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GB 31223-2014: Specifications for meteorological observing environs protection -- Weather radar station
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Basic data
| Standard ID | GB 31223-2014 (GB31223-2014) |
| Description (Translated English) | Specifications for meteorological observing environs protection -- Weather radar station |
| Sector / Industry | National Standard |
| Classification of Chinese Standard | A47 |
| Classification of International Standard | 07.060 |
| Word Count Estimation | 24,250 |
| Date of Issue | 9/30/2014 |
| Date of Implementation | 1/1/2015 |
| Quoted Standard | GB 4824-2004; GB 13618-1992 |
| Regulation (derived from) | People's Republic of China Announcement of Newly Approved National Standards 2014 No. 22 |
| Issuing agency(ies) | General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of the People's Republic of China |
| Summary | This Standard specifies weather radar detection range and environmental requirements. This Standard is applicable to weather radar to detect environmental protection activities. |
GB 31223-2014: Specifications for meteorological observing environs protection -- Weather radar station
---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.
Specifications for meteorological observing environs protection.Weather radar station
ICS 07.060
A47
National Standards of People's Republic of China
Meteorological environmental protection norms Weather Radar
Published 2014-09-30
2015-01-01 implementation
Administration of Quality Supervision, Inspection and Quarantine of People's Republic of China
Standardization Administration of China issued
Table of Contents
Preface Ⅰ
Introduction Ⅱ
1 Scope 1
2 Normative References 1
Terms and definitions 1 3
4 scope of protection 2
5 2 protection requirements
Measurement Method 4 6
Annex A (normative) Weather radar antenna electromagnetic radiation zone calculation method 5
Annex B (normative) clearance calculated weather radar protection 7
Annex C (normative) obstacle occlusion limit angle calculation capacity 11
Annex D (informative) for weather radar interference voltage sources of interference and the minimum margin value calculated pitch protection
Calculation Example 13
Annex E (normative) obstacle elevation and azimuth with the restriction altitude limit width measurement and calculation methods 15
Reference 19
Foreword
All technical content of this standard is mandatory.
This standard was drafted in accordance with rules GB/T 1.1-2009 given.
The standard proposed by the China Meteorological Administration.
This standard by the national meteorological Standardization Technical Committee (SAC/TC507) instruments and methods of observation.
Drafted by. China Meteorological Administration meteorological centers, Fujian Meteorological Bureau, Guizhou Provincial Meteorological Bureau, the Liaoning Provincial Meteorological Bureau.
The main drafters of this standard. Daren Chen, high Yuchun, Li Lin, Zhang Hu students, Wu Taiwang, Chai Xiumei, Cheng Fei, Li Zhe, Guo Rui, Chen Bao.
Introduction
Weather radar is to monitor the typhoon, heavy rain, hail, tornadoes, downburst and other disastrous weather system for disaster prevention and mitigation, to protect people's life and property
Important remote sensing equipment production safety, short-term nowcasting warning to provide a scientific basis for decisions. To protect the environment, weather radar detection, charge
Minutes played using weather radar performance, formulated standards.
Meteorological environmental protection norms Weather Radar
1 Scope
This standard specifies the scope and requirements of the weather radar to detect environmental protection.
This standard applies to weather radar to detect environmental protection activities.
2 Normative references
The following documents for the application of this document is essential. For dated references, only applies to the version dated paper
Pieces. For undated references, the latest edition (including any amendments) applies to this document.
GB 4824-2004 industrial, scientific and medical (ISM) radio disturbance characteristics Limits apparatus and methods of measurement (CISPR11.
2003, IDT)
GB air intelligence radar station on the electromagnetic environment protection requirements 13618-1992
3 Terms and Definitions
The following terms and definitions apply to this document.
3.1
Weather radar weatherradarstation
Weather radar by the operating environment and equipment to meet the requirements of the facility and its spatial composition.
Note. weather radar is based on scattering clouds, fog, rain, snow and other particles and electromagnetic wave generation principle Doppler effect and the like, and detect the Doppler velocity echo intensity rainfall
And the evolution of the spatial distribution, and thus precipitation weather surveillance radar tracking system.
3.2
Beamwidth beamwidth
Antenna pattern angle between the direction of maximum radiation two half-power points.
