S-band Dual Polarization Doppler Weather Radar

System Overview

Bilinear polarization radar has now become the development direction of weather radar technology upgrades in various countries in the world. It has obvious advantages in rainstorm monitoring and precipitation estimation accuracy. The first S-band dual-linear polarization radar independently developed by Ninstar was exported to South Korea and successfully passed the on-site test and acceptance of Korean users in August 2009. The system is stable and reliable, and the detection data is true and credible. The BM-100 dual linear polarization radar's digital receiver, signal processing, radar control, product generation and analysis, product display and other complete sets of software use SIGMET products. The rich meteorological products generated by the radar system can fully meet the needs of operations and services such as short-term nowcasting, precipitation estimation, strong weather identification and analysis, wind field analysis, and shear identification.

System composition

BM-100 dual polarization Doppler weather radar consists of antenna and servo system, transmitting system, receiving system, monitoring system, signal processing system, product generation and display system, power distribution system and accessories.

 

Features

  Fully absorb the research results of the U.S. WSR-88D dual-linear polarization upgrade.
  The technical system of double sending and double receiving is adopted.
  Fully apply the online automatic calibration and compensation functions of the S-band single-polarization radar to ensure the detection accuracy of each parameter of the dual-polarization.
  The key components are those already used in the upgrade of the US WSR-88D dual linear polarization.
  It adopts the same working mode as that of the American WSR-88D dual-linear polarization upgrade.

  Using the product generation algorithm of the American WSR-88D radar, it provides users with rich and practical meteorological application products, including: basic products: basic reflectivity, basic speed and basic spectral width;
Export products: Generate a series of analysis and forecast products required by users through powerful meteorological algorithms and processing, such as: echo analysis series, precipitation series, storm tracking and severe weather analysis series, wind field and wind shear series products.

Product advantages

  In business operations, more products are generated, with wider uses and better performance.
  Based on the basic data and products provided by single-polarization radar, dual-polarization radar provides more types and higher quality basic data and products for weather forecasting and service personnel, including differential reflectivity, zero-lag cross-correlation coefficient, depolarization ratio, differential propagation phase shift and differential propagation phase shift rate.
  Based on the zero-lag cross-correlation coefficient, the depolarization ratio and the dual-polarization detection amount, using algorithms such as fuzzy logic, the dual-polarization radar can more accurately distinguish the precipitation type of the detection target (rain, heavy rain, hail, snow, non-meteorological targets, etc.).
  By using the zero-lag cross-correlation coefficient dual-polarization detection, it is possible to further identify ground clutter and non-meteorological echoes, such as super-refractive echoes and ocean wave echoes.
  The dual polarization detection of differential reflectivity and differential propagation phase shift rate provides more accurate observation and analysis results in radar quantitative estimation of precipitation, echo cell analysis, and severe weather warning, and further improves the accuracy of weather forecast.

Main Specifications
 

category	project	technical indicators	Remark
Radome	Working frequency band (MHZ)	2700-3000 _ _
	diameter (m)	11.9	fiberglass foam plastic
	RF Loss ( two-way dB)	≤0.3	multi-layer structure
	Introduced beam bias ( degrees )	≤0.03
	Introduced beamwidth broadening ( degrees )	≤0.03
	Wind resistance (m/s)	≥60	gust
Antenna	shape	paraboloid of revolution
	Reflector diameter (m)	8.54
	Gain (dB)	≥45
	Beamwidth ( degrees )	≤0.99
	First side lobe level (dB)	≤-29
	Far zone sub- lobes (dB)	≤-42
	Polarization mode	linear level
Servo unit	Antenna control word length (bit)	≥13
	Antenna scan mode	PPI , RHI , volume orientation	programmable control,
	Antenna scanning speed ( degrees / second )	36 (max)	Manual or operator control with priority
	Maximum acceleration ( degrees / second2 )	15
	Antenna control accuracy ( degrees )	≤0.1
	Antenna positioning accuracy ( degrees )	≤0.2
	Antenna pitch range ( degrees )	-1 - +92
Transmitter	type	Fully Coherent Amplification Chain	Klystron Final Amplifier
	Working frequency (MHz)	2700-3000
	Peak Power (KW)	≥650
	Transmit pulse width ( uS )	1.57 , 4.71
	Pulse repetition frequency (Hz)	318-1304 _ _
Receiver	IF Frequency (MHz)	57.5491
	Dynamic range (dB)	Log≥94
		Lin≥93	With interference detection device
	Noise figure ( system ) (dB)	≤4.0
Signal processor	Strength Estimation Method	bearing and distance integration	Programmable 32 -bit DSP chip
	speed estimation method	PPP
	warehouse chief	250 meters and multiples	5th order elliptic filter
	Stock number	512	4 - 6 passband width optional
	Ground debris suppression ability	Better than 50dB
RDA monitoring	RDA status monitoring
	RDA failure detection
	Online Calibration
	real-time display Archive A	base data
Product generation	product generation
	product storage
	product distribution
	Radar system monitoring and control
	Archive B	Base Data and Products
	Alarm handling
Product display	product request
	product display
	product storage
	Product Notes and Distribution

