Traditional Doppler velocity estimation method usually requires radiant noise in a high energy line spectrum, which is often less effective for a target without an obvious line spectrum. Considering a moving target radiating a broadband signal whose spectrum has a regular undulating structure and the presence of Doppler shifts will make the structure of the spectrum more complex, we propose a method of Doppler-warping transform combined with the spectrum standard deviation to estimate the velocity of the target. The received signal after the Doppler-warping transform by the correct motion parameters will restore the undulating structure of the sound source signal spectrum, resulting in a significant increase in standard deviation. The Doppler-warping transform result is related to the motion parameters. Therefore, parameters, such as the velocity of a moving target, can be obtained by this method. Both the simulation and the car and motorboat experiment results suggest the effectiveness of this method.