This communication deals with simultaneous generation of a contoured and a pencil beam from a single shaped reflector with two feeds. A novel concept of generating a high gain pencil beam from a shaped reflector is presented using focal plane conjugate field matching method. The contoured beam is generated from the shaped reflector by introducing deformations in a parabolic reflector surface. This communication proposes a simple method to counteract the effects of shaping and generate an additional high gain pencil beam from the shaped reflector. This is achieved by using a single feed which is axially and laterally displaced from the focal point. The proposed method is successfully applied to generate an Indian main land coverage contoured beam and a high gain pencil beam over Andaman Islands. The contoured beam with peak gain of 33.05 dBi and the pencil beam with 43.8 dBi peak gain is generated using the single shaped reflector and two feeds. This technique saves mass and volume otherwise would have required for feed cluster to compensate for the surface distortion.Index Terms-Conjugate field matching, contoured beam, pencil beam, reflector surface distortion compensation, shaped reflector.

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There is a critical need for high bandwidth, high availability free-space optical communication links between the battlefield and the global information grid. Compact large aperture transceivers with low size, weight and power (SWaP) are needed to initiate and maintain communication links involving airborne platforms. The transceiver optical beam director typically contains fine and coarse steering stages. Existing beam director technology is based on electromechanical gimbaled mirrors with large SWaP that hinders deployment on many airborne platforms. To address the need for compact beam directors, we designed, fabricated, and tested an optical phased array (OPA) based on electrooptic dual frequency liquid crystal technology. This OPA has a transmissive architecture that enables a lower system SWaP, as compared to conventional reflective OPA. It has an 8 µm pixel pitch and steers over a 2.5° field of regard in one dimension at 1.55 µm. Two such OPAs can be stacked to steer in two dimensions. It has four independently addressable 1 cm x 4 cm regions arranged in a linear array to produce a continuous 4 cm x 4 cm aperture. The device incorporates novel addressing schemes to reduce the number of control channels by over an order of magnitude compared to conventional OPA addressing methods. It also utilizes proprietary low-loss transparent conductive Transcon TM film for low optical absorption in the infrared. The OPA uses a custom multi-channel controller circuit operating at a 500 Hz frame rate. We present results on OPA design, fabrication, and optical performance on steering.