3.3
Obstacle obstacle
Generating object and the shielding effect on high frequency electromagnetic waves emitted and received by the radar.
3.4
Isolated obstacles isolatedobstacle
Obstacle adjacent lateral spacing is greater than 2 azimuth beamwidth and not greater than the tolerance value shielding obstacle.
3.5
Blocking elevation blockelevationangle
Start from the radar minimum operational elevation angle of the lifting beam away from the obstacle until its lower edge, i.e. from the occlusion to occlusion on the presence of
The beam angle of the edge lifting disappears.
3.6
Occlusion azimuth blockazimuthangle
Blocking obstacle beamforming radar, which radar beam edge orientation (-3dB) into the barrier region, and the edge of the radar beam
(-3dB) when the angle between the orientation in which the exit obstacle region.
3.7
Total occlusion azimuth totalblockangleinazimuth
All occlusion sum azimuth angle.
3.8
Obstacle limitation altitude restrictedaltitudeforobstacle
The maximum allowed blocking obstacle elevation of the highest point is located calculated altitude.
3.9
Obstacle limitation azimuth width restrictedazimuthwidthforobstacle
The width of the obstacle obtained by calculating the maximum allowable occlusion azimuth.
3.10
Headroom clearance
Weather radar based business work at the lowest elevation, antenna main beam is not obstructed detection environment.
4 scope of protection
4.1 General
Weather radar detection range of environmental protection and the protection zone consists of a two protected areas, the scope of illustration and description in Appendix A. In the days
There should be no other air Zhou Bian the radar station interference affecting the normal operation of the radar. For electromagnetic interference protection scope is not limited to one, two
Level protected areas.
4.2 a protected area
The near-field region of radiation above and below the weather radar radar antenna port 10 along the vertical parallel lines radar wavelength transition region "side
Edge "area thereof.
4.3 two protected areas
In weather radar as the center from the outer edge of a protected area to the distance from the radar 20km annular region.
5 protection requirements
5.1 General
5.1.1 obstacle to echo strength loss caused by weather radar should not exceed 1dB.
5.1.2 radar receiver sensitivity loss due to the inevitable interference active should not exceed 1dB.
5.2 a protected area
5.2.1 There should be no obstacles blocking caused by weather radar.
5.2.2 limit altitude corresponding to h2 by formula (1) is calculated, see the illustration and description B.1.
h2 =
h1-10λ 0 \u003cd≤D2/2λ 10λ/tan(180λ/πD)
h1 D/2-d × tan (180λ/πD) D2/2λ 10λ/tan (180λ/πD) \u003cd≤2D2/λ{ (1)
Where.
H2 --- radar antenna to limit the horizontal scanning altitudes of the highest point of the object, in meters (m);
Point along the altitude h1 of the radar antenna port --- in meters (m);
--- radar wavelength [lambda], in meters (m);
D --- the radar antenna to the level of the highest point along the mouth of the object point distance in meters (m);
D --- radar antenna diameter, in meters (m).
5.3 two protected areas
5.3.1 isolated obstacles block the elevation limit
Radar at the lowest elevation, isolated from blocking the elevation tolerance values in Table C.1, the calculation method, see Appendix C.
5.3.2 obstructions azimuth limitation
Radar at the lowest elevation, azimuth isolated obstructions Table C.1 tolerance value, calculated in Appendix C.
All Zhou Bian obstacles total occlusion azimuth angle greater than 5 °.
5.3.3 height restrictions
Obstacle altitude limit according to formula (2) is calculated, and schematic description see B.2.1.
h3 = h1 (D/2) × cosφ [d (D/2) × sinφ] × tan (φ-θ/2 β), d > 2D2/λ (2)
Where.
H3 --- elevation occlusion margin value β corresponding to the highest point of the obstacle limit altitude in meters (m);
D --- the radar antenna port in the point to the horizontal distance of the highest point of the obstacle, in meters (m);
--- obstacle beta] corresponding to the highest point of elevation occlusion tolerance value, in degrees ([deg.]);
[Phi] --- traffic mode radar minimum operational elevation in degrees ([deg.]);
--- radar antenna beam width [theta], in degrees ([deg.]);
h1, D --- in formula (1).
5.3.4 azimuth width restrictions
Isolated obstacles limit the width of the azimuth according to formula (3) is calculated, see the illustration and description B.2.2.
b = 2 × d1 × tan (Ψ/2) (3)
Where.
