초록 ▼

Circularly-polarized antennas and their methods of use for active holographic imaging through barriers. The antennas are dielectrically loaded to optimally match the dielectric constant of the barrier through which images are to be produced. The dielectric loading helps to remove barrier-front surfa

Circularly-polarized antennas and their methods of use for active holographic imaging through barriers. The antennas are dielectrically loaded to optimally match the dielectric constant of the barrier through which images are to be produced. The dielectric loading helps to remove barrier-front surface reflections and to couple electromagnetic energy into the barrier.

대표청구항 ▼

We claim: 1. A circularly-polarized antenna connected to an active holographic imaging device and to at least one of a transceiver that transmits and receives, or to at least one transmitter that transmits and to at least one receiver that receives, electromagnetic radiation at one or more frequenci

We claim: 1. A circularly-polarized antenna connected to an active holographic imaging device and to at least one of a transceiver that transmits and receives, or to at least one transmitter that transmits and to at least one receiver that receives, electromagnetic radiation at one or more frequencies between 50 MHz and 1 THz through a barrier having a dielectric constant, the antenna characterized by:a dielectric loading comprising a dielectric material on which is fabricated antenna arms arranged as concentric Archimedean spirals originating at an antenna launch point, wherein the dielectric material has a dielectric constant substantially matching the dielectric constant of the barrier; anda balun that matches an unbalanced feed impedance to an impedance of the antenna launch point;