, Published paper (Refereed)
Abstract [en]

Optical fiber communication systems play an important role in broadband signal transmissions, where the nonlinear dynamics in the long-haul optical fiber transmissions greatly degrade the transmission performance and limit the fiber capacity and reach. This paper analyzes and compensates for the nonlinear dynamics in the long-haul optical fiber transmission with the delay-based optoelectronic reservoir computing (RC) scheme, which provides benefits like time-adaptive tracking, low-complexity and hardware implementation potentials. The generalization of the analysis and compensation schemes from the traditional amplitude-modulated PAM signal to the amplitude-phase-modulated QAM signal is achieved by signal preprocessing. In the numerical study, the proposed RC-based fiber dynamics compensation scheme, with fiber reach from 1400km to 3000km, shows considerable performance with the digital backpropagation scheme, which is always used as the benchmark for nonlinear compensation of long-haul fiber transmissions. The realization complexity is much reduced with the RC-based schemes, which has provided a new dawn for optics-based nonlinear analysis and compensations.

National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:ri:diva-70028 (URN)10.1109/PGC60057.2023.10344084 (DOI)
Conference
2023 Photonics Global Conference (PGC)
Note

National Key Research and Development Program of China (2022YFB2903800); National Natural Science Foun-dation of China (62101483); Natural Science Foundation of Zhejiang Province (LQ21F010015); Zhejiang Lab (2020LC0AD01); Vetenskapsrådet (2019-05197) 

Available from: 2024-01-18 Created: 2024-01-18 Last updated: 2024-01-18Bibliographically approved
Puerta, R., Joharifar, M., Schatz, R., Djupsjöbacka, A., Ostrovskis, A., Sun, Y.-T. -., . . . Pang, X. (2023). Coherent Joint Transmission with 1024-QAM for 6G Distributed-MIMO Networks with Analog Radio-over-LWIR FSO Fronthaul Links. In: 2023 Asia Communications and Photonics Conference/2023 International Photonics and Optoelectronics Meetings (ACP/POEM): . Paper presented at 2023 Asia Communications and Photonics Conference/2023 International Photonics and Optoelectronics Meetings (ACP/POEM).
Open this publication in new window or tab >>Coherent Joint Transmission with 1024-QAM for 6G Distributed-MIMO Networks with Analog Radio-over-LWIR FSO Fronthaul Links
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2023 (English)In: 2023 Asia Communications and Photonics Conference/2023 International Photonics and Optoelectronics Meetings (ACP/POEM), 2023Conference paper, Published paper (Refereed)
Abstract [en]

Distributed-MIMO (D-MIMO) is a prospective solution for next-generation mobile networks to increase capacity and coverage. We experimentally validate 1024-QAM coherent joint transmissions in a two transmitter D-MIMO network including radio-over-LWIR FSO fronthaul links facilitating deployment and achieving diversity and power gains close to theoretical values.

National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:ri:diva-70046 (URN)10.1109/ACP/POEM59049.2023.10369145 (DOI)
Conference
2023 Asia Communications and Photonics Conference/2023 International Photonics and Optoelectronics Meetings (ACP/POEM)
Note

This work is supported by the Swedish Foundation for Strategic Research (SM21-0047), EU H2020 cFLOW Project (828893), Swedish Research Council (VR) projects 2019–05197 and 2022–04798, VINNOVA funded project (2023–00659), COST Action CA19111 NEWFOCUS, and RRF project Latvian Quantum Technologies Initiative (2.3.1.1.i.0/1/22/I/CFLA/001).

Available from: 2024-01-17 Created: 2024-01-17 Last updated: 2024-01-17Bibliographically approved
Han, M., Wang, M., Fan, Y., Salgals, T., Louchet, H., Schatz, R., . . . Ozolins, O. (2023). Deep Reservoir Computing for 100 Gbaud PAM6 IM/DD Transmission Impairment Mitigation. In: Opt. Fiber Commun. Conf. Exhib., OFC - Proc.: . Paper presented at 2023 Optical Fiber Communications Conference and Exhibition, OFC 2023San Diego5 May 2023through 9 May 2023. Institute of Electrical and Electronics Engineers Inc.
Open this publication in new window or tab >>Deep Reservoir Computing for 100 Gbaud PAM6 IM/DD Transmission Impairment Mitigation
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2023 (English)In: Opt. Fiber Commun. Conf. Exhib., OFC - Proc., Institute of Electrical and Electronics Engineers Inc. , 2023Conference paper, Published paper (Refereed)
Abstract [en]

