Characteristic Mode Analysis of Wideband Patch Antenna Using Dual-Mode Resonance

This paper presents the characteristic mode analysis(CMA) of wideband patch antenna using dual-mode resonances. CMA is used to analyze the fundamental resonance modes of square patch antenna. It has two fundamental modes of TM01 and TM10 modes. The patch is excited using aperture coupling to excite both horizontal and vertical mode. The slot aperture length and width is optimized for better coupling. The vertical mode resonance frequency is slightly reduced by introducing the slot. These two modes combined together gives the wide bandwidth. An impedance bandwidth of 47.12%(1.93GHz-3.12GHz) is obtained. The antenna is well radiated with both modes being radiation efficiency of above 90%. The realized peak gain of 5.72dBi and 4.62dBi is obtained at 2.12GHz and 2.83GHz and good radiation pattern in the broadside direction. The cross polarization level of more than -10dB is achieved with respect to co-polarization level at resonance frequency of 2.12GHz and 2.83GHz respectively and it is suitable for WiFi and Bluetooth applications.