Planar/folded 2-arm trapezoidal LPDA

Image of the Planar/folded 2-arm trapezoidal LPDA.

Log-periodic antennas provide structures whose electrical properties vary periodically with the logarithm of frequency. The result is impedance and radiation characteristics that repeat periodically with frequency and have minimal variation over a wide band.

The planar/folded 2-arm trapezoidal log periodic antenna is similar to the rounded planar log-periodic antenna already available in Antenna Magus, but it has straight arms. Though, strictly speaking, this breaks the log-periodicity of the structure, it simplifies manufacture and geometrical layout of the antenna. By folding the planar 2-arm log periodic antenna at the feed point, it is possible to achieve wideband directed radiation performance without the need for a cavity structure.

Antenna Magus allows this structure to be designed for a specified operating band and provides bi-directional and uni-directional radiation designs (planar or folded structure respectively.)

The radiation patterns of a folded 2-arm log periodic antenna over a 4:1 band at the lower, centre and upper frequencies in the band.