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With the significant rise of low power embedded devices in various applications of both consumer and commercial usage, the surge for continuous power requirements has initiated promising research toward alternative sources of energy. It includes the domain of wireless power transmission, internet‐of‐things, wireless sensor nodes, machine‐to‐machine, and radio frequency identification. Thus, the overall scope of this review article is to witness microwave antennas and its implementation in RF energy harvesting system through ambient RF signals. For this reason, unified understanding of classical electromagnetism is needed; beginning with the fundamentals of RF transmission and the exploration of concepts such as Fraunhofer's Distance and Friis Transmission Equation. It is followed up by the analogy of dependency of parameters like circuit build‐up, conversion efficiencies and amount of power harvested, which is quite crucial from the rectifier point‐of‐view. For better improvisement in RF energy harvesting systems, five different cases of monopole antennas are explored with reflector surfaces such as PEC (perfect electrical conductor) and AMC (artificial magnetic conductor) integrated with the rectifier circuit. Implementation with wide diversity has proposed a generalized solution for achieving tradeoffs: polarization and pattern diversity with consistent system efficiency; leads to clean and sustainable energy for low power‐embedded devices.

This article presents a chronological overview of circularly polarized dielectric resonator antennas (CPDRAs). This article provides a comprehensive review about innovation and rapid developments of CPDRAs over the last three and half decades since 1986s. The objective of this article is to highlight the basic concept of CP mechanism in DRA and state‐of‐the‐art developments of CPDRAs in terms of single and multi‐point feed for unmodified and modified DR geometries considering different types of excitation mechanism such as microstrip line, coaxial probe, and aperture coupled feed. To give insights into circular polarization, Authors proposed a compact modified CPDRA. It offers simulated bandwidth of 47.5% (2.34‐3.80 GHz), measured impedance bandwidth of 50.8% (2.26‐3.78), and simulated axial bandwidth of 13% (3.29‐3.75 GHz) respectively. Other antenna parameters such as peak realized gain and radiation efficiency are 7.7 dBi and 98% within operating frequency bands, respectively. The proposed outcomes confirm that the proposed CPDRA can be used as a suitable candidate for wireless body area network applications.

In this article, a broadband circularly polarized rectangular dielectric resonator antenna (CP‐RDRA) is explored and reported. The proposed antenna comprises of rectangular dielectric resonator (DR) made up of aluminum oxide placed on a Rogers RT‐5880 substrate and fed by a 50‐Ω microstrip line with a partial ground plane. Microstrip line feed is placed at the right edge of rectangular DR to excite orthogonal fields, which achieves circular polarization (CP). The proposed antenna is fabricated and characterized. The measured −10 dB impedance bandwidth and 3 dB axial bandwidth are obtained as 5.44 GHz (5.79‐11.23 GHz) and 2.93 GHz (6.08‐9.01 GHz), respectively. The peak realized gain and antenna efficiency are obtained to be 4.62 dBi and 94%, respectively, in the desired frequency band. In addition, the proposed CP‐RDRA is also realized using a new technique of glueless concept to achieve mechanical stability that also enhances the axial bandwidth without affecting the radiation characteristics. It is observed from the results that the proposed antenna can be a potential candidate for C‐band and X‐band in satellite communication systems.