119 - Dual Polarization Arrays for compact resilient GNSS Receivers

The ability of exploiting the spatial dimensions has made array antennas valuable for many applications, e.g., multipath and interference mitigation, spatial diversity, and localization. Consequently, over the past years, array antennas, i.e. Controlled Receptions Pattern Antennas (CRPA), have been deployed with GNSS receivers either to provide a spatial filter (null steering techniques) or to improve the SNR level using beamforming techniques. Nonetheless, in order to achieve a high spatial resolution, a large array antenna aperture should be employed. However, in many applications a large array antenna is not possible due to size limitations. Therefore, utilizing dual polarization antennas, instead of single polarization antennas, will provide a compact solution. This compact antenna array antenna exploits a small size while increasing the array antenna degrees of freedom.

Because of the usage of Dual Polarisation, this compact array will enable the following features:

•  High beamforming gain compared to single polarization antenna array of the same size;
•  Higher amount of jamming and spoofing signals mitigation than the number of deployed antennas;
•  Deeper nulls towards interference, spoofing and multipath effect compared to a single polarization array antenna;
•  Accurate Angle of Arrival (AoA) estimations of the satellites genuine signals, jamming and spoofing signals and, reflected multipath signals;
•  The accurate AoA estimates will enable angle-based positioning solutions for resilient coarse PNT solutions, i.e. operation in service denied environments.

The objective of this activity is to design a compact Dual Polarization Arrays Antennas (DPAA) that is suitable for vehicles, plans, drones or mobile devices.

The tasks to be performed shall include:

•  study the state of the art of DPAA systems in the context of navigation;
•  design a dual polarization CRPA that can suppress various jamming and spoofing attacks that vary from low to high power, single to multiple attackers, low to high altitude attacks. Furthermore, include in the design the capability to exploit the dual polarization multiple antennas to estimate the AoA of the genuine signals, jamming and spoofing signals, and reflected multipath signals;
  •  validate the system performance in controlled and real-life environments (target TRL=5), including:
  •  a very high jamming and spoofing suppression gain;
  •  AI-based identification techniques for various jamming and spoofing attacks, and suitable countermeasures;
•  AoA optimized estimation techniques that exploit the spatial and polarization diversities able to provide a coarse positioning and timing solutions in a denied service environment.

The main outputs of the activity will consist of:

•  Design Justification File that contains the outcome of the State-of-the-Art review and the description of the system design;
•  Hardware and Software implementation;
•  Test report

It is noted that no Participating State expressed their opt-out for this activity (EL1-119).