Optimal Tapered Band Positioning to Mitigate Flare-End Ringing of Broadband Antennas

摘要

A novel approach is disclosed that mitigates flare-end ringing induced distortion of impulse signals that are transmitted from an electromagnetic radiator. Conventional tapering suppresses energy in the return path by impedance loading the antenna element at the expense of reduced radiation efficiency. This disclosure presents a method that balances the trade-off between radiation efficiency and return path energy suppression while it simultaneously minimizes taper induced signal distortion effects on the front edge of the transmitted impulse. The balance between radiation efficiency, end-fire ringing, and impulse distortion is achieved by placing impedance loading at only at or near the second half of the antenna element. Recent disclosures show the advantage of determining the position of each band through mathematical calculation and by subsequently removing select bands near the feed point to move the reflected pulse away from the front-edge of the transmitted impulse. This disclosure will show that optimal placement of the first tapered band is substantially more critical. The reflection caused by this interface must reach the original impulse at a position that will minimally interfere with its front edge.