The Fraunhofer Heinrich-Hertz-Institut (HHI) is working on the further development of passive optical networks (PON) in the PONTROSA project to promote fiber optic expansion and explore new applications for the technology. The institute, together with project partners, will develop new electronic and optical subsystems to significantly increase the transmission capacity of future PONs. The project, funded by the Federal Ministry of Education and Research with 3.8 million euros, will run for three years until September 2027.

Passive optical networks (PON) have become prevalent over active optical networks (AON) for their cost-effectiveness and simplicity. However, to meet future demands and new application areas, such as connecting data centers and distributed mobile stations, the achievable data rates need to be significantly expanded.

The project team will design, fabricate, and integrate optimized electronic and photonic integrated circuits into a complete system. The researchers will also analyze the requirements for digital signal processing and develop appropriate methods.

➀ A UWB, 0 to L band, polarization-insensitive (PI) 1×12 100GHz channel spacing arrayed waveguide grating (AWG) was designed and implemented a 3µm insulator on silicon (SOI) platform by VTT, with insertion losses ranging from -0.82 dB to -1.52 dB.

➁ A 3µm thick silicon waveguide has ultra-low propagation loss (0.1 dB/cm) and low birefringence over a wide wavelength range (1.2µm to 4µm).

➂ A 40-channel 100GHz spacing (de-mux/mux) multiplexer based on cascaded PEG was designed and manufactured on a 3µm SOI platform, with low crosstalk and low insertion loss.