Results 231 to 240 of about 956,208 (275)

APSK Constellation with Gray Mapping

IEEE Communications Letters, 2011
Amplitude phase shift keying (APSK) constellation is superior to its quadrature amplitude modulation (QAM) counterpart from the mutual information point of view. However, due to the lack of Gray mapping, it introduces high independent demapping loss. In this letter, a special kind of APSK constellations with Gray mapping (Gray-APSK) is proposed, which ...
Zaishuang Liu, Qiuliang Xie, Kewu Peng, Zhixing Yang   +3 more
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Gray matters! — Mapping the transition to psychosis

Schizophrenia Research, 2011
Despite many neuroimaging studies on schizophrenia showing brain abnormalities the exact time course of their occurrence is unknown. Studies of gray matter are a powerful tool in biological psychiatry and provide an unprecedented opportunity for brain structure investigations.
Borgwardt, Stefan, McGuire, Philip, Fusar-Poli, Paolo   +2 more
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Gray scale processing of hydrographic maps

Proceedings of 13th International Conference on Pattern Recognition, 1996
This paper investigates how gray scale information can be used in a hydrographic map understanding system to improve the system performance. To process gray scale scanned map images, we have implemented a topographic analysis method and a binary analysis method.
O.D. Trier, T. Taxt, A.K. Jain
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(Gray) Mappings for Bit-Interleaved Coded Modulation

2007 IEEE 65th Vehicular Technology Conference - VTC2007-Spring, 2007
Mappings for square quadrature amplitude modulation (QAM) are investigated in terms of the achievable capacity in bit-interleaved coded modulation (BICM). In G. Caire et al. (1998) it is conjectured that Gray labelings maximize this capacity. However, Gray mappings are not unique and it can be shown that the conjecture cannot hold in general for QAM ...
Clemens Stierstorfer, Robert F. H. Fischer   +1 more
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Improvements to APSK constellation with gray mapping

2014 IEEE International Symposium on Broadband Multimedia Systems and Broadcasting, 2014
Amplitude phase shift keying (APSK) constellation with gray mapping proposed in [2] provides considerable shaping gain compared with quadrature amplitude modulation (QAM). In this paper, some improvements to APSK Constellation with gray mapping are addressed.
Dazhi He, Yijun Shi, Yunfeng Guan, Yin Xu, Yao Wang, Wenjun Zhang, Honggang Yin   +6 more
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Accuracy of gray-scale coding in lung sound mapping

Computerized Medical Imaging and Graphics, 2010
Stethoscope evaluation of the lungs is widely accepted and practiced; however, there are some widely recognized, major limitations with its use. A safe device that helped solve these limitations by translating sound into objective, quantifiable images would have clinical utility.
Atul C, Mehta, Merav, Gat, Shlomit, Mann, J Mark, Madison   +3 more
openaire   +2 more sources

Histogram equalization algorithm for variable gray level mapping

2010 8th World Congress on Intelligent Control and Automation, 2010
The traditional histogram equalization algorithm is likely to cause information loss. The paper introduced a gray level mapping algorithm in which information entropy remains the same. The algorithm adjusting the gray scale transformation of the image, introduces a new transformation formula parameter β, and makes the spacing of two adjacent gray ...
null Youlian Zhu, null Cheng Huang
openaire   +1 more source