The inverse electromagnetic scattering problem has been researched for years for its academic significations and widely applications in medical imaging, industrial diagnostics, remote sensing, application geophysics, etc. Recently, one of the research interests in this field is on how to inverse without the phase information of the measured field data, because such information is hard to be measured or easy to be corrupted by noise when the measure system is working on a high frequency rang. Indeed, an amplitude-only measurement can decrease the system cost also.