Coherent multiple-frequency chirp exciter for L band radars

This work presents design examples of coherent multiple-frequency chirp exciter for long distance L band surveillance radars. The implemented technique for pulse compression is the use of linear frequency modulation during the pulse. Long-duration linear FM pulses are obtained by the use of cascade two dispersive SAW delay lines and are converted to the desired carrier frequency. The set of all local oscillator frequencies are obtained by direct frequency synthesis method. All of the frequencies in the synthesizer are derived from the same high stability oscillator source.