We experimentally evaluate a deep Reservoir Computing (RC)-based post-equalization for 100 Gbaud PAM6 IM/DD transmissions. It achieves ∼1 dB higher sensitivity than DFE, and ∼50% implementation complexity reduction compared with the conventional RC configuration.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers Inc., 2023
Keywords
Complexity reduction, Deep reservoirs, High sensitivity, Impairment mitigation, Implementation complexity, Post-equalization, Reservoir Computing, Transmission impairment, Pulse amplitude modulation
National Category
Telecommunications
Identifiers
urn:nbn:se:ri:diva-65546 (URN)10.23919/OFC49934.2023.10116807 (DOI)2-s2.0-85161305520 (Scopus ID)
Conference
2023 Optical Fiber Communications Conference and Exhibition, OFC 2023San Diego5 May 2023through 9 May 2023
Note

This work was supported by the National Natural Science Foundation of China (U2006217, 61775015), the China Scholarship Council (202107090113), the National Key Research and Development Program of China (2018YFB1801500), the Swedish Research Council (VR) projects 2019-05197, the H2020 ICT TWILIGHT Project (No. 781471), the ERDF-funded RINGO project (No. 1.1.1.1/21/A/052), and the RTU Science Support Fund. We thank Keysight Technologies for the loan of the M8199A Arbitrary Waveform Generator and the UXR1104A Infiniium UXR-Series Oscilloscope.

Available from: 2023-06-30 Created: 2023-06-30 Last updated: 2023-06-30Bibliographically approved
Puerta, R., Joharifar, M., Han, M., Djupsjöbacka, A., Bobrovs, V., Popov, S., . . . Pang, X. (2023). Experimental Validation of Coherent Joint Transmission in a Distributed-MIMO System with Analog Fronthaul for 6G. In: 2023 Joint European Conference on Networks and Communications & 6G Summit (EuCNC/6G Summit): . Paper presented at 2023 Joint European Conference on Networks and Communications & 6G Summit (EuCNC/6G Summit) (pp. 585-590). Institute of Electrical and Electronics Engineers (IEEE)
Open this publication in new window or tab >>Experimental Validation of Coherent Joint Transmission in a Distributed-MIMO System with Analog Fronthaul for 6G
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2023 (English)In: 2023 Joint European Conference on Networks and Communications & 6G Summit (EuCNC/6G Summit), Institute of Electrical and Electronics Engineers (IEEE), 2023, p. 585-590Conference paper, Published paper (Refereed)
Abstract [en]

The sixth-generation (6G) mobile networks must increase coverage and improve spectral efficiency, especially for cell-edge users. Distributed multiple-input multiple-output (D-MIMO) networks can fulfill these requirements provided that transmission/reception points (TRxPs) of the network can be synchronized with sub-nanosecond precision, however, synchronization with current backhaul and fronthaul digital interfaces is challenging. For 6G new services and scenarios, analog radio-over-fiber (ARoF) is a prospective alternative for future mobile fronthaul where current solutions fall short to fulfill future demands on bandwidth, synchronization, and/or power consumption. This paper presents an experimental validation of coherent joint transmissions (CJTs) in a two TRxPs D-MIMO network where ARoF fronthaul links allow to meet the required level of synchronization. Results show that by means of CJT a combined diversity and power gain of +5 dB is realized in comparison with a single TRxP transmission.

Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE), 2023
National Category
Electrical Engineering, Electronic Engineering, Information Engineering
Identifiers
urn:nbn:se:ri:diva-66228 (URN)10.1109/eucnc/6gsummit58263.2023.10188222 (DOI)
Conference
2023 Joint European Conference on Networks and Communications & 6G Summit (EuCNC/6G Summit)
Note

This project is financially supported by the Swedish Foundation for Strategic Research (project No. SM21-0047). Also, it is supported in part by the Swedish Research Council (VR) project 2019–05197 and Vinnova project 2022–02545 (A-FRONTHAUL).

Available from: 2023-09-08 Created: 2023-09-08 Last updated: 2023-09-08Bibliographically approved
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Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-9839-7488

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