SEARCH · Engineering Papers
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Feasibility of computer prediction of broadband near-field electromagnetic interference in space vehicles
Power response of two-element interference frequency correlation interferometer to point source of broadband random noise
Broadband low drive power electro-optic laser beam optical intensity modulator design and test results
Multimode waveguide excitation analysis for broadband operation of low noise antenna feeds
Broadband chokes and absorbers to reduce spurious radiation patterns of antenna array caused by support structures
Calorimetric measurement of source and broadband spectral absorptances of spacecraft thermal control coatings during exposure to UV in vacuum environment
Aerodynamic broadband noise mechanism applicable to axial compressors
Broadband frequency discriminator with resistive captive inductive networks
Broadband microwave waveguide window to compensate dielectric material filling
Comb type traveling wave maser amplifier for improved high gain broadband output
Broadband modified turnstile antenna for use in space tracking and communications
Solid state broadband stable power amplifier
Broadband distribution amplifier with complementary pair transistor output stages
Segmented superconducting magnet producing staggered magnetic field and suitable for broadband traveling wave masers
It is shown that a simple metal-dielectric-metal filter for broadband ultraviolet (BUV) reflectance control can provide a stable and effective means for reducing stray visible radiation in UV reflective optical systems. The application of such a filter in a BUV instrument resulted in a reduction of scattered visible light by at least an order of magnitude. The instrument has been in orbit for 2.5 year without loss of sensitivity or an increase in scattered light background.-
Recent theoretical work on sound sources in subsonic turbomachinery is applied to the correlation of axial-flow fan and compressor noise measurements. Correlations are presented for directivity and sound-power spectra associated with broadband noise. A simple explanation is given to account for the relative amounts of sound power transmitted upstream and downstream from a single-stage fan.
On May 28, 1974, a photographic mission from 5.3 kilometers altitude was flown over the James River from Norfolk to Hopewell. During the mission 252 photographs were exposed over the river. The photographs are divided into four simultaneously exposed groups with each group exposed through a different broadband optical filter. The four filters isolated blue-green, green, yellow, and near-infrared radiation from the water body. The document summarizes the mission photography in relation to flight altitude, sunglint, and photographic exposure.
A broadband constant law detector was developed for precision power measurements, radio metric measurements, and other applications. It has a wide dynamic range and an accurate square law response. Other desirable characteristics, which are all included in a single compact unit, are: (1) high-level dc output with immunity to ground loop problems; (2) fast response times; (3) ability to insert known time constants; and (4) good thermal stability. The detector and its performance are described in detail. The detector can be operated in a programmable system with a ten-fold increase in accuracy. The use and performance of the detector in a noise-adding radiometer system is also discussed.