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Broad Band Rectenna Based on Antipodal Vivaldi Antenna and NULT Rectifier

In this research paper, we study the performance of an innovative broad band rectenna that has been designed based on the combination of an antipodal Vivaldi broad band antenna and an efficient NULT RF-DC rectifier. The antenna have showed a directive pattern and an ultra-wide bandwidth of 1.66 GHz stating from 0.8GHz to 2.45GHz. The realized rectenna can harvest the ambient power of 4 major used frequency bands (0.8, 1.8, 2.1 and 2.45 GHz). The realized antenna is followed by a NULT impedance matching and rectifier in which the use of SMS 7630 Schottky diodes was essential to transform the harvested radiofrequency power into a useful DC power. The NULT prototype has shown an acceptable harvesting efficiency results at 3 of our frequency bands of interest. Due to the lack of access to professional test equipment caused by the major lockdown by COVID-19, the rectenna prototype was tested in uncontrolled environment and it was able to harvest 0.9 V at the distance of 3 m from 4 cell phones during communications.