1. A method for detecting the presence of one or more targets of interest over land, the method comprising: collecting, using a data acquisition system, amplitude data over a period of time from a radar over a coverage area, the amplitude data having amplitude modulations produced by the interaction of radar clutter in the coverage area and one or more targets of interest in the radar coverage; identifying, using at least one processor, frequency characteristics in the amplitude modulations over the period of time; detecting, using the at least one processor, the presence of the one or more targets by: comparing the identified frequency characteristics of the amplitude modulations in the amplitude data produced by modulation of the one or more targets and the radar clutter relative to frequency characteristics of amplitude modulations of the radar clutter without the one or more targets; computing a power spectrum from a time series of the amplitude data and identifying the presence of the one or more targets in the power spectrum above the radar clutter and background spectral noise; converting the amplitude data from log-amplifier data to linear power; computing the FFTs on overlapping azimuths; and match filtering the amplitude data.