UAV communications have seen a rapid rise in the last few years. The drone class of UAV has particularly become more widespread around the world, and illicit behavior using drones has become a problem. Therefore, localization, tracking, and even taking control of drones have also gained interest. Knowing the frequency of a target signal, its position can be determined (as the angle of arrival with respect to a fixed receiver point) using radio frequency-based localization techniques. One such technique is represented by the subspace-based algorithms that offer highly accurate results. This paper presents the implementation of the MUSIC algorithm on an SDR-based system using a uniform circular antenna array and its experimental evaluation in relevant outdoor environments for drone localization. The results show the capability of the system to indicate the AoA of the target signal. The results are compared with the actual direction computed from the log files of the drone application and validated with a professional direction-finding solution (i.e., Narda SignalShark equipped with the automatic direction-finding antenna).

This paper presents the implementation, evaluation and validation of a radio system solution able to direct the main radiated lobe towards a target user (beamforming). The comprehensive hardware architecture integrates: (1) the transmitting sub-system, (2) the antenna array sub-system, (3) the synchronization sub-system, (4) the receiving sub-system, and (5) the data processing unit sub-system. Two beamforming algorithms are implemented: Minimum Variance Distorsionless Response and Phase Shift beamformer. The radiant system beamforming capacity is evaluated in terms of maximum pointing deviation of the main lobe relative to the direction where the target user is positioned, First Null Beam Width, and antenna gain.

In the context of the Eu:CROPIS mission requirements, this paper aims to test and validate an intra-spacecraft wireless transmission carried between two SpW-to-UWB Wireless Interface Units (WIUs). The WIUs are designed to replace the on-board SpaceWire (SpW) connections of a spacecraft network. The novelty of this solution resides in prototyping and testing proprietary TRL6 WIUs for the implementation of both PDHU and CDHU units, which constitute a spacecraft network. The validation test scenarios employed in this paper were designed under the Eu:CROPIS mission system requirements as defined by the WiSAT-3 European Space Agency (ESA)-funded project. The SpW-to-UWB WIUs run a custom-built ISA100 over an IEEE 802.15.4 UWB PHY layer communication stack. The WIUs are evaluated based on four mission-specific performance test scenarios: (1) the link setup test, (2) the end-to-end delay test, (3) the maximum data rate test and (4) the housekeeping test. The validation test scenarios of the WIUs are carried out with the use of STAR-Dundee SpW-capable equipment. The test results demonstrate the reliability of the deployed SpW-to-UWB WIUs devices for UWB wireless communications carried out within a space shuttle. The SpW data were successfully transmitted across the intra-spacecraft wireless network in all experimental tests. The technology can be considered to be at the maturity level TRL6 (functionality demonstrated in relevant environment) for LEO missions.

In the context of an ever-growing and complex orbital environment, space monitoring and spacecraft tracking is a must when it comes to mitigating space related challenges. In Space Surveillance and Tracking (SST) most radio detection techniques use high-gain directional antennas. Nevertheless, these antennas have a limited field of view (FoV), resulting in low detection probability and tracking duration for Low Earth Orbit (LEO) targets. This research presents an SST experimental hardware solution which is aimed at extending the field of view of a 1.8 m Ku-band parabolic dish by equipping it with a multifeed receiver. The incoming satellite signal undergoes processing and analysis utilizing a National Instruments featured software-defined radio (SDR) platform along with its corresponding software application. The field of view of the proposed solution is determined through simulation and experimental tests using a satellite beacon as a target signal. The research shows promising results regarding the use of multifeed structures in SST.