Patent attributes
A vector impedance measurement system (100) includes a first radio frequency (RF) source (101) for providing energy to a test circuit. A measurement device (111) is used for providing a first network measurement based upon the voltage and current at the terminals of the test circuit. A second RF source (103) is used for down converting the first network measurement to a second network measurement that is lower in frequency. The vector impedance system (100) operates to calculate a complex impedance using both the magnitude and phase angle of the second network measurement as determined by a processor (133). In that the lower frequency at which signal processing is performed is a fixed frequency, many sensitive parameters of the band pass filters, such as gain and phase shift, can be easily calibrated and do not change during operation, resulting in a simpler calibration process and very accurate data measurements.