Horus—A Fully Digital Polarimetric Phased Array Radar for Next-Generation Weather Observations

Abstract

Weather radars have become indispensable to meteorologists and the general public for both understanding and awareness of high-impact weather events and as part of the operational warning infrastructure. In the U.S., the operational weather radar network is composed of approximately 160 WSR-88D radars, which are S-band, dish-based, polarimetric Doppler radars. This work reports on the development of a fully digital phased array weather radar that is being used to assess the potential of such technology as a replacement for the WSR-88D radars. The "Horus" radar is a truck-based, S-band, fully digital polarimetric phased array radar. Fully digital systems hold promise for meeting some of the greatest technical challenges facing the meteorological community, such as the effective integration of dual-polarization capability with phased array beam agility. This paper describes the fully digital Horus phased array weather radar that was recently completed by the Advanced Radar Research Center (ARRC) at the University of Oklahoma (OU). An overview of the advantages and challenges facing fully digital arrays for weather observations is provided along with potential mitigation strategies. Initial weather observations with Horus are given with the goal of assessing the radar scanning capabilities and most importantly the polarimetric quality. Finally, a vision for the future of next-generation weather radar operations is given with an eye toward leveraging the scalable design of Horus for highresolution weather observations.

Improvements in the Compression Filter and Calibration Factor of the Progressive Pulse Compression Technique

“…PPC+ has been recently implemented as a software update on PX-1000, and data processed using it can be visualized through the RadarHub (https://radarhub.arrc.ou.edu), offering a variety of practical examples of the performance of PPC+ in different weather scenarios. It has also been implemented in Horus, an all-digital phased array radar recently completed at the ARRC [19][20][21]. The implementation of PPC+ in PX-1000 and Horus is a signifcant contribution since one of the takeouts of this work is that PPC+ can be easily implemented on any radar without any hardware modifcations and with good…”

“…Real-time and archived polarimetric variable felds processed with PPC+ are available through the RadarHub (https://radarhub.arrc.ou.edu), since July 2023. The PPC+ technique has also been implemented in the Horus system, a state-of-the-art fully digital phased array radar recently completed at the ARRC [19][20][21].…”

Fast Adaptive Beamforming for Weather Observations with Convolutional Neural Networks

“…Therefore, DBF can sample a large sector of the atmosphere with an improved temporal resolution by reducing the need for mechanical rotation [4]. The "Horus" radar is a fully digital, S-band, polarimetric PAR that was developed by the Advanced Radar Research Center (ARRC) at the University of Oklahoma, and funded by the National Oceanic and Atmospheric Administration (NOAA) [5]. It is a rotating PAR (RPAR) that can steer the beam electronically in the elevation and/or azimuth and rotate mechanically in the azimuth.…”