Signal analysis method used for mobile terminal

The invention provides a signal analysis method used for a mobile terminal. The signal analysis method is used for solving the problem of information leakage of terminals. When the mobile terminal receives a system message change indication, a TAC (Tracking Area Code) in the system message changes, and the TAC updating time and the TAC updating frequency are recorded. The mobile terminal sends an access request to an access device and enables a timer, and the terminal receives an identity identification request. In the preset time of the timer, the terminal receives the same signal message rather than a network acceptation message repeatedly, and the TAC of the access device changes. When the timer is overtime, the TAC updating frequency is calculated; if the TAC updating frequency is beyond a threshold value, the connection between the terminal and the access device is cut off at once to avoid information leakage; otherwise, the terminal accesses the network normally for data services. The signal analysis me