Photodetection Technology Based on Laser Coding Emission

2011 ◽  
Vol 189-193 ◽  
pp. 3745-3749 ◽  
Author(s):  
Jing Guo ◽  
He Zhang ◽  
Xiang Jin Zhang ◽  
Xiao Feng Wang
Keyword(s):  
High Sensitivity ◽  
Avalanche Photodiode ◽  
High Gain ◽  
Low Noise ◽  
High Signal ◽  
Weak Signal ◽  
Echo Signal ◽  
Long Distance ◽  
The Poor ◽  
Theory And Experiment

For the extremely weak echo signal and the poor anti-interference ability of the long-distance laser fuze, the high signal noise ratio (SNR) receiving system based on laser coding mode was designed. In order to improve the weak signal receiving ability, the avalanche photodiode (APD) with high sensitivity, low noise and high gain was adopted. And the optimum multiplication factor of APD when the system obtains the highest SNR was analyzed and calculated. Then, the amplifying circuit optimum matching with APD and the decoding circuit were designed, and validated by the experiments. The theory and experiment results indicate that the design is efficiency and capable to the long distance laser fuze, the system can exactly decode the weak laser coding signals received and export the ignition signal.

Design of Amplifying Circuit for Receiving Weak Signal for Laser Fuze

2013 ◽  
Vol 300-301 ◽  
pp. 1012-1017
Author(s):  
Bing Ting Zha ◽  
He Zhang ◽  
Jun Hong Wang ◽  
Jing Guo
Keyword(s):  
Small Volume ◽  
Avalanche Photodiode ◽  
High Gain ◽  
Low Noise ◽  
Weak Signal ◽  
Echo Signal ◽  
Long Distance ◽  
Detection Range ◽  
Simulation And Experiment ◽  
Processing Circuit

The echo signal received by laser fuze was very weak when the detection range increased. In order to expand the operating range of fuze, the reception capacity of fuze for weak signal should be improved. According to the requirements of long-range laser fuze receiving system as small volume, low-power, low-noise, high-gain, the amplifying circuit of the receiving system was analyzed and designed. To improve the ability of laser fuze for detecting weak signal, the high-sensitive, low-noise, inner-gain avalanche photodiode (APD) was used as a photodetector in the system, and the low-noise preamplifier and voltage amplifying circuit was designed. The noise and frequency response of the amplifying circuit was researched and analyzed by simulation and experiment. The results show that the design is effective and feasible, which can meet the requirements of processing circuit as receiving weak signal from long-distance.

Design of Low-Noise Receiving Amplifier Circuit for Laser Proximity Fuze

2014 ◽  
Vol 926-930 ◽  
pp. 452-455
Author(s):  
Ya Yun Tan ◽  
He Zhang ◽  
Xiang Jing Zhang ◽  
Lin Gan
Keyword(s):  
Signal To Noise Ratio ◽  
High Sensitivity ◽  
Avalanche Photodiode ◽  
Low Noise ◽  
Noise Model ◽  
High Signal ◽  
Echo Signal ◽  
Detection Distance ◽  
Photoelectric Conversion ◽  
Noise Ratio

In order to improve the detection distance of laser proximity fuze without increasing laser power, the capability of laser fuze receiving weak laser echo signal must be improved. An avalanche photodiode (APD), which had the advantages of high sensitivity, low noise, with inner gain, was used as photodetector in laser fuze system to improve the capability of laser fuze detecting weak signal. The equivalent noise model of APD photoelectric conversion was analyzed, and the low-noise preamplifier and voltage amplification circuit matching the avalanche photodiode were designed. The noise ratio and frequency bandwidth of amplification circuit were analyzed and calculated, also the simulation and experimental verification were accomplished. The results showed that the circuit has wide bandwidth and high signal to noise ratio,which meets the requirements of subsequent processing circuitry of laser fuze.

scholarly journals A low-noise single-photon detector for long-distance free-space quantum communication

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Elena Anisimova ◽  
Dmitri Nikulov ◽  
Simeng Simone Hu ◽  
Mark Bourgon ◽  
Sebastian Philipp Neumann ◽  
...  
Keyword(s):  
Free Space ◽  
Quantum Communication ◽  
Detection Efficiency ◽  
Single Photon ◽  
Avalanche Photodiode ◽  
Low Noise ◽  
Photon Detector ◽  
Single Photon Detector ◽  
Long Distance ◽  
Communication Links

AbstractWe build and test a single-photon detector based on a Si avalanche photodiode Excelitas 30902SH thermoelectrically cooled to −100∘C. Our detector has dark count rate below 1 Hz, $500\ \mu\mathrm{m}$ 500 μ m diameter photosensitive area, photon detection efficiency around 50%, afterpulsing less than 0.35%, and timing jitter under 1 ns. These characteristics make it suitable for long-distance free-space quantum communication links, which we briefly discuss. We also report an improved method that we call long-time afterpulsing analysis, used to determine and visualise long trap lifetimes at different temperatures.

scholarly journals A Complete Two-Dimensional Avalanche Photodiode Based on MoTe2−WS2−MoTe2 Heterojunctions With Ultralow Dark Current

2021 ◽  
Vol 8 ◽  
Author(s):  
Tenghui Ouyang ◽  
Ximiao Wang ◽  
Shaojing Liu ◽  
Huanjun Chen ◽  
Shaozhi Deng
Keyword(s):  
Dark Current ◽  
Near Infrared ◽  
Transition Metal Dichalcogenides ◽  
High Sensitivity ◽  
Avalanche Photodiode ◽  
Infrared Region ◽  
Low Noise ◽  
Two Dimensional ◽  
Device Structure ◽  
Avalanche Gain

