摘要 : In this paper we have proposed a procedure for HEMT's diagnostic based on measurements of phase noise of test oscillator. From phase noise measurement in high frequency range we have estimated parameters of low frequency noise usi... 展开 In this paper we have proposed a procedure for HEMT's diagnostic based on measurements of phase noise of test oscillator. From phase noise measurement in high frequency range we have estimated parameters of low frequency noise using a methodology based on the theory of noise up conversion, and then we have been used these parameters in diagnostic of transistors and to propose a criteria for selection of them. Suggested procedure is suitable for those who are interfered in applying HEMT's in high frequency circuits, because it enables to use noise spectroscopy in HEMT's diagnostic without direct measurements of low frequency noise. Experimental results that illustrate applying of procedure are given. 收起