Unthinkable, but in the field of photonics this has just been demonstrated by AIT Austrian Institute of Technology through calling a disruptive approach into question: why not using a transmitter as receiver?
The innovative work spearheaded by AIT researcher Bernhard Schrenk from the Center for Digital Safety & Security demonstrates the shoehorning of an entire coherent homodyne receiver in a simple and cost-effective laser-based modulator device that is typically used as widespread transmitter in a variety of telecom and datacom applications. Analogue operation without digital signal processing enables a truly lean solution that bears the cost credentials for short reach networks – a domain where direct photodetection currently prevails. The proposed and experimentally demonstrated solution has the potential to migrate from these direct-detection systems towards coherent ones – a process that has been undertaken in wireless communication decades ago as electronic integration had matured and became widely available. It now enables to pack communication channels in ultra-dense spectral allocations. In optical communication, complexity still prevents industries from doing so.
The team at AIT goes even a step further and pursues the challenging task of accommodating coherent receiver and transmitter functionality with the same photonic device, without adding extra componentry. This monolithic transceiver based on the same externally modulated laser enables the simultaneous bidirectional coherent transmission of digital or analogue signals, such as required for intra-datacenter, optical access or 5G fronthaul applications.
AIT’s proof-of-concept paper has found recognition by being top-ranked at OFC 2018, which with more than 15,000 attendees and ~1,000 contributed papers is the world’s leading global conference and exhibition for optical communications. More importantly, AIT’s contribution has been selected as finalist for the prestigious Tingye Li innovation price, which will be awarded by the Optical Society in March 2018.
Besides this cutting edge work, the AIT team with its focus on photonic technologies got 5 more papers accepted at this top-of-the-line congress, including topics such as LED-based LiFi, QKD pluggables for low-cost consumer applications, 5G radio transmission and novel optical data encoding schemes exploiting the 3D polarization space.