PBS-free Polarization-Independent PON Coherent Receiver

We introduce a coherent receiver that, without DSP and/or polarization coding at the transmitter, requires no Polarization Beam Splitter and still is polarization-independent. It is experimentally demonstrated at 10 Gbit/s with a sensitivity of −37.6 dBm at FEC level. It can also be operated at higher bit-rates and finds application in high-speed access and datacenter networks

Coherent PON system with high-sensitivity polarization-independent receiver and no ADC/DSP

A 1.25 Gb/s ASK PON system with -51dBm sensitivity (at BER=2-103) is enabled by a polarization-independent coherent receiver that needs no DSP (nor ADC). The system just uses common DFBs and commercial electronic devices and has 52 dB dynamic range

Hitless wavelength assignment in filterless optical access networks

Advantages offered by coherent detection systems in access networks are not limited to the increase of power budget due to the superior sensitivity. Channel selectivity is another intriguing feature offered by coherent systems that can be exploited to enable advanced system and network functionalities for access systems. Among them, we focus here on the implementation of filterless optical networks and network reconfiguration capabilities which might be required to satisfy dynamic load balancing requests and new terminal activations. We show that in the access domain these functionalities do not require DSP-aided coherent receivers, but can be easily realized by means of simpler, fully analogue real-time coherent terminals matching the access network low-cost paradigm. This paper discusses these concepts and how they can be experimentally implemented by using a novel wavelength allocation algorithm and real-time analogue coherent transceivers based on DFB lasers, whose wavelengths are tuned by a simple temperature control

Polarization-Independent Coherent Real-Time Analog Receiver for PON Access Systems

A 1.25-Gb/s ASK passive optical network (PON) system with a -51 dBm pre-FEC sensitivity (at BER = 2 × 10-3) is enabled by a real-time polarization-independent coherent receiver (PI-RX) that needs no DSP (nor ADC). The receiver, which only makes use of common DFBs and commercially available electronic ICs, is targeted for use on a 6.25-GHz UD-WDM grid and has a 52-dB dynamic range. Measurements of the robustness of the PI-RX against backreflections and crosstalk from coexistent adjacent channels show that this preliminary implementation is suitable for UD-WDM-PON systems with frequency spacing down to 5 GHz

Hitless dynamic wavelength allocation in coherent WDM-PONs

We introduce a novel algorithm for real-time ONU activation (lambda assignment and reconfiguration, lambda tuning) in WDM coherent PONs. The algorithm prevents service interruption of lighted channels and it is experimentally demonstrated by using real-time fully-analog coherent transceivers

4x10 Gb/s Coherent WDM-PON System over 110 km Single Mode Fibre and with 55 dB ODN Power Budget

Simplified coherent detection of directly modulated DFB transmitters allows for 55 dB ODN power budget in downstream of a 40 Gb/s DML-based WDM-PON with 110 km reach. The solution can enhance NGPON2, addressing long reach and high power budget links (>50 dB)