| Earth Observation Mission CFI Software Pointing Software User Manual for JAVA |

Public Member Functions | Public Attributes

# EECFI.Target Class Reference

Class for target calculations. More...

Inheritance diagram for EECFI.Target:

List of all members.

## Public Member Functions
| Target (final Attitude att, final DemId dem, final AtmosId atmos) throws CfiError
| Class constructor.
void | close () throws CfiError
| Release all resources managed by this object.
native void | targetInter (final SatId satId, long deriv, long interFlag, double losAz, double losEl, double geodAlt, double losAzRate, double losElRate, long iray, double freq) throws CfiError
| Compute the first or the second intersection point of the line of sight from the satellite with a surface located at a certanin geodetic altitude over the Earth.
native void | targetTravelTime (final SatId satId, long deriv, double losAz, double losEl, double travelTime, double losAzRate, double losElRate, double travelTimeRate, long iray, double freq) throws CfiError
| It computes the point of the line or sight from the satellite at a given travel time along the line of sight.
native void | targetGroundRange (final SatId satId, long deriv, double losAz, double losEl, double geodAlt, double distance, double losAzRate, double losElRate) throws CfiError
| It computes the location of a point that is placed on a surface at a certain geodetic altitude over the Earth, that lays on the plane defined by the satellite position, the nadir and a reference point.
native void | targetIncidenceAngle (final SatId satId, long deriv, double losAz, double incidenceAngle, double geodAlt, double losAzRate) throws CfiError
| It computes the location of a point that is placed on a surface at a certain geodetic altitude over the Earth and that is seen from the satellite on a line of sight that forms a certain azimuth angle in the selected Attitude Frame and that intersects that surface with a certain incidence angle.
native void | targetRange (final SatId satId, long deriv, double losAz, double range, double geodAlt, double losAzRate, double rangeRate) throws CfiError
| It computes the location of a point that is placed on a surface at a certain geodetic altitude over the Earth, that is seen from the satellite on a line of sight that forms a certain azimuth angle in the selected Attitude Frame, and that is at a certain range or slant-range from the satellite.
native void | targetRangeRate (final SatId satId, long deriv, double efRangeRate, double range, double geodAlt, double efRangeRateRate, double rangeRate) throws CfiError
| It computes the location of a point that is placed on a surface at a certain geodetic altitude over the Earth, that is at a certain range from the satellite, and whose associatedEarth-fixed target has a certain range-rate value.
native void | targetTangent (final SatId satId, long deriv, double losAz, double losEl, double losAzRate, double losElRate, long iray, double freq) throws CfiError
| It computes the location of the tangent point over the Earth that is located on the line of sight defined by an elevation and azimuth angles expressed in the selected Attitude Frame.
native void | targetAltitude (final SatId satId, long deriv, double losAz, double geodAlt, double losAzRate, long iray, double freq) throws CfiError
| It computes the location of the tangent point over the Earth that is located on a surface at a certain geodetic altitude over the Earth and that is on a line of sight that forms a certain azimuth angle in the selected Attitude Frame.
native void | targetStar (final SatId satId, long deriv, double starRa, double starDec, double starRaRate, double starDecRate, long iray, double freq) throws CfiError
| It computes the location of the tangent point over the Earth that is located on the line of sight that points to a star defined by its right ascension and declination coordinates.
native void | targetTangentSun (final SatId satId, long deriv, long iray, double freq) throws CfiError
| It computes the location of the tangent point over the Earth that is located on the line of sight that points to the Sun.
native void | targetTangentMoon (final SatId satId, long deriv, long iray, double freq) throws CfiError
| It computes the location of the tangent point over the Earth that is located on the line of sight that points to the Moon.
native void | targetStation (final SatId satId, long deriv, double geocLong, double geodLat, double geodAlt, double minLinkEl) throws CfiError
| It computes the most relevant observation parameters of the link between the satellite and a ground station.
native void | targetGeneric (final SatId satId, long deriv, double[] targPos, double[] targVel, double[] targAcc) throws CfiError
| It allows the user to provide the target location (position and velocity) and later calculate extra results from it.
native void | targetReflected (final SatId satId, long deriv, double geodAlt, double deflectionNorth, double deflectionEast, long sourceType, double[] sourceParam) throws CfiError
| It allows the user to compute, from S/C position and attitude, and emitting source position, the point of reflection from the source towards the SC at a certain geodetic altitude.
native void | targetSc (final SatId satId1, final SatId satId2, final Attitude att2, long deriv) throws CfiError
| It computes the pointing from one satellite to another satellite.
native void | multiTargetInter (final SatId satId, long deriv, long interFlag, double losAz, double losEl, long numTarget, double[] geodAlt, double losAzRate, double losElRate, long iray, double freq) throws CfiError
| It computes the first or the second intersection points of the line of sight from the satellite with surfaces located at certain geodetic altitudes over the Earth.
native void | multiTargetTravelTime (final SatId satId, long deriv, double losAz, double losEl, long numTarget, double[] travelTime, double losAzRate, double losElRate, double travelTimeRate, long iray, double freq) throws CfiError
| It computes the points of the line or sight from the satellite at given travel times along the (curved) line of sight.
native TargetOutput | targetListInter (final SatId satId, long deriv, long interFlag, final InstrumentData instrData, double geodAlt)
| Compute the first or the second intersection point of the line of sight from the satellite with a surface located at a certanin geodetic altitude over the Earth for a set of azimuth/elevation points.
native TargetExtra | extraVector (long choice, long targetType, long targetNumber) throws CfiError
| It provides the following output parameters for target(s): target position, velocity and acceleration vectors, line of sight direction, range, travel time and their corresponding derivatives.
native TargetExtra | extraMain (long choice, long targetType, long targetNumber) throws CfiError
| It computes the extra parameter for the target(s) in input data structure.
native TargetExtra | extraAux (long choice, long targetType, long targetNumber) throws CfiError
| It computes auxiliary parameters for the target in input data structure.
native TargetExtra | extraTargetToSun (long choice, long targetType, long targetNumber, long iray, double freq) throws CfiError
| It computes extra parameters related to the pointing fromthe target in input data structure to the sun.
native TargetExtra | extraTargetToMoon (long choice, long targetType, long targetNumber, long iray, double freq) throws CfiError
| It computes extra parameters related to the pointing from the target in input data structure to the moon.
native TargetExtra | extraEfTarget (long choice, long targetType, long targetNumber, double freq) throws CfiError
| It computes the parameter for an Earth fixed target related to the target in input data structure.
native TargetExtra | extraSpecularReflection (long choice, long targetType, long targetNumber, double deflectionNorth, double deflectionEast) throws CfiError
| It calculates the direction of the specular reflection associated to a given target.
native TargetExtraResultsList | extraListVector (long choice, long targetType) throws CfiError
| It provides the following output parameters for targets computed.
native TargetExtraResultsList | extraListMain (long choice, long targetType) throws CfiError
| It computes the extra parameter for the targets computed with targetList methods.
native TargetExtraResultsList | extraListAux (long choice, long targetType) throws CfiError
| It computes auxiliary parameters for the targets computed with targetList methods.
native TargetExtraResultsList | extraListTargetToSun (long choice, long targetType, long iray, double freq) throws CfiError
| It computes extra parameters related to the pointing from the targets computed with targetList methods to the sun.
native TargetExtraResultsList | extraListTargetToMoon (long choice, long targetType, long iray, double freq) throws CfiError
| It computes extra parameters related to the pointing from the targets computed with targetList methods to the moon.
native TargetExtraResultsList | extraListEfTarget (long choice, long targetType, double freq) throws CfiError
| It computes the parameter for an Earth fixed target related to the targets computed with targetList methods.
native TargetExtraResultsList | extraListSpecularReflection (long choice, long targetType, double deflectionNorth, double deflectionEast) throws CfiError
| It calculates the direction of the specular reflection associated to the targets computed with targetList methods.
native SatId | satId ()
| Return satellite id.
native TargetIdData[] | getData () throws CfiError
| It gets target parameters.
## Public Attributes
long | numUserTarget
| Number of user defined targer calculated.
long | numLosTarget
| Number of Line Of Sight target calculated.

