Objective Optimization of Weather Radar Networks for Low-Level Coverage Using a Genetic Algorithm

James M. Kurdzo and Robert D. Palmer, 2012: Objective Optimization of Weather Radar Networks for Low-Level Coverage Using a Genetic Algorithm. J. Atmos. Oceanic Technol., 29, 807–821. doi: http://dx.doi.org/10.1175/JTECH-D-11-00076.1

The current Weather Surveillance Radar-1988 Doppler (WSR-88D) radar network is approaching 20 years of age, leading researchers to begin exploring new opportunities for a next-generation network in the United States. With a vast list of requirements for a new weather radar network, research has provided various approaches to the design and fabrication of such a network. Additionally, new weather radar networks in other countries, as well as networks on smaller scales, must balance a large number of variables in order to operate in the most effective way possible. To offer network designers an objective analysis tool for such decisions, a coverage optimization technique, utilizing a genetic algorithm with a focus on low-level coverage, is presented. Optimization is achieved using a variety of variables and methods, including the use of climatology, population density, and attenuation due to average precipitation conditions. A method to account for terrain blockage in mountainous regions is also presented. Various combinations of multifrequency radar networks are explored, and results are presented in the form of a coverage-based cost–benefit analysis, with considerations for total network

Realities of Rearmament

RIA Novosti yesterday quoted a VVKO spokesman who indicated a second battery of Pantsir-S anti-aircraft gun-missile systems will go into service this fall around Moscow.  For the record, he stated:

“At present, alongside an A-150 missile defense [PRO] division, two    S-400 anti-aircraft missile regiments in two-battalion configurations, deployed in Elektrostal and Dmitrov, provide Moscow with anti-air and anti-missile defense.  One of them already has a ’Pantsir-S’ battery in its composition, in September-October, the second regiment will also receive the same battery complement.”

The spokesman added that, in August, the new Pantsir-S battery, along with its  S-400 regiment at Dmitrov, will be in Ashuluk to perform ‘test’ live firings against low-altitude targets.

Novosti has some video of the Pantsir as does a background piece by Arms-Expo.ru.

Let’s add things up as best we can.

First Deputy Defense Minister Sukhorukov has said the army will get 28 Pantsir-S systems in 2012.  The VVS CINC said there would be two more S-400 regiments (for a total of four) before the end of 2011.  But, there are, as the VVKO spokesman says, still only two.  The CINC also said the next six Pantsir-S systems would be for the Moscow area.  The first four went to Novorossiysk.

Recall there was some question whether ten delivered in 2010 were for Russian forces or some foreign customer.

Source

An Extended Kalman Filter Framework for Polarimetric X-Band Weather Radar Data Processing

Marc Schneebeli and Alexis Berne, 2012: An Extended Kalman Filter Framework for Polarimetric X-Band Weather Radar Data Processing. J. Atmos. Oceanic Technol., 29, 711–730. doi: http://dx.doi.org/10.1175/JTECH-D-10-05053.1

Abstract The different quantities measured by dual-polarization radar systems are closely linked to each other. An extended Kalman filter framework is proposed in order to make use of constraints on individual radar observables that are induced by these relations. This new approach simultaneously estimates the specific differential phase on propagation K_dp, the attenuation-corrected reflectivity at horizontal polarization Z_h, and the attenuation-corrected differential reflectivity Z_dr, as well as the differential phase shift on backscatter δ_hυ. In a simulation experiment it is found that K_dp and δ_hυ can be retrieved with higher accuracy and spatial resolution than existing estimators that solely rely on a smoothed measurement of the differential phase shift Ψ_dp. Attenuation-corrected Z_h was retrieved with an accuracy similar to standard algorithms, but improvements were found for attenuation-corrected Z_dr. In addition, the algorithm can be used for radar calibration by comparing the directly retrieved differential phase shift on propagation Φ_dp with the accumulated K_dp estimates. The extended Kalman filter estimation scheme was applied to data collected with an X-band polarimetric radar in the Swiss Alps in 2010. Radome attenuation appears to be significant (up to 5 dB) in moderate to intense rain events and hence needs to be corrected in order to have reliable quantitative precipitation estimates. Measurements corrected for radome and propagation attenuation were converted into rain-rate R with a newly developed relation between R, K_dp, and Z_dr. The good agreement between rain-rate values inferred from ground observations and from the radar measurements confirms the reliability of the proposed radar processing technique.