B --- blocking position limits the width of the radar beam isolated obstacle, in meters (m);
--- D1 obstacle arbitrary point corresponding to the obstacle shielding azimuth angle (in the center of the radar antenna as the central angle) at the point of chord
Distance from the center of the radar antenna, in meters (m);
Occlusion azimuth tolerance value [Psi] --- obstacle in degrees (°).
5.4 Electromagnetic Interference
Weather radar Zhou Bian, tolerance limit interference voltage other electronic devices in the radar frequency spectrum occupied and should meet
Specified in Table 1.
Table 1 tolerable limit interference voltage
Frequency Range/GHz 2.7 ~ 3.0 5.3 ~ 5.7 9.3 ~ 9.7
Interference voltage tolerance value/μV 0.40 0.43 0.44
NOTE. interference voltage margin value 2.7GHz ~ 3.0GHz frequency band is taken from GB 13618-1992; 5.3GHz ~ 5.7GHz, 9.3GHz ~ 9.7GHz Frequency
Interference voltage tolerance value calculation methods section D.1.
5.5 Minimum distance protection
The minimum distance protection with typical weather radar interference source should satisfy specified in Table 2.
Table 2 Minimum distance protection margin value
Sources of interference
Minimum distance protection
km
2.7GHz ~ 3.0GHz 5.3GHz ~ 5.7GHz 9.3GHz ~ 9.7GHz
High-voltage overhead transmission line
500kV 1.00 0.30 0.10
220kV ~ 330kV 0.80 0.24 0.08
110kV 0.70 0.21 0.07
High-voltage substation
500kV 1.20 0.36 0.12
220kV ~ 330kV 0.80 0.24 0.08
110kV 0.70 0.21 0.07
Electrified railway electric locomotive 0.70 0.34 0.18
Non-electrified railway 0.50 0.24 0.13
Car road
High speed, a 0.70 0.42 0.26
Two 0.70 0.42 0.26
High frequency of 1.20 0.56 0.27
Note. The minimum margin value protective pitch 2.7GHz ~ 3.0GHz frequency band is taken from GB 13618-1992; 5.3GHz ~ 5.7GHz, 9.3GHz ~
Minimum tolerable limit guard band spacing 9.7GHz see calculation example D.2.
6 Measurement Method
6.1 obstacle measurement and calculation methods
6.1.1 measuring equipment
Angle measurement accuracy should be less than 2 ", from the total station measurement accuracy should be less than 1.5mm.
6.1.2 Measurement and Calculation Method obstacle
Obstacle altitude, altitude limitations and restrictions azimuth width measurement and calculation methods in accordance with the Appendix E.
6.2 Electromagnetic interference measurements
6.2.1 measuring equipment
As used interference measurement apparatus should meet the requirements of 6.2 GB 4824-2004.
6.2.2 measuring program
8.4 in accordance with the requirements of GB 4824-2004.
Appendix A
(Normative)
Weather radar antenna electromagnetic radiation field region Calculation
A.1 electromagnetic radiation field around the weather radar antenna area into the radiation near field and far field radiation, shown in Figure A.1, A.2 is a plan FIG.
Schematic view.
Description.
1 --- shaded protected area, 0 \u003cd2≤2D2/λ;
Parallel beam region, 0 \u003cd1≤D2/2λ;
h = 10λ;
Above and below the upper and lower radar antenna port 10 along an extension line of the wavelength of the radar parallel lines, D2/2λ \u003cd4≤D2/2λ 10λ/tan(180λ/πD);
2 --- to 20km outside the shadow of the two protected areas, 2D2/λ \u003cd3≤20km;
3 --- beam "edge" (corresponding to the "edge" of the transition zone).
A.1 schematic view field region of electromagnetic radiation and protected areas
Description.
1 --- a protected area, 0 \u003cd1≤2D2/λ;
2 --- two protected areas, 2D2/λ \u003cd2≤20km。
Figure A.2 electromagnetic radiation field region and a schematic plan view of protected areas
A.2 respect to the aperture of the antenna, the radiation near field range calculated according to formula (A.1).
0 \u003cd≤2D2/λ (A.1)
Where.
