The Connected Autonomous Space Environment Sensor (CASES) represents a revolutionary advance in dual frequency GPS space-weather monitoring. CASES is a paperback-novel-sized dual-frequency GPS software receiver with robust dual-frequency tracking performance, stand-alone capability, and complete software upgradability. The receiver tracks L1 and L2 civilian signals (specifically L1 C/A and L2 CL). This dual frequency capability and software upgradability makes the receiver ideal for monitoring space weather events such as total electron content (TEC) variations and scintillation, and the receiver’s low cost allows vast chains of receivers to be set up around the globe. It lies at the heart of the ionospheric monitoring system being developed by ASTRA.
CASES was co-developed by ASTRA, Cornell University and the University of Texas at Austin, with funding provided by the US Air Force, and it is a now commercial product available only from ASTRA LLC. It contains state-of-the-art tracking algorithms that allow the receiver to make high-fidelity measurements, even during the deep power fades that occur during ionospheric scintillation events. Because the receiver tracks L2C and not the military L2 code, the tracking can be done in software and at a fraction of the price of existing commercial GPS scintillation and ionospheric monitoring sensors. With multiple connectivity options, it is a truly versatile receiver that can easily allow global specification of TEC variations and different modes of scintillation. The CASES product has a built-in computer that computes the ionospheric products, so there is no need for an auxiliary computer with additional power and cost requirements, unless additional processing is desired.