Antennas

With a satellite or GPS receiver highlighted in the Object Browser, click the button or select Antenna from the Object Catalog to attach an antenna to the satellite or GPS receiver. The following properties can be specified for an antenna:

Antenna Properties
Property Description
PhaseCenterLocation Space-based only. Offset of the antenna phase center from the satellite's center of gravity in the satellite's body frame. Specify the X, Y and Z coordinates in the selected distance unit.
PhaseCenterLocation.Estimate

Applies only to an antenna on a satellite-based GPS receiver. Set to true to estimate antenna phase center location in the filter and smoother or to randomly deviate in the simulator. A single phase center is used for both carrier phase and pseudo-range measurements. Estimation of phase center is currently supported when using carrier phase, pseudo-range observations, and GNSS navigation solution measurements.

Use the SigmaX, SigmaY and SigmaZ attributes to specify a priori position uncertainty in the respective directions of the satellite body frame.

Boresight For an antenna attached to a space-based GPS receiver only. Identifies the reference direction to measure elevation from the user to the GPS spacecraft. Use the elevation and azimuth fields to specify the direction of the antenna boresight in the spacecraft body frame. An elevation of 90 degrees specifies an antenna boresight along the body fixed Z axis and azimuth is measured from the body fixed X axis positive in the direction of the body fixed Y axis. The MinElevation is used to specify a minimum elevation of the vector from the antenna to the GPS satellite with respect to the specified antenna boresight direction. The antenna to GPS vector has an elevation angle of 90 degrees with respect to the boresight direction when it is collinear with the boresight direction.
AntennaOffsets Applies only to an antenna on a facility-based GPS receiver. Offset of the antenna phase center location from the Facility.Position may be specified in either Earth Centered Fixed (ECF) coordinates or in Height, and horizontal (East, North) eccentricity. If in ECF coordinates, specify the X, Y and Z offsets in the selected distance unit. If in H/E/N, specify the Height, East, and North offsets in the selected distance unit.
AntennaID Enter an integer greater than zero.

ODTK 6.5