## Detailed Description

Class for target calculations.

## Constructor & Destructor Documentation

SatId EECFI.Target::Target | ( | final Attitude | att,
|  | final DemId | dem,
|  | final AtmosId | atmos |
| ) |  |  | throws CfiError

Class constructor.

The created object allocates resources that must be released calling the method Target.close() when the computations are finished.

Target class can be used in a try-with-resources block, at the end of which the Target.close() method will be automatically called without need of doing it explicitely.

## Member Function Documentation

void EECFI.Target::close | ( |  | ) | throws CfiError

Release all resources managed by this object.

Free memory when the Garbage collector is called.

IMPORTANT: The life time of the EOCFI Java objects must be explicitly managed by the program work flow. Failure to perform this release will lead to resource leakage and might have a significant impact in performance.

TargetExtra EECFI.Target::extraAux | ( | long | choice,
|  | long | targetType,
|  | long | targetNumber |
| ) |  |  | throws CfiError

It computes auxiliary parameters for the target in input data structure.

Note on targetNumber when more than one user target is computed: the targetNumber to be used to get a specific LOS target is an incremental number. That is, if there are N user targets US1, US2, ... USN and a number of LOS targets for every user target NLOS1, NLOS2, ..., NLOSN, if we want to get LOS target with index 1 corresponding to user target US3, the targetNumber to be used must be NLOS1+NLOS2+1.
The targetNumber can also be get with the returned array by Target.getData.

Parameters:

  | choice | Flag to select the extra results to be computed (TargetResAuxNameEnum). Even though derivatives could be requested by user, they will not be calculated if the target was computed without derivatives (a warning is raised in this case).
  | targetType | Flag to select the type of target (TargetTypeEnum).
  | targetNumber | Target number.

Returns:
  Results vector; components:
  [0] Radius of curvature in the look direction at the nadir of the target (Earth fixed CS) [m]
  [1] Distance from the nadir of the target to the satellite nadir (EF CS) [m]
  [2] Minimum distance from the nadir of the target to the ground track (EF CS) [m]
  [3] Distance from the SSP to the point located on the ground track that is at a minimum distance from the nadir of the target (EF CS) [m]
  [4] Mean Local Solar Time at target [decimal hour]
  [5] True Local Solar Time at target [decimal hour]
  [6] Right ascension at which the look direction from the satellite to the target points at target point (True of Date CS) [deg]
  [7] Declination at which the look direction from the satellite to the target points at target point (True of Date CS) [deg].
  Results rate vector; components:
  [0] Radius of curvature-rate in the look direction at the nadir of the target (Earth fixed CS) [m/s]
  [1] Distance-rate from the nadir of the target to the satellite nadir (EF CS) [m/s]
  [2] Distance-rate from the nadir of the target to the ground track (EF CS) [m/s]
  [3] Distance-rate from the SSP to the point located on the ground track that is at a minimum distance from the nadir of the target (EF CS) [m/s]
  [4-7] dummy
  [8] Northward component of the velocity relative to the Earth of the nadir of the target (Topocentric CS) [m/s]
  [9] Eastward component of the velocity relative to the Earth of the nadir of the target (Topocentric CS) [m/s]
  [10] Azimuth of the velocity relative to the Earth of the nadir of the target.(Topocentric CS) [deg]

Results rate rate vector; components:
[0] Radius of curvature-rate-rate in the look direction at the nadir of the target (Earth fixed CS) [m/s]
[1] Distance-rate-rate from the nadir of the target to the satellite nadir (EF CS) [m/s]
[2] Distance-rate-rate from the nadir of the target to the ground track (EF CS) [m/s]
[3] Distance-rate-rate from the SSP to the point located on the ground track that is at a minimum distance from the nadir of the target (EF CS) [m/s].

TargetExtra EECFI.Target::extraEfTarget | ( | long | choice,
|  | long | targetType,
|  | long | targetNumber,
|  | double | freq |
| ) |  |  | throws CfiError

It computes the parameter for an Earth fixed target related to the target in input data structure.

