Signal detection method for small mobile master user

The invention relates to the technical field of signal detection, in particular to a signal detection method of a small mobile primary user, which is used for a system consisting of a small primary user and a plurality of secondary users, and comprises the following steps: S1, receiving, by the secondary users, the data of signals of the small mobile primary user; s2, forming a sampling signal matrix X by the data; s3, solving a sampling covariance matrix R (Ns) of the sampling signal matrix X; s4, solving a maximum characteristic value and a minimum characteristic value of the sampling covariance matrix R (Ns), and solving a detection quantity T according to the maximum characteristic value and the minimum characteristic value; s5, setting a false alarm probability, and determining a judgment threshold gamma of the detection quantity T according to the false alarm probability; and s6, judging whether a main user signal exists or not according to the relation between the detection quantity T and a judgment th