SPACIS- REXUS/BEXUS Programme

The SPACIS experiment aims at studying the propagation of infrasounds between ground level and the Stratosphere using complex, long duration and limited power sounds, transmitted regularly between one or more ground stations and the gondola during the BEXUS flight. Long duration (tens of seconds) and properly designed signals enable processing gains (correlation) that compensate for a lower power transmission. Low power transmission, based on compressed air release for compactness, unburden the process of transmission, as such sound levels are tolerable to life with minimal care. In short, the SPACIS experiment aims at: •Studying the propagation of low-frequency sound (infrasound) signals between the surface of the Earth and the Stratosphere. •Using complex signals based on pseudo-random sequences to enable detection of low power continuously transmitting sources, providing high granularity of measurements. •Using compact compressed air-based sources of infrasound and pressure sensor-based receivers.