Satcomms A (Autumn 2002) Part 2 - University of Surrey

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Satellite Communications ALink planning budgetting Professor Barry G Evans Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 1 Link budget system planning.
Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 2 Mobile SystemAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 3 Performance i QoS b e r .
10 4 if speech 10 6 10 8 data extra coding ii Availability Channel conditionsAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 4.
Basic TransmissionAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 5 Carrier Transmission Budget Antenna Gain The antenna gain is defined as the ratio of the power per unit solid angle received radiated by.
the antenna in a given direction to the power per unit solid angle received radiated by anisotropic antenna supplied with the same power Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 6 Basic TransmissionAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 7.
Basic TransmissionAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 8 Antenna radiation patternAntenna radiation pattern gain variations as a function of the angle relative to boresight.
Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 9 Transmitted power in a given directionAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 10 Predicted coverage areas for theHOTBIRD satellites.
a Superbeam b Widebeam courtesy of EUTELSAT Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 11 Effective isotropically radiated power.
Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 12 Exercise 1 Carrier Transmission Power fed to antenna PT 10W Antenna gain at boresight GTmax 40dB Distance R 36000km earth to geostationary satellite.
Calculate Transmitter EIRP in dB W Flux density at receiver in dB W m2 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 13 Down Path.
Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 14 GEO GeometryAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 15 Earth station from the geostationary orbit Satellite.
Height h above the equator Sub satellite point longitude S Earth station Latitude E longitude E Relative longitude satellite E S ES.
Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 16 Exercise 2 Carrier Transmission Uplink frequency 14GHz Eart station Power fed to the antenna PT 100W.
Antenna diameter D 4 efficiency 0 6 Location Bercenay France Latitude 48 13 07 N Longitude 03 53 13 E Satellite.
Receiving antenna gain at boresight GRmax 40dB Location 7 E EUTELSAT 1 F2 Calculate EIRP of earth station Free space loss.
Received powerAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 17 Noise in an Earth StationTa Tf TD L BASEBANDLNA IPA DEMOD QoS.
TLNA TIPA Lo BER Noise comes from Ta picked up by antenna from outside effective noise Tf lossy feeder TLNA TIPA amplifiers in receiver chain.
TD C down converter Refer all noise to a reference plane into the LNAAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 18 Noise in a Payload Noise comes from .
Antenna received noise earth galaxy Feeder lossy noise nb 290K Equipment noise amps D C etc added in same way as for earthAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 19 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 20.
Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 21 Noise Characterisation 1 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 22 Noise Characterisation 2 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 23.
Noise contribution of an attenuatorAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 24 Earth station system G Tand noise temp Ta Tf TLNA.
LdB LNA IPA D Cg LNA LD Cg LNA xg IPA 1 Tfl TIPA T DC.
Ts Ta 1 Tf TLNA l gLNA gLNA x gIPALdB 10log l 1GdB 10log g Gain of antenna at reference Ga L dB.
G Ga L 10Log Ts dB KAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 25 Earth station antenna noise temperatureExamples clear sky conditions Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 26.
Exercise 3 Noise Contribution Operating frequency 12 GHz LNA TLNA 150K GLNA 50dB MIXER TMX 850K GMX 10dB IF AMP TIF 400K GIF 30dB.
Calculate Receiver effective input noise temperature TR Receiver noise figureAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 27 Exercise 4 G T of C band earth.
Dish 15m n 70 Feeder Ta 30K LNA IPA D C Tf 290K Loss f 0 5dB TLNA 35K.
GLNA 30dB FIPA 3dB GIPA 20dB TD C 1000K Loss D C 10dB.
Calculate the earth station G T What are the advantages of trading off dish size and LNA temp Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 28 Propagation Effects to be considered .
Radio noise Ionospheric effects Absorption Total electron content effects group delay refraction polarisation rotation .
Scintillation Tropospheric effects Attenuation by rain Depolarisation Refraction effects.
Shadowing and multipath effectsAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 29 Clear Sky Noise Temperature Any ATTENUATION process which involves energyabsorption is associated with THERMAL NOISE.
GENERATION from the medium Absorption by atmospheric gases is frequency dependent hence clear sky noise temperature exhibits similar variationswith frequencyAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 30.
