Real-Time 10 Gbps Polarization Independent Quasicoherent Receiver for NG-PON2 Access Networks

Abstract

In this paper, we propose and test experimentally a real-time 10 Gbps polarization independent quasicoherent receiver for NG-PON2 access networks. The proposed 10 Gbps quasicoherent receiver exhibits a sensitivity of-35.2 dBm after 40 km SSMF transmission with a commercial generic EML as transmitter. This sensitivity means a 14.9 dB improvement over a direct detection scheme with a photodiode after 40 km SSMF transmission. Therefore, the use of the proposed 10 Gbps quasicoherent receiver with the tested EML will provide a power budget of 35.64 dB (class E2) and a splitting ratio of 128 after the 40 km SSMF transmission. Finally, the proposed 10 Gbps quasicoherent receiver allows a colorless and optical filterless operation because wavelength selection is done by tuning the local oscillator wavelength and using electrical intermediate frequency filtering.

DSP-Free Real-Time 25 GBPS Quasicoherent Receiver With Electrical SSB Filtering for C-Band Links up to 40 km SSMF

“…The QC receiver [5,6] consists of an optical coupler combining the LO and the signal, followed by a polarization beam splitter (PBS). After the PBS, the signal and the LO of each polarization are detected with a PD and transimpedance amplifier (TIA) with a combined electrical bandwidth of 39 GHz.…”

“…A tuneable laser has been selected in the experiment reported here for the ease and repeatability of precise tuning. Previous studies [5,7] have demonstrated the QC receiver to be highly tolerant to laser line width and phase noise -real time operation with VCSEL transmitters and LO has even been shown. This is a consequence of the use of envelope detection which removes the phase information thereby increasing tolerance to phase noise.…”

DSP Enabled Optical Detection Techniques for PON

“…Alternative concepts were recently presented with real time implementation and refinements starting from the polarizationindependent receiver introduced by Glance Error [33], for either IM [5] or DPSK signals [12]. Using IM, the RX was successfully implemented till 10 Gb/s, by using analog electronic processing.…”

“…In addition, it was proven that the RX proposed in [5] also allows for VCSEL-based transmitters and LO: this feature makes it very promising for low-cost implementation.…”

“…Whilst coherent detection can allow for higher power budget and UDWDM operation, the use of expensive components and complex DSP can limit their deployment in PON [4]. Therefore, various solutions were proposed and demonstrated that achieve coherent detection by means of simplified processing, often analog processing [5]- [12]. The key benefit of this approach relies on the simplified operation, lower power consumption and higher cost effectiveness (analog processing is often combined with common COTS components).…”