Advances in Weather Radar: Precipitation sensing platforms

Cover
Contents
About the editors
Preface
Acknowledgments
List of editors
List of contributors
List of reviewers
Introduction to volume 1
1 The decade of renaissance in weather radar research
	1.1 Introduction
		1.1.1 Renaissance of weather radar technology
		1.1.2 Shipborne, airborne and satellite radars
		1.1.3 Advances in signal processing
		1.1.4 Disdrometers supporting radar observations
		1.1.5 Scattering from hydrometeors
		1.1.6 Radiowave propagation applications
		1.1.7 Concluding remarks
	References
2 Doppler polarimetric radars for weather observations from 1995 to 2022: a historical perspective
	2.1 Introduction
	2.2 Physical meaning of Doppler polarimetric radar variables
	2.3 Polarimetric radars in research and operations since 1995
		2.3.1 S-band research radars
		2.3.2 C-band research radars
		2.3.3 X-band radars
		2.3.4 Short-wavelength polarimetric radars
		2.3.5 Most recent developments
		2.3.6 Polarimetric upgrade of operational weather radars
	2.4 Weather applications of the Doppler polarimetric radars
		2.4.1 Quantitative precipitation estimation
		2.4.2 Classification of radar echo and hydrometeors
	2.5 Radar polarimetry and cloud microphysics
		2.5.1 Microphysical retrievals
		2.5.2 Thermodynamic retrievals
	2.6 Concluding remarks
	References
3 Developments in solid-state weather radar
	3.1 Introduction
	3.2 Enabling technologies
		3.2.1 Solid-state sources
		3.2.2 Digital transceivers and software radio technology
	3.3 Survey of solid-state weather radar
	3.4 Peak and average power considerations
	3.5 Pulse compression and the matched filter
	3.6 Range sidelobes and their reduction
		3.6.1 Windowing
		3.6.2 Nonlinear frequency modulation
		3.6.3 Predistortion
		3.6.4 Mismatched filters
		3.6.5 Doppler tolerance
	3.7 Blind range and its mitigation
	3.8 Other techniques to increase average power
		3.8.1 Frequency-modulated continuous-wave
		3.8.2 Quadratic phase coding
	3.9 Conclusion
	References
4 Quality of polarimetric data in the WSR-88D system
	4.1 Introduction
	4.2 Required accuracy for WSR-88D measurements
	4.3 Quality of the WSR-88D dual-polarization measurements
		4.3.1 Isolation of the dual-polarization channels
		4.3.2 WSR-88D’s dynamic range
		4.3.3 Reflectivity calibration
		4.3.4 Radar detectability
		4.3.5 ZDR calibration
		4.3.6 Differential phases upon transmission and reception
		4.3.7 Monitoring radar hardware
	4.4 Estimating ZDRsys using weather observations
		4.4.1 Measurements in light rain
		4.4.2 Measurements in dry snow aggregates
		4.4.3 Measurements in regions of Bragg scatter
		4.4.4 ZDRsys across the network
	4.5 Current calibration issues and some possible improvements
		4.5.1 Current WSR-88D calibration issues
		4.5.2 Other data quality enhancements
	4.6 Concluding remarks
	References
5 Improvement of GPM dual-frequency precipitation radar algorithms for Version 07
	5.1 Introduction
		5.1.1 Overview of the DPR
		5.1.2 Overview of DPR algorithms
	5.2 Basic theory
		5.2.1 Drop size distribution
		5.2.2 Retrieval of DSD parameters from unattenuated observations
		5.2.3 Retrieval of DSD parameters from attenuated observations
	5.3 History of the algorithm development
		5.3.1 PR algorithm
		5.3.2 KuPR and KaPR algorithms
		5.3.3 Dual-frequency algorithm
	5.4 Improvement in Version 07
		5.4.1 R–Dm relation
		5.4.2 Correction of SRT considering the soil moisture effect
		5.4.3 Estimation of the vertical profile of
		5.4.4 Correction of scattering tables for PR
		5.4.5 Effects of the change in the precipitation detection method
	5.5 Improvement plan for the next version
		5.5.1 Extrapolation of the vertical profile in the main-lobe clutter region
		5.5.2 Assumptions of precipitation particles
		5.5.3 Differences between PR algorithm and KuPR algorithm
	5.6 Summary
	Acronyms
	References
6 The NASA Polarimetric (NPOL) weather radar facility and some applications
