Abstract: An apparatus and method for controlling the communication frequencies of a software controlled radio by using GPS to calibrate one or more local oscillators and compensating within the digital radio processing for the local oscillator inaccuracies. The apparatus and method receives and transmits radio frequency signals and includes an oscillator; a frequency monitor adapted to measure the frequency of the oscillator; a numerically controlled oscillator; and a computer adapted to receive the frequency measurement of the oscillator from the frequency monitor, to calculate an error associated with the oscillator, and to calculate a numerically controlled oscillator setting based on the calculation of the error associated with the oscillator; the numerically controlled oscillator adapted to receive the numerically controlled oscillator setting from the computer.

Abstract: An apparatus and method for controlling the communication frequencies of a software controlled radio by using GPS to calibrate one or more local oscillators and compensating within the digital radio processing for the local oscillator inaccuracies.

Abstract: An apparatus and method for using GPS uses a radiation tolerant executive module to monitor and reinitialize a GPS module. The GPS module can reload information from a radiation tolerant memory when it is reinitialized. The radiation tolerant executive module also can direct a first GPS module having a first clock generator and a second GPS module having a second clock generator to use a clock signal from one of the first clock generator and the second clock generator. The radiation tolerant executive module also may be used to direct a first GPS module having a first clock generator and a second GPS module having a second clock generator to phase lock the first clock generator to the second clock generator.