A log-periodic cavity-backed slot array

This communication describes the element investigation, design, and testing of a backfire log-periodic cavity-backed slot array operating from 2.8 to 5.9 GHz in a frequency-independent fashion. The gain of the antenna is approximately 10 dB, and the VSWR is below 2.5 to 1. The
H
-plane power patterns are given with nearfield plots along file array. The advantages of the antenna are a simple stripline feeding system and the fact that the structure protrudes a little because shallow cavities are used.