General Dynamics

About: General Dynamics is a company organization based out in Fairfax, Virginia, United States. It is known for research contribution in the topics: Signal & Propellant. The organization has 5722 authors who have published 5819 publications receiving 85768 citations. The organization is also known as: GD & General Dynamics Corporation.

Adjustable optical fiber grating dispersion compensators

Abstract: Adjustable optical fiber grating dispersion compensators. The invention provides a fully tunable dispersion compensator with a wide dynamic range. Dispersion compensators according to the invention are based on uniform fiber Bragg grating technology. Individual gratings are tuned so that the gratings, which normally operate in reflection mode, operate in transmission mode with the frequency of interest falling just outside a reflection band edge. Gratings are combined to provide broadband, or multiple-wavelength dispersion. Tuning is provided via transducers coupled to the gratings. A control system can be connected to the transducers to provide a control signal so that the frequencies of the gratings can be dynamically tuned. The control system operates by measuring signals from opto-electronic detectors. The signals are used to determine a fractional spectral power transmitted through a filter. The fractional spectral power is related to the amount of dispersion present in the optical path of the network.

Integrated oxygen generation and carbon dioxide absorption method, apparatus and systems

Abstract: A method for producing oxygen and absorbing carbon dioxide in a single operation using a solution that contains an oxygen source and a redox partner that can react to form oxygen and a chemical species that can form an insoluble carbonate to precipitate and chemically store carbon dioxide Carbon dioxide is introduced into the solution and the carbonate precipitates as the oxygen is generated In particular, the invention uses an aqueous solution of permanganate and hydrogen peroxide that react in the presence of a catalyst to produce oxygen and manganese (II) ions Carbon dioxide gas introduced into the solution reacts with the manganese (II) ions to precipitate manganese carbonate Other cations capable of reacting with carbon dioxide to form an insoluble carbonate, for example calcium, barium and magnesium, may also be added to the solution to precipitate carbonate salts Calcium permanganate may used as a source of both calcium and permanganate

Filter/shield for electro-explosive devices

Abstract: An improved electro-explosive squib device is disclosed with filter/shield characteristics rendering the device substantially immune to electromagnetic environments, thus preventing accidental ignition of the squib device. The invention provides for adapting existing squibs or constructing new squibs with immunity to the electromagnetic environments while adding only a minimal amount of material to the device, thus minimizing the possibility of personnel injury caused by debris ejected from rocket propellant ignited by the squib device. These benefits are achieved while maintaining reliability and extended shelf life, and at minimal cost of conversion or manufacture of the squib devices.

Methods and apparatus for generating and communicating wireless signals having pilot signals with variable pilot signal parameters

Abstract: An embodiment for wirelessly communicating a signal includes a transmitter generating and transmitting a wireless signal over a wireless communication channel. The wireless signal includes a guard band, data represented within a plurality of data-bearing subcarriers, and a plurality of pilot signals represented within a plurality of pilot subcarriers. In an embodiment, the plurality of pilot signals have variable pilot signal parameters selected from a group of parameters that includes pilot power and pilot spacing with respect to adjacent pilots. An embodiment further includes a receiver receiving a channel-affected version of the wireless signal, and producing a corrected signal by applying corrections to the received signal based on estimated channel perturbations within the received signal, where the estimated channel perturbations are determined based on the plurality of pilot signals. The receiver also produces an output data symbol from the corrected signal.