Effective source mismatch uncertainty evaluation using resistive power splitter up to 18 GHz

Abstract

CSIR-National Physical Laboratory (NPL) India is a National Metrology Institute (NMI), which disseminate traceability of the physical parameters in the country. In the field of microwave, it is one of the apex laboratories to provide traceability. In this paper, the method for precession measurement of effective source reflection coefficient using resistive power splitter and mismatch uncertainty evaluation are reported and discussed. Juroshek method is implemented in conjunction with Vector Network Analyzer (VNA) for mismatch uncertainty evaluation by measuring source reflection coefficient from measured S parameters. The measurement results and their associated uncertainty are presented and discussed from 1 MHz to 18 GHz of the resistive power splitter. The complex reflection coefficient of the effective source is determined using indigenously developed automation software. The method adopted is the most convenient way of measuring effective source reflection coefficient whose values are smaller than the manufacturer specs. The mismatch uncertainty has been improved, which is beneficial during the calibration of power sensors along with power meters.