Front-end design for Ka band mm-Wave radar

Abstract

In this paper front-end design for a Ka band milimeter wave (MMW) radar which consists of an antenna, a low noise amplifier (LNA) and a band pass filter is presented. The operation frequency of the designed system is between 24–25 GHz in Ka band. A high gain axially displaced elliptical (ADE) dual reflector antenna is employed on the antenna structure. ADE sub-reflector with 5 cm diameter is illuminated by a feeder horn and a main reflector 30 cm diameter parabola focuses incoming waves from the ADE sub-reflector. According to the simulation results narrow half power beam width (HPBW=30) and high gain (G=35 dBi) are obtained with good efficiency (%58). An HJ-FET that has low noise figure (NF13 dB) is utilized to design a LNA. Double transistors are connected as cascaded to achieve higher transducer gain (Gt>19 dB). Matching circuits and feeder resonators are designed by microstrip lines to obtain low input and output VSWR (Vin