Radar wavelength and observing geometry together determine the radar probing spectral width within which the Bragg resonance occurs. In this paper, we present numerical study of radar bistatic scattering from sea surface, and analyze the performance of bistatic radar on observing ocean surface. Bistatic radar in sensing the wave number range, wind speed, and wind direction are comprehensively discussed for general bistatic geometry. Moreover, the frequency dependence is also demonstrated. The results show that, compared to the mono-static radar, bistatic radar exhibits wider covering of the spectrum width, and can better catch the multi-scale marine dynamic process. In addition, bistatic radar, with receiver a slight shift off the specular angle, can capture the scattering of wind-generated high-frequency components of wave spectrum. Therefore, it is expected that bistatic observation provides greater sensing capability of wind field.