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IEEE Transactions on Antennas and Propagation
Volume 47 Number 2, February 1999

Table of Contents for this issue

Complete paper in PDF format

Accurate Measurement of Small Input Resistances Using a Conventional Network Analyzer

Ichirou Ida, Member, IEEE, Koichi Ito, Member, IEEE, and Yoshinobu Okano, Student Member, IEEE

Page 389.

Abstract:

Precise and accurate measurement of input resistance is essential to characterize small antennas whose input resistance is very small. However, this is very difficult because uncertainty, which includes imprecision and inaccuracy, sometimes exceeds the resistance being measured. In this paper, a method for precise measurement of small input resistance using a conventional network analyzer is presented. Inaccuracy, which includes an actual conductor loss of antenna under test (A.U.T.), manufacturing error, and the residual systematic errors is then estimated. The former two sources of inaccuracy are obtained by comparing a radiation efficiency measurement of a small loop antenna using the Wheeler cap method with a calculated radiation efficiency. Using these values in the calculation of the input resistance, a true input resistance is acquired. Finally, the actual value of the residual systematic errors for each instrument is estimated by comparison between the true input resistance and the measurement.

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