Coherent pulse-Doppler radar systems typically transmit pulse-trains made up of identical pulses. While these pulses may contain complex modulation that enhances their ability to separate closely spaced scatterers in delay (range) or Doppler (radial velocity), the fact remains that the pulses making up the pulse-train are usually identical. The aim of this research is to investigate the advantages of pulse-trains made up of pulses that are distinctly different from pulse-to-pulse. This research involves the design of waveform sets and associated signal processing that yield enhanced ability to separate closely spaced scatterers and increase the accuracy of pulse-echo measurements. The problems of diversity waveform measurement (using a fixed set of different pulse-waveforms) as well as adaptive selection of pulse waveforms based on past measurements of the scattering scenario will be considered. The significance of this work lies in the fact that it allows for higher resolution imaging or discrimination of radar scatterers than is possible using a single waveform. Applications that could benefit from this enhanced resolution include synthetic aperture radar imaging, earth based radar astronomy, Doppler weather radar, ionospheric radio sounding, active sonar imaging systems, and monostatic and multistatic radar and sonar tracking systems.
