Results 31 to 40 of about 978,152 (207)
Discrete Hartley matrix transform precoding-based OFDM system to reduce the high PAPR
ICT Express, 2019 The high peak-to-average power ratio (PAPR) is one of the major drawbacks of the orthogonal frequency division multiplexing (OFDM) systems that make non-linear distortion in practical implementation of high power amplifier (HPA).
Abbas Ali Sharifi
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Two-Stage and Walsh Interleavers for Interleave Division Multiple Access Systems [PDF]
Engineering and Technology Journal, 2014 Interleavers are essential system components for interleave division multiple access (IDMA). In this paper, two-stage interleavers are proposed based on two optimization criteria combines minimum spreading distance with regular permutation and ...
Muayad Sadik Croock
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Characterizing and Enumerating Walsh-Hadamard Transform Algorithms
CoRR, 2017 We propose a way of characterizing the algorithms computing a Walsh-Hadamard transform that consist of a sequence of arrays of butterflies ($I_{2^{n-1}}\otimes \text{DFT}_2$) interleaved by linear permutations. Linear permutations are those that map linearly the binary representation of its element indices.
François Serre, Markus Püschel
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Analytical Science Advances, 2022 The compressed sensing (CS) theory requires the signal to be sparse under some transform. For most signals (e.g., speech and photos), the non‐adaptive transform bases, such as discrete cosine transform (DCT), discrete Fourier transform (DFT), and Walsh ...
Yinsheng Zhang +3 more
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A Novel Autofocus Measure Based on Weighted Walsh-Hadamard Transform
IEEE Access, 2019 The autofocus measure plays an important role in passive digital imaging systems. However, most of the existing methods are more sensitive to the noise. In order to overcome this drawback, we proposed a novel autofocus measure based on the weighted Walsh-
Liqiang Guo, Xiang Cao, Lian Liu
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Computationally Efficient Robust Color Image Watermarking Using Fast Walsh Hadamard Transform
Journal of Imaging, 2017 Watermark is the copy deterrence mechanism used in the multimedia signal that is to be protected from hacking and piracy such a way that it can later be extracted from the watermarked signal by the decoder.
Suja Kalarikkal Pullayikodi +3 more
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The Karhunen-Loeve, Discrete Cosine, and Related Transforms Obtained via the Hadamard Transform
, 1978 International Telemetering Conference Proceedings / November 14-16, 1978 / Hyatt House Hotel, Los Angeles, CaliforniaThe Karhunen-Loeve transform for stationary data, the discrete cosine transform, the Walsh-Hadamard transform, and most other commonly ...
Knauer, S. C., Jones, H. W., Hein, D. N.
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Efficient quantum amplitude encoding of polynomial functions [PDF]
QuantumLoading functions into quantum computers represents an essential step in several quantum algorithms, such as quantum partial differential equation solvers.
Javier Gonzalez-Conde +3 more
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PAPR reduction of optical OFDM signals in visible light communications
ICT Express, 2019 Orthogonal frequency division multiplexing (OFDM) is extensively used in optical communications to achieve high rate transmission. In this paper, Vandermonde like matrix (VLM) pre-coding approach is offered to reduce the high peak-to-average power ratio (
Abbas Ali Sharifi
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A Walsh-Based Arbitrary Waveform Generator for 5G Applications in 28nm FD-SOI CMOS Technology
IEEE Access, 2023 This paper presents the first Arbitrary Waveform Generator (AWG) based on Walsh’s theory for wideband radio frequency (RF) conversion. The architecture is dedicated to 5G-FR1 applications (sub-6GHz) to perform a direct and large bandwidth ...
Pierre Ferrer +3 more
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