Performance assessment of the MUSCLE synthetic aperture sonar

Abstract

Synthetic Aperture Sonar (SAS) systems are quickly becoming fundamental tools for seabed mapping applications, as they provide high resolution imagery independent of range from the sensor, with high area coverage rates. Fundamental in many SAS processing algorithms is the Displaced Phase Center Antenna (DPCA) algorithm, one variant of which uses range-dependent ping-to-ping cross-correlations to help estimate platform movement, which is then used in reconstructing array element locations in order to beam form across the synthetic aperture. SAS image quality can be estimated as a function of signal to noise ratio (SNR), which can be derived from the cross correlation values obtained in the DPCA processing. This paper investigates the performance of the NATO Undersea Research Centre MUSCLE vehicle, equipped with a 300 kHz interferometric SAS with a 60 kHz bandwidth. Performance assessments are shown for a variety of environmental parameters using data collected during four sea trials. SNR measurements are then compared to the values obtained with the NATO sonar performance prediction model ESPRESSO.