On Synthesis of Orientation Insensitive Antennas

Abstract

Internet of things applications require orientation insensitive wireless devices to maintain stable and reliable communication. The devices developed can also require positioning or a special protocol communication as Global Positioning System, Bluetooth Low Energy or Wi-Fi, which all implement a specific polarization, namely right hand circular (RHCP) and linear (LP) for the last two. For those reasons, antennas providing near-isotropic radiation patterns along with wide far-field sphere polarization coverage, including LP and RHCP, are highly demanded in IoT applications. In this paper, we present some theoretical limitations on the synthesis of an antenna with near-isotropic radiation and polarization patterns. We consider two models: a set of orthogonal Hertzian electric dipoles located at different points, as well as a model of Hertzian magnetic dipoles located on faces of a perfectly electric conducting cube. These models allow synthesizing the near-isotropic radiation and polarization patterns of an antenna based on short dipoles, as well as a cubic antenna with radiating patches on the cube faces.

3D Antenna in Package Design: Maximizing Radiation Pattern Isotropicity and CP Coverage

“…The surface S1 is determined by S1 such that − #$% ≤ ( , ) ≤ . Similarly, the sum of the radiation pattern beam solid angles that satisfies axial ratio (AR) in the range of 1 ≤ ( , ) ≤ √2 [31,32] relative to closed spherical surface surrounding the antenna is a measure of the radiation pattern CP. A CP coverage factor is introduced as in a normalized integral form I CP , to estimate the CP pattern isotropy.…”

“…We have previously shown how to achieve near isotropic AoP design with the help of three orthogonally placed infinitesimal electric dipoles model [5]. Some preliminary work about achieving CP coverage has also been shown in [31,33]. In this work, we present the three printed electric dipoles model to achieve simultaneous near isotropy and wide CP coverage by finding the right phase conditions through PSO.…”

“…The radiation pattern of the Z oriented dipole has only a meridional component as in (5). (5) Where the phase error coming from the j-oriented dipole positions in spherical coordinates is expressed in [31] through spherical components as follows. We assume that the three orthogonal dipoles have equal moments and choose the moment in such a way to normalize the elevational and azimuthal components, i.e.…”