Abstract：Spectrum informations in the scope of the mainlobe are the main research object of spectrum analysis methods, in which noise component always decreases the accuracy of spectrum analysis. Firstly, the concept of the Mainlobe Spectrum Distortion (MSD), according to the mathematical definition of SNR, is proposed to describe the confidence level of spectrum analysis results quantitatively. Then, to show the obvious relationship between MSD and the error of spectrum analysis, some phase measurements using energy gravity method are carried out as examples, whose results show that, MSD can trace the error curve of phase measurements more closely than that of SNR. Finally, a MSD self-estimation algorithm is provided in details, which can estimate MSD quickly with high accuracy and good anti-noise performance, without measureing the frequency and initial phase.
2013, Vol. 35 