 
NJ-38 X-band dual polarization phased array weather radar adopts full coherent pulse Doppler, dual linear polarization and phased array system. The system has the characteristics of high sensitivity, high reliability, convenient operation and maintenance. In order to give full play to the advantages of the phased array, the radar has designed advanced scanning strategies and scanning modes.
The radar is designed for users such as meteorological bureaus, military meteorological support departments, government meteorological departments, civil aviation control departments and industries. The radar can effectively detect and warn the surrounding weather. It can obtain meteorological parameters such as the position, intensity, average radial velocity, velocity spectrum width, and dual polarization of weather targets around the radar station. It can monitor the generation, development, dissipation, and movement of severe convective dangerous weather systems within a range of 240 kilometers in real time.

Features
     NJ-38 X-band dual polarization phased array weather radar adopts full coherent pulse Doppler, dual linear polarization and phased array system. The system has the characteristics of high sensitivity, high reliability, convenient operation and maintenance. In order to give full play to the advantages of the phased array, the radar has designed advanced scanning strategies and scanning modes.
     The radar is designed for users such as meteorological bureaus, military meteorological support departments, government meteorological departments, civil aviation control departments and industries. The radar can effectively detect and warn the surrounding weather. It can obtain meteorological parameters such as the position, intensity, average radial velocity, velocity spectrum width, and dual polarization of weather targets around the radar station. It can monitor the generation, development, dissipation, and movement of severe convective dangerous weather systems within a range of 240 kilometers in real time.

Main feature
• Dual polarization technology of phased array system
• Ultra-low sidelobe antenna technology
• Large-scale active phased array antenna array with high reliability
• Large-scale antenna array precision control technology
• Highly integrated transceiver digitization
• Complex waveform design techniques
• Digital array multi-beam synthesis
Main Specifications
• Technology system
One-dimensional phased array, dual linear polarization, fully coherent pulse Doppler system
• working frequency
9300～9500MHz (point frequency, optional)
• Detection range
Strength measurement distance: ≥240km;
Speed measurement distance: ≥120km;
Dual polarization measurement distance: ≥120km;
Azimuth: 0°～360°;
Pitch: 0°～60°;
Altitude measurement range: 0 ~ 24km;
Intensity range: -15dBZ～+70dBZ;
Speed measurement range: -64m/s～+64m/s (@60km); -96m/s～+96m/s (@30km)
Spectrum width range: 0~16m/s.
• Resolution
Distance resolution: ≤ 75m;
Altimeter resolution: ≤100m;
Intensity resolution: ≤0.5dBZ;
Speed resolution: ≤0.2m/s;
Spectrum resolution: ≤0.2m/s.
• Number of receiving beams: 5 beams (horizontal), 5 beams (vertical)
• Body scan time: ≤ 50s (20-slice scan)
• Ultimate improvement factor: better than 45dB
• Output products: echo intensity (dBZ), echo intensity (dBT), average velocity (V), spectral width (W), differential reflectivity (Zdr), linear depolarization ratio (Ldr), differential transmission phase shift (ФDP), specific differential propagation phase shift (Kdp), and correlation coefficient (ρHV), etc.
• Power supply voltage: three-phase 380V±10%, 50Hz±5%
• Radar power consumption: ≤6kW