Patent ID: 8094081

Claim:
A common aperture dual-band antenna for optimally transmitting and receiving microwave and optical energy for high data-rate communications, the dual-band antenna comprising: (A) a shared portion comprising a primary reflector configured for focusing and reflecting said microwave and optical energy; (B) an optical portion in a largely Cassegrain configuration comprising: (i) an optical transceiver configured for high data rate transmission and laser beam pointing, acquisition and tracking, the optical transceiver further comprising: a laser source, an optical detector, a tracking detector array and a beam-steerer; (ii) an optical beam interface positioned substantially at a vertex of said dual-band antenna to facilitate integration the dual-band antenna with said optical transceiver; (iii) a dichroic secondary reflector configured for optical reflection and RF transmission; (iv) a dichroic vertex window configured for optical transmission and RF reflection; (v) an optical baffle positioned substantially between the primary reflector and the secondary reflector configured for shielding unwanted stray optical wave energy; (vi) a divergent lens positioned substantially at the vertex of the primary reflector and configured for transferring a collimated beam to the secondary reflector and for transferring an converging beam from the secondary to a collimated beam behind the vertex of the primary reflector; (C) a microwave portion in a direct fed configuration comprising: a microwave feed assembly further comprising: (i) an RF feed horn located on a central axis of the apparatus to which all portions of said apparatus are co-aligned proximal to the focus of the primary reflector, said RF feed configured for optimally illuminating the primary reflector with microwave energy for transmission to a remote terminal and for receiving microwave energy from said remote terminal reflected from the primary reflector and focused to the RF feed horn; (ii) a circular polarizer interface for circularly polarizing RF energy transmitted from said RF feed horn to allow the arbitrary orientation of the terminal around its pointing vector while communicating with said remote terminal.