A planar monopole antenna integrated with delay line for passive UWB-RFID tag applications

A planar monopole antenna and a simple delay line are simulated, fabricated, and measured in this paper. The designed antenna is with quasi-omnidirectional radiation pattern and 10 dB impedance bandwidth of 3.08 to 10.02 GHz. The developed delay line works in the lower UWB band (3.1 - 4.8 GHz) with loss of 2.78 dB and two-way time delay of 3.50 ns. These two components are further integrated for the passive tag applications of UWB-RFID location system.