This paper briefly reviews the analysis technique previously published by the authors [Ref 1] which has proven successful for analysis of log-periodic dipole and monopole arrays which include parasitic elements between the driven elements [Ref 2]. The analysis model is an extension of the analysis technique developed by Carrel for the log-periodic dipole array (LPDA) [Ref 3]. The authors have shown that in addition to the coupling between all the radiating elements as developed by Carrel for the analysis of LPDA (where all the elements are connected to the feedline), that the analysis model for LP scaled antenna arrays with parasitic elements requires the inclusion of the coupling between the feed transmission line and the parasitic elements to achieve proper operation. This coupling ideally scales from cell-to-cell by increasing the parasitic element to transmission line separation as the cells increase in size away from the feed point. This paper reviews the importance of this transmission line coupling to the proper operation of the antenna array and how to compensate the antenna's parameters to allow implementation on constant thickness printed circuit board. The paper also briefly covers the group delay properties of the LP antennas showing the group delay is a simple function of only the antenna scale factor τ.
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