Abstract: Improved radar system performance in a jamming environment is achieved by making a complete frequency analysis of the jamming power entering the radar receiver during each range sweep (once per transmitted pulse) and then setting the frequency of the next transmitted pulse to the value which corresponds to the minimum jamming power measured.

Abstract: An interactive game of a strategy nature employing a digital processor includes a keyboard to preselect the successive directional movements of one or more of the simulated player symbols prior to the start of the game and/or supplement this preprogrammed game action with real-time control over further game action during the playing of the game.

Abstract: An eye-safe laser cloud height rangefinder comprising an Er:LiYF.sub.4 laser operating at 1.73 .mu.m and a germanium detector.

Abstract: Apparatus for generating and controlling the position of a displayed symbol for a video game comprises a plurality of voltage comparators responsive to inputs thereto from multiple control voltage sources including a microprocessor and a participant control such that the microprocessor and participant control introduce separate bias offset voltages into the comparators to occasion positioning of the displayed symbol in accordance with the net effect of the multiple inputs.

Abstract: Apparatus and methods are disclosed herein for use in conjunction with raster scan video displays, including standard monochrome and color television receivers, for the generation, display and manipulation of images upon the screen of a display for the purpose of playing games or for the purpose of drawing pictures. In addition to the generation of signals which, when supplied to the video display, cause the display of moveable and immoveable game playing indicia such as walls, players, and balls to play a variety of typical games such as tennis, handball, billiards, and the like, in a manner well known in the art, other indicia are displayed on the display screen in response to commands from the game operator which are defined by the operator as to shape, location, color and other attributes and are, furthermore, endorsed with interactive characteristics.

Abstract: Improved laser system gain is achieved by using Gadolinium to totally replace the Yttrium in a Lithium Yttrium Fluoride (YLF) host crystal so as to increase the amount of Neodymium which can be doped into the host crystal.

Abstract: Transmission of digital information during the course of a television signal transmission is provided by transmitting a predetermined number of color burst cycles during the horizontal blanking interval such that logical bits are represented by different, predetermined cycles of color burst.

Abstract: There is herein disclosed a laser detector and spectral analyzer comprising a plurality of photoelectric detector elements, at least, two of which are suitably masked and disposed behind a wedge type interference filter. An additional detector element is operated without any mask or filter. The detector output signals are electronically processed to provide a substantially instantaneous and independent indication of the mean spectral wavelength, spectral width, total power and pulse length of radiant energy incident upon the apparatus.

Abstract: Synchronization of a source of computer controlled video to another video source is achieved by providing clock pulses for the source of computer controlled video at some multiple of the horizontal synchronization frequency of the other video source to obtain frequency coherence and by detecting phase incoherence between the signals from the two sources and in response thereto causing the clock pulses to cease for a predetermined period to allow the source of computer controlled video to "slip" sync to obtain phase coherence.

Abstract: Instant replay for microprocessor-controlled video games is provided by storing and retaining for a period of time in a random access memory the results of microprocessor polling of each of the player command entry devices. In a memory conserving embodiment only newly entered player commands and the times when such commands are entered need be stored and retained.

Abstract: A system for locating man-made specularly reflecting objects amongst non-specular surroundings such as foliage includes apparatus to initially project orthogonally polarized laser pulses towards a given area and to then detect returned laser pulses which are polarized, while rejecting randomly polarized radiation returned from non-specular objects. In one embodiment, specularly reflecting objects are detected by providing two detectors, each sensitive to light of a different polarization, and by differentially summing their outputs to reject randomly polarized incident light.

Abstract: A laser system for generating two closely spaced in time laser pulses where each pulse is a different color comprises a first and second optical cavity with a common optical leg containing a laser rod capable of emitting light of two polarities along an axis and a polarizing beam-splitter positioned at the common junction of the two cavities for splitting the radiation impinging thereon according to polarity and propagating it into the noncommon sections of the first and second optical cavities each of which contains a Q-switch. The output from the cavities is taken at the polarizing beam-splitter and comprises two closely spaced in time pulses of different polarity. The two pulses are applied to a doubler crystal such that pulses of one polarity are doubled while pulses of the other polarity are unchanged.

