Abstract: The use of pulse compression waveforms such as binary phase codes and frequency coded signals enables a high level of resolution required for Earth-based planetary mapping. The ambiguity function is a useful tool that reveals the resolution that can be attained when using a specific waveform. We derived a general expression for the ambiguity function for these random signals to show the resolution for both waveforms. In addition, the expected level of signal self-noise for binary phase codes was determined. The resolutions in delay and Doppler are obtained from the expressions. The resulting plots of derived expected values of ambiguity functions for the random waveforms are given. In addition, plots of the derived expressions for the mean square and variance of the ambiguity functions are also shown for binary phase codes. These show sidelobe behavior (signal self-noise) in delay and Doppler. The square of the mean of the ambiguity functions for each waveform is then convolved with a Gaussian scattering function that models the overspread characteristics of the planet Mars to demonstrate the comparably similar resulting images with negligible spreading. The system parameters required to obtain the images with specified resolutions are compared to show the advantages or disadvantages of using each waveform.!6
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