Abstract: A system for monitoring guiding and controlling an unmanned, unteathered flight vehicle, generally assumed to be moving through the earth's atmosphere at a high rate of speed. The system is comprised of on-board positional receiver and processing means coupled to a transceiver capable of combining such positional information with additional data relative to the health and status of the flight vehicle and transmitting the same to a ground station of compatible and simplified design. A preferred positional determination means is to utilize a form for GPS signal thereby affording one the opportunity to include appropriate processing software or additional componentry if necessary for base station purposes and thereby provide a relatively inexpensive system having a low probability of detection for intercept that simultaneously yields vastly improved operating performance characteristics over the mere translation of received GPS signals to down-link or to remote stations as known in the prior art.

Abstract: A global positioning system (GPS) receiver and high accuracy low power time source (HAL) are disclosed. The HAL provides a time source having an accuracy which is high enough for the receiver to achieve fast direct Y-code acquisition. The HAL includes an oscillator adapted to provide an uncompensated frequency signal at a desired frequency. Frequency conversion circuitry receives the uncompensated frequency signal and a control signal as inputs, and provides as an output a compensated frequency signal having an average compensated frequency which is closer to the desired frequency than is the average uncompensated frequency. A temperature sensor provides an output indicative of a temperature of the oscillator. Frequency error determining circuitry determines an error value, as a function of the temperature sensor output, which is indicative of a quantity of frequency error over time in the uncompensated frequency signal.