The regular oscillations in scan impedance (normalized by the infinite array values) that occur across a finite array are uniquely altered in two special cases based on computer simulations of finite-by-infinite arrays. First, dipoles with groundplane at broadside in the E-plane, exhibit a slow modulation of the usual oscillations; the period of the modulation varies with dipole radius. For all...

In this paper, we characterize the rotational dynamics and observe rotor-rotor interactions within a crystalline, three-dimensional array of dipolar molecular rotors. The rotating portion of each rotor molecule consists of a dipolar fluorine-substituted phenyl group. The phenyl rotors are connected by acetylene linkages to bulky triphenyl methyl groups which are held rigid in the crystal lattic...

We report the design and experiment of a novel Yagi-Uda dipole array fed by a MS-to-CPS transition. The Yagi-Uda array having one director on the same plane of the dielectric substrate as the driver element shows higher gain (9.1dB) than microstrip patch antennas and a much wider bandwidth (10.3%). The measured front-to-back ratio is about 15dB. This novel design should become an important alte...

An optimal design of a linear antenna array is presented. The antenna array is optimized using a particle swarm optimization based method in order to produce a radiation pattern that has the minimum possible side lobe level and the maximum possible gain at the desired direction. The method has been applied to collinear wire-dipole arrays and seems to be suitable for improving the radiation patt...

Abstract ⎯ In this paper a printed dipole antenna and three slot antennas are designed to operate at 10 GHz for use in radar systems. A parametric study of each antenna and comparison between their radiation properties including return loss, bandwidth, directivity, efficiency and radiation patterns for 6-element linear array are introduced. Slot antennas show wider bandwidth, less coupling and ...