The conventional CW (continuous wave) radar provides the velocity information of the moving targets by extracting the Doppler shift in frequencies and indicating them in display units. Tracking in range and tracking in Doppler are, by and large, incorporated in pulse radar operating as MTI (moving target indicator). The paper proposes a tracking circuit to be included in the receiver of the CW radar to make it a tracking system which continuously provides the velocity information about the target being tracked. The main unit of the tracking system is an array of digital band pass filters synthesized in one circuit wherein the tuning is achieved at any instant by selecting one of the desired band pass filters with an analog voltage. When the target under tracking changes its velocity, the filter is automatically tuned to receive the signal of the changed velocity conceding continuous information about the velocity. Since tuning is done by electronic means, the tracking is very fast and the system is dynamic in performance.