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Sidelobe suppression with orthogonal projection for OFDM systems
2012 Australian Communications Theory Workshop (AusCTW), 2012Sidelobe suppression, or out-of-band emission reduction, in OFDM systems can be achieved via time-domain windowing but this may result in significantly reduced spectrum efficiency. Alternatively, sidelobe cancellation and signal predistortion techniques have been proposed for spectrum shaping, but schemes achieving a good balance between complexity and
Antonio Cantoni +3 more
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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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Wireless Personal Communications, 2021
Cognitive radio (CR) is the cutting-edge technique to intercept the hindrance of spectrum paucity. This is done by allowing the spectrum to be utilized dynamically. Orthogonal frequency division multiplexing (OFDM), a best multi-carrier method, is a promising contender of CR.
Atif Elahi, Noor Gul, Shafqat Ullah Khan
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Cognitive radio (CR) is the cutting-edge technique to intercept the hindrance of spectrum paucity. This is done by allowing the spectrum to be utilized dynamically. Orthogonal frequency division multiplexing (OFDM), a best multi-carrier method, is a promising contender of CR.
Atif Elahi, Noor Gul, Shafqat Ullah Khan
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Suppression of quantization sidelobes of phased arrays
IEEE Antennas and Propagation Society Symposium, 2004., 2004Phase quantization errors appear in phased arrays utilizing the digital phase shifter for beam steering. And this cause relatively high parasitic sidelobes - quantization sidelobes. In consequence, the anti-interference ability of phased arrays decreases. The dependence of the array pattern on the rounding up probability is analyzed.
null Wenhui Shen, null Xilang Zhou
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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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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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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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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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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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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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