Abstract
Abstract. NCAR EOL is
investigating potential configurations for the next-generation airborne
phased array radar (APAR) that is capable of retrieving dynamic and
microphysical characteristics of clouds and precipitation. The APAR will
operate at C band. The APAR will use the electronic scanning (e-scan) feature
to acquire the optimal number of independent samples for recording research-quality measurements. Since the airborne radar has only a limited time for
collecting measurements over a specified region (moving aircraft platform
∼ 100 m s−1), beam
multiplexing will significantly enhance its ability to collect
high-resolution, research-quality measurements. Beam multiplexing reduces
errors in radar measurements while providing rapid updates of scan volumes.
Beamwidth depends on the size of the antenna aperture. Beamwidth and
directivity of elliptical, circular, and rectangular antenna apertures are
compared and radar sensitivity is evaluated for various polarimetric
configurations and transmit–receive (T/R) elements. In the case of polarimetric
measurements, alternate transmit with alternate receive (single-channel
receiver) and simultaneous reception (dual-channel receiver) is compared.
From an overall architecture perspective, element-level digitization of
T/R module versus digital sub-array is considered with
regard to flexibility in adaptive beamforming, polarimetric performance,
calibration, and data quality. Methodologies for calibration of the radar and
removing bias in polarimetric measurements are outlined. The above-mentioned
engineering options are evaluated for realizing an optimal APAR system
suitable for measuring the high temporal and spatial resolutions of Doppler
and polarimetric measurements of precipitation and clouds.
Funder
Directorate for Geosciences
Subject
Atmospheric Science,Geology,Oceanography
Reference28 articles.
1. Balanis, C. A.: Antenna theory: analysis and design, 2nd Edn., Wiley, xvi,
941 pp., New Jersey, USA, 1997.
2. Bluestein, H. B. and Wakimoto, R. M.: Mobile radar observations of severe
convective storms, Vol. 52, Meteorological Monographs, American
Meteorological Society, 105–136, 2003.
3. Brandes, E. A., Zhang, G., and Vivekanandan, J.: Comparison of polarimetric
radar drop size distribution retrieval algorithms, J. Atmos. Ocean. Tech.,
21, 584–598, 2004.
4. Bringi, V. N. and Chandrasekar, V.: Polarimetric Doppler Weather Radar,
Cambridge University Press, New York, 2001.
5. Bringi, V. N., Chandrasekar, V., Balakrishnan, N., and Zrnić, D.: An
Examination of Propagation Effects in Rainfall on Radar Measurements at
Microwave Frequencies, J. Atmos. Ocean. Tech., 7, 829–840, 1990.
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