Millimeter-wave Modulators for Sparse Imagers

In this Phase I SBIR effort we will develop advanced electro-optic (EO) sensing module that are capable of efficiently up-converting mmW signal into optical sidebands for passive millimeter wave imaging applications. Conversion efficiency of the modulators can be significantly enhanced by virtual of thin-film Lithium niobate on insulator (TFLNOI), RF resonator, and optical resonator, in which the TFLNOI leads to about 10×reduction in mode size and thereby tighter mode confinement in both optical and RF domains, RF resonator design in coplanar waveguide provides significant electric field concentration for large EO interaction, and high-Q optical resonator design offers additional fineness in EO modulation to further improve the sensitivity of the upconversion module. The improved modulation efficiency reduces gain requirement of the RF frontend, thereby significantly simplifying the RF packaging process. After device design and optimization, we will conduct preliminary fabrication of these advanced EO modulators and then implement the integration with the previously developed RF frontend channel to complete the upconversion module fabrication. Characterization will be performed to evaluate the modulator conversion efficiency and detection sensitivity. An array of the sensor nodes will be integrated into our eight-channel sparsely distributed aperture to validate the performance of EO modulators.