Photonic integrated circuit technologies for RF photonic links

A radar frontend transports and frequency down converts antenna signals. Traditional electronic frontends are built on transistors and diodes. But these transistors and diodes are sensitive to electromagnetic interferences and very nonlinear resulting in limited system spurious free dynamic range (SFDR). Thus, it is desirable to replace the electronics with high dynamic range RF photonic links.In this work, we investigate photonic integrated circuit technologies for high dynamic range integrated RF photonic frontends. We proposed the concept of integrated RF/photonic radar frontends, where an entire RF photonic link is monolithically integrated on a photonic integrate circuit (PIC). The integrated RF photonic link employs optical phase modulation and linear phase demodulation by an attenuation counter propagating optical phase locked loop (ACP-OPLL). The link achieves frequency down-conversion either by exploiting nonlinear phase modulation inside quantum well phase modulators or by optical sampling. It has the potential to outperform electronics. In addition, photonic integration provides the benefits of having a small size and high power efficiency, and being lightweight and low cost.