AerospaceAngleOnlyIR

Sensor specification for infrared sensor that reports angle-only measurements

Since R2024b

Description

The AerospaceAngleOnlyIR object contains a sensor specification for an infrared sensor that reports angle-only measurements. You can use the AerospaceAngleOnlyIR object as an input to multiSensorTargetTracker.

Creation

To create an AerospaceAngleOnlyIR object, use the trackerSensorSpec function with the "aerospace", "infrared", and "angle-only" input arguments. For example:

spec = trackerSensorSpec("aerospace","infrared","angle-only")

Properties

IsGeographic — Option to enable tracking in geographic scenario

false (default) | true

Since R2026a

Option to enable tracking in a geographic scenario, specified as true or false. For more information, see Tracking Aerospace Targets in Geographic Scenario.

• When you set this property to true, you can specify the PlatformPosition property and corresponding data format with geodetic data of the form [latitude;longitude;altitude], in units of [degrees;degrees;meters]. You can also specify the reference frame for other sensor properties and corresponding data formats using the GeographicReferenceFrame property. Additionally, a sensor that is tracking in a geographic scenario takes the earth curvature into account for its detectability model, so that the sensor's field of view is limited by the true horizon.

• When you set this property to false, the expected sensor data is represented in a user-defined reference frame. This user-defined reference frame must be consistent with the definition of the target specifications.

Data Types: logical

GeographicReferenceFrame — Reference frame for sensor properties and data formats in geographic scenario

"NED" (default) | "ENU" | "ECEF"

Since R2026a

Reference frame for the sensor properties and data formats in a geographic scenario, specified as "NED", "ENU", or "ECEF".

• When this property is "NED" or "ENU", the PlatformOrientation property and corresponding data format item are with respect to a local NED or ENU coordinate frame with an origin at its concurrent location [latitude;longitude;altitude].

• When this property is "ECEF", the PlatformOrientation property and corresponding data format item are with respect to the ECEF frame. The origin of this frame is at the Earth's center of mass, the x-axis extends through the equator at the prime meridian, the y-axis extends through the equator at 90 degrees east longitude, and the z-axis extends through the North Pole.

To enable this property, set the IsGeographic property to true.

Example: "ENU"

Data Types: single | double

Terrain — Terrain data file to read

string scalar | character vector

Since R2026a

Terrain data file to read, specified as a string scalar or character vector representing the path to a DTED data file. The terrain impacts the computation of detection probability of targets.

To enable this property, set the IsGeographic property to true.

Example: "./n39_w106_3arc_v2.dt1"

MaxNumLooksPerUpdate — Maximum number of looks per update

30 (default) | 1 | positive integer

Maximum number of looks per update, specified as 1 if the sensor is not scanning and as a positive integer greater than 1 if the sensor is scanning.

Example: 40

Data Types: single | double

MaxNumMeasurementsPerUpdate — Maximum number of measurements per update

10 (default) | positive integer

Maximum number of measurements per update, specified as a positive integer.

Example: 10

Data Types: single | double

IsPlatformStationary — Enable stationary mounting platform

true (default) | false

Enable stationary mounting platform for the sensor, specified as true or false.

• Specify true to use PlatformPosition and PlatformOrientation to define the platform position and orientation.

• Specify false to use the input data format to define the platform position, velocity, and orientation at any given time. You can use the dataFormat function on the spec object to determine the tracker's input data format.

Example: true

Data Types: logical

PlatformPosition — Mounting platform position

[0 0 0] (default) | 1-by-3 real-valued vector

Position of the mounting platform for the sensor, specified as a 1-by-3 real-valued vector. If the IsGeographic property is false, position is in an user-defined reference frame and the units are in meters. If the IsGeographic property is true, position is of the form [latitude;longitude;altitude] with respect to the ECEF frame, in units of [degrees;degrees;meters].

To enable this property, set the IsPlatformStationary property to true.

Example: [-2 0 0.75]

Data Types: single | double

PlatformOrientation — Mounting platform orientation

[1 0 0; 0 1 0; 0 0 1] (default) | 3-by-3 real-valued matrix

Orientation of the mounting platform for the sensor, specified as a 3-by-3 real-valued rotation matrix. To enable this property, set the IsPlatformStationary property to "true".

