Monolithically Integrated Dual-Output DEML for Full Duplex DPSK-ASK and DPSK-SSB ONU in Ultra-Dense Channel Spaced Access Network

Coherent ONU based on 850 μm-long cavity-RSOA for next-generation ultra-dense access network

“…The rapid growth in global telecommunications and in particular, optical fiber communications, has continued to fuel the deployment of fiber access networks that are located closer and closer to the end users [1][2][3] . Unfortunately, the cost and footprint of the existing access networks are still vital factors to be considered [1][2][3][4] . The optical filter at the optical distribution network (ODN) is a large cost consumer for the whole optical fiber network; monolithic integration on the InP is a way to lower the footprint and to facilitate the design of complex photonic circuits with multiple functions [4] .…”

“…Unfortunately, the cost and footprint of the existing access networks are still vital factors to be considered [1][2][3][4] . The optical filter at the optical distribution network (ODN) is a large cost consumer for the whole optical fiber network; monolithic integration on the InP is a way to lower the footprint and to facilitate the design of complex photonic circuits with multiple functions [4] . Recently, an integrated semiconductor optical amplifier (SOA) and reflective-SOA (RSOA) have become available for wavelength division-multiplexed passive optical networks (WDM-PONs), reaching 10 Gb/s or more by means of wavelength reusing [5,6] and seeding techniques [7] .…”

“…Hence, the stability is dependent on the wavelength drifts of both of the lasers. It is desired that the laser number can be reduced to use only one laser at the ONU in order to reduce the complexity and spectrum overlap [4] .…”

“…The transmitter source is a DFB whose wavelength is influenced by the temperature controller, and as for the LO, we compare the DFB and ECL. For proper heterodyne detection, the two wavelengths should be precisely matched [4] . We investigate the BER penalty caused by the mismatch around the nominal intermediate frequency ( respectively (Fig.…”