Electronically steered cognitive weather radar - a technology perspective

Long-range mechanically rotating weather radar systems currently in use suffer from inherent performance limitations including coarse resolution, long update time and beam blockage. More importantly their long-range sensing approach prevents sufficient monitoring of the lower troposphere below a height of 1 km. Social significance of such a lack of capability extends up to hinder a timely reaction to important short term weather phenomena such as tornadoes. Conversely, a short-range sensing strategy could address most of these limitations. Even though X-band units have been shown able to provide quantitative precipitation estimations (QPE), the need for Doppler information in the H and V polarizations, together with complex mechanically rotating parts and bulky radome, prevented so far the deployment of large numbers of inexpensive X-band radars able to offer a data quality equivalent to their long-range counterparts. Exploiting recent hardware breakthroughs, it is now possible to develop a new generation of electronically steered short-range weather radars suitable for low-cost civilian applications and featuring dual polarization with Doppler capabilities. Supported by a fully digital hardware core, adoption of the novel cognitive radar paradigm is also here proposed as an approach to achieve optimal use of newly available sensing resources.