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Sidelobe-Suppressed Bessel Beam Using Hologram
2022 Conference on Lasers and Electro-Optics Pacific Rim (CLEO-PR), 2022We present the generation of a sidelobe suppressed Bessel beam (SBB) using a holographic technique. The peak intensity of the sidelobes of the generated SBB is about 70% less compared to a standard Bessel beam.
Jerin Geogy George +2 more
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Sidelobe suppression in corrugated-waveguide filters
Optics Letters, 1977The reflection sidelobes of a corrugated optical waveguide filter are shown to be suppressed when the corrugation depth is tapered with a function that has low, Fourier-transform sidelobes. Several specific taper functions are considered, and sidelobe levels lower than −70 dB are shown to be feasible.
P S, Cross, H, Kogelnik
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ICAO Antenna for sidelobe suppression
2019 Conference on Microwave Techniques (COMITE), 2019The paper presents the Chu-Dunbar reflector antenna for primary surveillance radar 1.25-1.35 GHz and integrated monopulse system for secondary surveillance radar at frequency band 1.03 and 1.09 GHz. The main topic of this paper is the mechanical concept of a dipole antenna array that produces a monopulse antenna diagram at a horizontal (azimuthal ...
Vadim Zavodny +2 more
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Rugate filter sidelobe suppression using half-apodization
Applied Optics, 1993Rugate filters reflectance spectra were calculated for various index profiles with half-Gaussian modulation; graded-index as well as step-index profiles were used. The results show excellent sidelobe suppression around the stopbands, relatively high optical density, and good flatness in the reflectance band.
H A, Abu-Safia +2 more
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Ultrasonic horn with sidelobe suppressing centerpiece
The Journal of the Acoustical Society of America, 1988An ultrasonic horn assembly includes a horn with a bore tapering from a throat out to a mouth. An ultrasonic transducer is mounted in the throat of the horn. A beam narrowing insert includes a headpiece which tapers smoothly from a larger diameter base to a smaller diameter top.
James J. Phelan, Larry W. Ferguson
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Sidelobe suppression using adaptive filtering techniques
2001 CIE International Conference on Radar Proceedings (Cat No.01TH8559), 2002This paper presents an application of adaptive filtering in sidelobe suppression for radar pulse compression. Traditionally, windowing techniques are employed to reduce the sidelobe levels in the compressed waveform, at the expense of slightly reduced SNR and broadened main pulse width. The proposed adaptive filters use the ideal compressed waveform as
J.S. Fu, null Xin Wu
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Optimum Mismatched Filters for Sidelobe Suppression
IEEE Transactions on Aerospace and Electronic Systems, 1973This paper discusses the application of least-mean-squares approximate inverse filtering techniques to radar range sidelobe reduction. The method is illustrated by application to the 13-element Barker code. The performance of the least-mean-square inverse filter is compared with the matched filter and with the simplified sidelobereducing filters of ...
Martin Ackroyd, F. Ghani
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Mechanical Rotating Arrays for Sidelobe Suppression
2019 United States National Committee of URSI National Radio Science Meeting (USNC-URSI NRSM), 2019A novel approach by utilizing the fast mechanical rotation of arrays has been proposed for low sidelobe levels by integrating the rotational time-varying radiation pattern in a short time. From the experimental measured radiation pattern for a 4-element circular polarized array antenna with 0.87 element spacing, the mainlobe of the radiation pattern ...
Junming Diao +3 more
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