Abstract's details
MAGAL Constellation
CoAuthors
Event: 2022 Ocean Surface Topography Science Team Meeting
Session: Science III: Mesoscale and sub-mesoscale oceanography
Presentation type: Type Poster
Contribution: PDF file
Abstract:
The concept of a small radar altimeter constellation has already been proposed but not yet implemented due to technological limitations or high costs associated with the operation of such a constellation. Yet, some oceanic processes are still poorly studied and understood due to the lack of adequate sampling of the ocean by past and current satellite altimetry missions. With the increase in popularity of the CubeSat concept and the current availability of low-cost and high-performance components, improving the space-time resolution of satellite altimetry with a constellation of small satellites becomes a possible scenario.
The MAGAL Constellation is a future constellation of small satellites carrying radar altimeters that aims to improve the understanding of ocean circulation variability in local, regional, and global scales through improving the spatiotemporal resolution of sea surface topography measurements. By operating as a collective unit, the measurements provided by MAGAL are expected to augment those from the current large satellite radar altimeters. Hence, the framework should be collaborative, to better tackle the gaps of the reference programs, improving the collective data products with an enhanced data set over the open ocean, while also targeting the coastal processes.
Four main use cases have been selected, for which the sampling of the ocean with higher spatial and temporal resolutions is required: better characterization of the mesoscale variability at local and regional scales to support operational oceanography; eddy detection and tracking; monitoring of marine debris pathways, and the monitoring of the water level of inland water bodies.
To achieve these goals, six CubeSat, no larger than 24U, are being considered which, to reduce the launch cost, are all launched simultaneously into the same orbital plane. The orbital characteristics of the constellation have been selected to provide full coverage of the Earth’s surface with a 5-day repetition cycle and distance between adjacent tracks of ~88 km at the Equator. The altitude must be higher than 500 km, to reduce the effect of atmospheric drag, and less than 600 km, due to the restrictions imposed by altimeter and power budget. A sun-synchronous orbit with 97.4° inclination has been selected for repeatability. The separation of the satellites in the orbital plane, as well as orbit corrections, are to be provided by the thruster system.
The MAGAL platform will be miniaturized and manufactured in series, minimizing production, operational and launching costs. The design process will take advantage of the new Space 4.0 industry to integrate readily COTS subsystems (navigation, tracking, cooling and propulsion). Profiting from its low cost, replacement of end-of-life satellites (~3 years) can be accommodated in the same or complementary orbital planes. However, the altimeter payload state-of-the-art demands the development of a new era of small, lower power consuming altimeters.
The radar altimeter will operate at a frequency of 13 GHz, with a Frequency Modulated Continuous Wave (FMCW) architecture. The FMCW architecture was selected as it has a lower power consumption (20 W consumption for 1 W transmission RF power) than traditional pulsed radar altimeters. For this radar altimeter to work correctly, with an adequate observation footprint, the antenna must be at least 1.5 m diameter deployable dish antenna. The signal will then be received and treated using digital signal processing using a FPGA approach.
A Data Analysis Center (DAC) will also be developed based on cloud-based services, surpassing security issues. The DAC will be responsible for storage of acquired data, and processing of those data, including overlay of different layers from multiple sources (e.g. meteorology), in the back-end side, producing scientific and commercial information. A front-end layer will be responsible for displaying processed data in various graphical interfaces, allowing overlaid correlations between data and layers.
The project MAGAL Constellation (Nr. 033688) is co-financed by the European Regional Development Fund through COMPETE 2020, LISBOA 2020 and by FCT under the UT Austin-Portugal interface program, and will consider the insights from the European Union agenda for sustainable development, addressing as many fields of action as possible, and adding value alongside the underlying technology development. Besides providing an integrated approach, bringing together the sea’s economy and its sustainable growth into the future, the MAGAL project will contribute to the knowledge advancement in these fields.
The MAGAL Constellation is a future constellation of small satellites carrying radar altimeters that aims to improve the understanding of ocean circulation variability in local, regional, and global scales through improving the spatiotemporal resolution of sea surface topography measurements. By operating as a collective unit, the measurements provided by MAGAL are expected to augment those from the current large satellite radar altimeters. Hence, the framework should be collaborative, to better tackle the gaps of the reference programs, improving the collective data products with an enhanced data set over the open ocean, while also targeting the coastal processes.
Four main use cases have been selected, for which the sampling of the ocean with higher spatial and temporal resolutions is required: better characterization of the mesoscale variability at local and regional scales to support operational oceanography; eddy detection and tracking; monitoring of marine debris pathways, and the monitoring of the water level of inland water bodies.
To achieve these goals, six CubeSat, no larger than 24U, are being considered which, to reduce the launch cost, are all launched simultaneously into the same orbital plane. The orbital characteristics of the constellation have been selected to provide full coverage of the Earth’s surface with a 5-day repetition cycle and distance between adjacent tracks of ~88 km at the Equator. The altitude must be higher than 500 km, to reduce the effect of atmospheric drag, and less than 600 km, due to the restrictions imposed by altimeter and power budget. A sun-synchronous orbit with 97.4° inclination has been selected for repeatability. The separation of the satellites in the orbital plane, as well as orbit corrections, are to be provided by the thruster system.
The MAGAL platform will be miniaturized and manufactured in series, minimizing production, operational and launching costs. The design process will take advantage of the new Space 4.0 industry to integrate readily COTS subsystems (navigation, tracking, cooling and propulsion). Profiting from its low cost, replacement of end-of-life satellites (~3 years) can be accommodated in the same or complementary orbital planes. However, the altimeter payload state-of-the-art demands the development of a new era of small, lower power consuming altimeters.
The radar altimeter will operate at a frequency of 13 GHz, with a Frequency Modulated Continuous Wave (FMCW) architecture. The FMCW architecture was selected as it has a lower power consumption (20 W consumption for 1 W transmission RF power) than traditional pulsed radar altimeters. For this radar altimeter to work correctly, with an adequate observation footprint, the antenna must be at least 1.5 m diameter deployable dish antenna. The signal will then be received and treated using digital signal processing using a FPGA approach.
A Data Analysis Center (DAC) will also be developed based on cloud-based services, surpassing security issues. The DAC will be responsible for storage of acquired data, and processing of those data, including overlay of different layers from multiple sources (e.g. meteorology), in the back-end side, producing scientific and commercial information. A front-end layer will be responsible for displaying processed data in various graphical interfaces, allowing overlaid correlations between data and layers.
The project MAGAL Constellation (Nr. 033688) is co-financed by the European Regional Development Fund through COMPETE 2020, LISBOA 2020 and by FCT under the UT Austin-Portugal interface program, and will consider the insights from the European Union agenda for sustainable development, addressing as many fields of action as possible, and adding value alongside the underlying technology development. Besides providing an integrated approach, bringing together the sea’s economy and its sustainable growth into the future, the MAGAL project will contribute to the knowledge advancement in these fields.