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硅光电二极管的线性度及信噪比分析 总被引:6,自引:0,他引:6
通过分析光电检测时硅光电二极管线性响应及噪声特性,给出了硅光电二极管的线性度及信噪比公式,并结合噪声的电流 电压模型,对光电二极管用于光电检测时影响电路信噪比的因素进行了探讨。 相似文献
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关于合成孔径激光雷达中微弱光电信号的检测技术,分析了PIN光电二极管的主要噪声来源,设计了偏置电路和滤波电路;鉴于高频效应的影响,合理使用电磁屏蔽等措施。实验结果表明PIN电路的设计和电磁屏蔽的使用有效减小系统噪声,提高了信噪比,为合成孔径激光雷达的实际应用提供了依据。 相似文献
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基于PIN型光电转换电路的噪声研究 总被引:1,自引:0,他引:1
在微弱光信号探测系统中,由光电传感器输出的原始微弱电信号,首先进入的是光电转换电路,因此光电转换电路的信噪比将影响整个测试系统测量结果的准确性,这就非常有必要对电路的噪声进行研究。本文比较详细地分析了以PIN型光电二极管作为光电传感器的光电转换电路的各种噪声,并以此提出了一些有效减小光电转换电路噪声影响的方法。这些方法... 相似文献
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基于PSpice的光电探测电路仿真分析 总被引:2,自引:1,他引:1
光电探测电路的设计对光电探测系统的性能有重要的影响。采用PSpice电子电路设计软件,对光电探测电路性能进行了仿真。分析了光电二极管的PSpice模型,光电探测电路的时域特性、频域特性及噪声特性。通过PSpice软件的参数扫描功能,对电路参数进行了优化设计。利用PSpice软件的噪声分析功能,计算了系统等效噪声功率,并对后级电路设计参数进行了计算。 相似文献
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<正> 引言 光纤通信是通信史上又一次革命,其应用日益广泛。在短波长(0.8~0.9μm范围)光纤通信系统中,接收机通常采用硅雪崩光电二极管(APD)或硅PIN光电二极管。 D·R·Smith根据光电二极管和前置放大器参数,分析了PIN接收机和AFD接收机的噪声性能,指出把PIN光电二极管和一个输入电容低、漏电流小的FET前置放大器混合集成,可降低前置放大器的噪声,能显著改进PIN光电二极管接收机的灵敏 相似文献
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光电二极管后接结型场效应晶体管的光电探测电路,可提供低频散粒噪声限性能。采用现有的微波场效应晶体管,散粒噪声限性能的频带宽可扩展到兆赫范围。低噪声光电探测器用光电二极管可探测的最小信号功率通常受放大器噪声,而不是光电二极管噪声的限制。不过,在光电二极管后接一个场效应晶体管放大器,可大大改进信噪比。对于临界频率f_c以下的频率,可获得散粒噪声限性能,所以,光电二极管与场效应晶体管组合就成了光电参量上变频器、光电倍增管及低频雪崩光电二极管的劲敌。在下面的讨论中,假定光电二极管接到共源组态的场效应晶体管的栅极上。参照图1,信噪比很容易计算。此图中,反向偏置光电二极管由结电容C_d与串联电阻R_s表 相似文献
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一种低噪声的光电二极管阵列接口电路的设计 总被引:1,自引:0,他引:1
由于光电二极管阵列的暗电流以及后续处理电路的噪声对其信号输出有很大影响,所以设计了一种低噪声的光电二极管阵列接口电路.接口电路将感光二极管阵列和补偿二极管阵列输出的信号经过积分放大处理后再进行差动放大,降低瞬态干扰和暗电流噪声对输出信号的影响.对视频信号和无信号状态分别进行采样和保持,同时触发多次模数转换信号,以利于数据采集和降噪处理.测试结果表明,以上措施有效降低了光电二极管阵列输出信号的噪声. 相似文献
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A photon-counting receiver using an Si avalanche photodiode has been constructed. The circuit noise, dark-current noise and excess noise pulses can be discriminated perfectly from the signal pulse; thus a shot-noise-limited receiver sensitivity has been achieved. The dynamic range of the receiver is above 50 dB. 相似文献
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Optical Phase Locking by Local Oscillator Phase Dithering 总被引:1,自引:0,他引:1
A new type of optical phase-locked loop (OPLL), called the dither loop, is mathematically analyzed. The dither loop extracts a phase-error signal by applying a small phase disturbance to the local oscillator laser, and synchronously demodulating the resulting power fluctuation in the output signal of the receiver. The dither loop is superior to other OPLL designs, because it does not need the transmission of a residual carrier, it employs a 180deg/3-dB hybrid, an ac-coupled front end, and it accepts a large variety of input signals. Furthermore, in a dither loop, the amount of power which is fed to the phase-locking branch can be adaptively controlled within the receiver. The analysis first focuses on an expression for the phase detector gain in a dither loop. Using a linearized model, the phase-error variance due to phase dithering, white frequency noise induced phase noise and shot noise is evaluated. A simplified expression for the power penalty generated by the phase dither signal is presented. In a more complex calculation, the overall power penalty due to phase dithering and the residual phase error is found. This allows us to synthesize a design rule for dither loops with optimum performance measures. The design rule determines all relevant system parameters, based on specified values of the system bit rate, the laser linewidth, the photodiode responsivity and the required bit-error rate 相似文献
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为了解决红外光通信存在传输方向单一和消耗功率高问题,设计基于嵌入式技术的超低功耗红外光通信系统,系统单片机使用改进型STM32,将超低功耗红外发射装置嵌入到红外光通信系统中,该装置通过固定载波频率将输入音频信号,通过发送校准模式和音频传输模式调制为高频方波信号后,采用红外光管向外发射信号,并在电路中增加功率负载电流实现限流,降低红外光发射电路功耗。红外接收装置通过共射级放大电路接收信号,采用脉冲宽度调制(PWM)调制信号,实现信号高质量、低功率传输。红外通信模块实现红外发射装置和接收装置间信号的双向传输。系统采用保护驱动模式、中断模式与用户模式的红外通信协议栈,最大程度降低系统通信能耗,提高系统通信效率。实验结果表明:该系统能够实现信号和温度信号的有效传输,在休眠和正常运行时的功耗均较低,误码率低,是一种功率消耗低、通信质量高的红外光通信系统。 相似文献
