The CASES space weather monitor is based on a novel dual frequency L1/L2-C GPS software-defined receiver. The ionospheric products are computed on-board the CASES receiver, and are ready for use. The stand-alone system can output the raw data and ionospheric products via a standard Ethernet or serial (RS232) interface. The Ethernet cable is typically connected to a user’s Internet connection, so that the receiver may be controlled, and the data collected remotely, wherever an Internet connection is available. There is also a version of the CASES receiver with WiFi capability that is available. GPS data and ionospheric products can be stored locally on a hard-drive, USB stick, or SD card. If desired, the user can directly connect to a local PC via RS-232 for local data logging for applications without a network connection.
The CASES receiver has the following specifications:
Form factor/dimensions Rectangular metal enclosure 1.75×7×9 inches (approx H x W x D).
Weight Approx. 2 lbs
Power 7 Watts
Supply voltage +5V (regulated) @ 2 amps (We will provide a very small switching
power supply for 110/220V (50/60 Hz) for AC power)
Communication interfaces RS-232 (DB9), Ethernet (RJ45), WIFI (optional)
The Table below summarizes the CASES data output options. The four columns of the Table indicate different data types, their cadence and whether they are configurable on the receiver. In addition to the typical GPS navigation solution (Column 4), the receiver also provides scintillation parameters (Column 3), TEC and other useful parameters (Column 2), and high-rate raw data that can be used for post-processing (Column 1).
The CASES receiver software is designed to sample the GPS signals at 100Hz, and to output TEC at the rate of once per second (Column 2). The scintillation parameters S4, τ0, and sigma phi (Column 3) are computed inside the receiver and output at a cadence that can be adjusted in the configuration file. S4 and sigma phi are standard deviation measures of received signal power and received signal phase, respectively. τ0 is the decorrelation time of amplitude fluctuations. Processing intervals over which the standard deviations are computed are typically about 1-minute, but are user-selectable in CASES.