(Georgia Institute of Technology, 2018-03-08)
Claybrook, Austin W.
The primary mission object of the Ranging And Nanosatellite Guidance Experiment (RANGE)
is the demonstration of precision position determination on the nanosatellite platform expected
to launch in late 2018. RANGE consists of two 1.5U CubeSats each with a high precision GNSS
receiver. The GNSS receiver on each satellite receives GPS pseudoranges and phases in the
civilian L1 and L2 frequencies, which will be used for precision orbit determination. The re ceiver clocks are supplemented by high precision atomic clocks to reduce timing uncertainties.
The satellites also host a near proximity laser ranging system to reduce relative in-track orbit
uncertainties. A preliminary examination of the RANGE mission’s orbit capabilities suggests
a 3σ position uncertainty of less than 10 cm in the radial, intrack and crosstrack direction when
taking GPS measurement once per minute. During select times of higher frequency 1 second
logging, the 3σ position uncertainty in the radial, intrack and cross track directions may be
driven down to the 2.5 cm, 1 cm and 1.5 cm level, respectively. Hardware in the loop simu lations with a GPS signal generator have verified the performance of the CubeSat hardware
against the hardware spec sheets and show increased clock stability when the atomic clock
is used. Once the RANGE missios has launched, ground based laser ranging measurements
provided by the NRL and ILRS will be used to independantly validate the post processed
precision orbit determination solutions of the RANGE mission.