Log periodic Yagi-Uda array

The log periodic Yagi-Uda array is introduced in this paper. The concept used for extending the frequency bandwidth of the basic Yagi-Uda antenna by employing log periodic principles is presented; and its connection with the log periodic array with parasitic elements is established on the basis of the measured performance. The results of experiments on a log periodic Yagi-Uda dipole array show that the antenna characteristics of the basic antenna are preserved with frequency. Because of the mirror symmetry of the structure, it is shown that a log periodic monopole is realizable.