Abstract: Methods and apparatus are provided for distributed polyphase spread spectrum communication and non-contiguous spectrum underlay. The method includes polyphase channelizing a direct sequence spread spectrum (DSSS) signal, determining available spectrum in an observed frequency range having a noise floor based on detection of polyphase users below the noise floor, distributing the polyphase channelized signal among the available spectrum, and interference mitigation using a combination of standard signal detection and cyclostationary feature detection methods.

Abstract: Methods and apparatus are provided for coupling a satellite to an earth terminal. The apparatus inputs of the satellite that is configured to receive digital uplink signals, an autoscaling digital multiplexer of the satellite that is configured to digitally multiplex the digital uplink signals to produce a digital composite signal, and a digital modulator of the satellite that is configured to digitally modulate the digital composite signal to produce a digitally modulated composite signal. In addition, the apparatus comprises an input of the earth terminal that configured to receive the digitally modulated composite signal and a digital demodulator of the earth terminal that is configured to digitally demodulate the digitally modulated composite signal received by the input of the earth terminal to produce a second digital composite signal.

Abstract: Methods and apparatus are provided for coupling an earth terminal to a satellite The apparatus comprises multiple inputs of the earth terminal configured to receive multiple digital communication signals, a autoscaling digital multiplexer of the earth terminal configured to digitally multiplex the multiple digital communication signals to produce a digital composite signal, and a digital modulator of the earth terminal configured to digitally modulate the digital composite signal to produce a digitally modulated composite signal. In addition, the apparatus comprises an input of the satellite configured to receive the digitally modulated composite signal, and a digital demodulator of the satellite configured to digitally demodulate the digitally modulated composite signal received by the input of the satellite to produce a second digital composite signal.

Abstract: The present invention provides a network connectivity system and method that facilitate the design of a network connectivity plan where the availability of link resources is limited and varies with the time. The preferred system and methods can be used to provide a network connection plan that fully connects such a network, where possible, while efficiently allocating the link resources used to implement the network connection plan. The network connectivity system and method develops the network connection plan by choosing links based on link resource availability and link duration. Thus, the network connectivity system and method creates a connection plan that, if possible, keeps full connectivity in the network, compensating for changes over time in the availability of links. The network connectivity system thus provides the ability to efficiently connect dynamic networks in a way that facilitates the routing of data to between nodes in the communication network.

Abstract: Methods and apparatus are provided for generating for generating a multiplexed communication signal in a wireless communication system. The apparatus comprises inputs configured to receive digital communication signals, a transform matrix configured to transform the digital communication signals into transformed digital communication signals, and a processor configured to generate a scaling vector for the transformed digital communication signals. Furthermore, the apparatus further comprises an operator configured to produce a mantissa for each of the transformed digital communication signals with the scaling vector and a multiplexer configured to multiplex the mantissa for each of the transformed digital communication signals and the scaling vector to produce the multiplexed communication signal.

Abstract: Disclosed is a method and apparatus for improving airborne vehicle tracking and guidance systems by reducing boresight error induced by polarization of the RF energy impinging on the vehicle radome. The radome wall is formed with a taper which gradually increases from the base near the vehicle antenna to the tip according to a disclosed formula which accounts for frequency, incidence angle, look angle, and the dielectric constant of the radome material. This taper of the radome minimizes the crossplane boresight error component magnitude which is polarization sensitive and produces a polarization insensitive inplane boresight error component. Also disclosed is a method of electronically compensating such radomes for boresight error where the radome boresight error data accumulated during testing is digitized and processed for compensating data in the vehicle electronic system to provide compensated tracking data for the vehicle guidance system.

Abstract: In the particular embodiment of the invention described herein, sonar signals in the range from 200-3600 cps. are analyzed by bandshifting selected segments of 100 cps. width to the range 300-400 cps. for analysis, and indications of signals in all of the bands are presented side-by-side on a continuous printer. in addition, the modulation envelope of the detected signal, which contains low frequency modulation components, is demodulated to provide indications of such low frequency components in a target signal.

