A frequency selective surface for spatial filtering in the standardized Ultra-Wide Band (UWB) frequency range is proposed. A very large stop-band of 1.75–15.44 GHz has been obtained, with good polarization insensitivity and an angular stability of more than 60∘ and more than 50∘ in TE and TM incidence, respectively. Circuit models have been devised. The structure has been assessed by electromagnetic simulation and implemented on an FR4 substrate of 1.6 mm thickness, with an edge of the square-shaped unit cell of 15 mm. Tests in an anechoic chamber demonstrated good matching between simulation and experimental results and proper operation of the device.

No abstract

A single metal layer, multifunctional frequency selective surface with a very simple pattern of the unit cell, containing a U-shaped metal resonator on FR4 substrate, and working in the low GHz frequency range is proposed. The structure realizes dual linear polarization filtering at frequencies of 1.83 and 4.14 GHz with fractional bandwidths of 34.15% and 22.51% respectively, and linear-to-circular polarization conversion at 2.68 GHz, with 3.2 dB insertion loss (IL), 30-45 • angular stability depending on the direction of arrival of the incident wave, and 22.01% axial ratio bandwidth. The dimension of the unit cell corresponds to 0.09, 0.13 and 0.21 fractions of wavelength at the three operational frequencies. The functionality of the proposed structure is assessed by simulation, circuital model, and experiment in anechoic chamber. Scalability is demonstrated by designs that work at different frequencies, tested by simulation.

No abstract

Abstract-The paper describes a new real-time computation method named Mixt Profile of Speed (MPS), which is used to obtain the value of speed, at every sampling period of time, during the acceleration and deceleration stage, whereas the motion has three stages: 1) acceleration, 2) motion with imposed constant speed, and 3) deceleration. The method will determinate the location of a robotic arm for every sampling period of time. The originality of this new computation method refers to the deceleration stage; it determines an accurate positioning at the end of the motion in a well determinate interval of time. During the forced constant motion stage, the trajectory is imposed and it is linear or circular. The ADNIA algorithm (numerical differential analysis interpolation algorithm) can be implemented at this stage (during the motion with imposed constant speed of the robotic arm) in order to ensure the maximum precision of the computation for the waypoints Cartesian coordinates.