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2013
To be considered ultra wideband (UWB) per FCC definition, a signal must satisfy one of the two frequency domain requirements as stated in Chap. 1. One family of signals that satisfy the UWB requirements are impulse radios. There are, however, a number of others. Impulse radios were treated in Chaps. 3 and 4.
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To be considered ultra wideband (UWB) per FCC definition, a signal must satisfy one of the two frequency domain requirements as stated in Chap. 1. One family of signals that satisfy the UWB requirements are impulse radios. There are, however, a number of others. Impulse radios were treated in Chaps. 3 and 4.
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Novel modulation scheme for VLC
Broadband Access Communication Technologies XII, 2018In this paper, we have proposed a novel modulation scheme for visible light communication (VLC), that has two preprocessing blocks namely, discrete Fourier transform (DFT) block and frequency domain signal shaping block, prior to conventional optical-orthogonal frequency division multiplexing (O-OFDM) modulation. Two variants of proposed scheme namely,
Hossam A. I. Selmy +2 more
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Coherent frequency∕phase modulation scheme
IEE Proceedings - Communications, 2002An L-phase-levelled coherent frequency/phase modulation (LCFPM) scheme is investigated. It is analysed for both spectral characteristics and bit error characteristics on the additive white Gaussian noise channel. Comparison with conventional joint frequency and phase modulations is conducted in terms of power and bandwidth efficiencies.
F.-C. Hung, C.-D. Chung, Y.-L. Chao
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Dual-modulation laser line-locking scheme
Applied Optics, 1991Dual modulation laser line locking, useful for long-term trace species monitoring, achieves wavelength stability
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Turbo Trellis Coded Modulation Schemes
2000The effectiveness of trellis coded modulation (TCM) techniques, proposed by Ungerboeck in 1982 [1], for communication over bandwidth limited channels is well established. TCM schemes have been applied to telephone, satellite and microwave digital radio channels, where coding gains of the order of 3-6dB are obtained with no loss of bandwidth or data ...
Branka Vucetic, Jinhong Yuan
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Introduction to digital modulation schemes
IEE Colloquium on Design of Digital Cellular Handsets, 1998The choice of digital modulation scheme will significantly affect the characteristics, performance and resulting physical realisation of a communication system. There is no universal 'best' choice of scheme, but depending on the physical characteristics of the channel, required levels of performance and target hardware trade-offs, some will prove a ...
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Modulation schemes of phase gratings
Optical Engineering, 1992Various methods developed to design phase gratings with specified diffraction patterns are systematized. In addition to differences with respect to the numerical technique applied, they differ in their structure modulation schemes. They are described and some of their characteristics, e.g., feature size in their structures, are compared.
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