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Affine Function
The Experts below are selected from a list of 25035 Experts worldwide ranked by ideXlab platform
John Lygeros – One of the best experts on this subject based on the ideXlab platform.
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every continuous piecewise Affine Function can be obtained by solving a parametric linear program
European Control Conference, 2013Co-Authors: Andreas B Hempel, Paul J Goulart, John LygerosAbstract:It is well-known that solutions to parametric linear or quadratic programs are continuous piecewise Affine Functions of the parameter. In this paper we prove the converse, i.e. that every continuous piecewise Affine Function can be identified with the solution to a parametric linear program. In particular, we provide a constructive proof that every piecewise Affine Function can be expressed as the linear mapping of the solution to a parametric linear program with at most twice as many variables as the dimension of the image of the piecewise Affine Function. Our method is illustrated via two small numerical examples.
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ECC – Every continuous piecewise Affine Function can be obtained by solving a parametric linear program
2013 European Control Conference (ECC), 2013Co-Authors: Andreas B Hempel, Paul J Goulart, John LygerosAbstract:It is well-known that solutions to parametric linear or quadratic programs are continuous piecewise Affine Functions of the parameter. In this paper we prove the converse, i.e. that every continuous piecewise Affine Function can be identified with the solution to a parametric linear program. In particular, we provide a constructive proof that every piecewise Affine Function can be expressed as the linear mapping of the solution to a parametric linear program with at most twice as many variables as the dimension of the image of the piecewise Affine Function. Our method is illustrated via two small numerical examples.
Anding Zhu – One of the best experts on this subject based on the ideXlab platform.
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Instantaneous Sample Indexed Magnitude-Selective Affine Function-Based Behavioral Model for Digital Predistortion of RF Power Amplifiers
IEEE Transactions on Microwave Theory and Techniques, 2018Co-Authors: Wenhui Cao, Anding ZhuAbstract:In this paper, we present a new behavioral model for digital predistortion (DPD) of RF power amplifiers in wireless transmitters. Derived from the decomposed vector rotation model, the new model uses magnitude-selective Affine Functions as nonlinear operators to construct nonlinear behavior of the model, leading to a highly efficient hardware implementation. Moreover, cross-terms are carefully redesigned based on a new formulation of model structure that not only improves the modeling performance but also significantly lowers the complexity of model extraction. Simulation and experimental results have demonstrated its superior performance and efficient hardware implementation, making this model well suitable for future DPD deployment in 5G small cell base stations where digital hardware resource is highly constrained.
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Magnitude-selective Affine Function based digital predistorter for RF power amplifiers in 5G small-cell transmitters
2017 IEEE MTT-S International Microwave Symposium (IMS), 2017Co-Authors: Wenhui Cao, Anding ZhuAbstract:To accommodate small-cell deployment in future 5G wireless communications, a magnitude-selective Affine Function based digital predistortion model for RF power amplifiers is proposed. This model has a very simple model structure and is easy to implement. Experimental results showed, by employing this model, substantial hardware resource reduction can be achieved without sacrificing performance in comparison with the existing models.
Samuel Verdú – One of the best experts on this subject based on the ideXlab platform.
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ICC – High-SNR power offset in multi-antenna Ricean channels
IEEE International Conference on Communications 2005. ICC 2005. 2005, 2005Co-Authors: Antonia Maria Tulino, A Lozano, Samuel VerdúAbstract:In the high-SNR regime, the multi-antenna mutual information behaves as an Affine Function of SNR|/sub dB/, described by the multiplexing gain, which quantifies the multiplicative increase as Function of the number of antennas, and the power offset (zero-order term in dB). The conventional high-SNR analysis that considers only the multiplexing gain is unable to assess the impact of channel features such as the Rician factor since, irrespective thereof, the multiplexing gain equals the minimum of the number of transmit and receive antennas. The impact of the Rician factor at high SNR can be conveniently quantified through the corresponding power offset, which this paper evaluates in closed-form.
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ISIT – High-SNR power offset in multiantenna communication
International Symposium onInformation Theory 2004. ISIT 2004. Proceedings., 2004Co-Authors: A Lozano, Antonia Maria Tulino, Samuel VerdúAbstract:In this paper, the high-SNR multiantenna capacity with coherent receivers on the multiplexing gain, i.e., the multiplicative increase as Function of the number of antennas is analyzed. For most channels of interest, such multiplexing gain equals the minimum of the number of transmit and receive antennas. This traditional characterization, however, is unable to quantify the impact of many relevant channel features. As a Function of SNR, the capacity is very well approximated, from moderate SNR on, as an Affine Function. The impact of the various channel features is captured in the power offset (in dB) or zero-order term in the Affine expansion.