Abstract: According to the requirement of radar anti-jamming detection for sea ship target, the design of frequency hopping is usually applied to radar transmitting pulses, which makes target echo phase vary nonlinearly in slow-time. So the conventional fast Fourier transform approach can′t be used to realize coherent integration in this situation. Accordingly, the phase variation of pulse frequency hopping waveform is analyzed, and two new algorithms for inter-pulse frequency hopping waveform coherent integration, specifically the pulse repetition interval-changed approach and factor-changed discrete Fourier transform approach, are proposed. Then the processing details for the coherent integration are demonstrated. The simulation experiment further testifies that both algorithms for processing inter-pulse frequency hopping waveform can obtain the same performance as that for co-frequency pulse waveform.