Junqiang Hu

108 Gb/s OFDMA-PON With Polarization Multiplexing and Direct Detection

In this paper, we propose and experimentally demonstrate the first single-¿ 40 Gb/s and 108 Gb/s multiple-input multiple-output orthogonal frequency-division multiple access (OFDMA) passive optical networks (PON) architecture for next-generation PON systems based on OFDM, polarization multiplexing (POLMUX), and direct detection. Superior performance was exhibited after 20 km SSMF transmission and a 1:32 optical split. The novel POLMUX approach greatly simplified receiver-end hardware compared to coherent detectors, while increasing spectral efficiency to enable 40+ Gb/s data rates. Moreover, the proposed solution achieved the highest single-wavelength downstream transmission reported to date in any PON system. As such, the introduced architecture may be viewed as a highly attractive candidate for next-generation optical access.

101.7-Tb/s (370×294-Gb/s) PDM-128QAM-OFDM transmission over 3×55-km SSMF using pilot-based phase noise mitigation

Record capacity transmission of 101.7-Tb/s (370×294-Gb/s) is performed over 3×55 km SSMF using PDM-128QAM-OFDM modulation and pilot-based phase noise mitigation. Achieved spectral efficiency of 11 bits/s/Hz is the highest reported to date for WDM transmission.

146λ × 6 × 19-Gbaud Wavelength-and Mode-Division Multiplexed Transmission Over 10 × 50-km Spans of Few-Mode Fiber With a Gain-Equalized Few-Mode EDFA

We demonstrate wavelength- and mode-division multiplexed transmission over a fiber re-circulating loop comprising 50-km of low-DMGD few-mode fiber, and an optimized few-mode EDFA with reduced wavelength-dependent gain and mode-dependent gain. We characterize the channel matrix in terms of its singular value spread, and investigate its long-term stability.

100 Gb/s optical access based on optical orthogonal frequency-division multiplexing

The ever-increasing bandwidth demand in access systems is catalyzing research and development activity in future ultra high-speed 100 Gb/s passive optical networks. In this article we discuss the principles, key advantages, and most recent demonstrations of a record 100 Gb/s OFDM-based PON as a future PON candidate architecture. Moreover, we provide an analysis of primary cost factors in a practical DSP-based OFDMA-PON implementation and survey the most recent achievements in this domain. Due to the combination of highly attractive advanced features and favorable related trends in longhaul 100 Gb/s fiber transmission, OFDMA-PON can be regarded as a very promising solution for future PON-based access.

Orthogonal frequency division multiple access PON (OFDMA-PON) for colorless upstream transmission beyond 10 Gb/s

In this paper, we overview the fundamental principles of next-generation optical Orthogonal Frequency Division Multiple Access (OFDMA)-PON systems, with a particular focus on upstream architectures capable of achieving 10+ Gb/s colorless upstream transmission. We also propose a novel OFDMA-PON architecture that satisfies these requirements and is capable of exceeding 10 Gb/s upstream transmission over a single wavelength. It is first analytically shown that optical carrier suppression at the optical network units (ONUs) combined with coherent detection at the optical line terminal (OLT) successfully eliminates both in- and cross-polarization beating noise that would otherwise be generated at the OLT and would fundamentally limit upstream transmission performance. A centralized light source OFDM-based PON architecture with source-free ONUs and OLTside coherent detection is then presented and experimentally verified to achieve 20 Gb/s/λ transmission over a class B+ optical distribution network (20 km SSMF with an additional 1:32 optical split.) By thus providing very high-speed, flexible, colorless upstream transmission, the proposed architecture is an attractive candidate for next-generation PON systems capable of cost-efficiently delivering heterogeneous services.

A Novel OFDMA-PON Architecture With Source-Free ONUs for Next-Generation Optical Access Networks

This letter proposes a novel architecture for next-generation passive optical networks based on the employment of orthogonal frequency-division multiple access. The key new feature of the proposed approach is source-free single-wavelength upstream transmission enabled by carrier suppression, which has been experimentally verified to achieve 10-Gb/s upstream throughput.

High Capacity/Spectral Efficiency 101.7-Tb/s WDM Transmission Using PDM-128QAM-OFDM Over 165-km SSMF Within C- and L-Bands

We experimentally demonstrate 101.7-Tb/s transmission over 355 km spans of standard single-mode fiber (SSMF) at a net spectral efficiency of 11 b/s/Hz. A total of 370 dense wavelength-division multiplexed (DWDM) channels spanning the optical C- and L-bands spaced at 25 GHz were used. Each 25-GHz channel were subdivided into four subbands, with each subband carrying a 73.5-Gb/s orthogonal frequency-division multiplexed (OFDM) signal modulated with polarization-division-multiplexing (PDM) 128-ary quadrature amplitude modulation (QAM) at each modulated subcarrier. This experiment was enabled by digital signal processing (DSP) pre-equalization of transmitter impairments, all Raman amplification, heterodyne coherent detection, and DSP postequalization of the channel and receiver impairments, including pilot-based phase noise compensation.

10-Gb/s OFDMA-PON for Delivery of Heterogeneous Services

We propose a novel method to generate transparent pipes for transmission of heterogeneous services over 10-Gb/s OFDMA-PON architecture. We successfully demonstrated the simultaneous transmission of two PON channels combined with a standard WiMAX channel.

108 Gb/s OFDMA-PON with polarization multiplexing and direct-detection

The first single-λ 108-Gb/s 16QAM-OFDMA-PON is demonstrated using polarization-multiplexed optical OFDM and direct-detection. This is the highest single-λ downstream rate in PON reported to date, achieved over 20 km SSMF and a 1:32 split.

MAC Protocols for Optical Orthogonal Frequency Division Multiple Access (OFDMA)-based Passive Optical Networks

A novel passive optical network (PON) architecture based on optical orthogonal frequency division multiple access (OFDMA) technologies is presented. Two potential medium access control (MAC) methods namely dynamic circuit transmission and fixed burst transmission are investigated.