Defected Ground Structure of UWB Chipless RFID Tag for FMCW Radar

In this paper, a radio frequency identification (RFID) reader architecture composed of two signal generators, a mixer, an amplifier, and a low-pass filter (LPF) for reading a 2-bit chipless RFID tag is proposed. This tag consists of integrated microstrip and defected ground structure (DGS) with U-slot resonator to realize compact 2-bit design, and these slotline resonators can provide transmission zeros. The reader is a frequency modulated continuous wave (FMCW) radar, which interrogates a tag and decodes the tag’s identification data.