Light Time Delay Options

You can set parameters related to light time delay and signal path for new spatial condition calculations.

For a discussion of light time computation, including terminology and equations, see: Light Time Delay (PDF).

Option Description
Use Light Time Delay Choose whether to consider light time delay in access computations. When light time delay is not considered, aberration is ignored also.
Light Time Delay Convergence This option sets the tolerance used when iterating to determine the light time delay. The iteration stops when the improvement in the value is less than this tolerance.
Aberration Type This option sets the model of aberration to be used in access computations. The values are:
  • None. Ignores aberration.
  • Annual. Considers annual aberration only. Thus, aberration is applied only in cases where the light time delay is computed using the solar system barycenter frame.
  • Total. Applies the full aberration correction, when light time delay is computed.
Signal Path Clock Host Time values are reported with a clock colocated with the clock host object.
  • Base: Refers to the object that brought up the Access Tool.
  • Target: Refers to an object from the Associated Objects list.
Signal Sense of Clock Host Allows you to set the direction of the signal.
  • Transmit: The signal is being sent from the object you selected as the Clock Host.
  • Receive: The signal is being received by the object you selected as the Clock Host.

If Use Default Clock Host and Signal Sense is disabled and a Bistatic Receiver Radar or Bistatic Transmitter Radar is selected as the Clock Host, this option is automatically set to the direction of the Radar and cannot be changed.