Validation Methods For Reflection Factor High Frequency

Abstract

Network analysis is the method by which manufacturers and designers measure the electrical performance of components and circuits used in more complex systems. When these systems are transmitting signals with information content, we are most concerned with getting the signal from one point to another with minimum distortion and maximum efficiency. Vector network analysis is a method of accurately characterizing such components by measuring their effect on the amplitude and phase of swept-frequency and swept-power test signals. In the field of the measurement of S-parameters using a vector network analyzer, the pertinent question is how to calibrate this measuring device high frequency. In fact, calibration is defined by ISO/CEI 17025 “…set of operations that establish, under specified conditions, the relationship between values of quantities indicated by a measuring instrument or measuring system, or values represented by a material measure or a reference material, and the corresponding values realized by standards.”[1] Indeed, calibration is critical to making good VNA S-parameter measurements by given the matrix and complex nature of the measurand, the frequency range and the range of the potentially measured values. While the VNA is a highly-linear receiver and has sufficient spectral purity in its sources to make good measurements, calibration is not directly feasible then we use the notion of calibration, which is to automatically correct the measurement errors. This calibration then allows resetting the response of the instrument to a true predicted value calculated from the measured raw value and the error coefficients determined by the calibration. This correction made to the meter can then be seen as an improvement in its accuracy. So, the calibration of VNA is a validation method to insure the Traceability to SI according to the parameter reflection factor. The topic of this paper is to present a method of calibration of VNA "1- PORT" in order to quantify the terms of errors systematic and validate the primary method “compensated reflectometer” , enrich the park of calibration methods and to meet requirements of ISO / IEC 17025 (Part7.2.2 validation of methods) [1].