Design and realization of a printed microstrip log-periodic antenna

This paper describes the design and realization of an improved printed microstrip log-periodic antenna (MLPA). The MLPA contains 8 pairs of printed dipole elements, a pair of printed parallel collection lines, a coaxial balun and a series of matching sections to connect the dipole elements and collection lines. In order to feed the collection lines,the coaxial feeder runs along one of the collection line and arrives at the feeding port, where the outer conductor of the coaxial feeder is connected to this collection line and the inner one is connected to another collection line. Test results shows that, the antenna can operate at S/C band with voltage standing-wave ratios (VSWRs) less than 2 and high directional radiation patterns.