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Chinese Optics Letters 2015年第12期13卷 12-17页

作者：刘翔杨爱英王雨冯立辉 School of Opto-electronics Beijing Institute of Technology National Science and Technology Venture Capital Development Center

A combination of light-emitting diode（LED） identification and a time-division multiplexing scheme is proposed in this Letter for indoor location-based service. With the scheme, the arrangement of white LED lamps and the structure of a data frame are designed to realize high-accuracy indoor positioning and location-based payload data transmission simultaneously. The results of the experiment demonstrate that the indoor positioning accuracy is 10 cm and 2 Mb/s data transmission with high signal quality is realized.

关键词： data communication systems data transfer Indoor positioning systems Location Location based services Multiplexing Telecommunication services Time division multiplexing

High-speed phosphorescent white LED visible light communications without utilizing a blue filter

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Chinese Optics Letters 2015年第8期13卷 27-31页

作者：李洪磊张旖旎陈雄斌吴春晖郭俊清高宗余陈弘达 State Key Laboratory of Integrated Optoelectronics Institute of SemiconductorsChinese Academy of Sciences School of Computer and communication Engineering University of Science and Technology Beijing

We experimentally demonstrate a high-speed phosphorescent white light emitting diode （LED） visible light communication （VLC） system without utilizing an optical blue filter. Here, the white light response is equalized by using the proposed analog equalizers. The 3 dB bandwidth of the VLC link could be extended from 3 to 132 MHz, which allows 330 Mbit/s non-return-to-zero on-off keying （NRZ-OOK） data transmission with a bit error ratio （BER） of 7,2 × 10^-10 and 672 Mbit/s 64-quadrature amplitude modulation （64-QAM） data transmission with a BER of 3.2 × 10^-3. These resultant BERs are less than the forward error correction （FEC） limit of 3.8× 10^-3. The VLC link distance is 1 m using a single 1 W LED. The transmitter and receiver modules are integrated to a compact size. Furthermore, the relationships between the signal performance and illumination level or optical power are investigated and analyzed.

关键词： Amplitude modulation data communication systems data transfer Detector circuits Error correction Light Light emission Optical communication Phosphorescence Visible light communication

200 Mb/s visible optical wireless transmission based on NRZ–OOK modulation of phosphorescent white LED and a pre-emphasis circuit

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Chinese Optics Letters 2014年第10期12卷 16-19页

作者：李洪磊陈雄斌郭俊清唐丹颖黄北举陈弘达 State Key Laboratory of Integrated Optoelectronics Institute of SemiconductorsChinese Academy of Sciences

We present a high-speed visible light communication （VLC） link that uses a commercially available phos- phorescent white light-emitting diode （LED）. Such devices have few megahertz bandwidth due to the slow response of phosphorescent component, which severely limit the transmission data rate of VLC system. We propose a simple pre-emphasis circuit. With blue-filtering and the pre-emphasis circuit, the bandwidth of VLC system can be enhanced from 3 to 77.6 MHz, which allows non-return-to-zero on-off-keying （NRZ- OOK） data transmission up to 200 Mb/s with the bit error ratio of 5.3 × 10-7 which is below 10-6. The VLC link operates at the room illumination level of -1000 lx at 1.1 m range using a single 1 W white LED.

关键词： Bandwidth data communication systems Detector circuits Light Light emission Light transmission Optical communication Phosphorescence Wave transmission

Optimal Partitioning and Granularity of Uniform Task Graphs

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Journal of Computer Science & Technology 1991年第2期6卷 185-194页

作者：章中云李国杰 Institute of Computing Technology Academia SinicaBeijing 100080

Task partitioning is an important technique in parallel processing.In this paper,we investigate the optimal partitioning strategies and granularities of tasks with communications based on several models of parallel computer systems.Different from the usual approach,we study the optimal partitioning strate- gies and granularities from the viewpoint of minimizing T as well as minimizing NT^2,where N is the number of processors used and T is the program execution time using N processors.Our results show that the optimal partitioning strategies for all cases discussed in this paper are the same——either to as- sign all tasks to one processor or to distribute them among the processors as equally as possible de- pending only on the functions of ratio of running time to communication time R/C.

关键词： Computer systems Programming Computers data communication systems Mathematical Techniques Graph Theory Optimization

communication Analysis and Granularity Assessment for a Transputer-Based System

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Journal of Computer Science & Technology 1990年第4期5卷 347-362页

作者：郭庆平 Y.Paker Wuhan University of Water Transportation Engineering The Polytechnic of Central London

This paper exposes the concurrent characteristic in the communication between processors in a transputer based system, and proposes an approximate formula for assessing the granularity of distributing the parallel processes among processors. The really measured results for a pipeline sorting program running on the T-rack confirm these deduced results.

关键词： Computer systems Programming Sorting Computer systems, Digital Parallel Processing Computers data communication systems

Synchro Controller of Radar on FPGA

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Wuhan University Journal of Natural Sciences 2003年第2A期8卷 409-413页

作者： Jiang Tie-zhen, Shi Zhen-hua, Wu Shi-caiSchool of Electronic Information, Wuhan University, Wuhan 430072,Hubei, China School of Electronic Information Wuhan University Wuhan Hubei China

This paper mainly represents the realization of synchro controller based on the programmable logic devices FPGA by request of HF ground wave radar synchro controller under the instance of making the best of the virtues of FPGA. This design introduces the data communication between PC and synchro controller by PC Bus, which can carry the synchronous signals parameters to RAM of synchro controller, then according to the theory that the result of comparing counter value with signals parameters is the needed wave, we produce all waves HF ground wave radar needs, moreover all waves are produced time-sharing in order to save resources.

关键词： data communication systems Field programmable gate arrays Programmable logic controllers Synchronization