The combination of two higher order hybrid electromagnetic modes (HEM 133 and HEM 123 ) in a simple cylindrical dielectric resonator is exploited in the presented paper to enhance antenna gain. Both modes were excited by the same feeding aperture in the ground plane of a microstrip line. A linearly polarized, broadside radiation pattern with maximum realized gain of about 11.6 dBi was successfully obtained. The antenna was designed for the ISM band with central frequency 5.8 GHz and relative bandwidth at least 2.6 %. For fabrication, we used a layered Arlon AR600 substrate of relative permittivity 6.15. Experimental results showed reasonable agreement with simulations and validated the new concept of the high gain dielectric resonator antenna.Index Terms-Dielectric resonator antennas, directive antennas, higher order radiating modes.

This paper deals with suitable antennas for energy harvesting, which is a growing research field due to the utilization of nowadays ubiquitous and abundant RF energy. Four types of basic antenna structures suitable for harvesting applications, namely, the patch antenna, slot antenna, modified inverted F antenna, and dielectric resonator antenna, are compared from the viewpoint of reflection coefficient, efficiency, radiation patterns, and dimensions. The frequencies of interest were chosen so that they cover several main wireless systems operating between 0.8 GHz and 2.6 GHz, that is, GSM, UMTS, and WiFi.

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The study deals with the application of low‐temperature co‐fired ceramic (LTCC) technology for design of a higher‐order mode dielectric resonator antenna element operating at centre frequency 25.7 GHz. The LTCC material that the authors use provides very low dielectric losses and enables us to design an antenna element with very high radiation efficiency. The authors follow by examining the mutual coupling between two resonators and the authors propose a small (1 × 4) one‐dimensional antenna array composed of such elements. In order to minimise the dimensions of the ground plane and to place the connector at a convenient location, the authors design a parallel feed network in substrate integrated waveguide technology, thus reducing the radiation losses of the feeding structure. The experiments verify the four‐element antenna array concept with maximum measured gain of 16.3 dBi.

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