Note on targetNumber when more than one user target is computed: the targetNumber to be used to get a specific LOS target is an incremental number. That is, if there are N user targets US1, US2, ... USN and a number of LOS targets for every user target NLOS1, NLOS2, ..., NLOSN, if we want to get LOS target with index 1 corresponding to user target US3, the targetNumber to be used must be NLOS1+NLOS2+1.
The targetNumber can also be get with the returned array by Target.getData.

Parameters:

  | choice | Flag to select the extra results to be computed (DerivPointingEnum). Even though derivatives could be requested by user, they will not be calculated if the target was computed without derivatives (a warning is raised in this case).
  | targetType | Flag to select the type of target (TargetTypeEnum).
  | targetNumber | Target number.
  | freq | Frequency of the signal [Hz]. Allowed range: >0.

Returns:
  Results rate and rate-rate vectors; components:
  [0] 2-way Doppler shift of the signal (Earth Fixed CS) [Hz]
  [1] Earthfixed target to satellite range-rate (EF CS) [m/s]
  [2] Earthfixed target to satellite azimuth-rate (EF CS) [deg/s]
  [3] Earthfixed target to satellite elevation-rate (EF CS) [deg/s]
  [4] Satellite to earthfixed target azimuth-rate (Topocentric CS) [deg/s]
  [5] Satellite to earthfixed target elevation-rate (Topocentric CS) [deg/s]
  [6] Satellite to earthfixed target azimuth-rate (Attitude Frame) [deg/s]
  [7] Satellite to earthfixed target elevation-rate (Attitude Frame) [deg/s].

TargetExtraResultsList EECFI.Target::extraListAux | ( | long | choice,
|  | long | targetType |
| ) |  |  | throws CfiError

It computes auxiliary parameters for the targets computed with targetList methods.

Parameters:

  | choice | Flag to select the extra results to be computed (TargetResAuxNameEnum). Even though derivatives could be requested by user, they will not be calculated if the target was computed without derivatives (a warning is raised in this case).
  | targetType | Flag to select the type of target (TargetTypeEnum).

Returns:
  It contains the results for every target computed with targetList method. For the meaning of every position of output vectors, see method Target.extraAux

TargetExtraResultsList EECFI.Target::extraListEfTarget | ( | long | choice,
|  | long | targetType,
|  | double | freq |
| ) |  |  | throws CfiError

It computes the parameter for an Earth fixed target related to the targets computed with targetList methods.

Parameters:

  | choice | Flag to select the extra results to be computed (DerivPointingEnum). Even though derivatives could be requested by user, they will not be calculated if the target was computed without derivatives (a warning is raised in this case).
  | targetType | Flag to select the type of target (TargetTypeEnum).
  | freq | Frequency of the signal [Hz]. Allowed range: >0.

Returns:
  It contains the results for every target computed with targetList method. For the meaning of every position of output vectors, see method Target.extraEfTarget. Note: only derivatives are meaningful in this case.

TargetExtraResultsList EECFI.Target::extraListMain | ( | long | choice,
|  | long | targetType |
| ) |  |  | throws CfiError

It computes the extra parameter for the targets computed with targetList methods.

Parameters:

  | choice | Flag to select the extra results to be computed (TargetResMainNameEnum). Even though derivatives could be requested by user, they will not be calculated if the target was computed without derivatives (a warning is raised in this case).
  | targetType | Flag to select the type of target (TargetTypeEnum).

Returns:
  It contains the results for every target computed with targetList method. For the meaning of every position of output vectors, see method Target.extraMain

TargetExtraResultsList EECFI.Target::extraListSpecularReflection | ( | long | choice,
|  | long | targetType,
|  | double | deflectionNorth,
|  | double | deflectionEast |
| ) |  |  | throws CfiError

It calculates the direction of the specular reflection associated to the targets computed with targetList methods.

Parameters:

  | choice | Flag to select the extra results to be computed (DerivPointingEnum). Even though derivatives could be requested by user, they will not be calculated if the target was computed without derivatives (a warning is raised in this case).
  | targetType | Flag to select the type of target (TargetTypeEnum).
  | targetNumber | Target number.
  | deflectionNorth | North-South component of the vertical deflection [deg]. Allowed range: >=-90; <=90.
  | deflectionEast | East-West component of the vertical deflection [deg]. Allowed range: >=-90; <=90.

Returns:
  It contains the results for every target computed with targetList method. For the meaning of every position of output vectors, see method Target.extraListSpecularReflection.

TargetExtraResultsList EECFI.Target::extraListTargetToMoon | ( | long | choice,
|  | long | targetType,
|  | long | iray,
|  | double | freq |
| ) |  |  | throws CfiError

It computes extra parameters related to the pointing from the targets computed with targetList methods to the moon.

Parameters:

  | choice | Flag to select the extra results to be computed (DerivPointingEnum). Even though derivatives could be requested by user, they will not be calculated if the target was computed without derivatives (a warning is raised in this case).
  | targetType | Flag to select the type of target (TargetTypeEnum).
  | iray | Ray tracing model switch (not used).
  | freq | Frequency of the signal [Hz]. Allowed range: >0.

Returns:
  It contains the results for every target computed with targetList method. For the meaning of every position of output vectors, see method Target.extraTargetToMoon.

TargetExtraResultsList EECFI.Target::extraListTargetToSun | ( | long | choice,
|  | long | targetType,
|  | long | iray,
|  | double | freq |
| ) |  |  | throws CfiError

It computes extra parameters related to the pointing from the targets computed with targetList methods to the sun.

Note: it can be internally applied a correction to computations in order to compensate for the travel time of light from the Sun to the Earth and the satellites orbiting it. To activate this compensation, the Sun model in xl_model_id must be initialized with the enum XL_MODEL_SUN_TRAVEL_TIME using the function xl_model_init (see [LIBSUM]).