Abstract: An emergency power generation system mounted in the aft portion of a submarine includes a gas turbine arranged to drive a generator and an exhaust gas outlet in the rudder structure of the submarine to reduce submarine construction cost and avoid contamination of the fresh air supply for the submarine.

Abstract: A submarine arrangement comprising a double hull construction forward having a wasp waist section minimizes ship displacement and permits storage of weapons in the wasp waist section.

Abstract: A linear actuated sealant applicator pump for pumping a sealant into an aperture prior to installation of a fastener in that aperture. An air driven linear actuator translates a cam plate carrying a sealant applicator head from a first position in a first direction spaced from and slightly out of vertical alignment with the aperture to which sealant is to be applied. An adjustable stop limits the translation of the cam plate and injector pump. The actuator then continues in the first direction causing the cam plate to follow a cam slot translating the sealant applicator head in a second direction normal to the first direction toward and in vertical alignment with the aperture with the head engaging the edges of the aperture. The engagement of the head with the edges of the aperture prevents further translation of the sealant applicator head into the aperture.

Abstract: Highly efficient reflective optical system that perfectly reflects incident electromagnetic radiation of a certain spectra and almost perfectly reflects radiation of another spectra. Incident electromagnetic radiation having a wavelength above a critical wavelength is relatively perfectly reflected. The critical wavelength is determined by the critical temperature of a high temperature superconductor material incorporated in the optical system. A preferred embodiment includes a cryogenically cooled substrate to which is applied a coating of a noble metal such as silver. A layer of a high temperature superconductor material is applied over the coating of noble metal. Since the critical wavelength of the incident radiation is inversely proportional to the critical temperature of the superconducting material, the use of high temperature superconductor material in the optical system provides a critical wavelength whereby certain spectra of an incident radiation is perfectly reflected.

Abstract: A method and apparatus for correcting harmonics (multipoles) in high energy particle accelerators using superconducting magnets using a pattern of superconducting bands adjacent to the accelerator magnets. In such accelerators, superconducting coils are positioned around a non-magnetic beam tube with the magnetic coils designed to guide particles, such as protons, along the tube. Magnetic field non-uniformities in the form of multipole harmonics will disrupt the beam guidance, causing particles to hit the tube walls and be lost, reducing accelerator efficiency. The negative effects of multipoles (harmonics) in such accelerators can be reduced or eliminated by positioning a non-magnetic tube bearing a pattern of longitudinal superconducting bands, connected by circumferential band segments around the exterior of the helium vessel or other suitable surface near the magnet ends. The bands are formed from a superconductor having a critical temperature above the boiling temperature of liquid nitrogen.

Abstract: A method of manufacturing a fiber reinforced, resin matrix, tank with an integral fitting, such as an internally threaded pipe connection, bulkhead door or manhole entryway. A thread form tool having a cylindrical bore and a rounded pattern thread forming outer surface at one end is provided. The tool is secured to a drive shaft extending through the tank forming mandrel with the thread forming end adjacent to the mandrel. A second, thread is formed on the opposite end of the threat form tool opposite the tank mandrel and carries a consolidation nut. A consolidation washer rides on a wider cylinder surface of the thread form tool intermediate the two threaded ends. At least one fabric doily or band is placed over the thread forming tool rounded threads and the tank mandrel is filament wound with high strength fibers impregnated with a resin in a conventional manner, with filaments overlapping the rounded thread area.

Abstract: A fail-safe circuit for preventing an inadvertent communication of a signal from an input terminal to an output terminal includes a series switching network electrically connected between the input terminal and the output terminal. The series switching network contains two switching circuits electrically connected in series. One switching circuit is an electrical switching circuit and the other is an electromechanical switching circuit. The switching circuits are chosen such that defects causing the electrical switching circuit to short circuit do not affect the electromechanical switching circuit and defects causing the electromechanical switching circuit to short circuit do not affect the electrical switching circuit. The fail-safe circuit also includes circuitry for preventing inadvertent communication of the signal from the input terminal through the series switching network to the output terminal when one of the switching circuits is in a short circuited state or condition.

