Class one and class two super-Gaussian spectrum functions are defined firstly in frequency domain
and then their explicit analytic expressions in time domain are deduced.Time operator and frequency operator are introduced to analyse the time
frequency and time-frequency localization characteristics of the aforementioned two new class of functions.Theoretical analysis and results of numerical simulations show that:i)Time operator and frequency operator are very useful mathematical tool for time-frequency analysis;ii)The basic properties of super-Gaussian spectrum functions are useful in constructing orthonormal and almost orthonormal scaling functions and wavelets;iii)The bandwidth of super-Gaussian spectrum functions is decided mainly by their shape factor;the time width of super-Gaussian spectrum functions is controlled chiefly their order;time-frequency localization characteristics of super-Gaussian spectrum functions depend only on their order.