An Integrated Photonic and RF Transmitter for Phased Arrays

"An integrated circuit is proposed which combines coplanar transmission lines, optical waveguides, high power transistors and high power lasers monolithically. The aperture for an RF radar element should be designed as a transmission line with itscharacteristic impedance matched to that of free space. We propose to achieve this with a field-effect structure in which gate and source terminals form a coplanar line. The input is introduced as a gate-source signal at one end and propagates to the freespace termination at the chip edge. It is also possible for the field-effect device to operate as a laser in which the channel region between the sources acts as the waveguide for a high efficiency laser. With the laser biased above threshold, an opticalwaveguide terminates at the chip edge, such that the modulation power impressed upon the optical signal at the waveguide input is launched as the optical output of a LADAR element. Thus the optical and the RF energies emerge from a common output port(common pointing accuracy) with matched traveling optical and RF wave velocities, eliminating the need for separate chips. In this SBIR, we will develop the technology platform to realize common aperture EO and RF transmitters. The EO/RF common aperturetransmistters will become the basis for compact sources for aircraft and auto communication and radar systems. In addition, the ability to produce integrated electronic and optical functions will fo