A GPS Small Rocket Tracking System for Meteorological and Atmospheric Research

NAVSYS has developed a low cost sensor, the TIDGET (TM), which is currently being used for tracking weather balloons, but also has application for small rockets. The TIDGET sensor operates by buffering brief snapshots of GPS data for transmission to a ground processing system through an on-board telemetry link. This simplified the functionality in the rocket payload. Conventional GPS receivers has difficulty in acquiring and tracking the GPS satellite signals under the rocket boost phase dynamics and also are restricted form high altitude operations (>60,000 ft.). The TIDGET can provide reliable operation under dynamics an dover the full rocket trajectory through the use of the enhanced signal processing algorithms in the ground station. This includes an innovative "virtual IMU" process which provides dynamic aiding to the TIDGET tracking process but requires only a single-axis, low cost (~$5) accelerometer to be included in the rocket payload. The existing TIDGET sensor includes logic to interleave the accelerometer and met sensor data with the location data in telemetry downlink. The innovative TIDGET-Small Rocket (TIDGET-SR) tracking system provides highly precise location data throughout all phases of the rocket trajectory without requiring expensive GPS or inertial components.