Global Navigation Satellite System-Reflectometry (GNSS-R) has emerged as a remote sensing tool, which is complementary to traditional monostatic radars, for the retrieval of geophysical parameters related to surface properties. In the present paper, we describe a new polarimetric GNSS-R system, referred to as the GLObal navigation satellite system Reflectometry Instrument (GLORI), dedicated to ...

Normally wind measurements from Doppler radars rely on the presence of rain. During fine weather, insects become a potential radar target for wind measurement. However, it is difficult to separate ground clutter and insect echoes when spectral or polarimetric methods are not available. Archived reflectivity and velocity data from repeated 5 scans provide alternative methods. The probability of ...

Polarimetric radar data have been used to produce microphysical classifications. This kind of analysis is run in a real-time mode from several research radars, including the C-band polarimetric (C-Pol) radar in Darwin, Australia. However, these classifications have had very little systematic evaluation with independent data. Using surface data is often difficult because of sampling issues, part...

Regular operation of weather radar mandates frequent calibration to ensure accurate measurements. Even modest calibration errors in reflectivity factor Z and differential reflectivity ZDR may produce severe deficiencies in the quality of radar products such as rainfall estimates and hydrometeor classes. Radar users, including the Federal Aviation Administration (FAA), rely on high quality weath...

Scientific evidence accumulated over the last decade indicates that weather radar polarimetry has passed two important tests. First, as suggested by theory, polarimetric signals contain significant information about hydrometeor habits; and second, the information can be retrieved with sufficient accuracy to be useful. If it passes the cost effectiveness test, the technique should be adopted for...

Accurate rain estimation from radar measurements has been a difficult task due to the variation of raindrop size distribution (DSD), lack of accurate axis ratio model, measurement error, clutter, and so forth. Previously, rain estimation from weather radars has been largely dependent upon empirical relations such as R-Z relations. The development of polarimetric radar makes accurate rain DSD re...

The subject of this paper is the Colorado State University–University of Chicago–Illinois State Water Survey (CSU–CHILL) National Radar Facility’s S-band polarimetric research radar. Key features of this system include polarization agility (provided by the dual-transmitter, dual-receiver design), a recently updated signal processor, and a low (234 dB, two way) integrated cross-polar ratio (ICPR...

The latest generation of fully polarimetric, ultra wideband, wide angle, low frequency, foliage and ground penetrating synthetic aperture radars presents many new challenges for signal processing. Huge amounts of data need to be processed to focus high quality images. At the same time only a few small subimages contain important information. We investigate the relationship between the focused i...