A compact printed 9-shaped dual-band monopole antenna for WLAN and RFID applications

Design of a simple compact printed microstrip fed 9-shaped monopole antenna for the WLAN and radio frequency identification (RFID) applications is presented. The antenna has the radiating element (having a 9-shaped structure), which supports resonances with large bandwidths for dual band RFID and WLAN applications. Effectively omnidirectional radiation pattern and large impedance bandwidth has been observed. Impedance bandwidth for -10 dB return loss around the 2595 MHz and 5180 MHz center frequencies reaches 639 MHz (2316 MHz to 2955 MHz) and 2372 MHz (3928 MHz to 6300 MHz) respectively.