The possibility to characterize infinite and periodic frequency-selective surfaces (FSS) filters that have two orthogonal axes of symmetry inside a waveguide is reported. Thus, preliminary measurements can rapidly be obtained at low cost with few elementary cells instead of using a large FSS panel in free space. This is possible because of the equivalence that exists between the electromagnetic fields of two symmetric and oblique plane waves incident on and reflected from an infinite periodic surface and the incident/reflected fields that exist inside a single-mode rectangular waveguide containing a finite number of elementary cells. Comparisons of the measurements with some full-wave simulations for FSS belonging to the first three groups as they were defined by Munk confirm the good agreement between them. This is an interesting and simple assessment tool concerning the fabrication quality of FSS. The extension of this technique to non-symmetric FSS patterns is also discussed and supported by experimental and simulation results. The limitations of the technique are finally discussed.

Two new designs of the L-shaped Planar Inverted–F Antenna (PIFA) antennas with single and dual polarization operating at the frequency band for IEEE 802.11b/g standard with satisfactory radiation characteristics are presented. We further propose a genetic algorithm (GA) embedded in CST Microwave Studio for optimizing these antenna parameters. The agreement of simulation and measurement results shows the performance of our joint model. Also, they show that our dual-polarization antenna is suitable for indoor Multiple Input Multiple Output (MIMO) wireless environment applications.

This paper presents two feeding techniques for the radiation characterization of integrated antennas at millimeter-wave frequencies. The first method involves feeding the antenna-under-test (AUT) with a radiofrequency (RF) probe. We compare the measurements obtained with a standard RF probe, an extended probe, and an extended probe with reversed connector orientation. We find that the reversed orientation probe produces the best results in terms of effective measurement angular sector and reduction of ripples due to diffraction. The second method involves feeding the AUT through a flexible transmission line. This method achieves a larger range of measurement angles, but still suffers from parasitic scattering likely due to the mounting bracket and still need further development.

This paper synthesizes protocol measurements for Ultra High Frequency (UHF) radiofrequency identification (RFID) tags’ performance. We introduce the main parameters allowing the evaluation of an inlay tag performances. We characterize all devices implemented on the test bench. We explain the different programs and all methods used for the software automation. Finally, we studied the variation of the measured parameters as a function of power, frequency, or tag orientation, both in free space and in disturbed environment through our automated test bench