ABSTRACT
The concepts of resolution and ambiguity were introduced in Chapter 4. The relationship between the waveform resolution (range and Doppler) and its corresponding ambiguity function was discussed and analyzed. It was determined that the goodness of a given waveform is based on its range and Doppler resolutions, which can be analyzed in the context of the ambiguity function. For this purpose, a few common analog radar waveforms were analyzed in Chapter 5. In this chapter, another type of radar waveform based on discrete codes is introduced. This topic has been and continues to be a major research thrust area for many radar scientist, designers, and engineers. Discrete coded waveforms are more effective in improving range characteristics than Doppler (velocity) characteristics. Furthermore, in some radar applications, discrete coded waveforms are heavily favored because of their inherent anti-jamming capabilities. In this chapter, a quick overview of discrete coded waveforms is presented. Three classes of discrete codes are analyzed. They are unmodulated pulse-train codes (uniform and staggered), phase-modulated (binary or polyphase) codes, and frequency modulated codes.