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This paper describes the design of a low-noise optical receiver using Si bipolar transistors for high-speed optical transmission. The conventional common emitter-common collector circuit (CE-CC pair) and Darlingtou circuit (transimpedance amplifiers with parallel feedback) are studied. Optimal CE-CC pair collector-biasing current for attaining minimum noise current with a 400-MHz bandwidth is 2.7 mA, and less than 1.2 mA for the Darlington circuit. It is confirmed that the Darlington circuit is better than the CE-CC pair in signal-to-noise ratio by about 1.5 dB. The low-noise Darlington optical receiver with a Ge-avalanche photodiode has achieved an optical sensitivity of -41 dBm for a 400 Mbit/s RZ pulse with a bit error rate of 10-10. This is a 2.5-dB improvement in optical sensitivity over that of the conventional CE-CC receiver. 相似文献
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《Electron Devices, IEEE Transactions on》1985,32(12):2693-2698
This paper describes the design of a low-noise optical receiver using Si bipolar transistors for high-speed optical transmission. The conventional common emitter-common collector circuit (CE-CC pair) and Darlington circuit (transimpedance amplifiers with parallel feedback) are studied. Optimal CE-CC pair collector-biasing current for attaining minimum noise current with a 400-MHz bandwidth is 2.7 mA, and less than 1.2 mA for the Darlington circuit. It is confirmed that the Darlington circuit is better than the CE-CC pair in signal-to-noise ratio by about 1.5 dB. The low-noise Darlington optical receiver with a Ge-avalanche photodiode has achieved an optical sensitiyity of -41 dBm for a 400 Mbit/s RZ pulse with a bit error rate of 10-10. This is a 2.5-dB improvement in optical sensitivity over that of the conventional CE-CC receiver. 相似文献
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Watabe T. Goto M. Ohtake H. Maruyama H. Abe M. Tanioka K. Egami N. 《Electron Devices, IEEE Transactions on》2003,50(1):63-69
We propose a new signal readout method that uses a charge-transfer circuit. Its application is to an ultrahigh-sensitivity CMOS image sensor on which an avalanche-mode photoconductive film is overlaid. The charge-transfer circuit makes it possible to obtain high signal-to-noise ratio features by transferring signal charges accumulated in each photodiode to a parasitic capacitance that is small compared with the photodiode capacitance. A 138 /spl times/ 138 passive-pixel prototype sensor that had the charge-transfer circuit in each column was fabricated and tested. The prototype's column-to-column fixed-pattern noise and random noise were, respectively, 56.7 and 58.4 dB below the saturation signal level, which demonstrated its potential as a signal readout circuit for a next-generation ultrahigh-sensitivity CMOS image sensor. 相似文献
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Van Den Broeke L.A.D. De Jong L.P. Davidse J. Van Roermund A.H.M. 《Communications, IEEE Transactions on》1995,43(9):2493-2501
A novel low-cost multichannel optical transmission system for video signals is described. The system uses time-division multiplex pulse-position modulation (TDPPM). The transmitter and receiver are realized in a standard bipolar process while an external low-cost laser and PIN photodiode are used. A maximum of 16 channels can be multiplexed, while achieving a weighted signal-to-noise ratio (SNR) of 54 dB, a differential gain of 1% and a differential phase of 0.5°. For a launched power of 0 dBm (pulse amplitude), the optical budget for a 45 dB weighted SNR exceeds 20 dB. Besides video signals the system is also capable of handling other signals such as digital coded audio signals or computer data. The feasibility of a four-channel system has been confirmed by measurements 相似文献