Browsing by Author "Chen, Yu-Hung"

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Full duplex 60-GHz RoF link employing tandem single sideband modulation scheme and high spectral efficiency modulation format
(2009-10-26)
Shih, Po-Tsung
;
Lin, Chun-Ting
;
Jiang, Wen-Jr
;
Chen, Yu-Hung
;
Chen, Jason (Jyehong)
This study proposes a full duplex 60-GHz band radio-over-fiber (RoF) link using a modified tandem single sideband (TSSB) modulation scheme with frequency doubling. Based on the modified TSSB modulation scheme, no dispersion induced fading is observed; high spectral efficiency vector signal can be utilized; and wavelength reuse can also be achieved. Both single carrier 8-QAM and QPSK-OFDM signals for down-link transmissions are experimentally demonstrated. After transmission of 50-km SSMF, no significant receiver power penalties are observed. Wavelength reuses with 1.25-Gb/s OOK using a reflective semiconductor optical amplifier (RSOA) for up-link transmission are also demonstrated. After transmission of 50-km SSMF, no significant receiver power penalties are also observed. (c) 2009 Optical Society of America
High Improvement in Conversion Efficiency of mu c-SiGe Thin-Film Solar Cells with Field-Enhancement Layers
(2012)
Yu, Shu-Hung
;
Lin, Wei
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Chen, Yu-Hung
;
Chang, Chun-Yen
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電子工程學系及電子研究所
The improved performance for hydrogenated microcrystalline silicon-germanium (mu c-Si1-xGex:H, x similar to 0.1) p-i-n single solar cells with hydrogenated microcrystalline silicon (mu c-Si:H) field-enhancement layers (FELs) is demonstrated for the first time. The fill factor (FF) and conversion efficiency (eta) increase by about 19% and 28% when the thickness of the mu c-Si FEL is increased from 0 to 200 nm, it is attributed to the longer hole life-time and enhanced electric field in the mu c-Si0.9Ge0.1:H layer. Therefore, we can successfully manufacture high-performance mu c-SiGe:H solar cells with the thickness of absorbers smaller than 1 mu m by conducting FELs. Moreover, the simulation tool is used to simulate the current-voltage (J-V) curve, thus we can investigate the carrier transport in the absorber of mu c-Si0.9Ge0.1:H solar cells with different EFLs.
Hybrid Access Network Integrated with Multi-level RF Vector Signal and Baseband Signal without Optical Filtering
(2009)
Shih, Po-Tsung
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Lin, Chun-Ting
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Chen, Yu-Hung
;
Jiang, Wen-Jr
;
Chen, Jason (Jyehong)
Hybrid access network integrated with multi-level wireless vector signal and wireline OOK signal without optical filter is proposed for the first time. 312.5-MSymbol/sec RF 8-PSK signal and 1.25-Gb/sec BB signal are experimentally demonstrated. (C) 2009 Optical Society of America
Hybrid Access Network Integrated With Wireless Multilevel Vector and Wired Baseband Signals Using Frequency Doubling and No Optical Filtering
(2009-07-01)
Shih, Po-Tsung
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Lin, Chun-Ting
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Jiang, Wen-Jr
;
Chen, Yu-Hung
;
Chen, Jason (Jyehong)
This letter experimentally demonstrated a hybrid access network which supports both radio-over-fiber and fiber-to-the-x systems. A 20-GHz radio-frequency (RF) 312.5-MSymbol/s M-ary phase-shift keying (PSK) signal and a baseband (BB) 1.25-Gb/s on-off keying signal are simultaneously generated and transmitted over an identical distributed infrastructure. The wired BB signal is compatible with the existing passive optical network (PON) system, and the wireless RF PSK signal can also share the same distributed infrastructure. The proposed system has no RF fading issue, no narrowband optical filter at remote node to separate the RF and BB signals, and can carry vector signals. Moreover, a frequency doubling for optical RF signal generation is achieved to reduce the bandwidth requirement of the transmitter. After transmission over 25-km standard signal-mode fiber, the receiver sensitivity penalties are less than 0.5 dB for both the RF and BB channels.
