Path: Link/LinkDesign
% Performs a link budget for a satellite.
You can either enter the elevation (horizon) angle or enter the latitude,
longitude and altitude of the ground station and the earth-fixed
satellite position vector. You can also either enter the ground station
G/T or ground station antenna, noise temperature and losses.
If you want to compute rain losses you must enter the ground station
information and the climate zone. See LossPrecipitation.m for more details.
Important outputs are:
C/N is the carrier to noise ratio for the desired bandwidth
C/No is the carrier to noise ratio
EIRP is the Equivalent Isotropic Radiated Power for the transmitter
which is the figure of merit for a transmitter
Eb/No is similar to C/N only it is for the input bitrate
Required Eb/No is an input and based on the specificiation of your
communications system. LinkBudget computes the bit error rate which
should be low if you have some margin over the required Eb/No.
All inputs and outputs are in data structures.
If the optio0nal fileName is entered it will generate a latex table in
a file fileName.tex that can be \input(fileName.tex) into any latex
document.
Type LinkBudget for a demo.
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Form:
dIn = LinkBudget; % data structure
LinkBudget; % demo
dOut = LinkBudget( dIn, fileName )
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Inputs
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dIn (.) Input data structure
.transmitterPower (1,1) Transmit power (W)
.feedLoss (1,1) Feed loss (dB)
.transmitAntennaDiameter (1,1) Diameter (m)
.transmitAntennaEff (1,1) Aperture efficiency
.transmitAntennaType (1,:) 'circular aperture' or 'dipole'
.pathLength (1,1) Range (km)
.frequency (1,1) Frequency (GHz)
.requiredEbOverNo (1,1) Required Eb/No (dB)
.channelBandwidth (1,1) Bandwidth (MHz)
.bitRate (1,1) Bit rate (Mbits/s)
.fIllumination (1,1) Illumination angle (deg)
.pointingError (1,1) Pointing error (deg)
.psi (1,1) Polarization angle error (deg)
.elevationAngle (1,1) Elevation from ground plane (deg)
.modulation (1,:) Modulation type, see BEP.m
Either enter this or the receive antenna gain and temperature:
.receiveSystemGT (1,1) G/T for receiver
Or these:
.tAttenuatorAmbient (1,1) Ambient attenuator
temperature (deg-K)
.lossAttenuator (1,1) Attenuator loss (dB)
.tGround (1,1) Ground noise temperature (deg-K)
.feedLossGround (1,1) Feed loss (dB)
.tAttenuatorAmbient (1,1) Ambient temperature (deg-K)
For the receive antenna gain use these:
.receiveAntennaDiameter (1,1) Diameter (m)
.receiveAntennaEff (1,1) Aperture efficiency
.receiveAntennaType (1,:) 'circular aperture' or
'dipole'
Or:
.receiveAntennaGain (1,1) Gain (dB)
Optional Fields for rain losses:
.climateZone (1,1) Letter for zone A-H
.precipitationFract (1,1) Time with rain
.latitude (1,1) Station latitude (deg)
.longitude (1,1) Station longitude (deg)
.altitude (1,1) Station altitude (deg)
.rEF (3,1) EF position (km)
fileName (1,:) Filename for .tex file
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Outputs
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dOut (.)
.transmitterPower (1,1) Power (W)
.feedLoss (1,1) Feeder loss (dB)
.pathLoss (1,1) Free space loss along path (dB)
.frequency (1,1) Frequency (GHz)
.pathLength (1,1) Path length (km)
.antennaGain (1,1) Transmit antenna gain (dB)
.EIRP (1,1) Equivalent Isotropic Radiated
Power (dB/K)
.requiredEbOverNo (1,1) Received Eb/No (dB)
.channelBandwidth (1,1) Bandwidth (dB-Hz)
.bitRate (1,1) Bit Rate (dB-Mb/s)
.boltzmannConstant (1,1) Boltzmann's Constant (dB)
.absorptionLoss (1,1) Loss from atmosphere gas (dB)
.polarizationLoss (1,1) Loss form polarization mismatch (dB)
.rainLoss (1,1) Loss from rain (dB)
.receiveSystemGT (1,1) G/T (dB)
.pointingLoss (1,1) Loss (dB)
.receivedPower (1,1) Power (dBW)
.receivedCNo (1,1) C/No (dB-Hz)
.receivedCN (1,1) C/N (dB-Hz)
.receivedEbNo (1,1) Received Eb/No (dB)
.margin (1,1) Link margin (dB)
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See also: LossPrecipitation, BEP
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AerospaceUtils: Coord/HorizonAngle AerospaceUtils: Coord/LatLonAltToEF Link: LinkUtilities/BEP Link: LinkUtilities/DBSignal Link: RF/AntennaGain Link: RF/Beamwidth3dB Link: RF/LossAtmosphericGas Link: RF/LossDepointing Link: RF/LossFreeSpace Link: RF/LossPolarization Link: RF/LossPrecipitation Link: RF/TAntennaGround Link: RF/TAttenuator Link: RF/TReceiver Link: RF/TSky Common: General/CreateLatexTable
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