Disk-loaded monopoles with parallel strip elements

Design considerations and experimental performance data are presented for disk-loaded folded monopoles in which the vertical elements consist of flat parallel strips separated by a dielectric. The presence of the dielectric and the flat strip geometry permit control of resonance frequency, susceptance slope, and impedance step-up ratio over ranges suitable for the design of electrically small antennas with a broad double-tuned response. Graphs are presented giving the impedance step-up ratio due to folding for various strip dimensions derived from static calculations. Experimental results are shown for antennas with heights in the range of one-eighth to one-tenth wavelength.