Parameters:

  | choice | Flag to select the extra results to be computed (DerivPointingEnum). Even though derivatives could be requested by user, they will not be calculated if the target was computed without derivatives (a warning is raised in this case).
  | targetType | Flag to select the type of target (TargetTypeEnum).
  | iray | Ray tracing model switch (not used).
  | freq | Frequency of the signal [Hz]. Allowed range: >0.

Returns:
  It contains the results for every target computed with targetList method. For the meaning of every position of output vectors, see method Target.extraTargetToSun.

TargetExtraResultsList EECFI.Target::extraListVector | ( | long | choice,
|  | long | targetType |
| ) |  |  | throws CfiError

It provides the following output parameters for targets computed.

with targetList methods: target position, velocity and acceleration vectors, line of sight direction, range, travel time and their corresponding derivatives.

Parameters:

  | choice | Flag to select the extra results to be computed (DerivPointingEnum). Even though derivatives could be requested by user, they will not be calculated if the target was computed without derivatives (a warning is raised in this case).
  | targetType | Flag to select the type of target (TargetTypeEnum).

Returns:
  It contains the results for every target computed with targetList method. For the meaning of every position of output vectors, see method Target.extraVector.

TargetExtra EECFI.Target::extraMain | ( | long | choice,
|  | long | targetType,
|  | long | targetNumber |
| ) |  |  | throws CfiError

It computes the extra parameter for the target(s) in input data structure.

Note on targetNumber when more than one user target is computed: the targetNumber to be used to get a specific LOS target is an incremental number. That is, if there are N user targets US1, US2, ... USN and a number of LOS targets for every user target NLOS1, NLOS2, ..., NLOSN, if we want to get LOS target with index 1 corresponding to user target US3, the targetNumber to be used must be NLOS1+NLOS2+1.
The targetNumber can also be get with the returned array by Target.getData.

Parameters:

  | choice | Flag to select the extra results to be computed (TargetResMainNameEnum). Even though derivatives could be requested by user, they will not be calculated if the target was computed without derivatives (a warning is raised in this case).
  | targetType | Flag to select the type of target (TargetTypeEnum).
  | targetNumber | Target number.

Returns:
  Results vector and rates; components:
  [0] Target geocentric longitude (EF CS) [deg]
  [1] Target geocentric latitude (EF CS) [deg]
  [2] Target geodetic latitude (EF CS) [deg]
  [3] Target geodetic altitude (EF CS) [deg]
  [4] Satellite to target azimuth (Topocentric CS) [deg]
  [5] Satellite to target elevation (Topocentric CS) [deg]
  [6] Satellite to target pointing: Azimuth (Attitude Frame) [deg]
  [7] Satellite to target pointing: Elevation (Attitude Frame) [deg]
  [8] Target to Satellite pointing: Azimuth (Topocentric CS) [deg]
  [9] Target to Satellite pointing: Elevation (Topocentric CS) [deg]
  [10] Target to source Satellite pointing: Azimuth (Attitude frame) [deg] (Note: this value is only meaningful when target has been computed with xp_target_sc)
  [11] Target to source Satellite pointing: Elevation (Attitude frame) [deg] (Note: this value is only meaningful when target has been computed with xp_target_sc).

TargetExtra EECFI.Target::extraSpecularReflection | ( | long | choice,
|  | long | targetType,
|  | long | targetNumber,
|  | double | deflectionNorth,
|  | double | deflectionEast |
| ) |  |  | throws CfiError

It calculates the direction of the specular reflection associated to a given target.

Note on targetNumber when more than one user target is computed: the targetNumber to be used to get a specific LOS target is an incremental number. That is, if there are N user targets US1, US2, ... USN and a number of LOS targets for every user target NLOS1, NLOS2, ..., NLOSN, if we want to get LOS target with index 1 corresponding to user target US3, the targetNumber to be used must be NLOS1+NLOS2+1.
The targetNumber can also be get with the returned array by Target.getData.

Parameters:

  | choice | Flag to select the extra results to be computed (DerivPointingEnum). Even though derivatives could be requested by user, they will not be calculated if the target was computed without derivatives (a warning is raised in this case).
  | targetType | Flag to select the type of target (TargetTypeEnum).
  | targetNumber | Target number.
  | deflectionNorth | North-South component of the vertical deflection [deg]. Allowed range: >=-90; <=90.
  | deflectionEast | East-West component of the vertical deflection [deg]. Allowed range: >=-90; <=90.

Returns:
  Results vector, rate-vector and rate-rate vector; components:
  [0] X coordinate of reflected pointing direction (EF CS) [m]
  [1] Y coordinate of reflected pointing direction (EF CS) [m]
  [2] Z coordinate of reflected pointing direction (EF CS) [m]
  [3] Azimuth of the reflected pointing direction (Topocentric CS) [deg]
  [4] Elevation of the reflected pointing direction (Topocentric CS) [deg]
  [5] Right ascension at which the reflected pointing direction points at target point (True of Date CS) [deg]
  [6] Declination at which the reflected pointing direction points at target point (True of Date CS) [deg].

TargetExtra EECFI.Target::extraTargetToMoon | ( | long | choice,
|  | long | targetType,
|  | long | targetNumber,
|  | long | iray,
|  | double | freq |
| ) |  |  | throws CfiError

It computes extra parameters related to the pointing from the target in input data structure to the moon.

Note on targetNumber when more than one user target is computed: the targetNumber to be used to get a specific LOS target is an incremental number. That is, if there are N user targets US1, US2, ... USN and a number of LOS targets for every user target NLOS1, NLOS2, ..., NLOSN, if we want to get LOS target with index 1 corresponding to user target US3, the targetNumber to be used must be NLOS1+NLOS2+1.
The targetNumber can also be get with the returned array by Target.getData.

Parameters:

  | choice | Flag to select the extra results to be computed (DerivPointingEnum). Even though derivatives could be requested by user, they will not be calculated if the target was computed without derivatives (a warning is raised in this case).
  | targetType | Flag to select the type of target (TargetTypeEnum).
  | targetNumber | Target number.
  | iray | Ray tracing model switch (not used).
  | freq | Frequency of the signal [Hz]. Allowed range: >0.

