Flexible Coherent Optical Access: Architectures, Algorithms, and Demonstrations

Journal of Lightwave Technology, Год журнала: 2024, Номер 42(4), С. 1193 - 1202

Опубликована: Янв. 18, 2024

To cope with the explosive bandwidth demand, significant progress has been made in ITU-T standardization sector to define a higher-speed passive optical network (PON) 50 Gb/s line rate. Recently, G PON become mature gradually, which means it is time discuss beyond PON. For ensuring an acceptable power budget, will potentially use coherent technologies, can simultaneously promote applications of flexible multiple access such as time/frequency-domain (TFDMA). In this paper, we introduce architectures, algorithms, and demonstrations for TFDMA-based The system architectures based on ultra-simple transceiver specific signal spectra are designed reduce cost ONUs greatly. Meanwhile, continuous-mode burst-mode digital processing (DSP) algorithms proposed dealing downstream upstream signals, respectively. Based experimentally demonstrate first real-time where Gb/(s × subcarrier) continuous 12.5 burst processed real time. Owing independent subcarrier processing, potential support peak rates 200 (i.e. four subcarriers) 100 eight subcarriers). Significantly, have sufficiently verified by demonstrations. conclusion, technologies make more possible be applied future

Язык: Английский

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Experimental Demonstration of Rate-Flexible Coherent PON Up to 300 Gb/s

Journal of Lightwave Technology, Год журнала: 2024, Номер 42(16), С. 5440 - 5449

Опубликована: Фев. 15, 2024

We propose a novel rate flexible coherent passive optical network (PON) that features low complexity burst frame detection scheme to achieve modulation format selection. The proposed algorithm, along with preamble design for different formats are studied in detail. In laboratory experiment setting, the method allows an automated digital signal processing (DSP) workflow supports wide range of formats. Using scheme, two innovative rate-flexible PON architectures have been and experimentally demonstrated. One time-division multiplexing (TDM) three both downstream upstream transmission, other uses frequency comb-based multi-wavelength source broadcasting TDM upstream. experiments, 25-GBd dual-polarization quadrature phase shift keying (DP-QPSK), 16 amplitude (DP-16QAM), 64 (DP-64QAM) were examined. A peak data up 300 Gb/s transmission over 50 km fiber optic link split ratio 1×32 achieved, Tx power +5 dBm, Rx around -20 dBm.

Язык: Английский

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First Real-time Demonstration of 200G TFDMA Coherent PON using Ultra-simple ONUs

Optical Fiber Communication Conference (OFC) 2022, Год журнала: 2023, Номер unknown, С. Th4C.4 - Th4C.4

Опубликована: Янв. 1, 2023

We demonstrate the first real-time TFDMA coherent PON system with single-DAC and single-ADC ONUs, which can support up to 256 end users, peak line rates of 100/200 Gb/s in upstream/downstream, respectively.

Язык: Английский

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Low-cost, large-coverage, and high-flexibility coherent PON for next-generation access networks: advances, challenges, and prospects [Invited]

Chinese Optics Letters, Год журнала: 2024, Номер 22(4), С. 040604 - 040604

Опубликована: Янв. 1, 2024

Increasing bandwidth requirements have posed significant challenges for traditional access networks. It is difficult intensity modulation/direct detection to meet the power budget and flexibility of next-generation passive optical network (PON) at 100G beyond considering new requirements. This driving researchers develop novel technologies. Low-cost, wide-coverage, high-flexibility coherent PON emerging as a strong contender in competition. In this article, we will review technologies that reduce complexity (CPON), enabling it commercial Also, advanced algorithms architectures can enhance system coverage are also discussed.

