Improved radar sensitivity through limited sector scanning: The DCAS approach

Distributed Collaborative Adaptive Sensing (DCAS) relies on the use of large numbers of small solid state radars that are spatially distributed to achieve high spatial and temporal resolution throughout the entire troposphere. The radars collaborate with each other via a distributed computing and communications infrastructure, adapting to changing atmospheric conditions in a manner that meets the competing needs of multiple end-users. DCAS radar networks offer the potential to achieve breakthrough improvements in sensitivity and resolution compared to current approaches. Existing full-volume coverage patterns lack the ability to adjust the coverage pattern to the dynamics of the atmosphere thereby sub-optimally sampling the atmosphere. Dwell time may be consumed observing target free atmospheric volumes. By adapting the volume control pattern to observed limited sectors where precipitation and other targets of interest are present, dwell time may be increased improving sensitivity. Volume coverage pattern may be adapted by operating meteorological radar through a closed loop feedback system updating the pattern in response to observed targets. A number of limited sector modes for distributed collaborative adaptive sensing are presented and compared with full-volume coverage patterns. Our analysis shows that sensitivity may be increased by 5 dB and 12 dB by limiting sector azimuth scans to 45° and 30° respectively while maintaining vertical coverage.