Multiplex communications – Communication over free space – Combining or distributing information via frequency channels
Reexamination Certificate
2005-02-08
2005-02-08
Vu, Huy D. (Department: 2665)
Multiplex communications
Communication over free space
Combining or distributing information via frequency channels
C370S482000
Reexamination Certificate
active
06853632
ABSTRACT:
A gradient sensitivity based method is described for reducing Peak to Average Power Ratio in multicarrier communication systems. The method involves definition of a differentiable penalty function which has non-zero values whenever there is a peak violation. The gradient of the function with respect to the symbol magnitudes and phases is evaluated at the given symbol vector. Symbol perturbations are computed in the opposite direction of the gradient in such a way that the peaks are reduced and the amount of errors introduced in the symbols is not large enough to affect the decoding process. In order to reduce computation, a variant of the method is proposed where a peak reduction kernel is precomputed and stored. The kernel is rotated to the location of the peak and added with proper sign to reduce PAR.
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Arvind Mandayam T.
Verma Amit
Ryman Daniel J.
Vu Huy D.
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