Correlational estimation of parameters of solid state microwave devices

A method is proposed for determining the true variance of parameters of a solid-state microwave device under unfavorable conditions of quality control. This information is needed in development, production, and application of the device, not only because it reveals deficiencies in the design model and in the technological process but also because it is often buried by the complexity of the test equipment and submerged in the sometimes even larger measurement error. The method of estimating the manufacturing variance is a statistical one, a given parameter which characterizes a product lot being sought in the form of a useful signal submerged in interference from all possible distorting factors. Signal and interference are each assumed to be independent random processes, and the resultant dispersion of actual readings is treated as a superposition of both. The standard deviation is determined, accordingly, with use of the correlation coefficient and the confidence range of the latter as well as the adequacy of the sample size are checked against the 3 sigma criterion.