sigstrength

Signal strength due to transmitter

Syntax

ss = sigstrength(rx,tx)

ss = sigstrength(rx,tx,propmodel)

ss = sigstrength(___,Name,Value)

Description

ss = sigstrength(rx,tx) returns the signal strength at the receiver site due to the transmitter site.

ss = sigstrength(rx,tx,propmodel) returns the signal strength at the receiver site using the specified propagation model. Specifying propagation model is same as specifying the 'PropagationModel' name-value pair.

ss = sigstrength(___,Name,Value) returns the signal strength using additional options specified by Name,Value pairs and either of the previous syntaxes.

Examples

Received Power and Link Margin at Receiver

Create a transmitter site.

tx = txsite('Name','Fenway Park', ...
        'Latitude', 42.3467, ...
        'Longitude', -71.0972);

Create a receiver site with sensitivity defined (in dBm).

 rx = rxsite('Name','Bunker Hill Monument', ...
        'Latitude', 42.3763, ...
        'Longitude', -71.0611, ...
        'ReceiverSensitivity', -90);

Calculate the received power and link margin. Link margin is the difference between the receiver's sensitivity and the received power.

ss = sigstrength(rx,tx)

ss = -71.1414

margin = abs(rx.ReceiverSensitivity - ss)

margin = 18.8586

Signal Strength Using Ray Tracing Image Method Propagation Model

Launch Site Viewer with buildings in Chicago.

viewer = siteviewer("Buildings","chicago.osm");

Create transmitter site on a building.

tx = txsite('Latitude',41.8800, ...
    'Longitude',-87.6295, ...
    'TransmitterFrequency',2.5e9);

Create receiver site near another building.

rx = rxsite('Latitude',41.881352, ...
    'Longitude',-87.629771, ...
    'AntennaHeight',30);

Compute signal strength using ray tracing propagation model and default single-reflection analysis.

pm = propagationModel("raytracing-image-method");
ssOneReflection = sigstrength(rx,tx,pm)

ssOneReflection = -55.2839

Compute signal strength with analysis up to two reflections, where total received power is the cumulative power of all propagation paths

pm.MaxNumReflections = 2;
ssTwoReflections = sigstrength(rx,tx,pm)

ssTwoReflections = -53.1827

Observe effect of material by replacing default concrete material with perfect reflector.

pm.BuildingsMaterial = 'perfect-reflector';
ssPerfect = sigstrength(rx,tx,pm)

ssPerfect = -42.0872

Plot propagation paths.

raytrace(tx, rx, pm) 

Input Arguments

rx — Receiver site

rxsite object | array of rxsite objects

Receiver site, specified as a rxsite object. You can use array inputs to specify multiple sites.

tx — Transmitter site

txsite object | array of txsite objects

Transmitter site, specified as a txsite object. You can use array inputs to specify multiple sites.

propmodel — Propagation model

character vector | string

Propagation model, specified as a character vector or string. You can also use the name-value pair 'PropagationModel' to specify this parameter. You can also use the propagationModel function to define this input.

Data Types: char | string

Name-Value Pair Arguments

Specify optional comma-separated pairs of Name,Value arguments. Name is the argument name and Value is the corresponding value. Name must appear inside quotes. You can specify several name and value pair arguments in any order as Name1,Value1,...,NameN,ValueN.

Example: 'Type','power'

'Type' — Type of signal strength to compute

'power' (default) | 'efield'

Type of signal strength to compute, specified as the comma-separated pair consisting of 'Type and 'power' or 'efield'.

When type is 'power', signal strength is expressed in power units (dBm) of the signal at the mobile receiver input. When type is 'efield', signal strength is expressed in electric field strength units (dBμV/m) of signal wave incident on the antenna.

Data Types: char | string

'PropagationModel' — Propagation model to use for path loss calculations

'longley-rice' (default) | 'freespace' | 'close-in' | 'rain' | 'gas' | 'fog' | 'raytracing-image-method' | propagation model object

Propagation model to use for the path loss calculations, specified as the comma-separated pair consisting of 'PropagationModel' and 'freespace', 'close-in', 'rain', 'gas', 'fog', 'longley-rice', 'raytracing-image-method', or as an object created using the propagationModel function. The default propagation model is 'longeley-rice' when terrain is enabled and 'freespace' when terrain is disabled.

Data Types: char

'Map' — Map for visualization or surface data

siteviewer object | terrain name

Map for visualization or surface data, specified as the comma-separated pair consisting of 'Map and a siteviewer object or a terrain name. A terrain name may be specified if the function is called with an output argument. Valid terrain names are 'none', 'gmted2010', or the name of the custom terrain data added using addCustomTerrain. The default value is the current Site Viewer. If no Site Viewer is open, the default value is a new Site Viewer or else 'gmted2010' if the function is called with an output argument.

Data Types: char | string

Output Arguments

ss — Signal strength

M-by-N array

Signal strength, returned as M-by-N array in dBm. M is the number of TX sites and N is the number of RX sites.