Lossy Audio Compression Applied to Launch Vehicle Acoustic Data

Abstract

This work presents a comparison study using a constant bitrate (CBR) and variable bitrate (VBR) configuration on lossy audio formats, which can be chosen as suitable option to compress spacecraft onboard acoustic data. The acoustic data measured during a rocket motor firing test is assessed by comparing the signal compression rates and information distortions yielded by using those configurations. As a result, the compression algorithm to be used for launch vehicle onboard acoustic measurements is defined. The results have shown that among the lossy formats presented, the OPUS format using the VBR configuration has achieved a compression rate of 254:1 at 5 kbps, saving up to 99.6% the required amount of data to be transmitted through a telemetry link when compared to a non compressed data.