Abstract: In a method and system for locating an unknown transmitter which emits an interfering signal, multiple signals, including a phase-calibrating signal and the interfering signal, are simultaneously observed within a passband. These signals are then simultaneously cross-correlated. The phase-calibrating signal is then isolated from the cross-correlated signals and processed to determine an amount of offset to compensate for frequency fluctuations between local oscillators in satellites, which receive and retransmit the phase-calibrating signal and the interfering signal.

Abstract: A satellite tracking system, including a terrestrial transmitter, a plurality of terrestrial receivers, and a controller/analyzer, operates in two modes. In an active mode, the transmitter emits a tracking signal within a spread spectrum to a satellite and at least one of the receivers receives the signal retransmitted by the satellite. The controller/analyzer then determines the satellite position and velocity from the received signal. In a passive mode, at least two receivers each receive a signal transmitted from the satellite during normal operation and the controller/analyzer determines the satellite position and velocity from the received signals. The satellite position and velocity can be used to determine the position of an unknown transmitter that causes interference at the satellite.

Abstract: A low areal density protective shield apparatus, and method for making same, for protecting spacecraft structures from impact with hypervelocity objects, including a bumper member comprising a bumper ceramic layer, a bumper shock attenuator layer, and a bumper confining layer. The bumper ceramic layer can be SiC or B.sub.4 C; the bumper shock attenuator layer can be zirconia felt; and the bumper confining layer can be aluminum. A base armor member can be spaced from the bumper member and a ceramic fiber-based curtain can be positioned between the bumper and base armor members.