Abstract: A power calibration method for a multi-port vector network analyzer (VNA) performs a two-port S-parameter calibration between a pair of ports of the multi-port VNA, and performs a power calibration of one of the ports in the pair of ports. From the two-port S-parameter calibration and the power calibration at the one port, power can be determined at one or more ports of a device under test (DUT) coupled to the ports of the multi-port VNA.

Abstract: Noise power is measured within one or more designated frequency bands of an applied signal. The measurement includes frequency translating the applied signal by a set of equally spaced frequencies to form a corresponding set of intermediate frequency signals, measuring the noise in at least two measurement bands of each of the intermediate frequency signals that are separated by the frequency spacing of the equally spaced frequencies, and determining the noise power in the designated frequency band of the applied signal based on the noise measurements.

Abstract: A modeling method modifies a nominal model for a coaxial standard to provide an enhanced model for the coaxial standard. The nominal model is a nominal reflection coefficient that is phase rotated and impedance transformed to provide an enhanced reflection coefficient that represents the enhanced model. Alternatively, a transmission matrix for the coaxial standard is established and converted to an S-parameter matrix. The enhanced model is then extracted from the nominal model and the S-parameter matrix using network analysis techniques.

Abstract: Method and apparatus to determine scattering coefficients for a device under test (DUT) using a vector network analyzer (VNA) is disclosed. Traditionally, for a DUT having P ports, all combinations of reflective and transmission coefficients are measured and calculated. This is true even for reciprocal devices where SijA=SjiA because, during the measurement, the source and load matches vary. However, the present invention teaches that, for reciprocal devices, only one of the two transmission coefficients between a first port and a second port need be measured. Under the inventive technique, error terms are removed from the measured scattering coefficients. Then, the source and the load matches may be normalized to a normalization match value. The normalization process removes the differences of the source and the load matches.

Abstract: Effects of adapters present only during calibration of a network analyzer are removed. Scattering parameters are obtained for the adapters. For example, the scattering parameters for the adapters are obtained by characterizing the adapters. Systematic error terms for the calibration which remove adapters effects are generated using the scattering parameters for the adapters. In one embodiment, the scattering parameters for the adapters are used to pre-load adapter error terms into the network analyzer before the calibration. The calibration is then performed with the adapter error terms pre-loaded to generate systematic error terms for the calibration. In an alternative embodiment, the calibration is performed (without pre-loading error terms) in order to generate preliminary systematic error terms for the calibration. The preliminary systematic error terms and the scattering parameters for the adapter are used to generate the systematic error terms which do not include effects of the adapters.

Abstract: An error correction method reduces transmission measurement errors and improves measurement accuracy of vector network analyzers. A reflection measurement made using a thruline standard connected between a source port and load port of a transmission/reflection (T/R) test set characterizes the impedance match of the load port while a reflection calibration characterizes the source port. The source port characterization and the load port characterization are then processed to correct a transmission tracking error in subsequent transmission measurements made on a device under test (DUT), without impacting the measurement speed of the VNA. A reflection measurement made with the DUT connected between the source and load port provides a measurement of the DUT's input reflection coefficient, including the effect of the impedance mismatch of the load port. This reflection measurement and the source port characterization are processed to correct a DUT input mismatch error.