On the use of an array of circumferential slots on a large cylinder as an omnidirectional antenna.
Array of circumferential slots on large cylinder as omnidirectional antenna
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Array of circumferential slots on large cylinder as omnidirectional antenna
Method of compensating for effects of slot in rectangular waveguide
Complementary slot-dipole antenna with hemispherical coverage for use in passive interferometer beacon acquisition system
Free molecule flow and surface diffusion through tubes and two-dimensional slots
Diode-iris controlled waveguide slot radiators
Heat shield efficiency over plane surface during injection through two tangential slots studied in wind tunnel
Dielectric cover effects on radiation properties of cross slots in rectangular antenna
Radiation pattern lobing structure elimination for recessed annular slot in coated metal cylinder
Dielectric cover effect on resonant frequency of slots in rectangular waveguide, using Stevenson free space theory and plane-wave reflection coefficient
Compensation method for longitudinal slot effects on propagation constant and characteristic impedance of rectangular waveguide used in standing wave meter
This report recounts some of the successful experiments conducted in England and Germany on slotted wings and ailerons. Wind tunnel test results are given and examples of aircraft constructed with these new wing components are described.
This report gives the results of a recent series of experiments performed on a wing designed for a cantilever monoplane. Both wings were trapezial in their ground plan, with their tips rounded elliptically. These wing sections combine all known devices for increasing the lift, namely, the slot, the increased camber and angle of attack by means of an aileron running the whole length of the span. The last advance included in the wing section was an increase in wing area by means of an auxiliary wing adjusted by a sort of rectangular joint.
The present report contains the results of a few experiments on three airfoils to which the rear portions, having chords respectively 1/4, 1/3, and 2/5 of the total chords, are hinged so as to form ailerons, especial attention being given to the shape of the slot between the aileron and the main portion of the aileron.
Pressure distribution measurements were made over an airfoil with slotted Frise aileron up to 0.76 Mach at various angles of attack and aileron defections. Section characteristics were determined from these pressure data. Results indicated loss of aileron rolling power for deflections ranging from -12 Degrees to -19 Degrees. High stick forces for non-differential deflections incurred at high speed, which were due to overbalancing tendency of up-moving aileron, may precipitate serious control difficulties. Detailed results are presented graphically.
Twin slot antennas coupled to superconducting devices are currently being developed for terahertz mixers and direct detectors for astronomical observations.
A 20 GHz active receive slot array has been developed for operation in the downlink frequency band of NASA's Advanced Communication Technology Satellite (ACTS) for the ACTS Mobile Terminal (AMT) project. The AMT is to demonstrate voice and data communication between a mobile terminal in Los Angeles, California, and a fixed terminal in Cleveland, Ohio, via the ACTS satellite.
An active receive slot array has been developed for operation in the downlink frequency band, 19.914-20.064 GHz, of NASA's Advanced Communication Technology Satellite (ACTS) for the ACTS Mobile Terminal (AMT) project.
In this paper, we present the design of a cognitive tapered slot circular array (TSCA) antenna with multiple electronically switched sector beams for lunar surface communication. The circular array is capable of sensing the frequency, power, and direction of arrival of the RF signals. The design of the TSCA builds on our prior work on the development of a single TSA element with a balanced microstrip/coax feed. The measured return loss of the single TSA element shows wide bandwidth with good impedance match across the 5 to 35 GHz frequency range. Additionally, the single TSA has good radiation patterns. The single TSA serves as the building block for a four-element TSCA with multiple electronically switched sector beams for sensing and communications.