Abstract: Captioning of television presentations is achieved by transmitting digital data superimposed on the normal FM sound signal by modulation of an ultrasonic subcarrier and receiving the digital data at a viewer's television receiver by picking up the ultrasonic signal from the television receiver's loudspeaker; the received digital data being demodulated and applied to the television receiver as readable alphanumeric captions.

Abstract: An aquaculture rearing system for improving space utilization and yield is disclosed in which clustered, vertical rearing tanks are provided with individual stacked habitats in the form of baskets attached to a strongback member which houses a removable feeding rod, in which the baskets are quickly detachable through the use of interlocking detents and in which nestable baskets are utilized for different sized animals. Progressive space increments to match growth are provided by two different size baskets and removable dividers. Overflow water is skimmed by a skimmer which surrounds the entire top of each tank to prevent bacteriologic contamination of the water within the tank. The staggered modular mounting produces a tripod-like stability even though each tank has a single leg, and provides visibility and density. An overhead materials handling system is used in which the animals are protected by a fog to prevent gill malfunction.

Abstract: A highly efficient, open-ended solar energy receiver is disclosed having a porous element through which air passes and a conventional heat exchanger positioned above and immediately adjacent to the porous element such that when solar energy is focused onto the porous element, a constant controlled temperature hot air stream from the element is conveyed by the temperature controlled convectively rising hot air to the conventional heat exchanger to produce steam, thereby minimizing pumping requirements. The quantity of air flowing through the receiver is regulated, if desired, by a low-power exhaust fan operating at a relatively low temperature due to the removal of heat by the heat exchanger. Regulation may also be obtained by an opening at the top of the receiver, controlled in such a manner as to vary the air flow through the system to maintain a constant temperature output from the heat exchanger. Additionally, if desired, water flow control may be utilized to maintain the proper energy balance.

Abstract: A resistive heater comprising an emitter, including a hot zone center section and lower temperature end sections, disposed within a protective tube with the emitter and protective tube being mounted within end caps with a spring mechanism provided to allow for the difference in expansion and contraction of the emitter and protective tube during heating and cooling.

Abstract: A wide field of view-narrow band detection system including a radiation responsive member and optical filter is provided by employing optimal angle cones to simultaneously control field of view, throughput and angles impinging on the optical filter.

Abstract: A processor is provided for an inertial measurement unit which computes its angular velocity and translational acceleration in terms of dynamic variables chosen because they uniquely define the motion of the inertial measurement unit in terms of linear combinations of the outputs of the transducers used in the inertial measurement unit. In one embodiment, the processor includes a demodulator for obtaining d.c., in-phase and quadrature sets of signals from the outputs of the transducers, a combining circuit for deriving some of the dynamic variables from the in-phase and quadrature sets of signals, and a microprocessor for transforming the dynamic variables into angular velocity and translational acceleration vectors. The processor is used with a small rugged, precise inertial measurement unit in which vector components are measured by the use of accelerometers fixed in a spinning rotor, at least one of which is off-set from the rotor axis and has a sensitive axis parallel to that of the rotor.

Abstract: An efficient split cycle solar energy conversion system utilizes sensible heat storage to isolate a solar receiver loop from a Brayton cycle engine loop. In this system a sensible heat storage unit is first charged by the solar receiver, is then switched to the inlet to the Brayton cycle turbine where it is discharged, and finally may be utilized as a high temperature, high effectiveness recuperator to recapture waste heat from the Brayton cycle turbine. With high effectiveness sensible heat storage recuperation, the Brayton cycle engine runs at extremely high efficiency. Moreover, since these storage devices can be run efficiently at low gas velocity, and since recuperated Brayton cycle engines become very efficient at extremely low pressure ratios, an overall thermal/electric conversion efficiency in excess of 60% can be obtained.

Abstract: An aquaculture habitat is described for the rearing of post larval crustacia in which a cellular honeycomb structure, preferably of opposed cones, provides compartments for the animals and serves as the domicile core. Individual animals are inserted into the core compartments and the core is sealed with a screen or a mesh on either side of the core. The screen or mesh is of a size such that water and food may pass through but which restrains the animals. Cores with screens in place are vertically oriented and horizontally stacked on a false bottom within a tank of water. The tank is provided with food distribution means adjacent the false bottom, and air lift circulation means beneath the food distribution means which, due to the upward rise of the expanding air bubbles, moves the food and freshly filtered and aerated water to the vicinity of the habitats.