Space, time, and phase synchronization problems make weak target detection evenmore difficult in the Non-cooperative Passive Bistatic Radar (NPBR) than in conventional radar systems. Therefore, a time and phase synchronization method based on direct waveform parameter estimation and a weak target detection method based on long time coherent integration of a multi-waveform is presented in this paper. First, a universal pulse extraction method based on differential sequence indexing is proposed. Second, an estimation method for the direct waveform parameters, including pulse width, pulse repetition intervals, bandwidth, carrier frequency, and arrival time, is provided. Therefore, by using the estimated waveform parameters, the NPBR time and phase synchronization can be realized. Moreover, based on the waveform parameter estimation, a weak target detection method based on the generalized Radon-Fourier transform of a multi-waveform is provided. Finally, simulation and real data experiments for verifying the effectiveness of the waveform parameter estimation and weak target detection methods are provided.