Two-dimensional (2D)-material-based photodetectors have recently received great attention due to their potentials in developing ultrathin and highly compact devices. Avalanche photodiodes (APDs) are widely used in a variety of fields such as optical communications and bioimaging due to their fast responses and high sensitivities. However, conventional APDs based on bulk materials are limited by their relatively high dark current. One solution to tackle this issue is by employing nanomaterials and nanostructures as the active layers for APDs. In this study, we proposed and fabricated an atomically-thick APD based on heterojunctions formed by 2D transition metal dichalcogenides (TMDs). A typical device structure was formed by stacking a semiconducting monolayer WS2 onto two metallic few-layer MoTe2 flakes. Due to the Schottky barrier formed between the TMD layers and their atomic thicknesses, the dark current of the APD is greatly reduced down to 93 pA. In addition, the APD can operate through a broad spectral range from visible to near-infrared region, with a responsivity of 6.02 A/W, an external quantum efficiency of 1,406%, and an avalanche gain of 587. We believe that the 2D APD demonstrated here provides a feasible approach for developing all-2D optoelectronic devices with simultaneous high-sensitivity and low noise.

Experimental Characterization of APD and Design of Quenching Circuit for Single-Photon Detection

2012 ◽  
Vol 246-247 ◽  
pp. 273-278 ◽  
Author(s):  
Hua Lü
Keyword(s):  
Integrated Circuit ◽  
Single Photon ◽  
Signal To Noise Ratio ◽  
Avalanche Photodiode ◽  
Low Noise ◽  
High Signal ◽  
Single Photon Detection ◽  
Single Photon Detector ◽  
Photon Detection ◽  
Geiger Mode

In this paper, we experimentally characterize the Inga As/Imp avalanche photodiode (APD), which is working in Geiger mode, so as to choose the single photon detector for quantum communication. Due to the fact that bias of APD tends to be flat after avalanche, we first adopt the methodology of passive quenching to determine dark breakdown voltage. Experiment results indicate that temperature reduction will widen the optimal operating region and increase the optimal multiplication; therefore APD will be more sensitive. Epitaxial APD is the best choice for single-photon detection among the APDs we have tested for its low noise level and high signal-to-noise ratio (SNR). Finally, we design a mixed passive-active quenching integrated circuit with gate control, which is quick with the quenching time of about 25ns and has controllable dead time with minimum of about 60ns.

The Transceiver Circuit Design of Digital Ultrasonic System

2013 ◽  
Vol 834-836 ◽  
pp. 968-973
Author(s):  
Xiao Feng Zhang ◽  
Fo Chang Xie ◽  
Guo Wei Yang ◽  
Wei Zhang
Keyword(s):  
Circuit Design ◽  
High Voltage ◽  
High Speed ◽  
Power Input ◽  
High Gain ◽  
Low Noise ◽  
Band Pass Filter ◽  
Echo Signal ◽  
Pass Filter ◽  
Input Use

This paper introduces the design process of the digital ultrasonic transmission circuit: echo receiving circuit and the echo signal regulate circuit. Among them, outside 500 V DC - DC module for high voltage power input, use non-tuned type circuit design ultrasonic transmission circuit ; Select high voltage fast recovery diode FR107 design echo receiving limiter circuit; Using ultra-high speed, low noise, low distortion of the integrated operational amplifier MAX4104ESA design preamplifier circuits and the band-pass filter circuits; Using linear decibels, low noise, wide bandwidth, high gain accuracy amplifier AD603 design echo amplifying circuit. The experimental results indicate that the basic realization of the ultrasonic transceiver circuit and echo signal conditioning functions.

scholarly journals Extending OTDR Distance Span by External Front-End Optical Preamplifier

Electronics ◽  
2021 ◽  
Vol 10 (18) ◽  
pp. 2275
Author(s):  
Adriana Lipovac ◽  
Vlatko Lipovac ◽  
Mirza Hamza ◽  
Vedran Batoš
Keyword(s):  
Dynamic Range ◽  
Noise Figure ◽  
Cost Effective ◽  
Optical Amplifier ◽  
High Gain ◽  
Low Noise ◽  
Long Distance ◽  
Optical Time Domain Reflectometer ◽  
Front End ◽  
Extension Model

Optical time-domain reflectometer (OTDR) is used to characterize fiber optic links by identifying and localizing various refractive and reflective events such as breaks, splices, and connectors, and measuring insertion/return loss and fiber length. Essentially, OTDR inserts a pulsed signal into the fiber, from which a small portion that is commonly referred to as Rayleigh backscatter, is continuously reflected back with appropriate delays of the reflections expressed as the power loss versus distance, by conveniently scaling the time axis. Specifically, for long-distance events visibility and measurement accuracy, the crucial OTDR attribute is dynamic range, which determines how far downstream the fiber can the strongest transmitted optical pulse reach. As many older-generation but still operable OTDR units have insufficient dynamic range to test the far-end of longer fibers, we propose a simple and cost-effective solution to reactivate such an OTDR by inserting a low-noise high-gain optical preamplifier in front of it to lower the noise figure and thereby the noise floor. Accordingly, we developed an appropriate dynamic range and distance span extension model which provided the exemplar prediction values of 30 dB and 75 km, respectively, for the fiber under test at 1550 nm. These values were found to closely match the dynamic range and distance span extensions obtained for the same values of the relevant parameters of interest by the preliminary practical OTDR measurements conducted with the front-end EDFA optical amplifier, relative to the measurements with the OTDR alone. This preliminary verifies that the proposed concept enables a significantly longer distance span than the OTDR alone. We believe that the preliminary results reported here could serve as a hint and a framework for a more comprehensive test strategy in terms of both test diversification and repeating rate, which can be implemented in a network operator environment or professional lab.

Sign in / Sign up

Export Citation Format

Share Document