The parameters estimation of time-frequency overlapped signals is a new subject of communication signals process, it is the base of subsequent processes, such as separation,modulation recognition and signal demodulation of co-channels signals. It shows that signals reflect cyclostationary character after modulation, pulse formation and sampling. This paper presents a method which based on cyclostationary of time-frequency signals, after calculating the cyclic spectrum and making use of mathematic morphology to pick up discrect spectrum-line and estimate modulation parameters, including carrier frequency and chip rate. This algorithm solves the problem of parameter pairs,and make use of mathematic morphology can reduce the background noise effectively. At the same time doing some research about accuracy in the multipath fading