	6.1 The NPOL system
		6.1.1 Transmitter
		6.1.2 Receiver
		6.1.3 Antenna
	6.2 Radar calibration and quality control
		6.2.1 Transmitter, receiver, and antenna calibration
		6.2.2 Calibration techniques using observed data
		6.2.3 Quality control
	6.3 Tools for validation
		6.3.1 Polarimetric radar retrievals
		6.3.2 System for integrating multiplatform data to build the atmospheric column
	6.4 In situ validation
		6.4.1 The Wallops GPM Precipitation Research Facility
		6.4.2 GPM remote field campaigns
	6.5 Validating GPM precipitation retrievals
		6.5.1 Using SIMBA to validate that GPM Level I requirements are met
		6.5.2 Validation of IMERG precipitation using NPOL
		6.5.3 Validation studies using NPOL at Wallops
	6.6 Conclusion
	References
7 NASA high altitude airborne weather radars
	7.1 Introduction
		7.1.1 Motivation for high altitude radars
		7.1.2 ER-2 Doppler radar (EDOP)
		7.1.3 Cloud radar system (CRS)
		7.1.4 High-altitude wind and rain airborne profiler (HIWRAP)
		7.1.5 ER-2 X-band radar (EXRAD)
	7.2 Airborne radar challenges
		7.2.1 Pulse compression and surface backscatter
		7.2.2 Doppler algorithms
	7.3 Calibration
		7.3.1 Internal calibration
		7.3.2 Ocean calibration
	7.4 Applications: precipitation physics
		7.4.1 Differential measurements
		7.4.2 Microphysical retrieval method
		7.4.3 Attenuation correction
		7.4.4 Four frequency nadir measurements
	7.5 Applications: horizontal wind retrievals
		7.5.1 Dual-Doppler technique
		7.5.2 Coplane technique
		7.5.3 Velocity-azimuth display (VAD) technique
		7.5.4 Three-dimensional variational technique
	7.6 Future developments
	References
8 Ocean-going weather and profiling radar for clouds and precipitation
	8.1 Introduction
	8.2 Some historical perspectives
		8.2.1 Shipborne radars by the Japan Meteorological Agency (JMA)
		8.2.2 GATE (Global Atmospheric Research Program (GARP) Atlantic Tropical Experiment – 1974)
		8.2.3 TOGA-COARE: Doppler radars and profilers
		8.2.4 Doppler weather radar applications post-TOGA COARE
		8.2.5 The coming of shipborne dual-polarization radars
	8.3 Three current shipborne C-band dual-polarization radars
	8.4 Technical challenges and approaches for shipborne dual-polarization weather radar
		8.4.1 Blockage
		8.4.2 Antenna stabilization
		8.4.3 Sea clutter
		8.4.4 Quality control: calibration
		8.4.5 Quality control: dual-polarization weather radar post-processing
		8.4.6 Dual-polarization weather radar performance
		8.4.7 Some examples of dual-polarization data and science applications
	8.5 Weather and cloud profiling radars on ships
		8.5.1 History of cloud radar deployments and outcomes
		8.5.2 Technical descriptions
		8.5.3 Capabilities and science applications
	8.6 Current and future capabilities and opportunities
	Acknowledgments
	References
9 A versatile stratosphere–troposphere radar at 205 MHz in the tropics
	9.1 Stratosphere–troposphere (ST) radar
		9.1.1 Concept of 200 MHz ST radar
		9.1.2 Advantages of 200 MHz radar
		9.1.3 ST radar at Cochin University of Science and Technology
		9.1.4 Geographical relevance
		9.1.5 Refractive index structure constant (C2
n) over Cochin
	9.2 Technical specifications of CUSAT ST radar
		9.2.1 Radar-processing computer
		9.2.2 Coherent signal generator
		9.2.3 Signal processing
		9.2.4 Mode of operation
		9.2.5 Doppler beam swinging
		9.2.6 Yagi–Uda antenna for ST radar
		9.2.7 Total transmitted power
		9.2.8 TRM
		9.2.9 Radiation pattern measurement
		9.2.10 Noise level survey between the radar site and a TV broadcasting station
	9.3 Research to enhance the acceptability of ST radar data
		9.3.1 Validation of radar wind observations with GPS radiosonde
		9.3.2 Evaluation of ST radar wind observations with reanalysis and model outputs
		9.3.3 Radar observations under rainy conditions
		9.3.4 New technique for the identification of clear air and rain echoes
