Chirp Management Tunable SFP+ Transceiver Based On AWG

The application of DWDM(Dense Wavelength Division Multiplexing)can well solve the shortage optical fiber resources in 5G fronthaul construction.The tunable transceiver is the technical basis of DWDM.The low-cost VCL(V-cavity laser)T-SFP+(Tunable Small Form-factor Pluggable plus)is ideally suited for cost-sensitive 5G fronthaul applications.But transmission distance of the direct modulation type VCL T-SFP+is limited.A low cost dispersion penalty solution is neededIn this thesis,we study the VCL chirp theory firstly.Then we propose AWG(Arrayed Waveguide Grating)-based chirp management to extend the transmission distance of VCL T-SFP+,and design a shared wavelocker based on AWG and low-speed carrer communication to maintain the chirp management effect.The principle of AWG-based chirp management is to use the AWG as a high-pass filter to filter and equalize optical signals to reduce ISI(Intersymbol Interference).We set up a test system to study the chirp management scheme:the equalization characteristics of AWG,the dispersion tolerance,and the difference of VCL channels Then we proposes to lock the edge slope of AWG to adapt to different bandwidth AW Gs,and to increase the chirp of short-wavelength channels so that each channel can achieve 20km error-free transmission with a power budget of 20dB.The shared wavelocker uses the edge of the AWG to perform frequency-to-power conversion,and feedbacks compensation through low-speed carrier communication to achieve wavelength locking.An experimental system was built to verify the feasibility of the shared wavelocker.In the ambient temperature range of-40?85 ?,the shared wavelocker can optimize the frequency drift from±3GHz to+1.3GHz?-1.9GHz.This thesis also discusses the thermal chirp of VCL:laser frequency shift caused by thermal effects at low speed modulation.The degradation of the thermal chirp low-speed carrier signal by the AWG filter is analyzed,and several solutions to the negative effects of the thermal chirp are proposed.