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Measuring the input impedance of a quadrifilar helix antenna

✍ Scribed by Olli P. M. Pekonen; Veli Santomaa; Kalle Kiesi; Murat E. Ermutlu; Kati Wilska

Publisher: John Wiley and Sons
Year: 1998
Tongue: English
Weight: 212 KB
Volume: 17
Category: Article
ISSN: 0895-2477
DOI: 10.1002/(sici)1098-2760(19980205)17:2<102::aid-mop8>3.0.co;2-i

No coin nor oath required. For personal study only.

✦ Synopsis

In this paper, different methods for measuring the input ( ) impedance of a quadrifilar helix QFH antenna are presented along with the underlying physical theory. Shortcomings of the known slotted line method are discussed. New practical and efficient ways of the input impedance deri¨ation based on S-parameters measured at the antenna input ports are introduced. A QFH input impedance is measured with different schemes, and the obtained results are compared and discussed. Finally, the results are concluded.

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