Atmospheric Radar Research Center

The centerpiece of the National Weather Radar Testbed (NWRT) is the Phased Array Radar (PAR), which was jointly established by NOAA’s National Severe Storms Laboratory (NSSL) and Radar Operations Center (ROC), US Navy’s Office of Naval Research, Lockheed Martin Corporation (LMCO), Federal Aviation Administration (FAA), Basic Commerce & Industries (BCI), the University of Oklahoma (OU), and Oklahoma State Board of Regents [Forsyth et al., 2005]. The NWRT is the nation’s first research facility dedicated to phased array radar meteorology and became available to the community in May 2004.

With the aging WSR-88D network [Serafin and Wilson, 2000], it is important that the technical design and configuration options of the replacement system be thoroughly investigated. In addition to the WSR-88D radar network used for weather observations, numerous other radar systems are currently in operational use in the US with the most visible example being the various FAA’s radars used for both weather monitoring and aircraft surveillance near terminals. Air route surveillance radars are also operated by the FAA for tracking operations on a national scale. With this abundance of radar systems, along with the necessary training, maintenance, and operation costs, there is a significant cost advantage to consider a multi-function radar design [Weber et al., 2005].

Such a multi-function radar would likely be deployed close to ma jor airports and could be used for aircraft surveillance and long-range weather monitoring. Given this multi-function capability, an electronic scanning phased array antenna would be the design of choice.

With this concept as an impetus, a Joint Agency Group (JAG) has been working synergistically to devise a long-term plan for the development of a Multi-function Phased Array Radar (MPAR). With seed funding from the FAA, design options have been studied and prototype modules are being developed by scientists and engineers at MIT’s Lincoln Laboratory [Weber et al., 2005]. Given its integration of the SPY-1A phased array antenna, the NWRT in Norman is currently being used as a platform to study many of the advantages and challenges with phased array technology.

After significant groundwork by NSSL, PAR is now functioning well and will be used for many of our proposed studies. For research involving techniques not yet implemented on PAR or those planned for MPAR, however, the radar simulator will be used as the data source. For example, an investigation of the advantages and disadvantages of possible MPAR digital beamforming algorithms will be carried out using the radar simulator. Given this importance, it is proposed that during the initial phase of the project, the radar simulator will be developed with the capability of generating time-series data under realistic meteorological scenarios. The PI has already begun this research; and, it is anticipated that a relatively short time during the initial months of the project would be needed to adapt the previous work to our PAR/MPAR goals.

Using PAR and/or the radar simulator, it is proposed to pursue two general areas of research:

1. New capabilities of the PAR system should be fully developed to justify phased array technology to the meteorological community. Therefore, cross-beam wind, refractivity retrieval and target tracking will be implemented using PAR with appropriate validation procedures.
2. Research particularly important to phased array radar will be pursued with the goal of system optimization. These topics will include studies of beam multiplexing (BMX) strategies, adaptive array processing for clutter mitigation and resolution enhancement, and waveform design (pulse compression).

Whenever possible, actual PAR data will be used in concert with numerical simulations to enhance our understanding of these areas of research.