Results 241 to 250 of about 340,877 (291)
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IEEE Transactions on Antennas and Propagation, 2019
The operating frequency of future communication systems will cover unlicensed millimeter-wave bands as well as existing microwave bands. Large frequency ratio antennas that can be applied to both frequency bands simultaneously and maintain the high isolation between the two channels are difficult to design. This paper presents a new design of dual-band
Jin Fan Zhang +3 more
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The operating frequency of future communication systems will cover unlicensed millimeter-wave bands as well as existing microwave bands. Large frequency ratio antennas that can be applied to both frequency bands simultaneously and maintain the high isolation between the two channels are difficult to design. This paper presents a new design of dual-band
Jin Fan Zhang +3 more
openaire +3 more sources
Apodization of annular apertures: Strehl ratio
Applied Optics, 1988We show that for any rotationally symmetric apodizer on the full aperture, there is a family of apodizers on the annular aperture with the same functional Strehl ratio vs defocus (W(20)) and vs spherical aberration (W(40)). However, in the latter case, the coefficients W(20) and W(40) are reduced by the factors (1 - epsilon(2)) and (1 - epsilon(2))(2 ...
J, Ojeda-Castaneda, E, Tepichin, A, Pons
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Aperture intensity ratio fiber-optic displacement sensor
Review of Scientific Instruments, 1987A displacement sensor based on the ratio of fiber-optic light emitted from two fixed position optical fibers into a third, movable fiber connected to a photodetector is described. Square-wave modulated light of opposite phases produces a corresponding square wave at the detector which has zero ac amplitude at the center position and an amplitude ...
Darold Wobschall, Shahram Hejazi
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Signal-to-noise ratio of Singer product apertures
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2017Abstract Formulae for the signal-to-noise ratio (SNR) of Singer product apertures are derived, allowing optimal Singer product apertures to be identified, and the CPU time required to decode them is quantified. This allows a systematic comparison to be made of the performance of Singer product apertures against both conventionally wrapped Singer ...
Paul M.E. Shutler, Kevin Byard
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Signal-to-noise ratio in coded aperture imaging
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2012Abstract We present a derivation of the signal-to-noise ratio (SNR) of a cyclic difference set (CDS) based coded mask which is simpler than that given in the literature, and which applies to any distribution of flux against the mask, not just Poisson statistics as is currently the case.
Paul M.E. Shutler +2 more
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Estimation oil-water mixture ratio using hybrid-polarized synthetic aperture radar
2021 IEEE International Geoscience and Remote Sensing Symposium IGARSS, 2021The oil-water mixture ratio for oil spills on the ocean surface is an important parameter for volume estimation of oil spills, response strategy for the oil spills, cleanup operations, and remediation planning for the impacts on wildlife. The hybrid-polarized (HP) mode compact polarization (CP) Synthetic Aperture Radar (SAR) is a new SAR mode. Such new
Haiyan Li, William Perrie, Jin Wu
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An affect of the aperture length to aperture width ratio on broadband shielding effectiveness
2011 XXXth URSI General Assembly and Scientific Symposium, 2011The influence of an aperture area (between 2λ2 and 11λ2) on the Shielding Effectiveness of metallic enclosures has been measured in an anechoic chamber, and wavelength dependent SE measurements are introduced. Measurement setup was established operating between 6GHz to 13GHz.
I. Bahadir Basyigit +3 more
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A Miniaturized Design of Shared-aperture Antenna with High Aperture Reuse Ratio for 5G Applications
2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring), 2019A novel 3.5/38 GHz dual-band shared-aperture antenna is proposed in this paper. Miniaturization technology of the patch antenna is introduced into the shared-aperture antenna for the first time to reduce the occupied area. Meanwhile, high aperture reuse ratio and high channel isolation are achieved to support the sub-6G and the millimeter-wave antennas
Chun Xu Bai, Yu Jian Cheng
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85‐2: 2117PPI VR LCD with ultra‐high aperture opening ratio
SID Symposium Digest of Technical Papers, 2023In this paper, the Pixel Design and the Process Technology of ultra‐high PPI display are investigated. For increasing the aperture open ratio in pixel design, the width of metal data line, the size of TFT and the crosstalk between metal lines are separately researched.
Tianmin Zhou +8 more
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A large-aperture high-extinction-ratio Faraday-rotator isolator
IEEE Journal of Quantum Electronics, 1973A 45° Faraday rotator has been built at the Naval Research Laboratory. This rotator is designed for use with a short-pulse high-peak-power laser, and it has demonstrated an extinction ratio in excess of 35 dB.
O. Barr, J. McMahon, J. Trenholme
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