共查询到20条相似文献,搜索用时 46 毫秒
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基于半导体光放大器中交叉偏振调制效应的波长转换器 总被引:4,自引:2,他引:4
了改善基于半导体光放大器(SOA)中交叉偏振调制效应(CPM)的波长转换器的转换信号码型效应,对交叉偏振调制一半导体光放大器波长转换器的工作原理进行了分析;通过讨论交叉偏振调制一半导体光放大器波长转换脉冲的上升沿和下降沿的频率啁啾,结合滤波器的透过谱特性,提出了一种利用滤波器的波长正斜率边和波长负斜率边分别对正相转换信号和反相转换信号进行码型优化的方案,并进行了实验验证。在信号码率为10Gb/s的交叉偏振调制一半导体光放大器波长转换实验中,采用光带宽为0.3nm的JDS滤波器优化转换信号的波形,基本消除了转换信号中长“1”码和长“0”码的码型效应,并将正相转换信号和反相转换信号的功率代价分别改善了3dB以上。 相似文献
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We report on a new type of polarization insensitive frequency conversion technique using four-wave mixing (FWM) in a semiconductor optical amplifier (SOA). In this technique the input signal is spectrally duplicated by a Mach-Zehnder type phase modulator. Then, the resulting two waves generate the frequency converted output signal by FWM with use of an additional pump wave. The converted output wavelength is independent of the wavelength of the input signal. In addition to the frequency conversion, the chirp of the input signal is removed by the FWM process bit-error-rate (BER)-measurements after transmission of the converted signal over standard communication fiber are reported 相似文献
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Durhuus T. Joergensen C. Mikkelsen B. Pedersen R.J.S. Stubkjaer K.E. 《Photonics Technology Letters, IEEE》1994,6(1):53-55
Penalty free wavelength conversion is demonstrated at 2.5 Gbit/s over a wavelength span of 12 nm by the use of semiconductor optical amplifier (SOA)'s in a Mach-Zehnder configuration. An increase in the extinction ratio is measured for the converted signal compared to the input signal implying signal regeneration as well as wavelength conversion 相似文献
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实验研究了基于半导体光放大器(SOA)的四波混频(FWM)效应的单抽运光正交频分复用(OFDM)信号的波长变换系统.信号光源和抽运光源分别由两个不同输出波长的可调分布反馈式激光器(DFB-LD)产生.信号光源经2.5 Gb/s OFDM的电信号直接调制后再和抽运光源耦合,经光放大器后在SOA实现波长变换.实验结果显示,耦合信号经SOA四波混频效应后,产生新波长的信号光将携带OFDM信号,且转换效率与信号光和抽运光的功率、波长以及两者的偏振夹角有关.同时也测量了转换的OFDM信号的功率-误码曲线和接收星座图. 相似文献
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A new low-cost strain measurement system has been developed for the mechanical testing of biological soft tissues. The technique creates four spots of light on a tissue sample surface by piercing the tissue sample with two pairs of small light-conducting optical fibers (one pair for each axis of a biaxial stretch), terminated by high intensity infrared emitters. A large-area photodiode, located below the tissue sample, detects the light emitted from the two pairs of light-spots. Analog and digital circuitry analyze the current signal from the photodiode to determine the position of a light-spot in real time. Each infrared emitter is sequentially cycled "on" at a rate of 3 kHz and the resulting photodiode current signal, after being converted to a voltage signal, is held by an integrated circuit sample and hold amplifier. Analog differencing of pairs of light-spot voltage signals provides a final output proportional to the separation between coaxial light-spots. 相似文献
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Shibao Wu Xiaohan Sun Mingde Zhang 《Journal of Infrared, Millimeter and Terahertz Waves》2002,23(2):309-316
An analytical theory describing the frequency chirp characteristics of the wavelength converted signal in wavelength conversion based on cross-gain modulation (XGM) in semiconductor optical amplifier (SOA) is derived. By computation, we can see that low input pump power, high probe power, small line-width enhancement factor and low unsaturated single-pass gain of the SOA are favorable for reducing the frequency chirp of the wavelength converted signal. The analytical results have significance in understanding and designing wavelength converters. 相似文献
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An optical wavelength converter is proposed based on a laser cavity that has a laser-diode amplifier as an optically driven gain modulator and an Er-doped, slow-response gain medium. The device converts ASK signal wavelengths over ~8.7 nm. Though the converted NRZ data signal is inverted, it is amplified by 18 dB with its extinction ratios improved to nearly unity. Although the data rate converted in the experiment is no more than 0.5 Mb/s, high-gain planar-waveguide technology may reduce the cavity length and increase the data rate 相似文献
