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Range Sidelobe Suppression for Barker Codes
IEEE Transactions on Aerospace and Electronic Systems, 1971The utility of Barker-type phase-reversal codes is extended by the use of sidelobe suppression techniques that can be easily implemented in digital form. It is shown that sidelobe suppression techniques can be found where the tapped delay line used to reduce the sidelobes has only a few distinct tap weights, in which case the complexity of the digital ...
August Rihaczek, Roger Golden
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Reflector antennas with suppressed sidelobes
1988 IEEE AP-S. International Symposium, Antennas and Propagation, 2003The radiation characteristics of a class of two-dimensional reflector antennas is investigated. An array of radiators is used to control the aperture field distribution and hence the gain and the sidelobe levels of the far radiated fields. The method of moments is used to find the induced surface current distribution, the aperture field, and the far ...
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Horn antenna with suppressed sidelobe level
Microwave and Optical Technology Letters, 1991AbstractA method whereby the sidelobe level of the radiation pattern of a horn antenna can be reduced is proposed. The sidelobes are reduced by curving the edges in the aperture of the antenna. Radiation patterns of regular and modified horns were calculated with GTD and compared with measured results.
J. W. Odendaal, C. W. I. Pistorius
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Differential Lobing in Sidelobe Suppression Systems
IEEE Transactions on Aerospace and Electronic Systems, 1981The sidelobe suppression function in the secondary surveillance radar system is analyzed when separate main and control antenna are used. Their vertical lobing structures are not matched with each other, so a differential lobing pattern comes out whose maxima and minima are enveloped by smooth curves depending on vertical displacement of phase centers ...
G. Marchetti +2 more
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Optimal sidelobe suppression for biphase codes
NTC '91 - National Telesystems Conference Proceedings, 2002A technique is developed for the generation of filters for pulse compression sidelobe reduction in radar systems. This technique has two advantages over the standard Wiener filtering technique: it minimizes sidelobe energy over multiple input sequences, and it can shape the sidelobe energy through the application of a weighting function that indicates ...
J.M. Baden, M.N. Cohen
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Variable-radius focused optical vortex with suppressed sidelobes
Optics Letters, 2006We propose a design for a phase mask for generating an optical vortex with suppressed sidelobes in the focal plane where the radius of the intensity ring is variable. A radial modulation added to conventional phase mask exp(iltheta) projects the light diffracted from different annular zones into a single intensity ring in the focal plane.
J, Lin, X-C, Yuan, S H, Tao, R E, Burge
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Range sidelobe suppression by locally weighting filter
Electronics and Communications in Japan (Part I: Communications), 1996AbstractOne of the important technologies in the pulsed radar is the pulse compression by means of chirp signals. This technology simultaneously satisfies the contradicting requirements of increased search distance, or the increase of the average transmission power, and of range resolution.
Naoki Ehara, Iwao Sasase, Shinsaku Mori
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Sidelobe suppression for phased array aeroacoustic measurements
4th AIAA/CEAS Aeroacoustics Conference, 1998Phased array test techniques are becoming increasingly popular in aeroacoustics. This is due, in part, to the use of optimized array designs (e.g., spiral shapes) which can operate over usefully wide frequency ranges with acceptable resolution and sidelobe rejection characteristics with practical numbers of microphones.
Robert Dougherty, Robert Stoker
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Study on DPCA Sidelobe Clutter Suppression
Applied Mechanics and Materials, 2014Due to the non-smooth movement of the platform, the actual multi-channel SAR system is difficult to satisfy the DPCA condition and it is required to compensate the motion error. Previous studies are only interested in the main lobe clutter suppression performance inside the PRF, while ignoring the sidelobe clutter outside the PRF.
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New resonator filter with high sidelobe suppression
IEEE 1992 Ultrasonics Symposium Proceedings, 2003A new resonator filter for IF applications which is superior to conventional approaches is reported. The design places acoustically coupled resonator cascades between two weighted single-phase unidirectional transducers (SPUDTs). This allows narrow bandwidth and small chip size, high sidelobe suppression, moderate group delay ripple and low loss at the
G. Scholl +3 more
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