工業無源光網絡物理層關鍵技術及發展趨勢

霍佳皓; 張曉營; 高凱強; 皇甫偉; 隆克平

doi:10.13374/j.issn2095-9389.2022.12.14.001

工業無源光網絡物理層關鍵技術及發展趨勢

doi: 10.13374/j.issn2095-9389.2022.12.14.001

1.
北京市融合網絡與泛在業務工程中心，北京科技大學，北京 100083
2.
中國電力科學研究院有限公司，北京 100192

基金項目: 國家重點研發計劃資助項目（ 2021YFB2900801）；國家自然科學基金資助項目（62201033, U22A2005）；中國通信學會青年人才托舉工程（2021QNRC001）；廣東省基礎與應用基礎研究基金聯合基金?青年基金資助項目（2020A1515111047）；青年教師國際交流成長計劃（QNXM20220039）

詳細信息

通訊作者:
E-mail: huojiahao@ustb.edu.cn

中圖分類號: TN911
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- 被引次數: 0
出版歷程
- 收稿日期: 2022-12-14
- 網絡出版日期: 2023-04-04
- 刊出日期: 2023-10-25

Key technologies and trends in the development of industrial passive optical networks

1.
Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services, University of Science and Technology Beijing, Beijing 100083, China
2.
China Electric Power Research Institute, Beijing 100192, China

More Information

Corresponding author: E-mail: huojiahao@ustb.edu.cn

摘要

摘要: 隨著工業互聯網的不斷發展，工業無源光網絡（Passive optical network，PON）引起了工業界和學術界的共同關注. 為應對工業互聯網多樣化場景應用的不同特點，工業PON需滿足超高速率、超大連接和低成本的需求，物理層調制格式、復用方式、傳輸方案、數字信號處理算法等一直是該領域的研究熱點. 首先介紹了PON的基本概念，回顧了PON的標準化歷程，重點對PON物理層傳輸方案及關鍵技術進行梳理，包含強度調制技術、多維復用技術和數字均衡技術的研究進展. 然后，提出了適用于工業PON傳輸的偏振復用強度調制相干檢測系統方案，在仿真平臺上分別測試了四電平脈沖幅度調制和開關鍵控調制兩種調制格式在背靠背和20 km傳輸距離的單模光纖中的傳輸性能，驗證了該方案的優越性. 最后，對工業PON的物理層發展趨勢進行展望.
- 工業PON /
- 超高速率 /
- 超大連接 /
- 低成本 /
- 數字均衡技術
Abstract: With the proliferation of the industrial internet, passive optical networks (PON) have attracted attention from industry and academia. Industrial PONs need to meet the requirements of ultra-high speed, ultra-large connections, and low cost to be able to cope with diverse industrial internet scenarios. Physical layer modulation formats, multiplexing modes, transmission schemes, and digital signal processing algorithms have always been the focus of research in this field. Direct detection and 10 G devices are extensively studied due to their low cost and ease of deployment. However, meeting the power budget targets of a high-speed PON can be challenging. Transmission of a high-order modulation signal can improve the system’s capacity; however, it may also decrease the receiver’s sensitivity. Polarization multiplexing technology, coherent detection, and advanced digital signal processing technology can be utilized to meet the demands of industrial PON, such as ultra-high speeds, ultra-large connections, ultra-high capacities, high receiver sensitivity, and high power budgets. The use of intensity modulation schemes at the transmitter would reduce the overall cost of the system. Herein, we propose a digital coherent detection system with polarization multiplexing intensity modulation suitable for industrial PON transmission. The 50 Gbit·s^?1 signals modulated with four-level pulse amplitude modulation (PAM 4) and on–off keying (OOK) are transmitted on the simulation platform. Performance assessments of back to back (BTB) transmission and fiber transmission over 20 km are studied to prove the superiority of this proposed scheme. A power budget of more than 32 and 36 dB can be achieved with the polarization multiplexing coherent detection system-based transmission of 50 Gbit·s^?1 PAM 4 and NRZ signals, respectively, on a 20 km C-band single-mode fiber at a threshold of 3.8×10^?3, which is a considerable improvement over intensity modulation direct detection systems. The superiority of the proposed scheme is further verified by the fact that the 100 Gbit·s^?1 PAM 4 signal has better transmission performance in the polarization multiplexing intensity modulation coherent detection system than the NRZ signal. Considering the system performance, the polarization multiplexing intensity modulation coherent detection scheme is expected to be one of the promising solutions for high-speed PON systems. Finally, the development trends of the physical layer of industrial PON are discussed.
- industrial PON /
- ultra-high speed /
- ultra-large connection /
- low cost /
- digital equalization technique

HTML全文

圖 1 簡化的相干系統方案. (a) IQ交錯檢測接收機架構；(b)自零差相干系統架構

Figure 1. Simplified coherent system scheme: (a) configuration of the IQ-interleaved coherent detection scheme; (b) configuration of the self-homodyne coherent scheme

Notes: ADC is analog to digital converter; E_CW(t) is field of continuous wave; E_S(t) is field of signal; E_LO(t) is field of local oscillator; RX is receiver.

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圖 2 FLCS-PON在大范圍PON中的實現圖

Figure 2. Implementation diagram of the FLCS-PON in a large-scale PON

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圖 3 傳統PON與FLCS-PON比較^[26]

Figure 3. Comparison of traditional PON with FLCS-PON ^[26]

Notes: DRNRP is dynamic-range and net-rate product; CPON is coherent passive optical network.

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圖 4 基于多芯光纖的上下行傳輸方案

Figure 4. Scheme of upstream and downstream transmissions over a multicore fiber

Notes: MCF is multi-core fiber

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圖 5 文獻[44]和[47]中有無SOA的結果比較. (a)文獻[44]; (b)文獻[47]

Figure 5. Comparison of the results with and without SOA: (a) in reference [44]; (b) in reference [47]

Notes: BER—Bit error ratio; OMA—Optical modulation amplitude; btb—back to back; w/—with; w/o—without

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圖 6 突發模式接收機結構

Figure 6. Configuration of the burst mode receiver

Notes: AGC-EDFA is automatic gain controlled erbium-doped fiber amplifier; ALC is automatic level control; ICR is integrated coherent receiver.

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圖 7 上行突發模式DSP框圖

Figure 7. Block diagram of digital signal processing in the burst mode of transmission

Notes: SOP is state of polarization

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圖 8 偏振復用相干探測系統實驗設置

Figure 8. Experimental setup of PDM-PAM4 with the coherent system

Notes: PBS is polarization beam splitter; AWG is arbitrary-waveform generator; PBC is polarization beam combiner

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圖 9 下行DSP處理框圖

Figure 9. Offline DSP blocks of signal recovery

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圖 10 BER與信號接收光功率的關系曲線圖. (a) 50 Gbit·s^?1 NRZ; (b) 50 Gbit·s^?1 PAM 4; (c) 100 Gbit·s^?1 NRZ; (d) 100 Gbit·s^?1PAM 4

Figure 10. BER as a function of the received optical power: (a) 50 Gbit·s^?1 NRZ; (b) 50 Gbit·s^?1 PAM 4; (c) 100 Gbit·s^?1 NRZ; (d) 100 Gbit·s^?1 PAM 4

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