Development of microwave imaging reflectometer with tapered slot antenna array

Summary form only given, as follows. The purpose of this research is to develop a microwave imaging reflectometer by use of a tapered slot antenna(TSA) array on the focal plane. The tapered slot antenna has advantages such as a broad bandwidth, low cost and a compact, light-weight In addition, manufacturing of the array antenna is easy for its planer shape. A TAS have a nearly-symmetrical radiation pattern compared to that of a bowtie antenna TSA has good property of a high directivity. This antenna research has been active especially in the communication fields. We designed a LTSA(Linearly Tapered Slot Antenna) with corrugated structure for X-band. The corrugated structure improves radiation patterns of LTSA. The input impedance can be tuned over a wide range of frequency by adjusting the element dimensions, leading to a good matching condition without complex matching circuit. The impedance matching condition is calculated by an equivalent circuit model. By optimizing the strip-line dimensions, the bandwidth of 7-14GHz with VSRW<2 is obtained. The 3dB-beamwidth is 26 degree in the E-plane and 48 degree in the H-plane, respectively. In this paper, characteristics of the designed LTSA and mockup experiments of the reflectometer using a metal target instead of a plasma are reported.