Using GStreamer for acoustic signal processing in deployable sensor nodes

NILUS MK 2 is the newest generation of FFI´s demonstrator system for easily deployable underwater sensor networks. The NILUS MK 2 sensor nodes are battery-operated and equipped with embedded processors running Linux. GStreamer is an open source modular multimedia framework, which we have chosen for implementing acoustic signal processing algorithms in such sensor nodes. We investigate the implementation of beamforming and bearing estimation algorithms in GStreamer for NILUS MK 2. Using data collected during the first NILUS MK 2 trial, the resulting bearings compare well to GPS-based “ground truth”, and online (embedded) and post-trial offline (PC) processing results are in good agreement. Processing requirements are found to be modest, and the additional power consumption due to the acoustic signal processing is marginal. We find GStreamer well suited to acoustic signal processing on deployable sensor nodes.