D --- point viewing distance to the antenna in meters (m);
D --- radar antenna diameter, in meters (m);
--- radar wavelength [lambda], in meters (m).
Where 0 \u003cd≤D2/2λ为平行波束区,D2/2λ\u003cd≤2D2/λ为过渡区。
A.3 for the range of the antenna aperture, radiation in the far field region according to equation (A.2) is calculated.
d > 2D2/λ (A.2)
Where.
D --- point viewing distance to the antenna in meters (m);
D --- radar antenna diameter, in meters (m);
--- radar wavelength [lambda], in meters (m).
Appendix B
(Normative)
Weather radar protection clearance calculation method
B.1 radar antenna radiation environmental clearance calculated near-field region
B.1.1 collimated beam region and the extension region obstacle height limit calculated altitude
Parallel beam region, radiated from the antenna the radar energy is concentrated in the cylindrical space having a diameter D propagation, consider engineering practice
Experience, to near-field region above and below the radar antenna port 10 and down along the parallel lines of the radar wavelength radar headroom baseline environmental protection,
Be the corresponding extension (extension configuration) protected from. Limit altitude corresponding to the formula in Figure B.1 (B.1) is calculated.
h2 = h1-10λ, 0 \u003cd≤D2/2λ 10λ/tan(180λ/πD) (B.1)
Where.
H2 --- radar antenna to limit the horizontal scanning altitudes of the highest point of the object, in meters (m);
Point along the altitude h1 of the radar antenna port --- in meters (m);
--- radar wavelength [lambda], in meters (m);
D --- the radar antenna port object point to the highest point along the horizontal distance in meters (m).
Description.
1 --- beam centerline, h = 10λ;
A --- when the radar antenna is not just caused by the horizontal scanning an object altitude limit point of occlusion;
--- C under point along the radar antenna port;
O --- radar antenna center point (feed).
FIG schematic elevation height B.1 parallel beam region and object region extending limit
Limit height calculation method altitude B.1.2 transition zone
Transition zone with its "edge" baseline environmental clearance for the radar. Limit altitude corresponding to the formula in Figure B.2 (B.2) is calculated.
h2 = h1 D/2-d × tan (180λ/πD), D2/2λ 10λ/tan (180λ/πD) \u003cd≤2D2/λ (B.2)
Where.
H2 --- radar antenna to limit the horizontal scanning altitudes of the highest point of the object, in meters (m);
Point along the altitude h1 of the radar antenna port --- in meters (m);
--- radar wavelength [lambda], in meters (m);
D --- radar antenna diameter, in meters (m);
D --- the radar antenna port object point to the highest point along the horizontal distance in meters (m).
Description.
1 --- beam "edge";
2 --- beam centerline;
The beam 3 --- "edge";
A --- when the radar antenna is not just caused by the horizontal scanning an object altitude limit point of occlusion;
--- C under point along the radar antenna port;
O --- radar antenna center point.
Schematic elevation height restricted zone within the transitional Figure B.2
B.2 calculated radar antenna radiation in the far field region headroom Protection
B.2.1 far-field region isolated obstacles limit the height above sea level calculation method
In the far field region below the radar antenna beam along the reference line clearance environmental protection, limiting the maximum elevation point A in accordance with the obstacle
Figure B.3 formula (B.3) Calculated.
h3 = h1 (D/2) × cosφ [d (D/2) × sinφ] × tan (φ-θ/2 β), d > 2D2/λ (B.3)
Where.
H3 --- altitude radar antenna to limit occlusions elevation scan margin value β highest obstacle, in meters (m);
Point along the altitude h1 of the radar antenna port --- in meters (m);
D --- radar antenna diameter, in meters (m);
D --- the radar antenna port in the point to the horizontal distance of the highest point of the obstacle, in meters (m);
--- obstacle beta] corresponding to the highest point of elevation occlusion tolerance value, in degrees ([deg.]);
[Phi] --- traffic mode radar minimum operational elevation in degrees ([deg.]);
--- radar antenna beam width [theta], in degrees (°).
Wherein the blocking angle tolerance value in Table C.1.
Description.
1 --- beam centerline;
Under 2 --- beam edge;
--- C under point along the radar antenna port;
O --- radar antenna center point;
D --- the radar antenna port in the point to the horizontal distance from point A the highest obstacle.
