sigstrength

Calculate received signal strength at last node of link

Since R2022b

Syntax

PISO = sigstrength(lnk)

[PISO,PRI] = sigstrength(lnk)

[___] = sigstrength(lnk,timeIn)

[PISO,PRI,timeOut] = sigstrength(___)

Description

PISO = sigstrength(lnk) returns a history matrix of received isotropic power in dBW at the final node in each link defined in the vector, lnk. The rows of the matrix correspond to the link object in lnk and the columns correspond to the time sample.

Note

This calculation uses the standard free‑space path loss model (FSPL) when computing received power.

[PISO,PRI] = sigstrength(lnk) returns received isotropic power, PISO, and history matrix of the power at receiver input, PRI, in dBW at the final node in each link defined in the vector, lnk. The rows of the matrix correspond to the link object in lnk and the columns correspond to the time sample.

[___] = sigstrength(lnk,timeIn) returns one or both of the outputs as column vectors at the specified datetime timeIn. The elements in the vectors correspond to the links in lnk. If no time zone is specified in timeIn, the time zone is assumed to be Coordinated Universal Time (UTC).

[PISO,PRI,timeOut] = sigstrength(___) returns the received isotropic power, power at the receiver input, and the corresponding datetime in UTC.

Examples

Obtain Signal Strength of Satellite Link

This example computes the history of received isotropic power, power at receiver input, and the corresponding time samples of the satellite link.

Create a satellite scenario object.

startTime = datetime(2020,10,13,10,42,0);
stopTime = datetime(2020,10,13,10,50,0);
sampleTime = 60;                                      % seconds
sc = satelliteScenario(startTime,stopTime,sampleTime);

Add a satellite to the scenario.

semiMajorAxis = 10000000;                                          % meters
eccentricity = 0;
inclination = 0;                                                   % degrees
rightAscensionOfAscendingNode = 0;                                 % degrees
argumentOfPeriapsis = 0;                                           % degrees
trueAnomaly = 210;                                                 % degrees
sat = satellite(sc,semiMajorAxis,eccentricity,inclination, ...
    rightAscensionOfAscendingNode,argumentOfPeriapsis,trueAnomaly);

Add a transmitter to the satellite.

tx = transmitter(sat);

Add a ground station to the scenario.

latitude = 0;                             % degrees
longitude = 30;                           % degrees
gs = groundStation(sc,latitude,longitude);

Add a receiver to the ground station.

rx = receiver(gs,MountingAngles=[0; 180; 0]);

Add a link analysis to the transmitter.

lnk = link(tx,rx);

Obtain the history of received isotropic power, power at receiver input, and time samples.

[PISO,PRI,timeOut] = sigstrength(lnk)

PISO = 1×9
103 ×

   -0.2526   -0.1431   -0.1553   -0.2886   -0.5357   -0.8837   -1.3154   -1.8117   -2.3525

PRI = 1×9
103 ×

   -0.5087   -0.1292   -0.1714   -0.6337   -1.4973   -2.7289   -4.2840      -Inf      -Inf

timeOut = 1×9 datetime
   13-Oct-2020 10:42:00   13-Oct-2020 10:43:00   13-Oct-2020 10:44:00   13-Oct-2020 10:45:00   13-Oct-2020 10:46:00   13-Oct-2020 10:47:00   13-Oct-2020 10:48:00   13-Oct-2020 10:49:00   13-Oct-2020 10:50:00

Obtain Signal Strength of Satellite Link at Specified Time

This example computes the received isotropic power and the power at receiver input of the satellite link at a specified time.

Create a satellite scenario object.

startTime = datetime(2021,10,13,10,5,0);
stopTime = startTime + days(1);
sampleTime = 60;                                      % seconds
sc = satelliteScenario(startTime,stopTime,sampleTime);

Add a satellite to the scenario.

semiMajorAxis = 10000000;                                          % meters
eccentricity = 0;
inclination = 0;                                                   % degrees
rightAscensionOfAscendingNode = 0;                                 % degrees
argumentOfPeriapsis = 0;                                           % degrees
trueAnomaly = 210;                                                 % degrees
sat = satellite(sc,semiMajorAxis,eccentricity,inclination, ...
    rightAscensionOfAscendingNode,argumentOfPeriapsis,trueAnomaly);

Add a receiver to the satellite.

rx = receiver(sat);

Add a ground station to the scenario.

latitude = 0;                             % degrees
longitude = 30;                           % degrees
gs = groundStation(sc,latitude,longitude);

Add a transmitter to the ground station.

tx = transmitter(gs,MountingAngles=[0; 180; 0]);

Add a link analysis to the transmitter.

lnk = link(tx,rx);

Obtain the received isotropic power and power at receiver input on 13 October 2021 at 10:06 AM UTC.

time = datetime(2021,10,13,10,6,0);
[PISO,PRI] = sigstrength(lnk,time)

PISO = 
-3.0902e+03

PRI = 
-4.2145e+03

Input Arguments

lnk — Link analysis object

vector

Link analysis object, specified as a vector.

timeIn — Time at which output is calculated

datetime scalar

Time at which the output is calculated, specified as a datetime scalar. If no time zone is specified in timeIn, the time zone is assumed to be UTC.

Output Arguments

PISO — Received isotropic power

matrix

Received isotropic power in dBW, returned as a matrix. This output is the power level just before the receiver antenna, after accounting for the transmitter effective isotropic radiated power and path loss. The rows of the matrix correspond to the link object in lnk and the columns correspond to the time sample.

When the AutoSimulate property of the satellite scenario is true, the received isotropic power history from StartTime to StopTime is returned. Otherwise, the received isotropic power history from StartTime to SimulationTime is returned.

PRI — Power at receiver input

matrix

Power at receiver input in dBW, returned as a matrix. This output is the power level after adding the receiver antenna gain in the direction of the received signal to PISO and subtracting PreReceiverLoss of the receiver. The rows of the matrix correspond to the link object in lnk and the columns correspond to the time sample.

When the AutoSimulate property of the satellite scenario is true, the history of power at the receiver input from StartTime to StopTime is returned. Otherwise, the history of power at the receiver input from StartTime to SimulationTime is returned.

timeOut — Time samples of received isotropic power and power at receiver input

datetime scalar | datetime row vector

Time samples of received isotropic power, PISO, and power at receiver input, PRI, returned as a datetime scalar. If time histories of PISO and PRI are returned, timeOut is a datetime row vector.

Version History

Introduced in R2022b