Returns:
  Results vector; components:
  [0] Target to Moon (centre) azimuth (Topocentric CS) [deg]
  [1] Target to Moon (centre) elevation (Topocentric CS) [deg]
  [2] Tangent altitude over the Earth in the target to Moon (centre) look direction (EF CS) [m]
  [3] Target to Moon visibility flag (- 1: Moon eclipsed by the Earth; +1: Moon in sight).
  Results rate vector; components:
  [0] Target to Moon (centre) azimuth-rate (Topocentric CS) [deg/s]
  [1] Target to Moon (centre) elevation-rate (Topocentric CS) [deg/s].
  Results rate rate vector; components:
  [0] Target to Moon (centre) azimuth-rate-rate (Topocentric CS) [deg/s2]
  [1] Target to Moon (centre) elevation-rate-rate (Topocentric CS) [deg/s2].

TargetExtra EECFI.Target::extraTargetToSun | ( | long | choice,
|  | long | targetType,
|  | long | targetNumber,
|  | long | iray,
|  | double | freq |
| ) |  |  | throws CfiError

It computes extra parameters related to the pointing fromthe target in input data structure to the sun.

Note: 1) On targetNumber when more than one user target is computed: the targetNumber to be used to get a specific LOS target is an incremental number. That is, if there are N user targets US1, US2, ... USN and a number of LOS targets for every user target NLOS1, NLOS2, ..., NLOSN, if we want to get LOS target with index 1 corresponding to user target US3, the targetNumber to be used must be NLOS1+NLOS2+1.
The targetNumber can also be get with the returned array by Target.getData. 2) It can be internally applied a correction to computations in order to compensate for the travel time of light from the Sun to the Earth and the satellites orbiting it. To activate this compensation, the Sun model in xl_model_id must be initialized with the enum XL_MODEL_SUN_TRAVEL_TIME using the function xl_model_init (see [LIBSUM]).

Parameters:

  | choice | Flag to select the extra results to be computed (DerivPointingEnum). Even though derivatives could be requested by user, they will not be calculated if the target was computed without derivatives (a warning is raised in this case).
  | targetType | Flag to select the type of target (TargetTypeEnum).
  | targetNumber | Target number.
  | iray | Ray tracing model switch (not used).
  | freq | Frequency of the signal [Hz]. Allowed range: >0.

Returns:
  Results vector; components:
  [0] Target to Sun (centre) azimuth (Topocentric CS) [deg]
  [1] Target to Sun (centre) elevation (Topocentric CS) [deg]
  [2] Tangent altitude over the Earth in the target to Sun (centre) look direction (EF CS) [m]
  [3] Target to Sun visibility flag (- 1: Sun eclipsed by the Earth; +1: Sun in sight).
  Results rate vector; components:
  [0] Target to Sun (centre) azimuth-rate (Topocentric CS) [deg/s]
  [1] Target to Sun (centre) elevation-rate (Topocentric CS) [deg/s].
  Results rate rate vector; components:
  [0] Target to Sun (centre) azimuth-rate-rate (Topocentric CS) [deg/s2]
  [1] Target to Sun (centre) elevation-rate-rate (Topocentric CS) [deg/s2].

TargetExtra EECFI.Target::extraVector | ( | long | choice,
|  | long | targetType,
|  | long | targetNumber |
| ) |  |  | throws CfiError

It provides the following output parameters for target(s): target position, velocity and acceleration vectors, line of sight direction, range, travel time and their corresponding derivatives.

Note on targetNumber when more than one user target is computed: the targetNumber to be used to get a specific LOS target is an incremental number. That is, if there are N user targets US1, US2, ... USN and a number of LOS targets for every user target NLOS1, NLOS2, ..., NLOSN, if we want to get LOS target with index 1 corresponding to user target US3, the targetNumber to be used must be NLOS1+NLOS2+1.
The targetNumber can also be get with the returned array by Target.getData.

Parameters:

  | choice | Flag to select the extra results to be computed (DerivPointingEnum). Even though derivatives could be requested by user, they will not be calculated if the target was computed without derivatives (a warning is raised in this case).
  | targetType | Flag to select the type of target (TargetTypeEnum).
  | targetNumber | Target number.

Returns:
  Result vector and rates; components:
  [0] Target Position X (EF CS) [m]
  [1] Target Position Y (EF CS) [m]
  [2] Target Position Z (EF CS) [m]
  [3] Direction LOS X (EF CS) [m]
  [4] Direction LOS X (EF CS) [m]
  [5] Direction LOS X (EF CS) [m]
  [6] Range to Attitude Frame Origin [m]
  [7] Travel Time to Attitude Frame Origin [s].

TargetIdData EECFI.Target::getData | ( |  | ) | throws CfiError

It gets target parameters.

The returned array has one element for every user target, and every element has the list LOS targets corresponding to the user target.

Returns:
  Data of target id.

void EECFI.Target::multiTargetInter | ( | final SatId | satId,
|  | long | deriv,
|  | long | interFlag,
|  | double | losAz,
|  | double | losEl,
|  | long | numTarget,
|  | double[] | geodAlt,
|  | double | losAzRate,
|  | double | losElRate,
|  | long | iray,
|  | double | freq |
| ) |  |  | throws CfiError

It computes the first or the second intersection points of the line of sight from the satellite with surfaces located at certain geodetic altitudes over the Earth.

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | interFlag | Flag for first or second intersection point selection (XPCFI_INTER_1ST or XPCFI_INTER_2ND).
  | losAz | Azimuth of the LOS (Attitude frame) [deg]. Allowed range: >=0; <360.
  | losEl | Elevation of the LOS (Attitude frame) [deg]. Allowed range: >=-90; <=90.
  | numTarget | Number of user defined altitudes.
  | geodAlt | Geodetic altitude over the Earth [m]. Allowed range: >=-bWGS.
  | losAzRate | Azimuth rate of the LOS (Attitude frame) [deg/s].
  | losElRate | Elevation rate of the LOS (Attitude frame) [deg/s].
  | iray | Ray tracing model switch (not used).
  | freq | Frequency of the signal [Hz]. Allowed range: >0.

void EECFI.Target::multiTargetTravelTime | ( | final SatId | satId,
|  | long | deriv,
|  | double | losAz,
|  | double | losEl,
|  | long | numTarget,
|  | double[] | travelTime,
|  | double | losAzRate,
|  | double | losElRate,
|  | double | travelTimeRate,
|  | long | iray,
|  | double | freq |
| ) |  |  | throws CfiError

It computes the points of the line or sight from the satellite at given travel times along the (curved) line of sight.

