Chip Laser Combs for Free Space Optical Communication.

CRC Project Number: 1-06

Project Leader: Prof David Lancaster, UniSA

Participants: University of South Australia

A Chip-based frequency comb FSOC system as a basis for super channel architecture that can utilize coherent processing due to the fixed phase relationship between all comb laser lines.

Optical frequency combs (f-combs) are an emerging disruptive laser technology capable of replacing 10s to 100s of individual CW lasers to produce densely packed optical superchannel transmitters. For free-space optical communication (FSOC) applications, a more profound advantage over arrays of independent laser transmitters (ie. ‘dumb’ lasers), is that frequency combs have an intrinsic phase relationship between the channels which allows ‘pilot’ channels to be allocated that can be digitally and coherently processed at the receiver end. A further advantage of using a frequency-comb based transmitter is the potential for a signal processing mechanism to compensate for atmospheric distortion for all comb lines. This proposed architecture could in the future be evolved towards a completely smart and reconfigurable software driven transmitter.

Our proposed FSOC transmitter is a unique and stable chip laser frequency comb architecture that is at an early TRL for this application but has already been demonstrated to produce a world-leading stable frequency comb, and to date only been applied to spectroscopic applications.