Air Droppable RAMS (ADRAMS) Buoy

Abstract

The ADRAMS buoy was developed to provide remote tracking of drifting sea ice near the Arctic coast. The air droppable feature was employed to reduce the high cost of deployment inherent to manual installation and to provide access to deployment areas and seasons of the year not previously suitable. ADRAMS contains a 401.2 MHz transmitter and suitable digital encoding to allow it to be received by the NIMBUS-6 satellite. This satellite contains a random access measurement system (RAMS) package. The RAMS system determines the position of the ADRAMS buoys to an accuracy of better than 5 KM thru doppler measurements of the received signal. The buoy is deployed via its own parachute and is designed to survive and properly orient its antenna on any type of terrain. The 80 pound package contains enough batteries for 7 to 8 months operation at surface temperatures as low as-50\degC. Although the original ADRAMS was designed for tracking only, it has been modified to incorporate a capability for sensor data telemetry. The RAMS system in the NIMBUS-6 satellite accepts 32 bits of data from each transmission. Nineteen ADRAMS buoys have been deployed thus far; 17 in the Arctic and 2 in the Antarctic. The air drops have been 100% successful.