# Development of the First Portuguese Radar Tracking Sensor for Space Debris
## 5 Conclusions and Future Work  
In this work, we started by doing a review on the current tracking radar systems deployed around the world as well as the networks responsible for SSA and SST tasks (Section 1). Next, we explained the necessity of developing a tracking radar in Portugal and presented the current one in development, ATLAS. An extensive technical description of the system was provided (Section 2) and simulation studies on its expected performance were developed and discussed (Section 3). Since waveform design plays a big role in radar systems, we gave a description of some interesting waveforms that can be used by the system in order to increase the tracking quality (Section 4).  
The system is expected to track targets up to 1000 km in distance with a minimum RCS of 10 cm\({}^{2}\), with an average of 500-700 objects passing hourly in the visible sky. With proper waveform design and processing, it is possible to achieve measurements at 1000 km of range with less than 0.05% error.  
Figure 8: Part of the chirp waveform (**left**) and zero cut of AF (**right**).  
The ATLAS pilot radar was developed with cutting edge hardware technology and uses a highly modular architecture with processing fully in the digital domain. This enables a cost reduction in the development and maintenance of the system and provides a platform for research and innovation in the radar field. We also indicated several emerging fields that can be tested and developed using it, such as matched illumination, noise radar, and cognitive radar (Section 4.2).  
Since the system is at an early stage, several tests and upgrades are envisioned:  
* Calibration campaigns for the antenna motorized tracking system;
* Operational testing in real scenarios;
* Incorporation of the system into an operational SST network;
* Addition of a waveform generator with In-Phase and Quadrature Modulation;  
Conceptualization, J.P., M.B., D.B., and P.M.; investigation and writing, J.P., M.B., J.N., and P.M.; simulations, results and visualization, J.P., M.B., B.C. and V.R.; project administration, M.B. and D.B.; funding acquisition, D.B. and V.R. All authors have read and agreed to the published version of the manuscript.  
The team acknowledges financial support from the Aga Khan Development Network and the Fundacao para a Ciencia e a Technologia, Portugal, for the Science and Technology Cooperation DOPPLER--Development of PaloP know LEdge in Radioastronomy, project number 333197717. V.A.R.M.R. acknowledges financial support from the Fundacao para a Ciencia e Tecnologia (FCT) in the form of an exploratory project of reference IF/00498/2015 and PHOBOS, POCI-01-0145- FEDER-029932, funded by Programa Operacional Competitividade e Internacionalizacao (COMPETE 2020) and FCT, Portugal. The team acknowledges financial support from Enabling Green E-science for the Square Kilometre Array Research Infrastructure (ENGAGE-SKA), POCI-01-0145-FEDER-02217, funded by COMPETE 2020 and FCT, Portugal and from the European Commission H2020 Programme under the grant agreement 2-3 SST2018-20. This work was also funded by FCT and Ministerio da Ciencia, Tecnologia e Ensino Superior (MCTES) through national funds and when applicable co-funded EU funds under the project UIDB/50008/2020-UIDP/50008/2020 and UID/EEA/50008/2019.  
Publicly available datasets were analyzed in this study. This data can be found here: [[https://www.space-track.org](https://www.space-track.org)]([https://www.space-track.org](https://www.space-track.org)).  
The team acknowledges the European Commission Horizon 2020 Programme under the Space Surveillance and Tracking (SST) grant agreement 2-3 SST2018-20.  
The authors declare no conflict of interest.