W. Poehlmann

10.2 Tbit/s (256x42.7 Gbit/s PDM/WDM) transmission over 100 km TeraLight/sup TM/ fiber with 1.28 bit/s/Hz spectral efficiency

We demonstrate the transmission of 256 polarization-division and wavelength-division multiplexed channels at 42.7 Gbit/s rate over 100 km of TeraLight/sup TM/ fiber. An overall capacity of 10 Tbit/s is achieved in C and L bands at a record 1.28 bit/s/Hz spectral efficiency.

Beneficial OLT transmitter and receiver concepts for NG-PON2 using semiconductor optical amplifiers [invited]

Optical line termination transmitter (Tx) and receiver (Rx) concepts using a semiconductor optical amplifier (SOA) for the next generation of passive optical networks (NG-PON2) are experimentally compared. In general, a single SOA per wavelength channel at the Tx and a configuration comprising a single SOA followed by avalanche photodiodes (APDs) at the Rx are beneficial in terms of signal quality and power dynamic range. Additionally, we introduce a cost-effective bidirectional SOA approach for simultaneous upstream preamplification and downstream boosting. Our results indicate its feasibility for mid-class loss budget classes of NG-PON2.

Demonstration of an SOA-assisted open metro-access infrastructure for heterogeneous services

An open converged metro-access network approach allows for sharing optical layer resources like fibers and optical spectrum among different services and operators. We demonstrated experimentally the feasibility of such a concept by the simultaneous operation of multiple services showing different modulation formats and multiplexing techniques. Flexible access nodes are implemented including semiconductor optical amplifiers to create a transparent and reconfigurable optical ring network. The impact of cascaded optical amplifiers on the signal quality is studied along the ring. In addition, the influence of high power rival signals in the same waveband and in the same fiber is analyzed.

Amplification of advanced modulation formats with a semiconductor optical amplifier cascade.

The convergence of optical metro networks and access networks extends the area of network coverage, and therefore requires the use of optical amplifiers. For this purpose, semiconductor optical amplifiers (SOA) would be attractive, because they are broadband, can be centered between 1250 nm and 1600 nm, and because they are cheap in production and operation. We show that signals encoded with advanced modulation formats such as BPSK, QPSK, 8PSK, and 16QAM can be amplified by a cascade of at least four SOAs. This enables high-capacity paths with a capacity in the order of Tbit/s for converged metro-access networks.

Wavelength drift of burst-mode DML for TWDM-PON [invited]

Thermally tunable burst-mode directly modulated lasers (DMLs) are the lowest-cost choices for the optical network units in time and wavelength division multiplexed passive optical network (TWDM-PON) systems. However, a fast wavelength drift caused by the burst-mode operation of this directly modulated distributed feedback laser needs to be considered. The drift can result in power penalties by effectively reducing the received optical power and also in crosstalk penalties when the signal drifts into neighboring channels after passing through the wavelength division multiplexed filter. In this paper, we report measurements and mitigation methods for this unwanted wavelength drift.

Cross-talk analysis & mitigation for TWDM-PON upstream path

Various cases of cross-talk mechanisms occurring in a TWDM-PON are analyzed in simulations and experiments. Power penalty degradations and limitations of photonic component technologies are described and mitigation techniques enabling such NG-PON2 systems are introduced.

Wavelength-transparent long-reach-high-split TWsDM-PON utilized by a non-gated parallel cascade of linear SOAs

We demonstrate the first long-reach and high-split TWsDM-PON utilizing a non-gated parallel cascade of linear SOAs. A fiber reach of up to 100 km and up to 2048 customers are achieved in non-wavelength routed outside plants.

10 Gbps / 2.5Gbps GPON coexistence by downstream bit-stacking

Gigabit PON /10 Gbps PON coexistence with two ONU generations on a single 1490 nm downstream wavelength is enabled by bitstacking and affiliated framing measures forming a novel electrical multiplexing technique.

Optical line termination transceiver with a bi-directional SOA for application in type-A NG-PON2 links

The first NG-PON2 type-A-link OLT transceiver comprising a bi-directional SOA is experimentally assessed. Sufficient downstream transmitter output power and upstream receiver sensitivity is simultaneously demonstrated for E2 budget class. The influence of filter bandwidth and APD / PIN receiver is investigated.

Physical media dependent challenges in US path of space and service converged TWDM-PON

An overview of PMD challenges in the upstream path of space and service converged TWDM-PON is provided. Simulations and experiments examine interrelations of loss budget, OSNR, dispersion, cross-talk, laser frequency-drifts and co-existence of services.