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Obscure Spread Spectrum watermarking
2011 IEEE International Conference on Multimedia and Expo, 2011This paper investigates previous blind SS schemes which do not employ the host objects in the detection process, especially the Improved Spread Spectrum (ISS) scheme. It shows that these schemes result in a high false positive probability even in the absence of any attack.
Yongdong Wu, Szeling Yeo
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Spread-Spectrum Watermarking Security
IEEE Transactions on Information Forensics and Security, 2009This paper presents both theoretical and practical analyses of the security offered by watermarking and data hiding methods based on spread spectrum. In this context, security is understood as the difficulty of estimating the secret parameters of the embedding function based on the observation of watermarked signals.
Luis Pérez-Freire +1 more
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Performance analysis of spread spectrum protocols with adaptive spreading
IEEE Transactions on Wireless Communications, 2010Temporal fading is an inherent characteristic of wireless channels. Furthermore, in a multiuser spread spectrum network, the instantaneous value of the multiple access interference varies with time. As a consequence, the instantaneous signal-to-interference-plus-noise ratio varies from one frame to another.
Onyemelem Jegbefume +2 more
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Performance Criteria for Spread Spectrum Communications
IEEE Transactions on Communications, 1977The criteria for antijam (AJ) and anti-intercept (AI) systems are described, in terms of the appropriate action taken by the jammer or interceptor. Avoiding pseudonoise (PN) sequences which can be partially or totally predicted is a foremost criteria, especially for AJ, and use of nonlinear feedforward logic (NFFL) with long-period linear maximal ...
Marlin P. Ristenbatt, James L. Daws Jr.
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A spread spectrum network analyser
ISSPA '99. Proceedings of the Fifth International Symposium on Signal Processing and its Applications (IEEE Cat. No.99EX359), 2003The paper describes the realisation of a spread spectrum network analyser using appropriate software to control a PC interface card, like a soundcard. The software generates a digitised time waveform consisting of a spread spectrum signal containing a number of equal amplitude spectral components.
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Notes on Spread-Spectrum History
IEEE Transactions on Communications, 1983This paper presents additional historical information relating to the spread-spectrum history described in [1]. Included here are ties with speech scrambling technology, wide-band matched filter design, stimulus of the WHYN system design by British research, ITT's efforts to protect vital information during World War II, and other miscellaneous notes ...
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Spread spectrum multi-h modulation
IEEE Military Communications Conference, 'Bridging the Gap. Interoperability, Survivability, Security', 1990Applying direct random spreading to a digital information sequence prior to multi-h modulation creates a novel class of signals, called spread-spectrum multi-h (SSMH) signaling. The spectral efficiency allows control of the power spectral density, while the power-efficient modulation allows transmission at lower signal-to-noise ratios when the receiver
William D. Lane, Aubrey M. Bush
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Quantum Spread Spectrum Communication
Conference on Lasers and Electro-Optics 2010, 2010We demonstrate that spectral teleportation can coherently dilate the spectral probability amplitude of a single photon. In preserving the encoded quantum information, this variant of teleportation subsequently enables a form of quantum spread spectrum communication.
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Spread‐spectrum magnetic resonance imaging
Magnetic Resonance in Medicine, 2019PurposeA novel method for the acceleration of MRI acquisition is proposed that relies on the local modulation of magnetic fields. These local modulations provide additional spatial information for image reconstruction that is used to accelerate image acquisition.MethodsIn experiments and simulations, eight local coils connected to current amplifiers ...
Klaus Scheffler +5 more
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Spread spectrum communications: myths and realities
IEEE Communications Magazine, 1979Spread spectrum communication techniques date back to the early fifties. Since the earliest applications, system improvements have been more evolutionary than revolutionary. Like most improvements in electronic systems, these are due primarily to the availability of ever higher speed integrated circuit components, which translate in this case ...
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