A substrate for small patch antennas providing tunable miniaturization factors

Abstract

Abstract-Magnetic properties were imparted to a naturally nonmagnetic material by metallic inclusions. A patch antenna tested the performance of the magnetic metamaterial as a substrate and validated that a single substrate can achieve a range of miniaturization values. The effective medium metamaterial substrate employed electromagnetically small embedded circuits (ECs) to achieve permeability and permittivity greater than that of the host dielectric. Geometric control of the ECs allowed and to be tailored to the application. The magnetic metamaterial exhibited enhanced and with acceptable loss-factor levels. Models for predicting and are presented, the benefits of employing metamaterial substrates are discussed, and the results in this antenna experiment are presented. The metamaterial exhibits performance characteristics not achievable from natural materials. Of particular significance is that with the permeability varying strongly and predictably with frequency, the miniaturization factor may be selected by tuning the operating frequency.

`A Novel Design Algorithm' and Practical Realization of Rectangular Patch Antenna Loaded With SNG Metamaterial

“…Incident magnetic energy induces currents in the circuit loops and causes coupling of energy into the resonators. Eventually it changes the relative permeability of the medium in that direction [14]. In other directions, relative permeability experienced by other magnetic field components will be that of free space (µ 0 ).…”

Erratum: On the advantages of magnetic materials in microstrip antenna miniaturization

“…Due to a technical error of the authors, references [3,4] are missing in paper [1]. The three first sentences in the second paragraph of Introduction should read as follows.…”

“…Authors of [2,3,4] postulate that in the patch antenna geometry, the dominating energy storage mechanism is capacitive in the electric field. It is mentioned that the increase of l will lead to an increase in the magnetic energy storage [4], and this will weaken the magnetic-electric energy imbalance [3].…”

“…It is mentioned that the increase of l will lead to an increase in the magnetic energy storage [4], and this will weaken the magnetic-electric energy imbalance [3]. This is said to automatically widen the bandwidth [3,4].…”

Miniaturized negative permeability materials

“…5,15 In order to increase the distributed capacitance, cylindrical sheets are wound as coils, in which the structure is called a Swiss roll. 5,6 The flat version of the Swiss roll is called the spiral resonator, 10,16 which is commonly used as a lumped inductor in microwave engineering. 17 In addition to changing the geometry of the structures, one can introduce lumped elements to the existing structures.…”