Similarities and differences in signal processing for radar and sonar

Examines the differences and similarities between the requirements and execution of digital signal processing in radar and sonar systems. The major differences are caused by the 2×10⁵ ratio in the velocities of propagation of electromagnetics and sound. This results in differences in the bandwidths of the signals employed, the durations of the time windows that can be processed, differences in the ways that Doppler shifts are processed and the urgent need in sonar for the use of beam steering using electronic methods. The wavelengths involved in radar and sonar overlap. At HF radars also need to employ electronic methods to steer beams. The time-bandwidth products involved in radar and sonar are also very similar. The paper also reviews the basic methods of processing in the time, frequency and spatial domains. Spectrum analysis is often the key to the algorithms used