Co-Existence of SiPh Sensing Link and Real World Traffic Over 100 m FSO Link for 6G Deployments

We propose two configurations for the coexistence of sensing and communication signals, exploiting Free Space Optical (FSO) links to transmit commercial 6G traffic and remotely interrogate sensors distributed along distances of 100 m. The sensors are fabricated on a Silicon Photonics (SiPh) platform, to achieve miniaturization and highly compact form of the required features. The first scheme consists of couplers and circulators, while the second utilizes polarization handling elements to multiplex both signals, while a 100-m outdoor Free Space Optical link is utilized for both schemes. The configurations exhibit high stability, with uninterrupted transmission of traffic along the duration of the experiments, while the sensors’ performance is evaluated, with their discrepancies measured below 2%.