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IEEE Transactions on Communications, 1974
This paper deals with the requirements for the design of digital companding techniques in either delta or pulse-code modulation. Both delta and pulse-code modulation convert analogue signals into binary signals and in both these systems the dynamic range is normally small. By the use of companding, the dynamic range can be extended.
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This paper deals with the requirements for the design of digital companding techniques in either delta or pulse-code modulation. Both delta and pulse-code modulation convert analogue signals into binary signals and in both these systems the dynamic range is normally small. By the use of companding, the dynamic range can be extended.
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Exponential Companding Technique for PAPR Reduction in OFDM Systems
IEEE Transactions on Broadcasting, 2005In this paper, a new nonlinear companding technique, called "exponential companding", is proposed to reduce the high Peak-to-Average Power Ratio (PAPR) of Orthogonal Frequency Division Multiplexing (OFDM) signals. Unlike the /spl mu/-law companding scheme, which enlarges only small signals so that increases the average power, the schemes based on ...
T. Jiang, Y. Yang, Y.-H. Song
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Analysis of Companding Techniques Applied to Onboard Telemetry Systems
Applied Mechanics and Materials, 2012In order to increase the dynamic range and the signal-to-quantization noise ratio (SQNR) of telecommunication systems, companding techniques were developed, such as the μ-law and the A-law. These techniques allow a non-uniform quantization of the signal using a compressor circuit followed by a uniform quantizer in the transmitter and the reconstruction
Marcio Barbosa Lucks +1 more
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Two "noninvasive" techniques for syllabic companding in signal processors
IEEE Transactions on Circuits and Systems II: Analog and Digital Signal Processing, 2001Two novel methods are described for syllabic companding in signal processors. These methods make state variable updating unnecessary, for piecewise constant input and output gains. Measurements and simulations are used as confirmation of the validity of the proposed techniques.
L. Toth, G. Palaskas, Y.P. Tsividis
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Reversible watermarking method based on adaptive thresholding and companding technique
International Journal of Computer Mathematics, 2011Embedding and extraction of secret information as well as the restoration of the original un-watermarked image are highly desirable in sensitive applications such as military, medical, and law enforcement imaging. This paper presents a novel reversible watermarking approach for digital images using integer-to-integer wavelet transform, companding ...
Nisar Ahmed Memon +3 more
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PAPR reduction using precoding and companding techniques for OFDM systems
2015 International Conference on Advances in Computer Engineering and Applications, 2015For multipath propagation systems OFDM provides good choice but also suffers with high peak to average power ratio (PAPR) at the transmitter side. High PAPR values results in non-linearites at transmission leading to complex designing. Therefore reduction of PAPR is necessary for lesser complexities, higher efficiency and greater stability.
Deergha Agarwal +3 more
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A companding technique for PAPR reduction in DWT OFDM systems
2014 IEEE International Conference on Advanced Communications, Control and Computing Technologies, 2014Orthogonal frequency division multiplexing (OFDM) technique is considered as a advance technology in realizing high-speed wireless digital communications. However, high peak-to-average power ratio (PAPR) of transmitted signals is a major drawback for multi-carrier modulation systems such as orthogonal frequency division multiplexing and discrete ...
Bhawana Mohanty, Srinivas Ramavath
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Nonlinear companding transform technique for reducing PAPR of ODFM signals
IEEE Transactions on Consumer Electronics, 2012In this paper a novel nonlinear companding transform (NCT) scheme based on the inverse hyperbolic sine function is proposed for reducing the peak-to-average power ratio (PAPR) of orthogonal frequency division multiplexing (OFDM) signals. By introducing the variable companding parameters and an inflexion point in the companding function, it enables more
Y. Wang, L.-h. Wang, J.-h. Ge, B. Ai
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Generalized Trapezoidal Companding Technique for PAPR Reduction in OFDM Systems
Journal of Optical Communications, 2018AbstractThe main drawback in the performance of the Orthogonal Frequency Division Multiplexing (OFDM) system is the higher Peak-to-Average Power Ratio (PAPR) of the OFDM signals at the transmitter side. Companding is a well-known technique useful for reducing PAPR in the OFDM signal. This paper proposes a new nonlinear companding scheme that transforms
Saruti Gupta, Ashish Goel
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Integer DCT-based reversible watermarking for images using companding technique
SPIE Proceedings, 2004We present a high capacity reversible watermarking scheme using companding technique over integer DCT coefficients of image blocks. This scheme takes advantage of integer DCT coefficients' Laplacian-shape-like distribution, which permits low distortion between the watermarked image and the original one caused by the bit-shift operations of the ...
Bian Yang +4 more
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