Andrew Adamiecki

100-Gb/s DQPSK Transmission: From Laboratory Experiments to Field Trials

We discuss the generation, detection, and long-haul transmission of single-polarization differential quadrature phase shift keying (DQPSK) signals at a line rate of 53.5 Gbaud to support a net information bit rate of 100 Gb/s. In the laboratory, we demonstrate 10-channel wavelength-division multiplexed (WDM) point-to-point transmission over 2000 km on a 150-GHz WDM grid, and 1200-km optically routed networking including 6 reconfigurable optical add/drop multiplexers (ROADMs) on a 100-GHz grid. We then report transmission over the commercial, 50-GHz spaced long-haul optical transport platform LambdaXtremereg. In a straight-line laboratory testbed, we demonstrate single-channel 700-km transmission, including an intermediate ROADM. On a field-deployed, live traffic bearing Verizon installation between Tampa and Miami, Florida, we achieve 500-km transmission, with no changes to the commercial system hardware or software and with 6 dB system margin. On the same operational system, we finally demonstrate 100-Gb/s DQPSK encoding on a field-programmable gate array (FPGA) and the transmission of real-time video traffic.

High-speed electrical backplane transmission using duobinary signaling

High-speed electrical data transmission through low-cost backplanes is a particularly challenging problem. We present for the first time a very effective approach that uses the concept of duobinary signaling to accomplish this task. Using a finite-impulse-response filter, we are able to compensate for the phase and amplitude response of the backplane such that the resulting frequency response of the channel is that of an ideal duobinary filter. At the output of the backplane, we use an innovative pseudodigital circuit to convert the electrical duobinary to binary. For 10-Gb/s data transmission, we demonstrate a bit error rate <10/sup -13/ through electrical backplane traces up to 34 in in length on FR4. A full discussion of the concept, system architecture, and measured results are presented. Analysis is presented that compares and contrasts this approach to PAM-4 and standard nonreturn-to-zero signaling.

Compensation of intra-channel nonlinearities in 40 Gb/s pseudo-linear systems using optical phase conjugation

We compensate intra-channel nonlinearities in an RZ-DPSK-40 Gb/s 32/spl times/100 km system using a LiNbO/sub 3/ conjugator and achieve 2 decades of improvement in BER. Transmission limited to 5200 km at a BER=5/spl times/10/sup -4/ is extended to 6400 km with phase conjugation.

Demonstration of the interconnection of two optical packet rings with a hybrid optoelectronic packet router

We demonstrate the interconnection of two optical packet switching systems: a hybrid optoelectronic packet router and two optical packet rings. Error-free inter-ring and intra-ring optical packet transmission and unicast and multicast transport of encapsulated 10 GbE are achieved.

High Symbol Rate Coherent Optical Transmission Systems: 80 and 107 Gbaud

We demonstrate high speed optical transmission systems using digital coherent detection at all-electronically multiplexed symbol rates of 80 and 107 Gbaud. At 107 Gbaud, we demonstrate a single-carrier polarization division multiplexed quadrature phase shift keyed (PDM-QPSK) line rate of 428 Gb/s. At 80 Gbaud, we achieve a single-carrier line rate of 640 Gb/s using PDM 16-ary quadrature amplitude modulation (16-QAM). Using two optical subcarriers, we demonstrate a 1-Tb/s optical interface and conduct long-haul wavelength-division multiplexed (WDM) transmission on a 200-GHz grid over 3200 km of ultra-large effective area fiber.

RZ-DPSK transmission using a 42.7-Gb/s integrated balanced optical front end with record sensitivity

We have demonstrated a record sensitivity of -37.0 dBm (38 photons/bit) for a BER of 10/sup -9/ at 42.7-Gb/s using an integrated balanced optical front end. Results were obtained using optical preamplification of RZ-DPSK modulation and an external delay-interferometer. The OSNR requirement was measured to be 16.9 dB in a 0.1-nm bandwidth. The impact of polarization-mode dispersion (PMD) and chromatic dispersion on the optical front end performance has been measured. Performance for enhanced forward error correction has been projected based on 10/sup -3/ BER performance.

1705-km transmission over coupled-core fibre supporting 6 spatial modes

We present experimental transmission results for a novel 6-core coupled-core fibre with 125 μm cladding diameter. We transmit combined 2-polarization, 6-SDM and 30-WDM channels over a distance of 1705 km, with a spectral-efficiency-distance product of 30690 bit/s/Hz km.

A 107-Gbit/s Optoelectronic Receiver Utilizing Hybrid Integration of a Photodetector and Electronic Demultiplexer

A novel 107-Gbit/s optoelectronic receiver has been designed using hybrid integration of a photodiode and electronic demultiplexer. Using an ETDM transmitter, we achieve the lowest reported required OSNR for 107-Gbit/s CSRZ-OOK, 21 dB for 10-3 BER and a 231-1pattern length. Design methodology and performance data are presented.

A 40-Gb/s integrated balanced optical front end and RZ-DPSK performance

We have designed and built an integrated balanced optical front end suitable for detecting RZ-DPSK transmissions when used with an external delay-interferometer. We have achieved an optically preamplified sensitivity of -35.7 dBm at a BER of 10/sup -9/ and an optical signal-to-noise ratio of 18.3 dB in a 0.1-nm bandwidth at 40 Gb/s. To the best of our knowledge, this is the first demonstration of 40-Gb/s RZ-DPSK reception with an integrated hybrid optical front end.

305-km combined wavelength and mode-multiplexed transmission over conventional graded-index multimode fibre

We present experimental results for mode-multiplexed WDM transmission over OM3 multimode fibres. We transmit 60 WDM channels and 3 spatial modes over a distance of 305 km. We use mode-selective photonic lanterns as mode couplers and for differential group delay compensation.