An analytical theory has been developed for finding out the modal characteristics of a solid dielectric pyramidal horn. The dispersion characteristics have been solved numerically by varying various parameters, such as, axial length, flare angle and relative dielectric constant of the horn to investigate the modal characteristics which is crucial to include or avoid higher order modes in dielectric horn antenna design.

Propagation Characteristics of Guided Modes in a Solid Dielectric Pyramidal Horn

By flaring a dielectric waveguide in the H-plane, an H-plane dielectric horn is formed, which could be directly excited by an SIW feed. However, matching and radiation performances are poor due to the thinness of the substrate. To improve these performances, some periodic parallel strips are printed both on the top and bottom planes of the dielectric horn. These strips guide and leak the electromagnetic waves gradually along the horn, finally enhancing the end-fire radiation both in H-plane and E-plane. Moreover, they increase the impedance bandwidth up to 38% in Ka-band, and improve the realised gain by around 2 dB. Indeed, a gain of 14.3 dBi is achieved at the centre frequency, with a front-to-back ratio of 27 dB, a side-lobe level of −22 dB in the H-plane, and the narrowed E-plane and H-plane half-power beamwidth of about 20°. The measured and simulated results agree with each other very well. In addition, the proposed H-plane horn antenna is very compact, low cost, and could be easily integrated.

https://ietresearch.onlinelibrary.wiley.com/doi/pdf/10.1049/iet-map.2016.0850

Wideband H-plane dielectric horn antenna

The theoretical and experimental Investigation of the aperture field (amplitude only) of E-Plane Sectoral Hollow Dielectric Horn Antenna has been made. The metallic walls of the metal horn is replaced by dielectric sheets (perspex) to obtain such type of antennas. As these antennas have complex boundary nature, several simplifying assumptions have been made to solve the problem. A comparison has been made between theoretically calculated and experimentally observed values.

E-Plane Sectoral Hollow Dielectric Horn Antenna

Aperture/near field distributions of solid dielectric diagonal horn antennas have been studied, both theoretically and experimentally. Solution of the Helmholtz equation is obtained for TE to x and TE to y modes using separation of variables technique for the horn. Transcendental equations for the transverse components of the propagation constants are obtained by applying proper boundary conditions, i.e. the continuity of the electric and magnetic fields at the dielectric-air boundaries. These transcendental equations are solved for the transverse propagation constants for the fundamental mode for three horns each 1 of axial length = 12.8 cm and flare angle = 8.5° and with dielectric constants e 1 of the materials of the horns equal to 2.54, 2.56 and 2.80 at the frequency 9.418 GHz in the-band X-band. The theoretical aperture field distributions obtained for Hx 11 and Hy 11 modes propagating in these antennas are compared with corresponding

Near field distribution of solid dielectric diagonal horn antennas

Far field patterns of solid dielectric diagonal horn antennas of various dielectric constants (e 1 = 2.54, 2.56 and 2.80) are studied theoretically and experimentally at 9.418 GHz. Theoretical near field distributions at the aperture and at the four side surfaces of a horn under study for TE x to and TE y to modes are obtained by solving Helmholtz's equation using the separation of variables technique. The expressions for the near field components of the horn under study are used to obtain the expression for radiation pattern from Kirchoff's diffraction formula. The theoretical far field patterns obtained for these antennas are compared with the corresponding experimental ones.

Far field patterns of solid dielectric diagonal horn antennas

The present paper deals with the H-Plane Sectoral Solid Dielectric Horn Antenna. Attempts have been made to determine theoretically the approximate surface fields (Ampli tude and Phase) under several simplifying assumptions. A comparison has been made between calculated and experimentally observed values of one of the field components for both amplitude and phase at the front aperture of the antenna. A fairly good agreement has been obtained between them.

R.K. Jha

Papers

Surface Fields of the H-Plane Sectoral Dielectric Horn Antenna