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | losAz | Azimuth of the LOS (Attitude frame) [deg]. Allowed range: >=0; <360.
  | losEl | Elevation of the LOS (Attitude frame) [deg]. Allowed range: >=-90; <=90.
  | numTarget | Number of user defined altitudes.
  | travelTime | Travel time along the (curved) line of sight [s]. Allowed range: >0.
  | losAzRate | Azimuth rate of the LOS (Attitude frame) [deg/s].
  | losElRate | Elevation rate of the LOS (Attitude frame) [deg/s].
  | travelTimeRate | Travel time rate along the (curved) line of sight [s/s].
  | iray | Ray tracing model switch (not used).
  | freq | Frequency of the signal [Hz]. Allowed range: >0.

SatId EECFI.Target::satId | ( |  | ) |

Return satellite id.

Returns:
  Satellite id.

void EECFI.Target::targetAltitude | ( | final SatId | satId,
|  | long | deriv,
|  | double | losAz,
|  | double | geodAlt,
|  | double | losAzRate,
|  | long | iray,
|  | double | freq |
| ) |  |  | throws CfiError

It computes the location of the tangent point over the Earth that is located on a surface at a certain geodetic altitude over the Earth and that is on a line of sight that forms a certain azimuth angle in the selected Attitude Frame.

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | losAz | Azimuth of the LOS (Attitude frame) [deg]. Allowed range: >=0; <360.
  | geodAlt | Geodetic altitude over the Earth [m]. Allowed range: >=-bWGS.
  | losAzRate | Azimuth rate of the LOS (Attitude frame) [deg/s].
  | iray | Ray tracing model switch (not used).
  | freq | Frequency of the signal [Hz]. Allowed range: >0.

void EECFI.Target::targetGeneric | ( | final SatId | satId,
|  | long | deriv,
|  | double[] | targPos,
|  | double[] | targVel,
|  | double[] | targAcc |
| ) |  |  | throws CfiError

It allows the user to provide the target location (position and velocity) and later calculate extra results from it.

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | targPos | Target position vector (Earth Fixed CS) [m].
  | targVel | Target velocity vector (Earth Fixed CS) [m/s].
  | targAcc | Target acceleration vector (Earth Fixed CS) [m/s2].

void EECFI.Target::targetGroundRange | ( | final SatId | satId,
|  | long | deriv,
|  | double | losAz,
|  | double | losEl,
|  | double | geodAlt,
|  | double | distance,
|  | double | losAzRate,
|  | double | losElRate |
| ) |  |  | throws CfiError

It computes the location of a point that is placed on a surface at a certain geodetic altitude over the Earth, that lays on the plane defined by the satellite position, the nadir and a reference point.

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | losAz | Azimuth of the LOS (Attitude frame) [deg]. Allowed range: >=0; <360.
  | losEl | Elevation of the LOS (Attitude frame) [deg]. Allowed range: >=-90; <=90.
  | geodAlt | Geodetic altitude over the Earth [m]. Allowed range: >=-bWGS.
  | distance | Distance or ground range to the reference point, positive from nadir in the azimuth direction (Earth Fixed CS) [m].
  | losAzRate | Azimuth rate of the LOS (Attitude frame) [deg/s].
  | losElRate | Elevation rate of the LOS (Attitude frame) [deg/s].

void EECFI.Target::targetIncidenceAngle | ( | final SatId | satId,
|  | long | deriv,
|  | double | losAz,
|  | double | incidenceAngle,
|  | double | geodAlt,
|  | double | losAzRate |
| ) |  |  | throws CfiError

It computes the location of a point that is placed on a surface at a certain geodetic altitude over the Earth and that is seen from the satellite on a line of sight that forms a certain azimuth angle in the selected Attitude Frame and that intersects that surface with a certain incidence angle.

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | losAz | Azimuth of the LOS (Attitude frame) [deg]. Allowed range: >=0; <360.
  | incidenceAngle | Incidence angle of the LOS [deg]. Allowed range: >=0; <=90.
  | geodAlt | Geodetic altitude over the Earth [m]. Allowed range: >=-bWGS.
  | losAzRate | Azimuth rate of the LOS (Attitude frame) [deg/s].

void EECFI.Target::targetInter | ( | final SatId | satId,
|  | long | deriv,
|  | long | interFlag,
|  | double | losAz,
|  | double | losEl,
|  | double | geodAlt,
|  | double | losAzRate,
|  | double | losElRate,
|  | long | iray,
|  | double | freq |
| ) |  |  | throws CfiError

Compute the first or the second intersection point of the line of sight from the satellite with a surface located at a certanin geodetic altitude over the Earth.

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | interFlag | Flag for first or second intersection point selection (XPCFI_INTER_1ST or XPCFI_INTER_2ND).
  | losAz | Azimuth of the LOS (Attitude frame) [deg]. Allowed range: >=0; <360.
  | losEl | Elevation of the LOS (Attitude frame) [deg]. Allowed range: >=-90; <=90.
  | geodAlt | Geodetic altitude over the Earth [m]. Allowed range: >=-bWGS.
  | losAzRate | Azimuth rate of the LOS (Attitude frame) [deg/s].
  | losElRate | Elevation rate of the LOS (Attitude frame) [deg/s].
  | iray | Ray tracing model switch (not used).
  | freq | Frequency of the signal [Hz]. Allowed range: >0.

TargetOutput EECFI.Target::targetListInter | ( | final SatId | satId,
|  | long | deriv,
|  | long | interFlag,
|  | final InstrumentData | instrData,
|  | double | geodAlt |
| ) |  |  |

Compute the first or the second intersection point of the line of sight from the satellite with a surface located at a certanin geodetic altitude over the Earth for a set of azimuth/elevation points.

