Multistatic passive detection with parametric modeling of the IO waveform.

•Examined the target detection problem in the presence of direct-path interference (DPI) for passive multistatic radar using non-cooperative illuminators of opportunity (IO).•Proposed a parametric passive detector by modeling the unknown waveform as an auto-regressive process whose temporal correlation is jointly estimated and exploited for passive detection.•Developed an expectation-maximization based estimator for parameter estimation associated with the parametric passive detector.•Extended several conventional passive detectors, originally introduced for application in DPI-free environments, to provide them with an ability to cope with DPI.