Example: [1 0 0; 0 0.8660 -0.5000; 0 0.5000 0.8660]

Data Types: single | double

MountingLocation — Sensor location on platform

[0 0 0] (default) | 1-by-3 real-valued vector

Sensor location on the platform, specified as a 1-by-3 real-valued vector of form [x_m y_m z_m]. This property defines the coordinates of the sensor with respect to the platform origin. The default value specifies that the sensor origin is at the origin of its platform. Units are in meters.

Example: [1.25 -0.1 0.8]

Data Types: single | double

MountingAngles — Orientation of sensor

[0 0 0] (default) | 1-by-3 real-valued vector

Orientation of the sensor with respect to the platform, specified as a 1-by-3 real-valued vector of form [z_yaw y_pitch x_roll]. Each element of the vector corresponds to an intrinsic Euler angle rotation that carries the body axes of the platform to the sensor axes. The three elements describe the rotations around the z-, y-, and x-axis sequentially. Units are in degrees.

Data Types: single | double

HasElevation — Enable sensor to report target elevation

true (default) | false

Enable sensor to report target elevation, specified as true or false.

Example: true

Data Types: logical

FieldOfView — Field of view of sensor beam

[60 20] (default) | 1-by-2 real-valued vector

Field of view of the sensor beam at each look angle, specified as a 1-by-2 real-valued vector of the form [azimuth elevation]. Units are in degrees.

Example: [80 10]

Data Types: single | double

RangeLimits — Minimum and maximum detection range of sensor

[0 1e5] (default) | 1-by-2 nonnegative real-valued vector

Minimum and maximum detection range of the sensor, specified as a 1-by-2 nonnegative real-valued vector of the form [Rmin Rmax]. The radar does not detect targets that are outside this range. The maximum range, Rmax, must be greater than the minimum range, Rmin. Units are in meters.

Example: [0 5e4]

Data Types: single | double

AzimuthResolution — Azimuth resolution of sensor

1 (default) | positive scalar

Azimuth resolution of the sensor, specified as a positive scalar. The azimuth resolution defines the minimum separation in azimuth angle at which the sensor can distinguish between two targets. Units are in degrees.

Example: 0.3

Data Types: single | double

ElevationResolution — Elevation resolution of sensor

5 (default) | positive scalar

Elevation resolution of the sensor, specified as a positive scalar. The elevation resolution defines the minimum separation by the elevation angle at which the sensor can distinguish between two targets. Units are in degrees.

To enable this property, set the HasElevation property to true.

Example: 2.5

Data Types: single | double

DetectionProbability — Probability of detecting target inside coverage limits

0.9 (default) | scalar in the range (0,1]

Probability of detecting a target inside the coverage limits, specified as a scalar in the range (0, 1].

Example: 0.75

Data Types: single | double

FalseAlarmRate — False alarm report rate

1e-6 (default) | scalar in the range (0,1]

False alarm report rate within each sensor resolution cell, specified as a positive scalar in the range (0,1]. Units are dimensionless. The object determines resolution cells from the AzimuthResolution and RangeResolution properties and, when enabled, from the ElevationResolution and RangeRateResolution properties.

Example: 1e-4

Data Types: single | double

Object Functions

dataFormat

Structure for data format required by task-oriented tracker

More About

Data Format Required By Task-Oriented Tracker

When you initialize a tracker using this object, you need sensor data to update the tracker. For a full list of required sensor data and their descriptions, see the table below. See the dataFormat function for details on updating the tracker with sensor data.

Field Name	Description	Comment
LookTime	Timestamps of sensor scans, specified as an N-element row vector. N must be smaller than the value specified in the MaxNumLooksPerUpdate property.	None
LookAzimuth	Look azimuth angles at LookTime, specified as an N-element row vector. Units are in degrees.	None
LookElevation	Look elevation angles at LookTime, specified as an N-element row vector. Units are in degrees.	Applies only when the HasElevation property is set to "true".
PlatformPosition	Platform position, specified as a 3-by-N matrix. Each column represents the [x;y;z] platform coordinates at the corresponding LookTime. Units are in meters.	Applies only when the IsPlatformStationary property is set to "false".
PlatformOrientation	Platform orientation, specified as a 3-by-3-N matrix. Each 3-by-3 slice represents the rotation matrix at the corresponding LookTime. Units are in degrees.	Applies only when the IsPlatformStationary property is set to "false".
DetectionsTimes	Timestamps of detections, specified as an M-element row vector. M must be smaller than the value specified in the MaxNumMeasurementsPerUpdate property.	None
Azimuth	Detection azimuth angles of observed targets, specified as an M-element row vector. Units are in degrees.	None
Elevation	Detection elevation angles of observed targets, specified as an M-element row vector. Units are in degrees.	Applies only when the HasElevation property is set to "true".
AzimuthAccuracy	Standard deviation of azimuth angle measurements, specified as an M-element row vector. Units are in degrees.	None
ElevationAccuracy	Standard deviation of elevation angle measurements, specified as an M-element row vector. Units are in degrees.	Applies only when the HasElevation property is set to "true".