The sets of azimuth and elevation points can be defined in 3 different ways:

- A list of azimuth and elevation pairs.
- A strip of lines of sight, with a fixed azimuth and elevation angles changing with a given step.
- A grid of lines of sight, with both azimuth and elevation angles changing with a given step.

For each pair a user target is computed. To obtain the extra values for all the targets, the methods Target::extraListXXX can be used. The position of the target in output array or vector of these extra methods has the following criterion (note also that Target::extraXXX functions can also be used to obtain results of only one target with the same target numbering criterion, but Target::extraListXXX are optimized to obtain the results for all the targets):

- In case of a list, the index of the list.
- In case of a strip: being n_el the number of elevation values (note that minimum and maximum elevation values are always included in the list):
  n_el=TRUNC((max_elevation-min_elevation)/step_elevation+1)
  The target number is computed in increasing elevation order, from lower to upper elevation:
  - For 0 <= i < n_el-1: target number i corresponds to pair (azimuth, min_elevation + i*step_elevation).
  - For i = n_el-1: target number n_el-1 corresponds to pair (azimuth, max_elevation).
- In case of a grid: being n_el the number of elevation values (note that minimum and maximum elevation values are always included in the list):
  n_el=TRUNC((max_elevation-min_elevation)/step_elevation+1)
  being n_az the number of azimuth values (note that minimum and maximum azimuth values are always included in the list):
  n_az=TRUNC((max_azimuth-min_azimuth)/step_azimuth+1)
  The target number is computed by increasing azimuth and elevation order: from minimum azimuth to maximum azimuth and, for every azimuth value, from minimum elevation to maximum elevation. That is:
  - For 0 <= i < n_el-1: target number i corresponds to pair (min_azimuth, min_elevation + i*step_elevation).
  - For i = n_el-1: target number n_el-1 corresponds to pair (min_azimuth, max_elevation).
  - For n_el <= i < 2*n_el-1 target number i corresponds to pair (min_azimuth + step_azimuth, min_elevation + i*step_elevation).
  ...
  (for 0 <= j < n_az-1 and defining k = i-j*n_el )
  - For j*n_el <= i < (j+1)*n_el-1 target number i corresponds to pair (min_azimuth + j*step_azimuth, min_elevation + k*step_elevation).
  - For i = (j+1)*n_el-1 target number i corresponds to pair (min_azimuth + j*step_azimuth, max_elevation ).
  (for j = n_az-1 and defining k=i-(n_az-1)*n_el)
  - For (n_az-1)*n_el <= i < n_az*n_el-1: target number i corresponds to pair (max_azimuth , min_elevation + k*step_elevation ).
  - For i = n_az*n_el-1 target number i corresponds to pair (max_azimuth , max_elevation)
  Please note the following limitations that will be removed in future releases:
  - The maximum number of intersections with the ellipsoid that can be computed is 30. If this value is exceeded an error is raised.
  - n_az shall be equal to n_el

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | interFlag | Flag for first or second intersection point selection (XPCFI_INTER_1ST or XPCFI_INTER_2ND).
  | instrData | Instrument data.
  | geodAlt | Geodetic altitude over the Earth [m]. Allowed range: >=-bWGS.

Returns:
  Target output information.

void EECFI.Target::targetRange | ( | final SatId | satId,
|  | long | deriv,
|  | double | losAz,
|  | double | range,
|  | double | geodAlt,
|  | double | losAzRate,
|  | double | rangeRate |
| ) |  |  | throws CfiError

It computes the location of a point that is placed on a surface at a certain geodetic altitude over the Earth, that is seen from the satellite on a line of sight that forms a certain azimuth angle in the selected Attitude Frame, and that is at a certain range or slant-range from the satellite.

If the function finds 2 solutions, both are computed and ordered according to the following criterion: the first one will be the one with an elevation closer to 90 degrees (targets will have the same azimuth, equal to input azimuth).

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | losAz | Azimuth of the LOS (Attitude frame) [deg]. Allowed range: >=0; <360.
  | range | Range to the satellite (Earth Fixed CS) [m]. Allowed range: >0.
  | geodAlt | Geodetic altitude over the Earth [m]. Allowed range: >=-bWGS.
  | losAzRate | Azimuth rate of the LOS (Attitude frame) [deg/s].
  | rangeRate | Range rate to the satellite (Earth Fixed CS) [m/s].

void EECFI.Target::targetRangeRate | ( | final SatId | satId,
|  | long | deriv,
|  | double | efRangeRate,
|  | double | range,
|  | double | geodAlt,
|  | double | efRangeRateRate,
|  | double | rangeRate |
| ) |  |  | throws CfiError

It computes the location of a point that is placed on a surface at a certain geodetic altitude over the Earth, that is at a certain range from the satellite, and whose associatedEarth-fixed target has a certain range-rate value.

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | efRangeRate | Range rate of the related Earth-Fixed target (Earth Fixed CS) [m/s].
  | range | Range to the satellite (Earth Fixed CS) [m]. Allowed range: >0.
  | geodAlt | Geodetic altitude over the Earth [m]. Allowed range: >=-bWGS.
  | efRangeRateRate | Range rate rate of the related Earth-Fixed target (Earth Fixed CS) [m/s2].
  | rangeRate | Range rate to the satellite (Earth Fixed CS) [m/s].

void EECFI.Target::targetReflected | ( | final SatId | satId,
|  | long | deriv,
|  | double | geodAlt,
|  | double | deflectionNorth,
|  | double | deflectionEast,
|  | long | sourceType,
|  | double[] | sourceParam |
| ) |  |  | throws CfiError

It allows the user to compute, from S/C position and attitude, and emitting source position, the point of reflection from the source towards the SC at a certain geodetic altitude.

Note: in some limit configurations the function will return a degraded solution (returning also a warning), being 5 milidegrees the maximum difference between the incidence angle and the reflected angle.