Hydroxynaphthyridine-Derived Group III Metal Chelates: Wide Band Gap and Deep Blue Analogues of Green Alq(3) (Tris(8-hydroxyquinolate)aluminum) and Their Versatile Applications for Organic Light-Emitting Diodes
(2009-01-21)
Liao, Szu-Hung
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Shiu, Jin-Ruei
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Liu, Shun-Wei
;
Yeh, Shi-Jay
;
Chen, Yu-Hung
A series of group III metal chelates have been synthesized and characterized for the versatile application of organic light-emitting diodes (OLEDs). These metal chelates are based on 4-hydroxy-1,5-naphthyridine derivates as chelating ligands, and they are the blue version analogues of well-known green fluorophore Alq(3) (tris(8-hydroxyquinolinato)aluminum). These chelating ligands and their metal chelates were easily prepared with an improved synthetic method, and they were facially purified by a sublimation process, which enables the materials to be readily available in bulk quantity and facilitates their usage in OLEDs. Unlike most currently known blue analogues of Alq(3) or other deep blue materials, metal chelates of 4-hydroxy-1,5-naphthyridine exhibit very deep blue fluorescence, wide band gap energy, high charge carrier mobility, and superior thermal stability. Using a vacuum-thermal-deposition process in the fabrication of OLEDs, we have successfully demonstrated that the application of these unusal hydroxynaphthyridine metal chelates can be very versatile and effective. First, we have solved or alleviated the problem of exciplex formation that took place between the hole-transporting layer and hydroxynaphthyridine metal chelates, of which OLED application has been prohibited to date. Second, these deep blue materials can play various roles in OILED application. They can be a highly efficient nondopant deep blue emitter: maximum external quantum efficiency (eta ext) of 4.2%; Commision Internationale de L'Eclairage x, y coordinates, CIE(x,y) = 0.15, 0.07. Compared with Alq(3), Bebqp(2) (beryllium bis(benzoquinolin-10-olate)), or TPBI (2,2',2 ''-(1,3,5-phenylene)tris(1-phenyl-1H-benzimidazole), they are a good electron-transporting material: low HOMO energy level of 6.4-6.5 eV and not so high LUMO energy level of 3.0 3.3 eV. They can be ambipolar and possess a high electron mobility of 10(-4) cm(2)/V s at an electric field of 6.4 x 10(5) V/cm. They are a qualified wide band gap host material for efficient blue perylene (CIE(x,y) = 0.14, 0.17 and maximum (eta ext) 3.8%) or deep blue 9,10-diphenylanthracene (CIE(x,y) = 0.15, 0.06 and maximum (eta ext) 2.8%). For solid state lighting application, they are desirable as a host material for yellow dopant (rubrene) in achieving high efficiency ((eta ext) 4.3% and (eta P) 8.7 lm/W at an electroluminance of 100 cd/m(2) or (eta ext) 3.9% and (eta P) 5.1 lm/W at an electroluminance of 1000 cd/m(2)) white electroluminescence (CIE(x,y) = 0.30, 0.35).
Simultaneous Generation and Transmission of 60-GHz RF and Baseband Signals Employing Only a Simple Single Electrode MZM
(2009)
Jiang, Wen-Jr
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Lin, Chun-Ting
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Chen, Yu-Hung
;
Shih, Po-Tsung
;
Hsu, Dar-Zu
Employing only a simple single electrode MZM, a novel hybrid access network, which is capable of generating and transmitting RF-vector (2.5-Gb/s QPSK at 60GHz) and baseband signals (1.25-Gb/s OOK) simultaneously, is proposed and experimentally demonstrated.
The aquatic animals' transcriptome resource for comparative functional analysis
(2018-05-09)
Chou, Chih-Hung
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Huang, Hsi-Yuan
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Huang, Wei-Chih
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Hsu, Sheng-Da
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Hsiao, Chung-Der
Background: Aquatic animals have great economic and ecological importance. Among them, non-model organisms have been studied regarding eco-toxicity, stress biology, and environmental adaptation. Due to recent advances in next-generation sequencing techniques, large amounts of RNA-seq data for aquatic animals are publicly available. However, currently there is no comprehensive resource exist for the analysis, unification, and integration of these datasets. This study utilizes computational approaches to build a new resource of transcriptomic maps for aquatic animals. This aquatic animal transcriptome map database dbATM provides de novo assembly of transcriptome, gene annotation and comparative analysis of more than twenty aquatic organisms without draft genome. Results: To improve the assembly quality, three computational tools (Trinity, Oases and SOAPdenovo-Trans) were employed to enhance individual transcriptome assembly, and CAP3 and CD-HIT-EST software were then used to merge these three assembled transcriptomes. In addition, functional annotation analysis provides valuable clues to gene characteristics, including full-length transcript coding regions, conserved domains, gene ontology and KEGG pathways. Furthermore, all aquatic animal genes are essential for comparative genomics tasks such as constructing homologous gene groups and blast databases and phylogenetic analysis. Conclusion: In conclusion, we establish a resource for non model organism aquatic animals, which is great economic and ecological importance and provide transcriptomic information including functional annotation and comparative transcriptome analysis.
