Compared to the traditional signal, the comb spectrum signal has better reverberation suppression ability. But it is easy to produce Doppler velocity ambiguity. To solve this problem, this paper proposed a new waveform design method of geometric comb spectrum signal. By analyzing the reason of speed fuzzy, we add a set of anti-Doppler frequency interval to reduce the frequency coincidence based on conventional calculation method. Simulation results show that the proposed method can eliminate the spectrum overlap effectively. In noise and reverberation situation, this signal can get an obvious output peak, while avoiding the speed fuzzing. It has better detection performance than traditional comb spectrum signals.