Satellite-airborne bistatic time error synchronization method and frequency domain imaging method

The invention discloses a satellite-airborne bistatic time error synchronization method and a frequency domain imaging method, and the method comprises the steps: firstly obtaining direct wave data, carrying out the distance compression of a received direct wave signal, and extracting a one-dimensional vector signal; performing fractional order Fourier transform on the one-dimensional vector signal to extract a time error and construct a time error compensation function, and further performing time error compensation on the target echo signal; in the frequency domain imaging method, azimuth spectrum ambiguity is carried out on a target echo signal without a time error, then a two-dimensional spectrum expression of the target echo signal is obtained through improved point Taylor expansion, and focusing imaging is carried out after the two-dimensional spectrum expression is compensated. The method provided by the invention is realized by virtue of FFT and does not need interpolation processing, so that the imag