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Recently, Multiple-input Multiple-output and Orthogonal Frequency Division Multiplexing (MIMO-OFDM)-based technologies have been deployed in advanced wireless communication systems. In this paper, we present a prototype Field Programmable Gate Array (FPGA) design for an efficient physical layer implementation of a MIMO-OFDM technique. We propose a pipelined architecture using a Fast Fourier Transform that is shared across modulations for the MIMO-OFDM system. As more channels are used, more resources can be saved by using our proposed architecture. Experimental results show that the proposed implementation saves at least 40 percent of the hardware resources, while achieving the same data rate as known baseline MIMO-OFDM implementations. In addition, we propose efficient hardware implementation of the Almouti encoder and decoder. They are also designed to use minimum hardware resource by using the proposed architecture.  相似文献   
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In this study, we developed a method for the determination of PF‐04620110 (2‐{(1r,4r)‐4‐[4‐(4‐amino‐5‐oxo‐7,8‐dihydropyrimido[5,4‐f][1,4]oxazepin‐6(5H)‐yl)phenyl]cyclohexyl}acetic acid), a novel diacylglycerol acyltransferase 1 (DGAT‐1) inhibitor, in rat plasma and validated it using liquid chromatography–tandem mass spectrometry (LC‐MS/MS). Rat plasma samples were processed following a protein precipitation method by using acetonitrile and were then injected into an LC‐MS/MS system for quantification. PF‐04620110 and imipramine (internal standard) were separated using a Hypersil Gold C18 column, with a mixture of acetonitrile and 10 mm ammonium formate (90:10, v/v) as the mobile phase. The ion transitions monitored in positive‐ion mode [M + H]+ of multiple‐reaction monitoring were m/z 397.0 → 260.2 for PF‐04620110 and m/z 280.8 → 86.0 for imipramine. The detector response was specific and linear for PF‐04620110 at concentrations within the range 0.05–50 µg/mL and the signal‐to‐noise ratios for the samples were ≥10. The intra‐ and inter‐day precision and accuracy of the method matched the acceptance criteria for assay validation. PF‐04620110 was stable under various processing and/or handling conditions. PF‐04620110 concentrations in the rat plasma samples could be measured up to 24 h after intravenous or oral administration of PF‐04620110, suggesting that the assay is useful for pharmacokinetic studies in rats. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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An efficient and facile two-step strategy for the synthesis of (Z)-aurone from arylacetylenes and salicyladehydes, via silver(I) nitrate mediated cyclization/oxidation in the presence of potassium carbonate has been developed. The key feature of our method was delicate cascade reaction, to provide the corresponding (Z)-aurone in high yield and good regio- and stereo selectivity.  相似文献   
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Journal of Radioanalytical and Nuclear Chemistry - An in situ detector for radiological assessments of strontium-90 (90Sr) in river and lake water is developed, based on a CaF2(Eu) scintillator,...  相似文献   
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