Patent ID: 6608475
Filing Date: 2003-08-19
Classification: H04B

Abstract:
A network analyzer of the type having a variable frequency signal source applied to a return loss bridge and a reference channel mixer, the reference channel mixer having a variable local oscillator signal input so that the output of the reference channel mixer is at a desired IF frequency, having a test channel mixer coupled to receive a return loss signal from the return loss bridge and the variable local oscillator signal so that the output of the test channel mixer is at the desired IF frequency, and having means for processing the IF frequencies from the reference and test channel mixers to obtain RF measurements for a device under test coupled to the impedance test port further comprising:a first switch coupled to apply the variable local oscillator signal sequentially to the reference and test channel mixers; and a second switch coupled to apply the IF frequencies from the outputs of the reference and test channel mixers sequentially to the processing means.