共查询到20条相似文献,搜索用时 109 毫秒
1.
ecauseithastheadvantagesofhighsensitivity,anditiseasytodemodulateandconvenienttoselectinFDMsystem,thecoherentopticalfibercomm... 相似文献
2.
1 IntroductionOpticalfibersandintegratedopticalwaveguideshavebeenusedinmanyareassuchastelecommuni cations,sensortechnology ,spectroscopyandmedicine[1 ] .Asiswellknown ,thetotalreflectionwillhappenwhentheangleoftheincidentlightattheinterfaceoftwokindsofmate… 相似文献
3.
1 IntroductionThehigh speedandlong distance (non regen erative)transmissionisthemainpursuedgoalofop ticalfibercommunications.TheuseofErbium DopedFiberAmplifiers (EDFAs) [1~4] hasbeendemonstratedtobeaneffectivemethodforcompen satingfiberlossinhigh speedandlong d… 相似文献
4.
The Transmission Performance of Non-zero Dispersion Shifted Fiber Communication Systems Using In-line Phase-sensitive Amplifiers 总被引:1,自引:0,他引:1
1 IntroductionHigh speedlong distance (non regenerative)transmissionisthemaingoalofopticalfibercommu nications.Thefactorslimitingtransmissionspeedanddistancearefiberloss,Group velocityDisper sion (GVD )andfibernonlinearity .IthasbeenshownthatErbium dopedFiber… 相似文献
5.
《半导体光子学与技术》1997,(3)
AlOpticalWavelengthConversionfrom1.3μmto1.55μmUsingTwo-segmentDFBLasers①LUOBin,LUHongchang,CHENJianguo(SouthwestJiaotongUnive... 相似文献
6.
Highperformancesuperluminescentdiodesat1.3μmwavelengthZHUZhiwen;CAIHaiqing(ChongqingOptoelectronicsResearchInstitute,Yongchua... 相似文献
7.
8.
1.3μmwidebandwidthsemiconductorlasermoduleWAWGPinhong;CHIKaiqing(ChongqingOptoelectronicsResearchinstitute,Yongchuan632163,CH... 相似文献
9.
《半导体光子学与技术》1997,(3)
NovelMultimodeInterferenceOpticalFiltersinGeSi/Siforλ=1.3μmand1.55μm①②LIBaojun,LIGuozheng,LIUEnke(DepartmentofMicroelectronic... 相似文献
10.
1.3μmhigh-powersuperluminescentdiodeLIUMingda;SHIJiawei;MADongge;JINEnshun;LIShuwen(Dept.ofElec.Eng.,JilinUniversity,Changchu... 相似文献
11.
高功率密度自对准结构AlGaAs/GaAs异质结双极晶体管 总被引:6,自引:5,他引:1
利用各向异性的湿法刻蚀和侧墙隔离技术实现了发射极金属和基极金属的自对准 ,采用该自对准技术成功地研制出了自对准结构的 Al Ga As/ Ga As异质结双极晶体管 ,器件直流电流增益大于 2 0 ,电流增益截止频率 f T 大于30 GHz,最高振荡频率 fmax大于 5 0 GHz,连续波功率测量表明 :在 1d B增益压缩时 ,单指 HBT可以提供 10 0 m W输出功率 ,对应的功率密度为 6 .6 7W/ m m,功率饱和时最大输出功率 112 m W,对应功率密度为 7.48W/ m m,功率附加效率为 6 7% 相似文献
12.
Jae Yeob Shim Hyung‐Sup Yoon Dong Min Kang Ju Yeon Hong Kyung Ho Lee 《ETRI Journal》2005,27(6):685-690
DC and RF characteristics of 0.15 °m GaAs power metamorphic high electron mobility transistors (MHEMT) have been investigated. The 0.15 °m ° 100 °m MHEMT device shows a drain saturation current of 480 mA/mm, an extrinsic transconductance of 830 mS/mm, and a threshold voltage of ‐0.65 V. Uniformities of the threshold voltage and the maximum extrinsic transconductance across a 4‐inch wafer were 8.3% and 5.1%, respectively. The obtained cut‐off frequency and maximum frequency of oscillation are 141 GHz and 243 GHz, respectively. The 8 ° 50 °m MHEMT device shows 33.2% power‐added efficiency, an 18.1 dB power gain, and a 28.2 mW output power. A very low minimum noise figure of 0.79 dB and an associated gain of 10.56 dB at 26 GHz are obtained for the power MHEMT with an indium content of 53% in the InGaAs channel. This excellent noise characteristic is attributed to the drastic reduction of gate resistance by the T‐shaped gate with a wide head and improved device performance. This power MHEMT technology can be used toward 77 GHz band applications. 相似文献
13.
