FINAL PROGRESS REPORT

/2. Technical Objectives: The principal objective of this project is to determine the most efficient means of encoding a microwave/millimeter wave signal from a patch antenna onto an optical carrier in an electrooptical substrate for subsequent optical processing of the microwave/millimeter wave signal. 3. Approac: . . Our approach was to develop design models that would relate the performance of integrated electro-optic devices to the fabrication parameters used in making them and then experimentall) verify their performance. Where lack of agreement was observed, the models were rethought and modified to improve their predictive behavior. Such performance characteristics included modal field distributions, propagation constants, coupling coefficients of channel waveguides and coupling lengths of proton exchanged directional couplers. This information was then used to design patch antennas and integrated optical modulators using various fabrication techniques and substrates. Similar design methods were used to determine the depth of modulation of electrooptic modulators. 4. Accomplishments: In order to achieve optically-controlled integrated millimeter-wave receiving phase arrays, single sideband modulation of an optical carrier by an incoming millimeter wave must be performed. Our research in this area began with the investigation of traveling wave structures used to obtain 90 degree phase shifts in millimeter wave signals. These structures consisted of slots in microstrip O - lines and were analyzed using a numerical (moment method) program. A theoretical model describing the interaction of a millimeter or microwave signal with an optical carrier was developed and used to determine the optical depth of modulati, n. A strip dipole was fabricated onto one o arm of an integrated optical Mach Zender interferometer. Modeling and fabrication of electrooptic devices in LiNbOa was then initiated. This led to the