B.3 highly schematic elevation view of the far-field region isolated obstacle limitation
B.2.2 far-field region isolated obstacle limitation azimuth width calculation method
In the far field antenna centerline Environmental baseline clearance radar, a radar far field direction orientation of the isolation barrier limits the width
According to FIG B.4 formula (B.4) Calculated.
b = 2 × d1 × tan (Ψ/2) (B.4)
Where.
B --- blocking position limits the width of the radar beam isolated obstacle, in meters (m);
--- D1 obstacle arbitrary point corresponding to the obstacle shielding azimuth angle (in the center of the radar antenna as a central angle) of the chord to the point
From the center of the radar antenna, in meters (m);
Occlusion azimuth tolerance value [Psi] --- obstacle in degrees (°).
Wherein the blocking angle tolerance value in Table C.1.
Description.
1 --- horizontal center of the antenna;
O --- radar antenna center point;
A, B --- two far-field region isolated obstacle edge points;
C --- radar antenna beam center line and the point of tangency isolated obstacles at the edge of the horizontal scanning, and the point O at the same elevation;
D --- radar antenna center point to the intersection of the vertical line AB connection;
--- ︱AB︱ limit position blocking the radar beam width of an isolated obstacle, i.e. when a radar antenna elevation scan at the center of the antenna from the radar to isolate
Obstacle scanning direction viewed transverse the maximum distance allowable level, AB = 2 × OD × tan (∠AOB/2);
--- azimuth angle ∠ AOB obstacle blocking tolerance value;
Blocking elevation tolerance value ∠BOC --- obstacle.
Figure B.4 isolated azimuth far field limits the width schematic obstacle
Appendix C
(Normative)
Obstructions limit capacity calculation method of the angle
C.1 calculate the radar echo power loss caused by obstructions
In the case where the same radar range, the radar echo intensity when a loss when a group of formula (C.1).
10lg
p '=
a (C.1)
Where.
P --- radar beam is not blocked when an obstacle echo reception power, in watts (W is);
p '--- beam is blocked by the obstacle received radar echo power in watts (W).
Radar echo power loss rate (p-p ')/p.
According to 5.1.1, the radar echo intensity loss takes a maximum value a = 1dB, calculated according to the formula (C.1) obtained radar echo power loss was 21%.
Total power (before blocking) of the radar radiation is calculated C.2
In practical engineering, the power density within the weather radar antenna Mainlobe (3dB) approximates a Gaussian function curve, a Gaussian distribution
Function is.
Φ (x) = ∫
- ¥
2π
e-
θ2
2dθ
Energy main lobe antenna pattern by ∫
θ1
-θ1
2π
e-
θ2
2dθ calculated, wherein (-θ1, θ1) of the antenna's main beam, the main beam deviates from the lower edge
Angle axis.
From the "standard normal distribution function value table", found
-4
2π
e-
x2
2dx = 1
The 3dB beamwidth is defined, when the power density is reduced to half the maximum value (half power point),
2π
e-
x21
2 =
2 ×
2π
e-
x2
x = 0
2 ×
2π
Solve for x1 = 1.18.
Check the "standard normal distribution function table of values" was
P (x≤1.18) = 0.881
Then P (x > 1.18) = 0.119.
Total power radar radiation (before blocking) is.
P (-1.18≤x≤1.18) = 1-2 × 0.119 = 0.762
C.3 isolated obstructions angle calculating tolerance value
When obstructions caused radar radiation power loss was 21%, effective radiated power of 79% of the total radiated power; For simplicity,
Consider only one way obstructions caused radar radiation power loss, the power loss of 0.762 × 21% = 0.16.
P (x≤x2) = 0.881-0.762 × 21% = 0.721
Now "function of the standard normal distribution table of values" de x2 = 0.59.
The antenna pattern and the density of the Gaussian probability function correspondence relationship may be of formula (C.2).
θ2
θ1 =
x2
x1 =
0.59
1.18 =
(C.2)
Where.
--- theta] 1 at the half power point of the edges from the main beam axis angle (equal to the half value width of the beam) in degrees ([deg.]);
After blocking the beam edge theta] 2 --- main beam axis deviation angle, in degrees (°).
Counting from the edge of the radar beam shielding angle tolerance value Δθ = θ1-θ2.
