Due to the equivalent phase center error

the imaging quality of the Multiple-Input Multiple-Output synthetic aperture radar (MIMO-SAR) may be degraded with a series of "spurious peaks" in the cross-range direction.Based on a proposed model of MIMO-SAR

this paper derives the analytic expressions for the equivalent phase center error

and its influence on the imaging quality is studied.It is shown that the periodical quadratic phase error is a key factor in the equivalent phase center error

and its compensation may effectively overcome the "spurious peaks".Finally

both theoretical analysis and the numerical experiments are provided to demonstrate the effectiveness of the proposed analysis and compensation methods.