Design and characterization of cross bow tie antenna array for focal plane array in terahertz imaging

A novel broadband Terahertz antenna design covering 100-600 GHz is developed as imaging pixel of THz focal plane array. Proposed focal plane array consist of novel cross bow tie antenna on quartz substrate behind the quartz hyper hemispherical lens. FPA performance is studied at low and high frequencies to determine the pixel pitch and number of effective pixels. Off axis performance of FPA is studied carefully to form a densely packed FPA with uniform patterns to high resolution imaging system. Some geometric variations are also made to improve off axis pixel patterns and overcome the reflection losses from lens. Compact dimensions of proposed planar antenna is resulted in densely packed array as compared to conventional self complementary antennas which enables to improve better pixel resolution by resulting in high directivity. Uniformity of far field patterns is achieved by proper placement of adjacent pixels.