Язык: Английский

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Joint frequency offset estimation and adaptive equalization for a coherent passive optical network

Chinese Optics Letters, Год журнала: 2025, Номер 23(4), С. 040602 - 040602

Опубликована: Янв. 1, 2025

Язык: Английский

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Highly robust and hardware-efficient frame synchronization and carrier recovery via pilot-only approaches for short-reach optical interconnections

Chinese Optics Letters, Год журнала: 2025, Номер 23(6), С. 060602 - 060602

Опубликована: Янв. 1, 2025

Язык: Английский

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Non-integer-oversampling digital signal processing for coherent passive optical networks

Journal of Optical Communications and Networking, Год журнала: 2023, Номер 16(1), С. 4 - 4

Опубликована: Ноя. 16, 2023

Beyond 100G passive optical networks (PONs) will be required to meet the ever-increasing traffic demand in future. Coherent technologies are competitive solutions for future beyond PON but also face challenges such as high computational complexity of digital signal processing (DSP). A oversampling rate coherent results DSP. Therefore, DSP running a non-integer-oversampling below 2 samples-per-symbol (sps) is preferred, which can not only reduce obviously lower requirement analog-to-digital converter. In this paper, we propose meeting requirements PON. Complexities complex-valued multiplication proposed working at 9/8-sps and 5/4-sps rates reduced by 44.04% 40.78% compared that 2-sps rate, respectively. 400-Gb/s-net-rate based on subcarrier multiplexing was demonstrated verify feasibility There almost no penalty receiver sensitivity when adopted. conclusion, shows great potential

Язык: Английский

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Demonstration of Pilot-Aided Continuous Downstream Digital Signal Processing for Multi-Format Flexible Coherent TDM-PON

Journal of Lightwave Technology, Год журнала: 2024, Номер 42(4), С. 1312 - 1320

Опубликована: Фев. 6, 2024

The coherent passive optical network (PON) is a promising solution for the next generation of high-speed access network, capable supporting 100G and beyond data rate. Moreover, flexibility adaptability PON (CPON) have attracted increasing interest. A flexible can enhance system throughput through adaptive modulation formats, baud rates, coding techniques. One critical challenge adaptive-modulation CPON need fast-tracking channel status, particularly downstream transmission. This important as signals with different formats are continuous in In present study, we proposed experimentally demonstrated pilot-aided digital signal processing (DSP) scheme 300 G based on 4/16/64-QAMs, which avoids burst-signal transmission during modulation-format switching. pilot symbols that insert enable tracking state-of-polarization, finite impulse response (FIR) coefficients equalization, carrier phase. feasibility DSP was verified four cases involving formats. As proof concept, achieved detection, enabling 100-300 We total power budgets 38, 30, 20 dB 25-GBaud polarization-division-multiplexed (PDM) 4/16/64-QAM after 20-km single-mode fiber (SMF), respectively.

Язык: Английский

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Investigating CRYSTALS-Kyber Vulnerabilities: Attack Analysis and Mitigation

Cryptography, Год журнала: 2024, Номер 8(2), С. 15 - 15

Опубликована: Апрель 19, 2024

Significant advancements have been achieved in the field of quantum computing recent years. If somebody ever creates a sufficiently strong computer, many public-key cryptosystems use today might be compromised. Kyber is post-quantum encryption technique that depends on lattice problem hardness, and it was recently standardized. Despite extensive testing by National Institute Standards Technology (NIST), new investigations demonstrated effectiveness CRYSTALS-Kyber attacks their applicability non-controlled environments. We investigated CRYSTALS-Kyber’s susceptibility to side-channel attacks. In reference implementation Kyber512, additional functions can compromised employing selected ciphertext. The ciphertext allows succeed. Real-time recovery entire secret key possible for all assaults.

Язык: Английский

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SkipNet: an adaptive neural network equalization algorithm for future passive optical networking

Journal of Optical Communications and Networking, Год журнала: 2024, Номер 16(11), С. 1082 - 1082

Опубликована: Июль 26, 2024

In this paper, we propose an original adaptive neural network equalizer (NNE) algorithm named SkipNet, which is suitable for rapid training on a packet-by-packet basis burst-mode non-linear equalization in upstream PON transmission. SkipNet uses the simple LMS and avoids complex algorithms such as backpropagation mini-batch training. We demonstrate captured continuous mode 100 Gbit/s PAM4 signals using SOA preamplifier to achieve challenging 29 dB optical loss budget. The shown overcome combinations of severe patterning effects fiber dispersion impairments >29dB dynamic range back-to-back >22.9dB up 81.6 ps/nm accumulated dispersion. It can adapt little 250 symbols each impairment scenario, equivalent existing FFE/DFE solutions, while matching performance previously proposed static NNE solutions. To best our knowledge, first ever framework that realistically be trained adapted within strict packet preamble lengths.

Язык: Английский

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