Title :
A multi unsymmetrical beam tapered slot-yagi antenna for PMMW imaging
Author :
Yu, Ya-Chung ; Huang, Chun-Yen ; Chang, Li-Yuan ; Nien, Chin-Chung ; Tarng, Jenn-Hwan
Author_Institution :
Identification & Security Technol. Center, Ind. Technol. Res. Inst. (ITRI), Hsinchu, Taiwan
Abstract :
A compact multi-unsymmetrical beam and high isolation antipodal linearly tapered slot-yagi antenna (TSYA) array with quarter-wave fan-rejections (QWFR) is proposed for feed antenna of lens in the near-field PMMW imaging applications. With changing QWFR structure, the different traveling current path provides the non-uniform phase field distribution for radiation aperture, which creates the function of multi unsymmetrical beamwidth to cover lens for each feed ALTSA at the focal plane, and these side lobe levels (SLL) of radiation patterns of ALTSA transformed by lens can be restrained to enhance the spatial resolution of the near-field imaging lens. Due to quarter-wave shorted circuit fan-rejections, they provide high isolation -30dB between ALTSA array for reducing pattern interference. The proposed ALTSA with QWFR covers 75~95GHz and 3 dB beamwidth is 70 degree for our lens of diameter of 20cm and focal length of 14cm.
Keywords :
Yagi antenna arrays; antenna radiation patterns; slot antenna arrays; PMMW imaging; compact multiunsymmetrical beam; focal plane; high isolation antipodal linearly tapered slot Yagi antenna array; near field imaging; nonuniform phase field distribution; quarter wave fan rejection; radiation aperture; radiation pattern; side lobe level; Antennas; Lenses; Fan rejection; LTSA; Multi-beam antenna;
Conference_Titel :
Electronics, Circuits, and Systems (ICECS), 2010 17th IEEE International Conference on
Conference_Location :
Athens
Print_ISBN :
978-1-4244-8155-2
DOI :
10.1109/ICECS.2010.5724737
