Propagation Effects Handbook for Satellite Systems - DESCANSO ...

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Table 6.3-2. Rain Rates Exceeded for 0.01% of the Time Climate ABCDEFG HJKLMNP Rate 8 12 15 19 22 28 30 32 35 42 60 63 95 145 SteR 2 Determine the effective rain height, hr, from; hr = 4.0 = 4.0 - 0.075 ( +- 361 +: j6~< 36° (6.3-11) where $is the latitude of the ground station, in degrees N or S. W Calculate the slant path length? h~ horizontal Projection LG, and reduction factor, rpr from: For @ ~ 5°, = (h r - hO)/sin (@) (6.3-12) LG = L~ COS (@) (6.3-13) rp (6.3-14) 1 + 0.~45LG where @ is the elevation angle to the satellite~ in degrees~ and ho is the height above mean sea level of the ground terminal location~ in km. (For elevation angles less then 5°~ see Section 306). Step 4 Obtain the specific attenuation coefficients~ K anda, at the frequency and polarization angle of interest from Table 6.3-3. For frequencies not on the table, use logarithmic interpolation for K and linear interpolation for a. For polarization tilt angles other than linear horizontal or vertical, use the relationships on Figure 6.3-6, Step 4, to obtain K and a. Step 5 Calculate the attenuation exceeded lar 0.01% of an average year from; Ao,o1 = K Ro.01~ LS r p (6.3-15) 6-34
Step 6 Calculate the attenuation exceeded for other percentage values of an average year from: AP = 0012 AOCO1 p-(0.546 + 0.043 109 P] (6.3-16) This relationship is valid for annual percentages from 0.001% to 1.0%. 6.3.2.4 Sample Calculation for the CCIR Model In this section the CCIR model is applied to a specific ground terminal case. Consider a terminal located at Greenbelt, MD., at a latitude of 38°N, and elevation above sea level of 0.2 km. The characteristics of the link are as follows: Frequency: 11.7 GHz . Elevation Angle: 29° Polarization: Circular Step 1 Figure 6.3-7 indicates that the terminal is in climate zone K, with a corresponding RO,Ol f 42 mm/h (Table 6.3-2). Step 2 The effective rain height, from Eq (6.3-11), is hr = 4.0 - 0.075(38 - 36) = 3.85 Step 3 ‘I’he slant path length, horizontal projection, and reduction factor are determined from Eq.’s (6.3-12, -13, -14) r@spectiv@ly: Ls = (3.85 - 0.2)(/sin(29°) = 7.53 LG = (7.53)cos(29°) = 6.58 rp = 1/[1 + (0.045)(6.58)] = o.771 6-35
Page 1 and 2: 1 6.1 INTRODUCTION 6.1.1 purpose CH
Page 3 and 4: ,s Table 6.1-1. Guide to Sample Cal
Page 5 and 6: I . . 6.1.4 Other Propagation Effec
Page 7 and 8: . . collisions at normal atmospheri
Page 9 and 10: D 1000 100 10 1 U.S. Standard Atmos
Page 11 and 12: Frequency (GHz) 10 15 20 30 40 80 1
Page 13 and 14: If PW is not available from local w
Page 15 and 16: . . The equivalent heights for oxyg
Page 17 and 18: m t TEMPERATURE rC) o 5 10 15 20 25
Page 19 and 20: 6.3 PREDICTION OF CUMULATIVE STATIS
Page 21 and 22: LSTATION LOCATION AND ELEVATION STE
Page 23 and 24: The models require the following in
Page 25 and 26: I z za E 100 g w ~ z z K 50 a) ALL
Page 27 and 28: B . . . t- I I I I I 1 11/1 - . . .
Page 29 and 30: .- . 9 s@EQ - If Z S D, compute the
Page 31 and 32: 1 0.02 0.05 0.2 0.5 4. Compute D: U
Page 33: I . ,. . ~ q 8 H v ~ 1.0 0.8 0.6 0.
