Silicon Photonics Enabled Hyper-Wideband RF Receiver With >85% Instantaneous Bandwidth

We demonstrate the first-ever silicon photonics enabled hyper-wideband RF spread-spectrum link. A hybrid III/V-silicon photonic mode-locked laser encoded with a four-channel silicon photonic phase encoder is used to generate optical carriers that coherently demodulate a received RF signal spanning an instantaneous bandwidth greater than 85% of the center frequency (12/14 GHz). This allows low-speed (<;3 GHz) electronics to be used in place of the traditional costly and high-power wide-bandwidth electronics used in an all-electronic hyper-wideband link. In addition, integrated highly tunable optical notch filters are successfully used to reject unwanted narrowband interference, with rejection ratio and tunability that surpass conventional wireless technology.

I. Introduction

Integrated photonics promises to bring the advantages of optics, particularly large bandwidths and wide-band tunability, to the aid of domains traditionally served by bulky electronics. Common difficulties with bulk and fiber optics such as lack of phase stability and expensive and laborious alignment prevent large-scale highly complex systems to be built in a low-cost and mechanically stable way. By overcoming these challenges, integrated photonics opens up new possibilities for optics and leads to new applications of light beyond merely shrinking existing optical systems to smaller sizes. One such application is in the realm of hyper-wideband wireless communication.