Tip

To update the tracker at a timestamp when the sensor scan is not complete, specify "LookTime" as empty using zeros(0,1,dataType).

Tracking Aerospace Targets in Geographic Scenario

Tracking specifications offer flexibility by allowing the use of arbitrary reference frames for defining track states, provided that the reference frame remains consistent between sensor and target specifications.

In geographic tracking scenarios, it is common to use geodetic reference frames for position (longitude, latitude, altitude) and local NED/ENU reference frames for velocity, orientation, and acceleration. Here, local means the reference frame's origin is at the geodetic position of each data item.

To avoid the need for manual data conversion to a consistent reference frame, you can specify the IsGeographic (since R2026a) and GeographicReferenceFrame (since R2026a) properties of the target and sensor specifications to enable a geographic tracking scenario. The geographic tracking scenario allows the use of geodetic value for position, and local NED/ENU frame for other state variables.

These tables illustrate how geographic tracking scenarios modify the target and sensor specifications.

• Target State Transition Modeling

  Property Settings	Position Reference Frame	Velocity Reference Frame
  IsGeographic = false	User defined.	User defined.
  IsGeographic = True GeographicReferenceFrame = "NED"	ECEF.	Local NED. Local indicates that the origin of the reference frame is at the geodetic position of each data item.
  IsGeographic = True GeographicReferenceFrame = "ENU"	ECEF.	Local ENU. Local indicates that the origin of the reference frame is at the geodetic position of each data item.

• Target Survival Modeling:

  Property Settings	Survival Model	Comments
  IsGeographic = false	Uniform survival rate survival model.	During coasting, track survival does not depend on position.
  IsGeographic = True	Region of interest survival model. An altitude value below zero defines a region in which tracks have a lower probability of survival during prediction.	Tracks are deleted rapidly when their altitude falls below the Earth's surface.

• Sensor Data Formats and Properties:

  Property Settings	Platform Position Reference Frame	Platform Orientation Reference Frame	Platform Angular Velocity Reference Frame (Monostatic Radar Only)	Platform Velocity Reference Frame (Monostatic Radar Only)
  IsGeographic = false	User defined.	User defined.	Platform body.	User defined.
  IsGeographic = True GeographicReferenceFrame = "NED"	Geodetic ([latitude;longitude;altitude]).	Local NED. Local indicates that the origin of the reference frame is at the geodetic position of each data item.	Platform body.	Local NED. Local indicates that the origin of the reference frame is at the geodetic position of each data item.
  IsGeographic = True GeographicReferenceFrame = "ENU"	Geodetic ([latitude;longitude;altitude]).	Local ENU. Local indicates that the origin of the reference frame is at the geodetic position of each data item.	Platform body.	Local ENU. Local indicates that the origin of the reference frame is at the geodetic position of each data item.

Additionally, you can use the Terrain (since R2026a) property of the sensor specifications to provide terrain data, which impacts the computation of detection probability.

Tips

• To deploy an application that uses sensor specifications with terrain using MATLAB^® Compiler™, add the DTED files to the deployed application package. To do this, you can either use the -a filepath (MATLAB Compiler) input argument of the mcc (MATLAB Compiler) function or follow the prompts in the Standalone Application Compiler (MATLAB Compiler) app.

• You can find and download DTED files by using EarthExplorer, a data portal provided by the US Geological Survey (USGS). From the list of data sets, search for DTED files by selecting Digital Elevation, SRTM, and then SRTM 1 Arc-Second Global and SRTM Void Filled.

Extended Capabilities

C/C++ Code Generation

Generate C and C++ code using MATLAB® Coder™.

Usage notes and limitations:

To generate code, you must set the following nontunable properties before setting any other property.

• HasElevation

Version History

Introduced in R2024b

R2026a: Tracking aerospace targets in geographic scenario

You can use the new IsGeographic and GeographicReferenceFrame properties to enable a geographic tracking scenario. For more information, see Tracking Aerospace Targets in Geographic Scenario

Additionally, you can use the new Terrain property to provide terrain data.