Abstract: Recently, with the rapid development of electronic device capabilities, the airborne fire control radar faced more urgent challenges in anti-jamming and low probability of intercept requirements. Radar waveform design also requires further development. Traditional radar waveform usually contains modulation in the time, frequency and phase domain dimensions, with relatively poor anti-jamming and low probability of intercept capabilities. This paper proposed a new space-time discrete waveform, which extends the dimensions of radar waveform in spatial scanning and dwell modes. That provided higher degrees of freedom for airborne fire control radar waveform. For the design and processing of space-time discrete waveforms, a space-time discrete scanning mode is established, and a gate lode lobe cancellation method based on pulse extraction is proposed. A discrete scanning waveform optimization model is established based on jitter parameters and inter-group intervals to reduce the sidelobe of doppler signals by waveform parameter optimization. The simulation results indicate that the space-time discrete waveform has less spatial scanning dwell time compared with the traditional sequential scanning waveform. The proposed waveform optimization algorithm can improve the peak sidelobe ratio by more than 15dB, achieving better anti-jamming and low probability intercept performance of airborne fire control radar.