An Analysis on Log-Periodic Dipole Antenna

A ten-meter parabolic reflector with crossed LPDA (Long-Periodic Dipole Antenna) feed is planned to be used as the forepart of the developing fast Radio spectrograph in 0.5GHz-1.5GHz at the Yunnan Observatory. In this paper we have designed a FORTRAN program to analyze the electric parameters of the LPDA. And with this program, radiation Patterns, 10dB down beamwidth, gains and input impedence of one LPDA of its two main planes(E plane and H plane) will be given as data files which can be easily converted into figures for any frequency of the bandwidth of the antenna. Some figures, as example, are given at last. This program can be taken as a method to determine the design of LPDA.