An adaptive threshold algorithm for detection of pulse radar signals

An adaptive threshold algorithm has been developed in order to achieve a real time waveform reconstruction of IFF radar pulses. In IFF systems, in order to guarantee the receiver selectivity and immunity regarding external interferences, the use of a narrow bandwidth, high order filter is mandatory. This kind of filter introduces an amplitude and phase distortion on received pulses. In order to achieve a correct reconstruction of the received pulses a real time adaptive threshold locked to the pulse amplitude has been developed. Object of the paper is the description of the algorithm and the presentation of the results obtained for detection and reconstruction of IFF (Identification Friends or Foe) pulses.