Reconfigurable reflectarray antenna for microwave detection and imaging

This paper presents a design of a reconfigurable reflectarray antenna. A reconfigurable unit cell element based on varactor diode is first designed, fabricated and tested at X-band. Measured reflection phase range equal to 305° is obtained by tuning the diode biasing voltage. A reconfigurable reflectarray antenna of 10 × 10 elements is designed based on the proposed unit cell element. A prototype of the reflectarray antenna is fabricated and tested to validate the ability of pattern control. This reflectarray is used in a prototype compressive sensing detection system to detect threat objects in shoes.