Sam Deadrick

While working as a software engineer at a satellite systems company, I developed a tool that simulates observations of satellites made by various kinds of sensors:

Inputs

• satellite
  • position and velocity in ECI coordinates
  • average surface area
  • coefficient of reflectivity
• sensor
  • latitude, longitude, and altitude for ground-based sensor
  • position and velocity in ECI coordinates for space-based sensor
  • frame type (true of date, mean of date, J2000)
  • Field of view
  • if radar:
    • pulse number (for coherent integration)
    • system temperature
    • range extent
    • power
    • transmitter gain
    • wavelength
    • frequency
  • if optical:
    • iFOV
    • minimum visual magnitude

Outputs

• observations of satellites
• explanations of why sensors would not have made some observations of objects they were told to watch
• plots showing times at which sensors could not observe satellites

Types of Phenomena Modeled

• The field of view of the sensor
• Obstructions to the line of sight between the sensor and the target
• An eclipse of a satellite caused by the Earth
• The visual magnitude (brightness) of the satellite
• The radar cross section of a satellite
• The minimum resolvable angle of an optical sensor
• The time delay between a target being at an observed position and the observation reaching the sensor
• The latency between a sensor making an observation and the observation reaching the sensor operator
• The pointing error for passive sensors
• The pointing, range, and range rate error for active sensors
• Minimum elevation of ground-based sensors

Algorithm Document