Receiving Array Calibration Using DRM Frequency Reference Signal of Direct Wave for HF Passive Bistatic Radar

Based on the characteristics of the digital radio mondiale(DRM),a new method of arraycalibration for high-frequency passive radar(HFPBR)by using frequency reference signal of directwave is proposed.Firstly the signal structure of DRM is introduced,while the feasibility of take fre-quency reference signal as the calibration source is demonstrated.Secondly,taking into account the e-lectromagnetic environment and time-varying non-stationary propagation characteristics,a method ofchoosing high quality direct wave period by the shift-invariant antenna pairs is proposed.Finally,as-sist by the known DRM transmitter position,we utilized this method deal with measured direct wavedata which propagate in surface wave mode and sky wave mode,compared the result of array calibra-tion value with known single frequency signal source.The results showed that the amplitude andphase compensation method in DRM-based HFPBR is effective.