A printed LPDA antenna with improved low frequency response

This paper presents a design of a printed log-periodic dipole array (PLPDA) antenna with large operating frequency range from 0.4 GHz to 8 GHz. The proposed antenna design employs a triangular shaped longest dipole element. The triangular shape of the longest dipole element and optimization of the last four dipole element lengths, thicknesses and spacings between them significantly improves the low frequency response. The proposed antenna design provides low return loss demonstrating excellent matching of the antenna. The antenna also provides a reasonable gain of around 5.5 dBi and highly directional characteristics.