Abstract: An arrangement for attaching and quickly disconnecting and jettisoning a rocket booster from a core space vehicle. The arrangement includes a housing connected at one end to the booster and a segmented nut carried within the housing that threadedly engages a bolt end of an interface mounting clevis secured to the space vehicle. A retainer both locks the segmented nut on the bolt and is responsive to high pressure fluid to slide out of locking engagement with the nut and to urge a conically shaped wedge into a shaped end of the segmented nut to force the segments outwardly out of threaded engagement with the bolt end to disconnect the booster from the space vehicle. High pressure fluid is also applied to a piston having a plunger in engagement with the bolt end so that the bolt end is swiftly driven out of the housing and the booster is thereby jettisoned form the space vehicle. The high pressure fluid is preferably provided by a pyrotechnic device.

Abstract: A persistent switch system for protecting a large superconducting magnet coil during quench while providing the necessary different resistances needed for operation of the system in coil charging, discharging, persistent and quench modes while minimizing the heat load on the system refrigerator. The system includes a circuit having a combined persistent switch and shunt heater coil using two superconductor coils in parallel with a normal resistive thermal shunt coil thermally linked to the superconducting magnet coil. Switch superconducting coils can be driven normal to provide the switch resistance needed for efficient charging/discharging or the resistance needed to drive sufficient current through the shunt resistor coil during a quench. The quench operation uses shunt coil heating to enhance normal zone growth in the main coil, limiting the maximum quench temperatures reached.

Abstract: A combined application paraboloid spacecraft structure that is adapted to serve as a structural element for space transportation vehicles, and in additional applications, as a separated spacecraft. The primary structure of the combined application paraboloid spacecraft structure is shaped as the shell of a paraboloid of revolution which has focusing properties for use in such functions as a solar power concentrator, a surveillance or an astronomical telescope, or a communications antenna when deployed in space. The primary structure of this combined application paraboloid can nest and can also be used to support other single or multiple host spacecraft during launch and orbit to orbit transportation.

Abstract: A self supporting solar concentrator cell array adapted for use in space applications that includes a plurality of cylindric parabolic reflective mirror surfaces, each of which focus recipient sunlight forwardly onto a focal line which is positioned approximately on the backside of an adjacent mirror surface on which is secured a solar element for converting the focussed sunlight into electricity. A front element extending upwardly from the leading edge of each mirror surface cooperates in providing an aperture through which the focussed sunlight passes and side elements close each cell element. The backside of each mirror is provided with a thermally emissive surface to provide mirror thermal control and allows the mirror to act as a thermal radiator fin for the solar cell elements. The mirror surface is provided with a highly reflective coating such as aluminum or silver to optimize reflectivity.

Abstract: A rocket engine protection system for a recoverable rocket booster which is arranged to land in a salt water body for recovery. The system includes an inflatable water impermeable elastomeric bladder that may be fabricated of a silicone impregnated woven Kevlar material and which is stowed in a deflated condition on a rotatable arm that is journalled to the lower portion of the nozzle of a liquid rocket booster. The deflated bladder and the rotatable arm are protected by a pod cover that is hinged to the outer portion on the nozzle. During the controlled descent of the liquid rocket booster by parachute for landing in a salt water body the pod cover is released and opened upwardly by a gas cylinder actuator. The rotatable arm which is biased by a torsion spring is then permitted to rotate around to position the deflated bladder in a deployed position within the interior of the lower portion of the nozzle. The bladder is then inflated to form a plug within the nozzle.

Abstract: A rocket engine protection system for a recoverable rocket booster which is arranged to land in a salt water body in substantially a nose down attitude. The system includes an inflatable bag which is stowed on a portion of a flat annular rim of the aft skirt of the booster. The bag is hinged at opposing sides and is provided with springs that urge the bag open. The bag is latched in a stowed position during launch and prior to landing for recovery is unlatched to permit the bag to be urged open and into sealing engagement with the rim. A source of pressurized gas further inflates the bag and urges it into sealing engagement with the rim of the skirt where it is locked into position. The gas provides a positive pressure upon the interior of the bag to preclude entry of salt water into the skirt and into contact with the engine. A flotation arrangement may assist in precluding the skirt of the booster from becoming submerged.