Cylindrical Tightly Coupled Dipole Array Antenna

Abstract

A cylindrical tightly coupled dipole array antenna (C-TCDA) based on Munk’s planar TCDA theory, the elements of which are placed on the surface of a cylinder, is introduced and analyzed in this study. The explicit field components of the transverse electromagnetic (TEM) waves existing in the C-TCDA for both polarizations are given. Moreover, the embedding impedance characteristics of the C-TCDA are presented and compared with those of planar TCDA. Analysis results show that the C-TCDA has similar impedance characteristics to the planar TCDA and thus can be implemented in a similar manner. The design of a dual-polarized omnidirectional octagonal TCDA, which has a 3.08:1 bandwidth (from 0.73 GHz to 2.25 GHz) with a voltage standing wave radiation (VSWR) of less than 2 and a low gain variation of less than 1.8 dB at broadside for both polarizations, is also proposed. When scanning up to ±30° in the θ-direction, the array operates in the same frequency band with a VSWR of less than 2.05 and a low gain variation of less than 2 dB for both polarizations.

Keywords

• Array Antenna
• Omnidirectional Antenna
• Phased Array