3Cat-2—An Experimental Nanosatellite for GNSS-R Earth Observation: Mission Concept and Analysis

Abstract

Abstract-Global Navigation Satellite System Reflectometry (GNSS-R) is a multi-static radar using navigation signals as signals of opportunity. It provides wide-swath and improved spatio-temporal sampling over current space-borne missions. The lack of experimental datasets from space covering signals from multiple constellations (GPS, GLONASS, Galileo and Beidou) at dual-band (L1 and L2), and dual-polarization (Right and Left Hand Circular Polarization: RHCP and LHCP), over the ocean, land and cryosphere remains a bottleneck to further develop these techniques. 3

Spatiotemporal Evaluation of GNSS-R Based on Future Fully Operational Global Multi-GNSS and Eight-LEO Constellations

“…Pervious researchers had also stated some results about the GNSS-R spatial and temporal resolutions, but early simulations were conducted based on GPS and one LEO satellite, and other late results are lack of details [24][25][26][27][28]31]. Here, we describe the simulation and analysis methods, as well as the parameters' values, used in this paper, and conduct the experiments using 119 GNSS satellites and 8 LEO satellites.…”

“…On August 15th, 2016, a Spanish experimental GNSS-R 3 cat-2 satellite with a PYCARO (P (Y) and C/A reflectometer) payload that can receive reflected signals from different GNSS satellites was launched using the CZ-2D (2) rocket at China's Jiuquan Space Center [25]. This mission proves that the four-system GNSS-R system will be feasible in future.…”

3CAT-2: Attitude Determination and Control System for a GNSS-R Earth Observation 6U CubeSat Mission

“…The satellite will operate in a polar Sun-Synchronous Orbit (SSO) with a Local Time of Ascending Node (LTAN) of 12:00 h (AM), and an orbit reference height of ~ 510 km [Carreno-Luengo et al, 2015]. Table 1 collects the expected maximum torques that the satellite will experience in orbit: …”

“…3 Cat-2 cubesat is a research project conducted at Universitat Politècnica de Catalunya aiming at exploring novel GNSS-R techniques, acquire data over different targets to derive algorithms to infer geophysical parameters and demonstrate the reliability of nanosatellites for Earth Observation missions [Carreno-Luengo et al, 2015]. These goals require pointing accuracies up to 7.5º (3σ) for the nadir pointing operating mode.…”

Analysis Model to Optimize Ground Stations in Built-up Areas

“…This increase in the last years of science missions in LEO orbits can be seen in; small satellites projects which integrate CubeSat platform units, such as FIREBIRD placed into orbit by the Delta II rocket to study the Van Allen belts radiation (Crew et al 2015), and Centennial placed into orbit by the ISS to validate a satellite monitoring system from Earth; initiatives of CubeSat constellations (Conklin et al 2013;Leiter, 2013;Subramanian et al 2015;Peral et al 2015;Bandyopadhyay et al 2016), and; experimental studies in CubeSat performances and specific applications (Jones, 2013;Cartwright, 2014;Venturini, 2014;Briggs et al 2015;Fields et al 2015;Westerhoff et al 2015;Carreno-Luengo et al 2016). In addition, the last report …”