Dayou Qian

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.

Centralized Lightwave WDM-PON Employing 16-QAM Intensity Modulated OFDM Downstream and OOK Modulated Upstream Signals

We have proposed and experimentally demonstrated a novel architecture for orthogonal frequency-division- multiplexing (OFDM) wavelength-division-multiplexing passive optical network with centralized lightwave. In this architecture, 16 quadrature amplitude modulation intensity-modulated OFDM signals at 10 Gb/s are utilized for downstream transmission. A wavelength-reuse scheme is employed to carry the upstream data to reduce the cost at optical network unit. By using one intensity modulator, the downstream signal is remodulated for upstream on-off keying (OOK) data at 2.5 Gb/s based on its return-to-zero shape waveform. We have also studied the fading effect caused by double-sideband (DSB) downstream signals. Measurement results show that 2.5-dB power penalty is caused by the fading effect. The fading effect can be removed when the DSB OFDM downstream signals are converted to single sideband (SSB) after vestigial filtering. The power penalty is negligible for both SSB OFDM downstream and the remodulated OOK upstream signals after over 25-km standard single-mode-fiber transmission. Index

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.

1.05Pb/s Transmission with 109b/s/Hz Spectral Efficiency using Hybrid Single- and Few-Mode Cores

We demonstrated 1.05-Pb/s transmission over 3km of multicore fiber with spectral efficiency of 109b/s/Hz, using twelve single-mode cores carrying DP-32QAM-OFDM signals and two few-mode cores carrying DP-QPSK in their LP01 and two LP11 modes.

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.