Attenuation by atmospheric gases See CCIR Rep 719 for a detailed description of practicaltechniques of calculation for LAG The following curvedisplays AAG E versus frequency E is the elevation angle Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 31.
Noise temperature of the sunAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 32 Ionospheric effectsAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 33 Attenuation due to rain etc .
CloudsAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 34 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 35 References for calculationmethodology.
Course notes or chapter 8 of the book ITU R PN 618 3 splant path rain inducedattenuation and depolarisation and scintillatin available from lending libraries or ITU Geneva Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 36.
Attenuation due to precipitation and cloudsRelevant techniques described in CCIR see rep 563 564 721 723 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 37 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 38 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 39.
Maps of rainfall contours 1 3 Contours of RAINFALL RATER mm h exceeded for0 01 OF AN AVERAGEAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 40.
Maps of rainfall contours 2 3 Contours of RAINFALL RATER mm h exceeded for0 01 OF AN AVERAGEAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 41.
Maps of rainfall contours 3 3 Contours of RAINFALL RATER mm h exceeded for0 01 OF AN AVERAGEAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 42.
Nomogram for determination ofspecific attenuation with circular polarization use the arithmetic mean of attenuation withhorizontal and vertical polarizationAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 43.
Typical values of rain attenuation30 20 GHz systems face a problem especially in tropical regions whererainfall rate is very high during small percentage of time Performance objective must be achieved when rain occurs The link willprobably be over dimensioned during most of the time margin .
Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 44 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 45 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 46 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 47 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 48.
DEPOLARISATION Rain and ice cause this due to shape of Need to know shape and orientation of particles Linear and circular POLN different Circular POLN is worst case.
Can form a model linking depolarisation XPD and attenuationAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 49 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 50 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 51.
Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 52 XPD STATISTICSAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 53 Raininduced XPD circular polarisation for 1 worsth month .
CO POLAR ATTENUATIONAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 54 Other tropospheric effects Dry snow ok little effect Wet snow as bad as rain.
Problem if snow builds up on antenna Atmospheric absorption Gas and particle absorption worse at lowelevation angles Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 55.
Noise Contribution Budget Satellite Antenna Noise Temperature 1 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 56 Noise Contribution Budget Satellite Antenna Noise Temperature 2 .
Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 57 Influence of RainAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 58Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 59 Exercise 5 a Carrier Transmission.
Ta 50K 0 9 Tf 290k Pointing loss 0 7dB Atmospheric loss 0 3dB Rain loss 3dB for 99 lime Rain temp 275K.
Calculate the G T of the earth station under worst weatherconditions Calculate the down link C No Calculate the down link C N if the link bandwidth is 100KHz Complete the link budget sheet.
Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 60 Exercise 5 b Link budget sheet Link budget sheet DownlinkSatellite EIRP dBWPointing loss dB.
Atmospheric loss dBRain loss 99 dBFree space loss dBGain E S dBDownlink carrier dBW.
E S noise temp dB KE S G T dB KBoltzmann constant 228 6 dBW Hz KDownlink noise dBW Hzdensity NOD .
C NOD dB HzAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 61 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 62 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 63 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 64.
Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 65 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 66 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 67 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 68 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 69.
Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 70 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 71 Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 72 DOWNLINKAutumn2004 University of Surrey SatComms A part 3 B G Evans 3 73.
Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 74Autumn2004 University of Surrey SatComms A part 3 B G Evans 3 75 Exercise 6 Up link Ku band uplink 14GHz SAT eirps Dish size 5m 0 65.
Distance to satellite 38 000km Uplink atmospheric loss 0 3dB Uplink pointing loss 0 7dB Uplink rain loss 3dB Tx e s w g feed loss 3dB.
Satellite Rx antenna gain 26dBi from Tx e s Satellite Tx antenna gain 25dBi at boresight Rx earth station AR 2dB Satellite Tpdr gain 120dB.
EEM.scmA Satellite Communications A Part 3 Link planning / budgetting-Professor Barry G Evans-Link budget & system planning Mobile System Performance (i) QoS – b.e.r. 10-4 if speech 10-6 – 10-8 data (extra coding) (ii) Availability 95% Channel conditions Basic Transmission Carrier Transmission Budget -Antenna Gain- The antenna gain is defined as the ratio of the power per unit solid angle ...

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