Finisar (Germany)

Novel compact fully-hermetic E-band (71-86 GHz) coherent photonic mixer (CPX), featuring a rectangular waveguide WR12 output and providing an RF output power up to +15 dBm, is reported in this work. According to our knowledge, this is the highest reported output power level radiated directly from a photonic mixer module in the E-band frequency range. The fabricated WR12-CPX allows direct optical-to-wireless conversion of optical baseband or IF-band signals, e.g. for radio-over-fiber (RoF) fronthauling in mobile communications. The module comprises an InP-based balanced-PD (BPD) chip, a GaAs HEMT MMIC medium power amplifier, and a laminate-based grounded coplanar waveguide to rectangular waveguide (GCPW-WR12) transition. The transition couples the optically generated, e.g. via heterodyning, millimeter-wave signal from the output of the BPD chip to the WR12. It is based on a double-slot antenna structure and developed on a Rogers RT/duroid 5880 laminate with a thickness of 127 µm. The presented GCPW-WR12 transition enables the development of fully-hermetic photonic packages, which is required to improve the durability of the BPD chip. The transition design is optimized by utilizing a 3D electromagnetic simulation software for achieving a wide operational bandwidth with an average insertion loss (IL) of about 1.6 dB and a return loss (RL) higher than 15 dB in the frequency range of 71-86 GHz. Finally, the RF responsivity of the WR12-CPX module and the hermeticity of the transition are experimentally characterized.

S.4598-4610

An overview of the advanced Indium Phosphide (InP) Electro-Optic Mach-Zehnder (MZ) Modulator technology which enables small form factor pluggable transceivers for coherent transmission is presented here. A highly efficient IQ-Modulator with a low insertion loss (IL), low Vπ, high extinction ratio and high electro-optic bandwidth is demonstrated. The modulator described here is very well suited for pluggable 100G/200G coherent transceivers with stringent electrical power consumption requirements. Additional functions already implemented on the mature InP photonic integration platform are expected to add further functionality to the InP IQ Modulator and finally result in a monolithic InP coherent transmitter.