Abstract: A hardware logic network, operating at real-time data rates, generates a signal which matches the Mth-largest signal of an input data set. To accomplish this signal-matching, the network utilizes an iterative series of value adjustments which cause an intermediate working quantity to converge to a number whose rank in comparison to the input set is the same as that of the true Mth-largest. When test comparisons indicate that the intermediate value's relative rank is too low, the value-adjustment is upward. The adjustment is downward otherwise. Operating upon input data whose range of possible values is limited to a predetermined interval, the system takes as its initial working quantity the midpoint of this interval. The magnitude of the first adjustment is one-half of the remaining interval on either side of the initial approximation. Subsequent magnitude adjustments are in turn one-half of the preceeding half-remaining-interval magnitude.

Abstract: An improved laser power supply is disclosed. The invention is designed to provide the high electric field required for starting a laser in addition to the capability of automatically readjusting after laser action is initiated to provide an optimum impedance match for high efficiency energy transfer. The invention includes variable means for matching the impedance of a laser cavity with a source of RF energy. In addition, means are provided for sensing a change in the impedance of the laser cavity. The sensed change is then utilized to vary the impedance of the matching elements to provide and maintain an optimal coupling between the laser cavity and the RF source.

Abstract: Apparatus for controlling the pointing position of the payload platform of a dual-spin satellite. A torque motor which controls the relative position of the payload platform is controlled by means of a closed-loop feedback system which points the line-of-sight of the platform at a predetermined position on the earth. The control circuitry comprises position and rate sensing devices which monitor the relative position of the line-of-sight and the relative rotational rate of the payload platform. The line-of-sight of the platform is compared to signals indicative of the angular subtense of the earth. If the line-of-sight is pointed at the earth, then position command signals control the torque motor. If, however, the line-of-sight of the platform is not directed at the earth, then rate command signals are summed with the position command signals and subsequently applied to the motor.

Abstract: The invention includes a first switching transistor which is actuated by a logic signal. This switching transistor is disposed in a current path from the base of the power transistor. When this switch is actuated, the invention provides a large steady state base drive current superimposed with a base current peaking pulse from a current generator. The invention also includes a second switch which applies a reverse potential to the base of the switching transistor for fast turnoff. The specific embodiments disclose circuitry for regulating forward base drive current to minimize line voltage variations and component tolerances. An improved bipolar power transistor base drive circuit for switching regulator and DC to DC converter power supplies is disclosed.

Abstract: Apparatus for processing microwave signals at two predetermined frequencies. Signals at a first predetermined frequency are received or transmitted at one end (input port) of a microwave transmission line whose other end is utilized as a common output port for transmitting and receiving signals at both predetermined frequencies. A band rejection portion is provided which comprises first and second rejection resonators orthogonally disposed along the transmission line at two predetermined positions. A bandpass portion, comprised of a plurality of collinearly aligned bandpass resonators, is disposed at a third predetermined position along the transmission line. Signals at a second predetermined frequency are transmitted or received at a second input port which is part of the bandpass portion. All resonators are capacitively coupled together and to the transmission line.

Abstract: A circuit is disclosed which provides overcurrent protection for switching regulator power supplies with soft start and soft turn OFF features. The invention includes first means for sensing the current through the switching transistor of the regulator and second means for providing a voltage signal to the switching transistor deactivation circuitry whenever the current through the switching transistor exceeds a predetermined threshold. In a specific embodiment, the current generator is provided by a transistor biased for nominal operation in its active mode. The means for sensing the current through the switching transistor is provided by a resistor the voltage drop across which provides the input voltage threshold to the bipolar transistor current generator. The current generated by the transistor causes a voltage to quickly develop across an RC network referenced to ground potential.

Abstract: An adaptive comparator is provided which compares a signal from a horizon sensor of a satellite to a predetermined threshold to provide a signal indicative of the relative position of a celestial body with improved noise immunity. When the comparator receives a signal from the horizon sensor which exceeds the threshold, an output is provided which may be used to change the orientation of the spacecraft. The comparator includes circuitry for ascertaining the average of one or more of the most recent input pulses which exceeded the previous threshold. This average is then utilized to set a new or adapted threshold. The subsequent input signal is then compared to the adapted threshold and the recursive process continues.

Abstract: An improved line-of-sight commanded missile guidance system is provided which provides the operator of a missile system with the capability of hitting targets which would otherwise be obscured by darkness, smoke, aerosols or poor atmospheric visibility.The system includes a tracker equipped with an infrared sensor and means for periodically blinking a laser beacon which is mounted on the missile. The laser operates in a range in which it would be most visible under the above described atmospheric conditions. Blinking provides countermeasure resistance. The sensor provides electrical signals representing frames of data corresponding to the target scene. Alternate frames contain the beacon signature. Electronic circuitry is provided for subtracting successive frames to eliminate clutter and to then provide signals indicative of the position of the missile relative to the center of the field of view.