研制成功了可商业化的75mm单片超高真空化学气相淀积锗硅外延设备SGE500,并生长了器件级SiGe HBT材料.研制了具有优良小电流特性的多晶发射极双台面微波功率SiGe HBT器件,其性能为:β=60@VCE/IC=9V/300μA,β=100@5V/50mA,BVCBO=22V,ft/fmax=5.4GHz/7.7GHz@10指,3V/10mA.多晶发射极可进一步提供直流和射频性能的折衷,该工艺总共只有6步光刻,与CMOS工艺兼容且(因多晶发射极)无需发射极外延层的生长,这些优点使其适合于商业化生产.利用60指和120指的SiGe HBT制作了微波锗硅功率放大器.60指功放在900MHz和3.5V/0.2A偏置时在1dB压缩点给出P1dB/Gp/PAE=22dBm/11dB/26.1%.120指功放900MHz工作时给出了Pout/Gp/PAE=33.3dBm (2.1W)/10.3dB/33.9%@11V/0.52A. 相似文献
14.
A variable-gain low-noise amplifier (LNA) suitable for low-voltage and low-power operation is designed and implemented in a standard 0.18 /spl mu/m CMOS technology. With a current-reused topology, the common-source gain stages are stacked for minimum power dissipation while achieving high small-signal gain. The fully integrated 5.7 GHz LNA exhibits 16.4 dB gain, 3.5 dB noise figure and 8 dB gain tuning range with good input and output return losses. The LNA consumes 3.2 mW DC power from a supply voltage of 1 V. A gain/power quotient of 5.12 dB/mW is achieved in this work. 相似文献
15.
16.
A simple and cost-effective wavelength-switchable fiber ring laser based on a chirped moire fiber grating (CMFG)and an erbium-doped fiber amplifier (EDFA) is proposed,and stable wavelength Iasing oscillations at room temperature iS experimentally demonstrated.To serve as a wavelength selective element,the CMFG possesses excellent comb-like filtering characteristics including stable wavelength interval and ultra-narrow passband.and its fabrication method iS easy and flexible.The measured optical signal-to-noise ratio reaches the highest value of 50 dB and the power fluctuation of each channel output iS less than 0.5 dB within an hour.The output laser power of different channels is almost identical(difference of less than 1 dB) within the tunable range.Methods to optimize the laser performance are also discussed and the superiority of the CMFG iS experimentally demonstrated. 相似文献
17.
A highly linear MMIC power amplifier for wideband code-division multiple-access (W-CDMA) portable terminals has been devised and implemented with a new integrated on-chip lineariser. The proposed lineariser, consisting of an InGaP/GaAs heterojunction bipolar transistor (HBT) active bias circuit partially coupled to RF input power together with a feedback capacitor, effectively improves gain compression with little insertion power loss and no additional die area. The optimised lineariser improves maximum output power (P1 dB) by 2 dB and adjacent channel leakage power ratio (ACLR) by 4 dB, and the implemented HBT MMIC power amplifier exhibits a P1 dB of 30 dBm, a power gain of 30 dB, a power added efficiency of 42% at the maximum output power under an operation voltage of 3.4 V, and an ACLR of -34 dBc at 27 dBm of output power. 相似文献
18.
Taeksang Song Hyoung-Seok Oh Songcheol Hong Euisik Yoon 《Microwave and Wireless Components Letters, IEEE》2006,16(4):206-208
A 2.4-GHz fully integrated CMOS receiver front-end using current-reused folded-cascode circuit scheme is presented. A configuration utilizing vertically stacked low-noise amplifier (LNA) and a folded-cascode mixer is proposed to improve both conversion gain and noise figure suitable for sub-mW receiver circuits. The proposed front-end achieves a conversion gain of 31.5dB and a noise figure of 11.8dB at 10MHz with 500-/spl mu/A bias current from a 1.0-V power supply. The conversion gain and noise figure improvements of the proposed front-end over a conventional merged LNA and single-balanced mixer are 11dB and 7.2dB at 10MHz, respectively, with the same power consumption of 500/spl mu/W. 相似文献
19.
基于0.13μm SiGe HBT工艺,设计应用于无线局域网(WLAN)802.11b/g频段范围内的高增益射频功率放大器.该功放工作在AB类,由三级放大电路级联构成,并带有温度补偿和线性化的偏置电路.仿真结果显示:功率增益高达30dB,1dB压缩点输出功率为24dBm,电路的S参数S11在1.5~4GHz大的频率范围内均小于-17dB,S21大于30dB,输出匹配S22小于-10dB,S12小于-90dB.最高效率可达42.7%,1dB压缩点效率为37%. 相似文献
20.
《Microwave and Wireless Components Letters, IEEE》2009,19(12):828-830