Title :
Analysis and design of two-arm conical spiral antennas
Author :
Hertel, Thorsten W. ; Smith, Glenn S.
Author_Institution :
Sch. of Electr. & Comput. Eng., Georgia Inst. of Technol., Atlanta, GA, USA
fDate :
2/1/2002 12:00:00 AM
Abstract :
The two-arm, conical spiral antenna is analyzed using the finite-difference time-domain method. The analysis is validated by comparison with measurements of the input impedance and the realized gain. A parametric study is performed with the analysis, and the results from the study are used to produce new design graphs for this antenna. These graphs supplement and extend the existing, mainly empirical, design base for this antenna. Two resistive terminations, intended to improve the low-frequency performance, are examined. One is a termination formed from two lumped resistors, and the other is a new termination formed from a thin disc of resistive material. These terminations are shown to improve the front-to-back ratio and axial ratio for the antenna
Keywords :
UHF antennas; antenna radiation patterns; conical antennas; electric impedance; finite difference time-domain analysis; spiral antennas; FDTD; axial ratio; broadband antenna; design graphs; finite-difference time-domain method; front-to-back ratio; gain; input impedance; low-frequency performance; lumped resistors; parametric study; resistive material; resistive terminations; two-arm conical spiral antennas; Antenna measurements; Arm; Broadband antennas; Dipole antennas; Finite difference methods; Frequency; Magnetic field measurement; Resistors; Spirals; Time domain analysis;
Journal_Title :
Electromagnetic Compatibility, IEEE Transactions on
