Stubs‐integrated‐microstrip antenna design for wide coverage of circularly polarised radiation

Abstract

A generalised stubs-integrated-microstrip (SIM) antenna with wide coverage circularly polarised (CP) radiation is proposed for radio-frequency energy harvesting applications. The antenna consists of a microstrip patch radiator with four integrated asymmetric/symmetric-stubs and a coaxial feed. Four stubs are integrated at the corners of a square microstrip radiator. The stub lengths or stub gaps from the microstrip radiator are optimised for wide-beam CP radiation. Four different combinations of asymmetric/symmetric based SIM antennas are designed, fabricated, and tested. The proposed antennas are able to cover upper-half area with CP radiation across the 3-dB axial ratio bandwidth.

Microwave antennas—An intrinsic part of RF energy harvesting systems: A contingent study about its design methodologies and state‐of‐art technologies in current scenario

“…Prior to it, complete illustration about the microwave antennas in RF energy harvesting are presented with complete design perspective. A comparative study along with performatory analysis of microwave antennas are presented in Table ; keeping intact with rectenna characteristics: operating frequency, realized gain, polarization diversity, input power levels, and RF‐to‐DC power conversion efficiency, which was not in the scope of review papers for RF energy harvesting available in the open literature. Technically, to pursue clear understanding about tradeoffs of modern RF systems; five different cases of planar antennas (monopole antennas) at different bands with reflector surfaces and integrated with rectifier circuits are designed, simulated and analyzed by using FDTD domain solver (CST microwave studio) and circuit solver (advanced design system).…”

“…The relevant theories of basic forms of antennas are available in open literature . It is further classified into high performance antennas, metamaterial antennas, CP antennas, reconfigurable antennas, and array antennas . It is a strong belief that prerequisites need to be cleared before using the implicit technique in proposed antenna models.…”

“…[107][108][109] The relevant theories of basic forms of antennas are available in open literature. 36,65,70,75,80,85,91,96,101,104,107 It is further classified into high performance antennas, [110][111][112][113]159 metamaterial antennas, [114][115][116][117][160][161][162] CP antennas, [118][119][120][121][122][123][124][125][126][127][164][165][166][167][168][169][170][171][172][173][174][175][176][177] reconfigurable antennas,…”

A Novel Wideband Circularly Polarized Antenna for RF Energy Harvesting in Wireless Sensor Nodes

“…Circularly polarized antennas can be achieved using single-feed or multiple-feed structures. Several antennas for RF energy harvesting have been reported in [10][11][12][13][14][15]. A multilayer patch antenna with CP performance is presented for energy harvesting application in [10].…”

“…This antenna has wide-angle CP radiation of 140 o with a bandwidth of 3.2% and a gain of more than 5.0 dBic at 2.38 GHz. Four stubs are integrated at four corn of a square patch antenna to have CP performance in [12]. A maximum 10 dB bandwidth of 4.8% at 2.5 GHz is obtained for the asymmetric gap case.…”