Abstract: A system carried on a satellite in orbit around the earth is configured to detect an object on a collision or near collision course with the satellite, to determine that the object is a hostile attacker and, if so, to timely deploy one or more countermeasures to defeat, deflect, or destroy such an attacker autonomously.

Abstract: An autonomous system for a satellite which calculates collision paths of debris from anywhere within the spheroid around the satellite by using its radar/ladar data and from data on its own orbit derived by onboard sensors such as star, earth and sun sensors or from stored data sent from its ground control station through the satellite's command subsystem. If a collision would be likely, the system calculates the minimum change in the satellite's orbit to avoid such collision and generates and executes commands for firing on-board orbital control thrusters to put the satellite in a suitable avoidance orbit.

Abstract: An autonomous system for a satellite which calculates collision paths of debris from anywhere within the spheroid around the satellite by using its radar/ladar data and from data on its own orbit derived by onboard sensors such as star, earth and sun sensors or from stored data sent from its ground control station through the satellite's command subsystem. If a collision would be likely, the system calculates the minimum change in the satellite's orbit to avoid such collision and generates and executes commands for firing on-board orbital control thrusters to put the satellite in a suitable avoidance orbit.

Abstract: A modulator includes input paths for audio information from an electronic audio channel; output paths for transmitting said audio information over a frequency-modulated radio frequency signal to a FM broadcast receiver; and one or more programs for measuring or estimating the spectrum environment of the frequency-modulated RF signal bearing the audio information through sampling and analysis to select an optimum radio signal level and signal transmission mode for transmission to the FM receiver in a near interference free manner.