Alexei N. Pilipetskii

Transmission of 96×100G pre-filtered PDM-RZ-QPSK channels with 300% spectral efficiency over 10,608km and 400% spectral efficiency over 4,368km

We transmitted 96 × 100 G pre-filtered PDM-RZ-QPSK channels with 300% spectral efficiency over 10,608 km using 52 km spans of 150 μm2 fiber and simple single-stage EDFAs. We also achieved 400% spectral efficiency over 4,368 km using similar techniques.

112×112 Gb/s transmission over 9,360 km with channel spacing set to the baud rate (360% spectral efficiency)

We transmit 112×112 Gb/s pre-filtered PDM RZ-QPSK channels with 360% spectral efficiency over 9,360km with the channel spacing set to the baud rate. This results in a record spectral efficiency for transpacific distance.

Cycle slip mitigation in POLMUX-QPSK modulation

We demonstrate a pilot-symbol assisted joint polarization carrier phase estimation technique that detects cycle slip and avoid error propagation. Coherent detection without differential coding is feasible when the cycle slip probability is less than 10−3.

High spectral efficiency long-haul transmission with pre-filtering and maximum a posteriori probability detection

We propose a high spectral efficiency transmission scheme employing tight pre-filtering and maximum-a-posteriori-probability (MAP) detection. We demonstrate that pre-filtering induced inter-symbol-interference can be effectively compensated with MAP detection after transoceanic transmission.

Spectral efficiency limits of pre-filtered modulation formats

We investigate the spectral efficiency (SE) limit of pre-filtered modulation in optical fiber communication systems. We show that pre-filtering induced symbol correlation generates a modulation with memory and, thus, a higher SE limit than that of the original memoryless modulation. The SE limits of a series of modulation formats with varying number L of correlated symbols producing 50% of the original bandwidth are evaluated, which approach the SE limit of a modulation format with 50% pre-filtering as L --> ∞. We show that the SE limit of a modulation format with L correlated symbols approximates a lower bound for the SE limit of the corresponding pre-filtered format.

On channel models for predicting soft-decision error correction performance in optically amplified systems

We investigate three channel models for optically amplified systems employing soft-decision decoding. We show that the additive white Gaussian noise model can be a proper model for error-correction performance prediction but not for error-correction implementation in noise-limited optical fiber channels.

Coherent 40 Gb/s transmission with high spectral efficiency over transpacific distance

We experimentally study the reach of coherent 40 Gb/s PDM RZ QPSK transmission at several spectral efficiencies. Transpacific transmission distance at 3.2 bits/s/Hz and record SE-distance product at 2.4 bits/s/Hz are demonstrated.

Achieving high spectral efficiency in long-haul transmission with pre-filtering and multi-symbol detection

We investigate a high spectral efficiency transmission approach employing aggressive pre-filtering and multi-symbol detection. We show that pre-filtering induces symbol correlation thus enabling a higher spectral-efficiency limit than that of the original modulation format. We demonstrate 100G transoceanic transmission at 419% spectral efficiency using this approach.

High Capacity Ultralong-Haul Power Efficient Transmission Using 12-Core Fiber

We use multicore fiber to demonstrate power efficient, high capacity ultralong-haul spatial division multiplexing (SDM) transmission. Feasibility of 105.1xa0Tb/s transmission over 14,350xa0km in a 12-core fiber is shown using a power efficient modulation format and an optimized optical system design. Pump power equivalent to a single 800xa0mW laser is used to provide amplification for all 12 SDM paths.