Testing and Analysis of MOSFET-Based Absorber Integrated Antenna for 5G/WiMAX/WLAN Applications

A 3D electromagnetic circuit design and analysis of a MOSFET-based absorber active integrated antenna has been performed. It integrates a transmitting dual-band double material substrate (DMS) cylindrical surrounding patch antenna (CSPA) with a MOSFET-based absorber of reflected radio frequency power. It is a solution to the problem of performance degradation in the power amplifier (PA) resulting from antenna and PA impedance mismatch. This fully integrated MOSFET-based absorber antenna can absorb reflected RF power with a diode-based quasi-circulator as part of the integrated design circuitry. The antenna used for the proposed integrated design will operate at frequencies ranging from 2 GHz to 3 GHz and from 4.6 GHz to 6.1 GHz, thus providing a bandwidth of 1 GHz and 1.5 GHz at a resonance frequency of 2.5 GHz and 5.3 GHz, respectively. This makes it suitable for use in lower and upper bands of WLAN/WiMAX medium RF front-end applications. Furthermore, the condition for MOSFET connected to the absorber (I_S ≤ I_D and V_DS = 0) has been satisfied at both instances of resonance. In this proposed design, an antenna radiation efficiency of 84% has been observed.