Research, design and fabrication of 2.45 GHz microstrip patch antenna arrays for close-range wireless power transmission systems

Antennas play a very important role in wireless power transmission (WPT) systems using microwave since they affect the system transmission efficiency. General requirements for an antenna used for WPT systems are high directivity and narrow beamwidth. This paper presents the design, simulation and fabrication of microstrip patch antenna arrays for close-range WPT systems. Various antenna prototypes such as single patch, 2×2, 2×4, 4×8 and 8×8 microstrip patch antenna arrays working at 2.45 GHz are proposed. The 2×4 microstrip patch antenna array is fabricated and measured using Anritsu 37364D Vector Network Analyzer and NSI2000 Nearfield System. Measurement results show that the fabricated antenna obtains a directivity of 14.7 dBi and a 3 dB beamwidth of 23.2 degree. The experiment with the WPT system is carried out. This paper also presents structure of a WPT system and the role each building block in the system.