Design Approach to Dual-Band Microstrip Patch Antenna with the Third-order Mode Suppressed

A dual-band asymmetric circular sector patch antenna is proposed. A coaxial probe is fed at the node of the third order resonant mode, such that the first- and fifth-order modes simultaneously excited while with the third-order one suppressed. In this manner, a dual-band antenna is realized. The impedance bandwidths of the antenna are 7.1% (2.69 ∼ 2.86 GHz) and 8.3% (4.13 ∼ 4.33 GHz) at low and high bands, respectively, and the dual-band ratio can be tuned from 1.46 to 1.78.