The tracking system

This study presents a complete description of the satellite tracking system used forAryabhata. The total system consists of (i) an interferometry system to measure the direction cosine angles of the satellite with respect to the ground station, (ii) a tone-ranging system to measure the range of the satellite and (iii) a Doppler system to measure the range rate of the satellite. The system accuracies obtained were ±10′ of an arc in the direction cosine angles, ±1.0 km in the range and ±6.6 m/s in the range rate.