Speed measurement is useful for vehicle safety, high speed car performance improvements for better traction control, autonomous vehicles collision avoidance, autonomous navigation. Therefore, it should be precise to have better results for these applications. This paper explores the implementation of a vehicle-mounted Doppler radar for true speed-over-ground (SOG) estimation. Mainly we will use this application for limited series sport vehicles, to make those vehicles better in track performance. This approach provides a resilient data source resistant to wheel slip and independent of satellite reception. The core of this study focuses on Doppler signal spectrum estimation. One approach is by calculating the Doppler power density spectrum and then extracting the dominant frequency component, that is, the peak of the spectrum.