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An all-optical filter structure to simultaneously implement microwave bandpass and notch filter is proposed and experimentally demonstrated. The structure is based on a recirculating delay line (RDL) loop consisting of a semiconductor optical amplifier (SOA) followed by a tunable narrowband optical filter and a 10:90 coupler. The converted signal is generated in a wavelength conversion process based on cross-gain modulation of amplified spontaneous emission in the SOA. The converted signal circulating in RDL loop realizes a negative bandpass response. The negative bandpass filter and a broadband allpass filter are synthesized to achieve a notch filter with flat passband which can excise interference with minimal impact on the wanted signal. 相似文献
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We describe an all-optical wavelength conversion scheme for 1310 nm to 1550 nm based on nonlinear polarization rotation in a gain-transparent semiconductor optical amplifier(GT-SOA) which brings in the assistant light to improve the property of the converted light.From the SOA carrier density equations,the 1310 nm-to-1550 nm wavelength conversion scheme is analyzed by the Jones matrix.The phase shift between TE and TM modes and the converted light are simulated at bit rate of 30 Gbit/s.We also analyze the influence of the input signal power,the injected current and the assistant light power on the extinction ratio of the converted light. 相似文献
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The fabrication and performance of a InGaAsP-InP semiconductor optical amplifier for wavelength conversion in subcarrier multiplexed system is described. The amplifier is of the buried facet design and has polarization and reflectivity gain ripple of less than 1 dB. Using subcarrier multiplexing, multiple 50-Mb/s data streams at a wavelength of 1.553 /spl mu/m are infected into the amplifier. The gain nonlinearity of the amplifier transfers the data to a different wavelength of light simultaneously injected into the amplifier. Error free retrieval of subcarrier multiplexed data has been demonstrated for the wavelength converted output. The small signal bandwidth of the wavelength conversion process is 5 GHz. Calculation suggests that higher bandwidth is feasible at higher input powers at the expense of lower modulation transfer during wavelength conversion. 相似文献
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He Wen Huan Jiang Xiaoping Zheng Hanyi Zhang Yili Guo 《Photonics Technology Letters, IEEE》2007,19(18):1377-1379
In this letter, we propose two methods to enhance the performance of multichannel wavelength conversion of return-to-zero differential phase-shift-keying signal in a semiconductor optical amplifier (SOA) based on four-wave-mixing effect. The first one is optimizing the relative time delay of the multichannel signal to reduce the crosstalk-induced penalty in SOA. The second one is using the synchronous clock pumping to raise the power of converted signal. The experiment on wavelength conversion of two channels at 10-Gb/s signal showed the power penalty was improved more than 1 dB in the first method and about 1.5 dB in the second method. 相似文献
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机车轴承故障诊断中振动信号采集的研究 总被引:1,自引:0,他引:1
介绍了机车轴承故障诊断中振动信号采集的硬件实现.先通过压电式加速度传感器对振动信号进行拾取,然后经过电荷放大器、抗混滤波器等系列电路对拾取的微弱信号进行处理,最后进入A/D转换电路得到微机可以识别的数字信号,从而实现振动信号的采集. 相似文献
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针对语音接口常见的信号幅度动荡的问题,设计了基于语音编解码芯片AIC23和数字信号处理器TMS320VC5416的语音接口。研究了基于AIC23内部可变增益放大器的语音信号自动增益控制(AGC)方法,所设计的语音接口电路简单、音质清晰、音量稳定。 相似文献
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A. Harb Y. Hu M. Sawan A. Abdelkerim M.M. Elhilali 《Analog Integrated Circuits and Signal Processing》2004,39(1):39-54
In this paper, we describe a low-power low-voltage CMOS very low signal acquisition analog front-end of sensor electronic interfaces. These interfaces are mainly dedicated to biomedical implantable devices. In this work, we focus on the implantable bladder controller. Since the nerve signal has very low amplitude and low frequency, it is, at first fed to a low-voltage chopper amplifier to reduce the flicker (1/f) noise and then amplified with a programmable gain high CMRR instrumentation amplifier. This is followed by an analog signal processing circuit to rectify and bin-integrate (RBI) the amplified signal. The resulting RBI is then converted to digital and transferred to the implant's central processor where information about bladder can be extracted. The numerous analog modules of the system have been implemented in CMOS 0.35 μm, 3.3 V technology. The design, simulation and measurement results of the proposed interface are presented. At supply voltage of 2.2 V the power dissipation is less than 1.4 mW, the input equivalent noise is 56 nV/ $\sqrt {{\text{Hz}}} $ and the error in RBI calculation is less than 0.15%. 相似文献