Page 37 and 38: m I : STEP 1 SELECT CLIMATE ZONE FR
Page 39 and 40: 9 10.OOOO 1.0000 0,1ooo 0.0100 0.00
Page 41 and 42: 1 6.3.3 Estimates of Attenuation Gi
Page 43 and 44: ● We now proceed exactly as in th
Page 45 and 46: STEP 1 GIVEN: STATION PARAMETERS SA
Page 47 and 48: . B . . . 4. Repeat the process for
Page 49 and 50: . . ● 100 10 1.0 .1 .01 . . RAIN
Page 51 and 52: not normally available~ but empiric
Page 53 and 54: ● The intensity-duration-frequenc
Page 55 and 56: - GIVEN: STATION PARAMETERS OPERATI
Page 57 and 58: m I s 70 2(J I 10 0 a) BY SEASONS
Page 59 and 60: .“ ● change in rain rater the r
Page 61 and 62: m To x o 6 x(n wux!- (5 zawwvxw x 1
Page 63 and 64: ● ✎ ✎ ✎ 10 1 0.1 0.01 0 . -
Page 65 and 66: ● ✎ ✎ ✎ appears to be gener
Page 67 and 68: 6.4.2.3 Statistics of Microwave Eff
Page 69 and 70: ● For each hour’s observations,
Page 71 and 72: Plots of noise temperature and atte
Page 73 and 74: .- I where Lf is the fog extent~ in
Page 75 and 76: than a minute and on spatial scales
Page 77 and 78: . . . 022 = angle-of-arrival varian
Page 79 and 80: B . . Figure 6.5-2 represents the a
Page 81 and 82: - . . , 1 I t , 3 , I 1 # 1 1 aJ 0a
Page 83 and 84: I . . -. % i ! ~ * 76.00 I h 60.00
Page 85 and 86:
I where the constants are the same
Page 87 and 88:
.U . . \ Table 6.5-1. Fading Data P
Page 89 and 90:
o -5C \ A — . \ \ \ \ N- ● ●
Page 91 and 92:
I 1 \ 0,, FADE DEPTHS I 1 l.d 0.1 1
Page 93 and 94:
9 m ELEVATION ANGLE [DEGREESI ELEVA
Page 95 and 96:
Figure 6.5-12 is an example for thi
Page 97 and 98:
equal. The fade distributions resul
Page 99 and 100:
m . ANTENNA BEAMVVID~ (DEG) d o 0 w
Page 101 and 102:
. . 6.5.5.2.2 Spatial Diversity. Pa
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fluctuation power at 1 Hz is on the
Page 105 and 106:
develops (Pruppacher and Pitter-197
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.8 where: f = frequency, in GHz r =
Page 109 and 110:
B . k 11.7 26 \ QHz DATA, CTS A VPl
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\ for the 11.7 GHz CTS beacon at 50
Page 113 and 114:
● these do not correlate well wit
Page 115 and 116:
. However the XPD dependence on ele
Page 117 and 118:
-. 50 40 30 20 10 0 . T(XPD < ABCIS
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9 electrostatic fields discharge ra
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, f w m I
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. XPD 2 = XPD1 - 20 lo91~ f ~ 1 0.4
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● 3.0 14 0.6 0.3 0,1 0.0s 0.03 0.
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where, for example, for the frequen
Page 129 and 130:
L .- . ., not appear to be sufficie
Page 131 and 132:
D ‘1 may be considered to be rece
Page 133 and 134:
D - 0 m a 80 60 40 20 0 -20 \ — i
Page 135 and 136:
m I s 1 \\ I , t Frequency (GHz) Fi
Page 137 and 138:
-. Table 6.8-1. Cumulative Statisti
Page 139 and 140:
D - The propagation margin is then
Page 141 and 142:
1- * w -180 -190 -m -21 / ---+---4~
Page 143 and 144:
- . . 6.9 UPLINK NOISE IN SATELLITE
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280 260 240 220 200 180 160 140 120
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6.10 REFERENCES Ahmed, I.Y. and L.J
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● International Telecommunication
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Atmospheric Emission observations,
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8.6 and 3.2 mm Radio Waves by Cloud
Page 155 and 156:
I Strickland, J.I. (1974), “Radar
Page 157:
D Wulfsberg, K.N. (1964), “Appare
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