Investigations of a Load-Bearing Composite Electrically Small Egyptian Axe Dipole Antenna

Abstract

An electrically small, metamaterial-inspired Egyptian axe dipole (EAD) antenna has been investigated for use in structural composite materials. The EAD antenna consists of a differentially fed dipole element integrated with a near-field resonant parasitic EAD element. These elements have been adapted to these materials resulting in a system that is impedance matched and radiates efficiently at 307 MHz. Three cases have been identified and investigated to ascertain the performance of the manufacturing techniques and material properties used to build these electrically small antennas, as well as their performance characteristics. Uniquely, an embroidered conductive thread and a new carbon fiber based, nonwoven mat have been investigated for use as the conducting elements. Both cases are compared with a copper variant of the EAD antenna. All three prototypes were tested. Measurements confirm that both the nonwoven mat and the embroidered versions of the EAD antennas perform similarly with maximum realized gains ranging from 1.72 to 1.90 dBi.