This paper presents processing algorithm for wide-swath spotlight SAR data processing based on spectram analysis (SPECAN).The first step of the proposed algorithm implements SPECAN processing to range dechirped signal.This operation can eliminate azimuth spectrum folding effect and migrate and scale the azimuth data support.Then compensates azimuth quadratic phase and recovers the ideal data support via appropriate interpolation.Finally focuses image with a two-dimensional inverse Fourier transform.Discussed and gave the restriction on the pulse repetition frequency (PRF).Experiments confirm the validity of the presented algorithm.