This paper studies the relationship between high range resolution and signal bandwidth. In order to generate big bandwidth, a novel spread spectrum radar waveform is present in this paper. This paper derives the ambiguous function of intrapulse and interpulse FM radar waveform. The result proves that this kind of waveform stimulus is of big time duration and big bandwidth. This waveform trades off the drawback of interpulse stepped frequency waveform in range resolution. There is not range ambiguous problem in time domain. According to the distinguishing feature of this kind of waveform, a novel two-stage pulse compression system using surface acoustic wave (SAW) device is put forward. It aims to generate a intrapulse rectangular spectrum by means of SAW device. Then, the system can obtain spread rectangular spectrum using interpulse frequency shifting. After matched pulse compression processing, this waveform holds high resolution in range domain and in velocity domain. The system total compression ratio can be controlled by the intrapulse compression ratio and interpulse compression ratio.