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | geodAlt | Geodetic altitude (Earth Fixed CS) [deg]. Allowed range: >=-90; <=90.
  | deflectionNorth | North-South component of the vertical deflection [deg]. Allowed range: >=-90; <=90.
  | deflectionEast | East-West component of the vertical deflection [deg]. Allowed range: >=-90; <=90.
  | sourceType | Type of the source (SourceTypeEnum).
  | sourceParam | Vector with parameters (depends on sourceType). if source_type is XPCFI_SRC_STAR is selected, source_param = [ra (deg), dec (deg), parallax, 0.0, 0.0, 0.0], i.e. star coordinates in BM2000 CS. if source_type is XPCFI_SOURCE_GENERIC source_param = [x, y, z, vx,vy,vz] position and velocity in EF else dummy values. .

native void EECFI.Target.targetSc | ( | final SatId | satId1,
|  | final SatId | satId2,
|  | final Attitude | att2,
|  | long | deriv |
| ) |  |  | throws CfiError

It computes the pointing from one satellite to another satellite.

void EECFI.Target::targetStar | ( | final SatId | satId,
|  | long | deriv,
|  | double | starRa,
|  | double | starDec,
|  | double | starRaRate,
|  | double | starDecRate,
|  | long | iray,
|  | double | freq |
| ) |  |  | throws CfiError

It computes the location of the tangent point over the Earth that is located on the line of sight that points to a star defined by its right ascension and declination coordinates.

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | starRa | Right ascension of the star (True of Date CS) [deg]. Allowed range: >=0; <360.
  | starDec | Declination of the star (True of Date CS) [deg]. Allowed range: >=-90; <=90.
  | starRaRate | Right ascension of the star rate (True of Date CS) [deg/s].
  | starDecRate | Declination of the star rate (True of Date CS) [deg/s].
  | iray | Ray tracing model switch (not used).
  | freq | Frequency of the signal [Hz]. Allowed range: >0.

void EECFI.Target::targetStation | ( | final SatId | satId,
|  | long | deriv,
|  | double | geocLong,
|  | double | geodLat,
|  | double | geodAlt,
|  | double | minLinkEl |
| ) |  |  | throws CfiError

It computes the most relevant observation parameters of the link between the satellite and a ground station.

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | geocLong | GS geocentric longitude (Earth Fixed CS) [deg]. Allowed range: >=0; <360.
  | geodLat | GS geodetic latitude (Earth Fixed CS) [deg]. Allowed range: >=-90; <=90.
  | geodAlt | GS Geodetic altitude (Earth Fixed CS) [m]. Allowed range: >=-bWGS.
  | minLinkEl | GS minimum link elevation (Topocentric CS) [deg]. Allowed range: >=-90; <=90.

void EECFI.Target::targetTangent | ( | final SatId | satId,
|  | long | deriv,
|  | double | losAz,
|  | double | losEl,
|  | double | losAzRate,
|  | double | losElRate,
|  | long | iray,
|  | double | freq |
| ) |  |  | throws CfiError

It computes the location of the tangent point over the Earth that is located on the line of sight defined by an elevation and azimuth angles expressed in the selected Attitude Frame.

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | losAz | Azimuth of the LOS (Attitude frame) [deg]. Allowed range: >=0; <360.
  | losEl | Elevation of the LOS (Attitude frame) [deg]. Allowed range: >=-90; <=90.
  | losAzRate | Azimuth rate of the LOS (Attitude frame) [deg/s].
  | losElRate | Elevation rate of the LOS (Attitude frame) [deg/s].
  | iray | Ray tracing model switch (not used).
  | freq | Frequency of the signal [Hz]. Allowed range: >0.

void EECFI.Target::targetTangentMoon | ( | final SatId | satId,
|  | long | deriv,
|  | long | iray,
|  | double | freq |
| ) |  |  | throws CfiError

It computes the location of the tangent point over the Earth that is located on the line of sight that points to the Moon.

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | iray | Ray tracing model switch (not used).
  | freq | Frequency of the signal [Hz]. Allowed range: >0.

void EECFI.Target::targetTangentSun | ( | final SatId | satId,
|  | long | deriv,
|  | long | iray,
|  | double | freq |
| ) |  |  | throws CfiError

It computes the location of the tangent point over the Earth that is located on the line of sight that points to the Sun.

Note: it can be internally applied a correction to computations in order to compensate for the travel time of light from the Sun to the Earth and the satellites orbiting it. To activate this compensation, the Sun model in xl_model_id must be initialized with the enum XL_MODEL_SUN_TRAVEL_TIME using the function xl_model_init (see [LIBSUM]).

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | iray | Ray tracing model switch (not used).
  | freq | Frequency of the signal [Hz]. Allowed range: >0.

void EECFI.Target::targetTravelTime | ( | final SatId | satId,
|  | long | deriv,
|  | double | losAz,
|  | double | losEl,
|  | double | travelTime,
|  | double | losAzRate,
|  | double | losElRate,
|  | double | travelTimeRate,
|  | long | iray,
|  | double | freq |
| ) |  |  | throws CfiError

It computes the point of the line or sight from the satellite at a given travel time along the line of sight.

Parameters:

  | satId | Satellite id.
  | deriv | Derivative order (DerivPointingEnum).
  | losAz | Azimuth of the LOS (Attitude frame) [deg]. Allowed range: >=0; <360.
  | losEl | Elevation of the LOS (Attitude frame) [deg]. Allowed range: >=-90; <=90.
  | travelTime | Travel time along the (curved) line of sight [s]. Allowed range: >0.
  | losAzRate | Azimuth rate of the LOS (Attitude frame) [deg/s].
  | losElRate | Elevation rate of the LOS (Attitude frame) [deg/s].
  | travelTimeRate | Travel time rate along the (curved) line of sight [s/s].
  | iray | Ray tracing model switch (not used).
  | freq | Frequency of the signal [Hz]. Allowed range: >0.

## Member Data Documentation

long EECFI.Target.numLosTarget

Number of Line Of Sight target calculated.

long EECFI.Target.numUserTarget

Number of user defined targer calculated.