High-gain overlapped elliptical shape diversity antenna for multiband applications

A three element overlapped elliptical shape MIMO antenna is designed and fabricated for ‘ISM band’, ‘WLAN’, ‘C-band downlink’ and ‘Ku band’ operations. It uses a partial ground plane for antenna miniaturization. Each radiating element of antenna is excited by a simple line feeding technique. Total size of the fabricated diversity antenna is $40\ \mathbf{mm} \times 40$ mm. The fabricated prototype is tested using vector network analyzer. Measurement results are found in a good agreement with simulation results. Radiation patterns are stable over resonating frequency. The correlation-coefficient is near to zero over operating band. This configuration gives a mutual coupling less than −10 dB over operating band. High-gain of antenna is achieved by modifying a rhombus-shaped antenna as overlapped elliptical shape by increasing the effective area of radiating elements.