Transcriptome sequencing based annotation and homologous evidence based scaffolding of Anguilla japonica draft genome
(2016-01-01)
Liu, Yu-Chen
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Hsu, Sheng-Da
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Chou, Chih-Hung
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Huang, Wei-Yun
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Chen, Yu-Hung
Background: Anguilla japonica (Japanese eel) is currently one of the most important research subjects in eastern Asia aquaculture. Enigmatic life cycle of the organism makes study of artificial reproduction extremely limited. Henceforth genomic and transcriptomic resources of eels are urgently needed to help solving the problems surrounding this organism across multiple fields. We hereby provide a reconstructed transcriptome from deep sequencing of juvenile (glass eels) whole body samples. The provided expressed sequence tags were used to annotate the currently available draft genome sequence. Homologous information derived from the annotation result was applied to improve the group of scaffolds into available linkage groups. Results: With the transcriptome sequence data combined with publicly available expressed sequence tags evidences, 18,121 genes were structurally and functionally annotated on the draft genome. Among them, 3,921 genes were located in the 19 linkage groups. 137 scaffolds covering 13 million bases were grouped into the linkage groups in additional to the original partial linkage groups, increasing the linkage group coverage from 13 to 14 %. Conclusions: This annotation provide information of the coding regions of the genes supported by transcriptome based evidence. The derived homologous evidences pave the way for phylogenetic analysis of important genetic traits and the improvement of the genome assembly.
Transmission of Wireless and Wired Services Employing a Simple System Architecture
(2010-04-15)
Jiang, Wen-Jr
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Lin, Chun-Ting
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Shih, Po-Tsung
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Chen, Yu-Hung
;
Chen, Jason (Jyehong)
This letter presents a novel modulation approach for simultaneous generation and transmission of optical radio-frequency (RF) wireless vector signal and baseband (BB) wireline signal using a single-electrode Mach-Zehnder modulator. Based on a double sideband with carrier suppression scheme and properly predistorted driving vector signal, a 2.5-Gb/ s quadrature phase-shift keying (QPSK) signal at 60 GHz is generated with a 1.25-Gb/ s BB ON-OFF-keying (OOK) signal. The proposed system can carry higher spectral efficiency vector signals and needs no optical filter to separate the BB and RF signals at remote nodes. Moreover, optical RF signal generation with frequency doubling is also achieved to reduce the bandwidth requirement of the transmitter. After transmission over 25-km single-mode fiber, the power penalties of the generated QPSK and OOK signals are about 4 and 0.1 dB, respectively.
WDM up-conversion employing frequency quadrupling in optical modulator
(2009-02-02)
Shih, Po-Tsung
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Lin, Chun-Ting
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Jiang, Wen-Jr
;
Chen, Jason (Jyehong)
;
Huang, Han-Sheng
This work presents an optical up-conversion system with frequency quadrupling for wavelength-division-multiplexing (WDM) communication systems using a dual-parallel Mach-Zehnder modulator without optical filtering. Four-channel 1.25-Gb/s wired fiber-to-the-x (FTTx) and wireless radio-over-fiber (RoF) signals are generated and transmitted simultaneously. Moreover, the decline in receiver sensitivities due to Mach-Zehnder modulator bias drifts is also investigated. Receiver power penalties of the 20-GHz up-converted WDM signals and baseband (BB) FTTx signals are less than 1 dB when bias deviation voltage is less the 20% of the half-wave voltage. After transmission over a 50-km SSMF, the receiver power penalties of both the BB and 20-GHz RF OOK signals are less than 1 dB. Notably, 60-GHz optical up-conversion can be achieved using 15-GHz radio frequency (RF) components and equipment. (C) 2009 Optical Society of America