p618PropagationLosses

Calculate Earth-space propagation losses, cross-polarization discrimination, and sky noise temperature

Syntax

[pl,xpd,tsky] = p618PropagationLosses(p618cfg)

[pl,xpd,tsky] = p618PropagationLosses(p618cfg,Name,Value)

Description

[pl,xpd,tsky] = p618PropagationLosses(p618cfg)returns Earth-space propagation lossespl, cross-polarization discriminationxpd, and sky noise temperaturetsky, as defined in the ITU-R P.618 recommendation[1].p618cfgspecifies the P.618 configuration parameters.

This function requires MAT-files with digital maps from International Telecommunication Union (ITU) documents. If they are not available on the path, download and uncompress the data files from//www.tatmou.com/supportfiles/spc/P618/ITURDigitalMaps.tar.gzto a location on the MATLAB path.

example

[pl,xpd,tsky] = p618PropagationLosses(p618cfg,Name,Value)specifies additional options using one or more name-value pair arguments.

Examples

collapse all

Calculate Propagation Losses, Cross-Polarization Discrimination, and Sky Noise Temperature

Open Live Script

This example requires MAT-files with digital maps from ITU documents. If they are not available on the path, execute the following commands to download and unzip the MAT-files.

maps = exist('maps.mat','file'); p836 = exist('p836.mat','file'); p837 = exist('p837.mat','file'); p840 = exist('p840.mat','file'); matFiles = [maps p836 p837 p840];if~all(matFiles)if~exist('ITURDigitalMaps.tar.gz','file') url ='//www.tatmou.com/supportfiles/spc/P618/ITURDigitalMaps.tar.gz'; websave('ITURDigitalMaps.tar.gz',url); untar('ITURDigitalMaps.tar.gz');elseuntar('ITURDigitalMaps.tar.gz');endaddpath(cd);end

Create a default P.618 configuration object.

cfg = p618Config;

Specify the time percentage of excess for the rain attenuation per annum as 0.01 and the time percentage of excess for the total attenuation per annum as 0.001.

cfg.RainAnnualExceedance = 0.01; cfg.TotalAnnualExceedance = 0.001;

Calculate the propagation losses, cross-polarization discrimination, and sky noise temperature.

[pl,xpd,tsky] = p618PropagationLosses(cfg)

pl =struct with fields:Ag: 0.2269 Ac: 0.4552 Ar: 6.7981 As: 0.2633 At: 15.6091

xpd = 32.8876

tsky = 267.4689

Calculate Earth-space Propagation Losses Using Name-Value Pair Arguments

Open Live Script

This example requires MAT-files with digital maps from ITU documents. If they are not available on the path, execute the following commands to download and untar the MAT-files.

maps = exist('maps.mat','file'); p836 = exist('p836.mat','file'); p837 = exist('p837.mat','file'); p840 = exist('p840.mat','file'); matFiles = [maps p836 p837 p840];if~all(matFiles)if~exist('ITURDigitalMaps.tar.gz','file') url ='//www.tatmou.com/supportfiles/spc/P618/ITURDigitalMaps.tar.gz'; websave('ITURDigitalMaps.tar.gz',url); untar('ITURDigitalMaps.tar.gz');elseuntar('ITURDigitalMaps.tar.gz');endaddpath(cd);end

Create a P.618 configuration object with a signal frequency of 20 GHz.

cfg = p618Config('Frequency',20e9);

Specify the surface water vapor density as 2.8 $\frac{g}{m^{3}}$ , the total columnar content of the cloud liquid water as 1.4 $\frac{kg}{m^{2}}$ , and the median value of the wet surface refractivity as 1.2. Set the earth station height as 0.5 km. Calculate the Earth-space propagation losses.

pl = p618PropagationLosses(cfg,'StationHeight',0.5,...'WaterVaporDensity',2.8,...'TotalColumnarContent',1.4,...'WetSurfaceRefractivity',1.2)

pl =struct with fields:Ag: 0.8649 Ac: 1.0987 Ar: 0.8907 As: 0.1372 At: 2.8590

Calculate Propagation Losses in Light Rainfall

Open Live Script

This example requires MAT-files with digital maps from ITU documents. If they are not available on the path, execute the following commands to download and unzip the MAT-files.

maps = exist('maps.mat','file'); p836 = exist('p836.mat','file'); p837 = exist('p837.mat','file'); p840 = exist('p840.mat','file'); matFiles = [maps p836 p837 p840];if~all(matFiles)if~exist('ITURDigitalMaps.tar.gz','file') url ='//www.tatmou.com/supportfiles/spc/P618/ITURDigitalMaps.tar.gz'; websave('ITURDigitalMaps.tar.gz',url); untar('ITURDigitalMaps.tar.gz');elseuntar('ITURDigitalMaps.tar.gz');endaddpath(cd);end

Create a P.618 configuration object that occupies a signal frequency of 20 GHz.

cfg = p618Config('Frequency',20e9);

Calculate the propagation losses in a light rainfall of 1 mm/hr with an earth station height of 0.75 km.

pl = p618PropagationLosses(cfg,'RainRate',1,'StationHeight',0.75)

pl =struct with fields:Ag: 0.7996 Ac: 0.8793 Ar: 0.0177 As: 0.3187 At: 1.7514

Input Arguments

collapse all

`p618cfg`—P.618 configuration
p618Config object

P.618 configuration required for the calculation of the propagation losses, cross-polarization discrimination, and sky noise temperature, specified as ap618Configobject.

Name-Value Arguments

Specify optional pairs of arguments asName1=Value1,...,NameN=ValueN, whereNameis the argument name andValueis the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Before R2021a, use commas to separate each name and value, and encloseNamein quotes.

Example:'StationHeight',1.5specifies the earth station height as 1.5 km.

`StationHeight`—Height of earth station
nonnegative scalar

Height of the earth station above the mean sea level in km, specified as the comma-separated pair consisting of 'StationHeight' and a nonnegative scalar. The maximum supported value is 100. If the local data is not available as an input, the function uses the digital maps provided in ITU-R P.1511 section 1, Annex 1[3]to obtain the station height value.