Resonant circular patch microstrip antenna with air gap
The resonant frequency and bandwidth characteristics of superstrate loaded air gap tuned circular patch microstrip antenna are investigated for different structural parameters. The problem is formulated in spectral domain and Galerkin's method is used for the solution. It is shown that adjustable air gap between the ground plane and substrate compensates superstrate loading effect on the resonant frequency, increases bandwidth and provides tunable operational characteristics.
Analysis of circular microstrip antennas with superstrate
The spectral domain analysis is applied to study the effects of dielectric cover on a circular microstrip patch antenna. Numerical examples indicate that the resonant frequency of the patch is decreased considerably while the bandwidth is varied slightly.
Reading research critically: assessing the validity and reliability of research instrumentation--Part 2.
Accurate measurement of research variables is necessary so that research consumers can trust that it is the research intervention that affected the change in the outcome variable, not some extraneous error component. Reliability is the accuracy with which the research instruments measure the variable that they are designed to measure. A number of known threats to instrument reliability should be anticipated by the researcher and looked for the consumer. These threats are presented in this article.