Leaky Coaxial Cable for Near-field UHF RFID Applications

In this paper, a leaky coaxial cable (LCX) used as reader antenna for applications in an ultra-high-frequency (UHF) radio frequency identification (RFID) system is proposed and investigated. As the LCX has the satisfied flexibility in placement for RFID application, the directional interrogation area can be well controlled. By designing the specific slot structures of LCX, the leaky radiating power of LCX can be increased significantly so that it can activate the passive RFID tag within a certain range perpendicular to LCX. The influences of some slot structure parameters on the LCX performance are studied and simulated. For demonstration, a prototype is developed and fabricated. The experimental results show that this LCX reader antenna can generate radio wave coverage in a narrow and long interrogation area, which is very promising to replace conventional directional antenna for UHF RFID applications in some special circumstances.