By the formula (C.2) found Δθ = 0.5θ1, this formula applies to elevation and azimuth.
C.4 under typical weather radar beamwidth isolated obstructions azimuth, elevation tolerance value
When the antenna beamwidth of 0.5 °, θ1 = 0.25 °, Δθ = 0.125 °.
When the antenna beamwidth of 1.0 °, θ1 = 0.5 °, Δθ = 0.25 °.
When the antenna beamwidth of 1.5 °, θ1 = 0.75 °, Δθ = 0.375 °.
Isolated obstructions typical weather radar azimuth beam width, the pitch angle margin value in Table C.1.
Table C.1 isolated tolerance value obstructions angle in degrees
Weather radar beam elevation width tolerance value obstructions isolated isolated obstructions azimuth tolerance value
0.5 0.125 0.125
1.0 0.25 0.25
1.5 0.375 0.375
twenty one
Appendix D
(Informative)
Calculation example weather radar calculation methods of the various sources of interference tolerance value and the minimum interference voltage protection pitch
D.1 interference voltage tolerance value calculation
5.1.2 The resulting loss of sensitivity, interference signal takes the maximum value 1dB, obtained by the radar weather equation
10lg
P'r, min
Pr, min =
1,
I.e. of formula (D.1)
P'r, min = Pr, min 0.26Pr, min (D.1)
Where.
When the radar receiver P'r, min --- interference signal power of the input signal, in units of decibel milliwatts (dBm);
Pr, radar receiver when the input signal power signals without interference --- min (equal to the minimum detectable signal power N), in units of dBm
(DBm).
P'r, min should meet the minimum detectable signal to noise ratio requirements, i.e. P'r, min = IN, where I is the interference power, then I = 0.26N.
The minimum interference power sources of interference caused by weather radar principles, a voltage corresponding to the interference tolerance value Ujf, max is
Ujf, max = 0.51Unf
Wherein, when no Unf interference signal equivalent to the system noise rms voltage receiver input, in units of microvolts (μV).
By the noise power to noise temperature relationship Pn =
U2n
R = kTBn
It can be derived Unf formula, see formula (D.2).
Unf = kTBnR (D.2)
Where.
K --- Boltzmann constant in Joules per Kelvin (J/K);
--- T system noise temperature, in Kelvin (K);
--- BN equivalent noise bandwidth of the receiver unit of megahertz (MHz);
--- R & lt receiver input impedance, ohms (Ω).
Seen from the formula (D.2) is calculated, 5.3GHz ~ 5.7GHz, 9.3GHz ~ 9.7GHz input of the receiver and the equivalent noise voltage UCnf UXnf
Respectively 0.86μV, 0.88μV. 13618-1992,2.7GHz ~ 3.0GHz by the receiver input noise voltage USnf equivalent to GB
0.85μV.
The minimum pitch calculation example D.2 Protection
To high voltage overhead transmission lines, substations, for example, by the GB 13618-1992 Annex B of formula (B.2) may be obtained of formula (D.3) and formula (D.4).
ESjq, max = USjf, max 20lgfS-G-10lgZ ΔEgp L-9.8 (D.3)
ECjq, max = UCjf, max 20lgfC-G-10lgZ ΔEgp L-9.8 (D.4)
Where.
ESjq, max --- S-band quasi-peak field strength of interference tolerance value in decibels microvolts per meter (dB · μV/m);
ECjq, max quasi-peak --- C-band interference field strength tolerance value in decibels microvolts per meter (dB · μV/m);
USjf, max --- S-band interference voltage tolerance value, microvolt units of decibels (dB · μV);
UCjf, max --- C-band interference voltage tolerance value, microvolt units of decibels (dB · μV);
fS --- S-band weather radar typical operating frequency in megahertz (MHz);
The typical operating frequency fC --- C-band weather radar, in units of megahertz (MHz);
G --- radar antenna gain in decibels (dB);
The Z --- radar receiver input impedance in ohms ([Omega]);
The difference between the strong and the peak field strength in decibels ΔEgp --- quasi-peak field in decibels (dB);
L --- radar antenna system loss, in decibels (dB).
Since Specifications G C-band and S-band weather radar, L, Z similar, and the two bands ΔEgp homologous to probe the environment in accordance with the best protection
Protection requirements, taking fS = ...
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