		9.3.5 Validation of Aeolus satellite wind observations with the CUSAT ST radar
		9.3.6 Higher height coverage of CUSAT ST radar
	9.4 Atmospheric studies using the 205 MHz ST radar
		9.4.1 Vertical structure and evolution of Indian summer monsoon
		9.4.2 Diurnal variations during the active and break phases of monsoon
		9.4.3 Thunderstorms observations from ST radar
		9.4.4 Determination of tropical tropopause using ST radar observations
		9.4.5 Tropopause variability and associated dynamics during monsoon
		9.4.6 Features of atmospheric circulation observed during sudden stratospheric warming
		9.4.7 Detection of inertia gravity waves
	9.5 Potential of 205 MHz ST radar for ionospheric observations
		9.5.1 Configuration of 205 MHz ST radar for ionospheric observations
		9.5.2 Significant ionospheric observations using the 205 MHz ST radar
		9.5.3 Detection of ionospheric disturbances with volcanic eruption and Tsunami
	9.6 Other observations by 205 MHz ST radar
		9.6.1 Detection of electric charges in the upper atmosphere
		9.6.2 Flight tracking using ST radar
		9.6.3 Meteor observation from ST radar
	9.7 Curious observational evidence from ST radar
		9.7.1 Rotational Doppler at melting layer
		9.7.2 Single-sided Doppler at 90 km
		9.7.3 Anomalous precipitation-like pattern observed from the tropopause level
	9.8 Application of 205 MHz radar for radio astronomical studies
	9.9 Future perspective
		9.9.1 Imaging of the atmosphere
	Acknowledgments
	References
10 An integrated future US weather radar architecture for aviation
	10.1 Introduction
	10.2 Airport meteorological radar development
		10.2.1 Terminal Doppler Weather Radar
		10.2.2 Airport surveillance radar
	10.3 Multi-agency weather and aircraft surveillance radar concept development
		10.3.1 Multifunction phased array radar
		10.3.2 Benefits for public weather warning and water management
	10.4 The future national weather radar system
		10.4.1 Opportunities
		10.4.2 Architecture framework
		10.4.3 Roadmap for transition to the future architecture
	Appendix “Weather optimized” airport surveillance radar
	References
11 The mitigation of ground clutter
	11.1 Historical perspective and background
		11.1.1 Ground-clutter statistics
		11.1.2 Ground-clutter identification
		11.1.3 Ground-clutter filtering
		11.1.4 Wind turbine clutter
		11.1.5 Phased array technology
	11.2 A comparison of spectral and regression clutter filtering
		11.2.1 Spectral clutter filter and Fourier basis functions
		11.2.2 Regression filtering and orthogonal polynomials
		11.2.3 The frequency response of the regression filter
	11.3 Operational aspects of regression clutter filtering
		11.3.1 Automated selection of the polynomial order
		11.3.2 Interpolation across the zero-velocity gap
	11.4 Identifying low CSR clutter
		11.4.1 RHOHV-test example
	11.5 Regression and spectral clutter filter comparison using experimental data
	11.6 Summary
	Acknowledgment
	References
12 Polarimetric planar phased array radar – challenges for observing weather
	12.1 Introduction
	12.2 Radiating elements
		12.2.1 Electric dipole
		12.2.2 Magnetic dipole
		12.2.3 Collinear electric and magnetic dipoles
		12.2.4 Patch radiators
		12.2.5 Array antenna
	12.3 Polarimetric modes and effects of pattern on bias in the polarimetric variables
		12.3.1 Operational polarimetric modes
		12.3.2 Cross-polar pattern effects on bias in polarimetric variables
		12.3.3 Copolar pattern effects
		12.3.4 Phase coding
		12.3.5 Alternate transmission of H and V field (AHV)
	12.4 Vertically oriented array
		12.4.1 Relations
		12.4.2 Simultaneous transmission with phase coding
		12.4.3 Polarimetric variables
		12.4.4 Simultaneous transmission without phase coding
		12.4.5 Alternate transmission AHV
		12.4.6 Principal planes
	12.5 Tilted antenna array
	12.6 Examples
	12.7 Conclusions
	Appendix
	References
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