Wide-Band Monopulse Sonar: Processor Performance in the Remote Profiling Application

Monopulse radars are used extensively to track isolated targets to within angular error variances that are very small in comparison with antenna beamwidth. Analogous active sonar configurations (e.g., split-beam sonar) have been in use for several decades, although very little attention has been paid to adaptation of the monopulse concept to accommodate wide-hand operation, or to the angular error variance that is due to a wave phenomenon known in the radar community as "glint." The wide-band adaptation is relatively simple, and permits adjustments in the design of the array processor to reduce glint errors and to avoid anomalous magnification of errors due to ambient noise. This adaptation also has the advantage of being free of angle ambiguities, regardless of the transmitted pulse spectrum. Performance is analyzed for the particular application of remotely measuring the depth/structure profile of the seafloor. Sensitivity to various design parameters is analyzed in detail.