propagationData

Create RF propagation data from measurements

Description

Use the propagationData object to import and visualize geolocated propagation data. The measurement data can be path loss data, signal strength measurements, signal-to-noise-ratio (SNR) data, or cellular information.

Creation

Syntax

pd = propagationData(filename)

pd = propagationData(table)

pd = propagationData(latitude,longitude,varname,varvalue)

pd = propagationData(___,Name,Value)

Description

pd = propagationData(filename) creates a propagation data object by reading data from a file specified by filename.

pd = propagationData(table) creates a propagation data container object from a table object specified by table.

pd = propagationData(latitude,longitude,varname,varvalue) creates a propagation data container object using latitude and longitude coordinates with data specified using varname and varvalue.

pd = propagationData(___,Name,Value) sets properties using one or more name-value pairs. Enclose each property name in quotes.

Input Arguments

filename — Name of file containing propagation data

character vector | string scalar

Name of the file containing propagation data, specified as a character vector or a string scalar. The file must be in the current directory, in a directory on the MATLAB path, or be specified using a full or relative path. The file must be compatible with the readtable function. Call the readtable function if customized parameters are required to import the file and then pass the table object to the propagationData object.

Propagation data in the file must have one variable corresponding to the latitude values, one variable corresponding to longitude values, and at least one variable containing numeric data.

Data Types: string | char

table — Table containing propagation data

table object

Table containing propagation data, specified as a table object.

Propagation data in the file must have one variable corresponding to the latitude values, one variable corresponding to longitude values, and at least one variable containing numeric data.

Data Types: table

latitude — Latitude coordinate values

vector

Latitude coordinate values, specified as a vector in decimal degrees with reference to Earth's ellipsoid model WGS-84. The latitude coordinates must be in the range [-90 90].

Data Types: double

longitude — Longitude coordinate values

vector

Longitude coordinate values, specified as a vector in decimal degrees with reference to earth's ellipsoid. model WGS-84.

Data Types: double

varname — Variable name

character vector | string scalar

Variable name, specified as a character vector or a string scalar. This variable name must correspond to the variable with numeric data other than latitude or longitude. The variable name and the corresponding values are stored as a column in the Data property table object.

Data Types: string | char

varvalue — Variable values

numeric vector

Variable values, specified as a numeric vector. The numeric vectors must be the same size as latitude and longitude. The variable name and corresponding values are stored as a column in the Data property table object.

Data Types: double

Output Arguments

pd — Propagation data

propagationData object

Propagation data, returned as a propagationData object.

Properties

Name — Propagation data name

'Propagation Data' (default) | character vector | string scalar

Propagation data name, specified as a character vector or string scalar.

Example: 'Name','propdata'

Example: pd.Name = 'propdata'

Data Types: char | string

Data — Propagation data table

scalar table object

This property is read-only.

Propagation data table, specified as a scalar table object containing a column corresponding to latitude coordinates, a column corresponding to longitude coordinates, and one or more columns corresponding to associated propagation data.

Data Types: table

DataVariableName — Name of data variable to plot

character vector | string scalar

Name of the data variable to plot, specified as a character vector or string scalar corresponding to a variable name in the Data table used to create propagation data container object. The variable name must correspond to a variable with numeric data and cannot correspond to the latitude or longitude variables. The default value for this property is the name of the first numeric data variable name in the Data table that is not a latitude or longitude variable.

Data Types: char | string

Object Functions

plot	Display RF propagation data in Site Viewer
contour	Display contour map of RF propagation data in Site Viewer
location	Coordinates of RF propagation data
getDataVariable	Get data variable values
interp	Interpolate RF propagation data

Examples

Compute Signal Strength Data in Urban Environment

Launch Site Viewer with basemaps and building files for Manhattan. For more information about the osm file, see [1].

viewer = siteviewer("Basemap","streets_dark",...
        "Buildings","manhattan.osm");

Show a transmitter site on a building.

tx = txsite("Latitude",40.7107,...
        "Longitude",-74.0114,...
        "AntennaHeight",80);
show(tx)

Create receiver sites along nearby streets.

latitude = [linspace(40.7088, 40.71416, 50), ...
        linspace(40.71416, 40.715505, 25), ...
        linspace(40.715505, 40.7133, 25), ...
        linspace(40.7133, 40.7143, 25)]';
longitude = [linspace(-74.0108, -74.00627, 50), ...
        linspace(-74.00627 ,-74.0092, 25), ...
        linspace(-74.0092, -74.0110, 25), ...
        linspace(-74.0110, -74.0132, 25)]';
rxs = rxsite("Latitude", latitude, "Longitude", longitude);

Compute signal strength at each receiver location.

signalStrength = sigstrength(rxs, tx)';

Create a propagationData object to hold computed signal strength data.

tbl = table(latitude, longitude, signalStrength);
pd = propagationData(tbl);

Plot the signal strength data on a map as colored points.

legendTitle = "Signal" + newline + "Strength" + newline + "(dB)";
plot(pd, "LegendTitle", legendTitle, "Colormap", parula);

Appendix

[1] The osm file is downloaded from https://www.openstreetmap.org, which provides access to crowd-sourced map data all over the world. The data is licensed under the Open Data Commons Open Database License (ODbL), https://opendatacommons.org/licenses/odbl/.

Capacity Map Using SINR Data

Define names and locations of sites around Boston.

names = ["Fenway Park","Faneuil Hall","Bunker Hill Monument"];
lats = [42.3467,42.3598,42.3763];
lons = [-71.0972,-71.0545,-71.0611];

Create an array of transmitter sites.

txs = txsite("Name",names,...
       "Latitude",lats,...
       "Longitude",lons, ...
       "TransmitterFrequency",2.5e9);
show(txs)

Create a signal-to-interference-plus-noise-ratio (SINR) map, where signal source for each location is selected as the transmitter site with the strongest signal.

sv1 = siteviewer("Name","SINR map");
sinr(txs,"MaxRange",5000)

Return SINR propagation data.

pd = sinr(txs,"MaxRange",5000);
[sinrDb,lats,lons] = getDataVariable(pd,"SINR"); 

Compute capacity using the Shannon-Hartley theorem.

bw = 1e6; % Bandwidth is 1 MHz
sinrRatio = 10.^(sinrDb./10); % Convert from dB to power ratio
capacity = bw*log2(1+sinrRatio)/1e6; % Unit: Mbps

Create new propagation data for the capacity map and display the contour plot.

pdCapacity = propagationData(lats,lons,"Capacity",capacity);
sv2 = siteviewer("Name","Capacity map");
legendTitle = "Capacity" + newline + "(Mbps)";
contour(pdCapacity,"LegendTitle",legendTitle);

Version History

Introduced in R2020a