Automated double-frequency testing technique for mapping receive interference responses

This paper presents the basic principles of a double-frequency testing technique for highly informative visualization of the linear and nonlinear interference responses of receivers. The technique is implemented with an automated double-frequency test system (DFTS) built around conventional controlling and measuring equipment. The main advantages of DPTS are gained by using the principles of raster-like changing of test signals frequencies combined with visualization of test results as two-dimensional (2-D) raster images of the receiver-under-test double-frequency diagrams (or interference response maps). Basic functionalities of the technique for double-frequency testing, which make possible automated detection and identification of all types of interference in the receiver and measurement of their parameter's, are described. Results of practical implementation of this technique for testing super-high frequency (SHF) receivers, RF amplifiers (RFA) and diode generator are discussed.