Download or read book Characterization of advanced avalanche photodiodes for water vapor lidar receivers written by and published by DIANE Publishing. This book was released on with total page 62 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Characterization of Advanced Avalanche Photodiodes for Water Vapor Lidar Receivers written by Tamer F. Refaat and published by DIANE Publishing. This book was released on 2000 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Characterization of Advanced Avalanche Photodiodes for Water Vapor Lidar Receivers written by Tamer F. Refaat and published by . This book was released on 2000 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research was done to choose a suitable APD detector for the development of an advanced atmospheric water vapor differential absorption lidar detection system operating either at 720, 820, or 940 nm. The results point out the benefits of using the super low ionization ratio (SLIK) structure APD for its lower noise-equivalent power, which was found to be on the order of 2 to 4 fW/Hz 1/2, with an appropriate optical system and electronics. The water vapor detection systems signal-to-noise ratio will increase by a factor of 10.

Download or read book Characterization of Advanced Avalanche Photodiodes for Water Vapor Lidar Receivers written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-09-19 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: Development of advanced differential absorption lidar (DIAL) receivers is very important to increase the accuracy of atmospheric water vapor measurements. A major component of such receivers is the optical detector. In the near-infrared wavelength range avalanche photodiodes (APD's) are the best choice for higher signal-to-noise ratio, where there are many water vapor absorption lines. In this study, characterization experiments were performed to evaluate a group of silicon-based APD's. The APD's have different structures representative of different manufacturers. The experiments include setups to calibrate these devices, as well as characterization of the effects of voltage bias and temperature on the responsivity, surface scans, noise measurements, and frequency response measurements. For each experiment, the setup, procedure, data analysis, and results are given and discussed. This research was done to choose a suitable APD detector for the development of an advanced atmospheric water vapor differential absorption lidar detection system operating either at 720, 820, or 940 nm. The results point out the benefits of using the super low ionization ratio (SLIK) structure APD for its lower noise-equivalent power, which was found to be on the order of 2 to 4 fW/Hz(sup (1/2)), with an appropriate optical system and electronics. The water vapor detection systems signal-to-noise ratio will increase by a factor of 10.Refaat, Tamer F. and Halama, Gary E. and DeYoung, Russell J.Langley Research CenterDIFFERENTIAL ABSORPTION LIDAR; ATMOSPHERIC MOISTURE; AVALANCHE DIODES; MOISTURE METERS; PHOTODIODES; RADAR RECEIVERS; WATER VAPOR; CHARACTERIZATION; RADAR MEASUREMENT; FREQUENCY RESPONSE; IONIZATION; NOISE REDUCTION; SIGNAL TO NOISE RATIOS; ELECTRIC POTENTIAL; NOISE MEASUREMENT

Download or read book Characterization of Advanced Avalanche Photodiodes for Water Vapor Lidar Receivers Nasa written by United States. National Aeronautics and Space Administration and published by . This book was released on 2003* with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Frontiers In Electronics Future Chips Proceedings Of The 2002 Workshop On Frontiers In Electronics Wofe 02 written by Yoon Soo Park and published by World Scientific. This book was released on 2003-01-29 with total page 413 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 2002 Workshop on Frontiers in Electronics was the third in the series of WOFE workshops. Over 70 leading experts from academia, industry, and government agencies reported on the most recent developments in their fields and exchanged views on future trends and directions of the electronics and photonics industry. The issues they addressed ranged from system-on-chip to DNA doping, from ultrathin SOI to electrotextiles, from photonics integration on the ULSI platform to wide band gap semiconductor devices and solid state lighting. The rapid pace of electronic technology evolution compels a merger of different technical areas, and WOFE-02 provided a unique opportunity for cross-fertilization of the emerging fields of microelectronics, photonics, and nanoelectronics. The workshop was informal and stimulated provocative views, visionary outlooks, and discussions on controversial issues.

Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 2003 with total page 636 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Atmospheric Water Vapor DIAL Detection System written by Tamer F. Refaat and published by . This book was released on 2000 with total page 158 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis describes the design and validation of this new water vapor DIAL detection system which was integrated onto a small Printed Circuit Board (PCB) with minimal weight and power consumption. Comparing its measurements to an existing DIAL system for aerosol and water vapor profiling validated the detection system.

Download or read book Design of Advanced Atmospheric Water Vapor Differential Absorption Lidar Dial Detection System written by National Aeronautics and Space Adm Nasa and published by Independently Published. This book was released on 2018-09-19 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: The measurement of atmospheric water vapor is very important for understanding the Earth's climate and water cycle. The lidar atmospheric sensing experiment (LASE) is an instrument designed and operated by the Langley Research Center for high precision water vapor measurements. The design details of a new water vapor lidar detection system that improves the measurement sensitivity of the LASE instrument by a factor of 10 are discussed. The new system consists of an advanced, very low noise, avalanche photodiode (APD) and a state-of-the-art signal processing circuit. The new low-power system is also compact and lightweight so that it would be suitable for space flight and unpiloted atmospheric vehicles (UAV) applications. The whole system is contained on one small printed circuit board (9 x 15 sq cm). The detection system is mounted at the focal plane of a lidar receiver telescope, and the digital output is read by a personal computer with a digital data acquisition card.Refaat, Tamer F. and Luck, William S., Jr. and DeYoung, Russell J.Langley Research CenterATMOSPHERIC MOISTURE; WATER VAPOR; DESIGN ANALYSIS; DIFFERENTIAL ABSORPTION LIDAR; DETECTION; AVALANCHES; SENSITIVITY; LOW NOISE; PHOTODIODES; SIGNAL PROCESSING; PRINTED CIRCUITS; LOW WEIGHT; SIGNAL TO NOISE RATIOS; ATMOSPHERIC SOUNDING

Download or read book Advanced atmospheric water vapor DIAL detection system written by and published by DIANE Publishing. This book was released on with total page 155 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Temperature Control of Avalanche Photodiode Using Thermoelectric Cooler written by Tamer F. Refaat and published by . This book was released on 1999 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Optical Engineering written by and published by . This book was released on 2001 with total page 914 pages. Available in PDF, EPUB and Kindle. Book excerpt: Publishes papers reporting on research and development in optical science and engineering and the practical applications of known optical science, engineering, and technology.

Download or read book NASA Langley Scientific and Technical Information Output 2000 written by and published by . This book was released on 2001 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design of Advanced Atmospheric Water Vapor Differential Absorption Lidar DIAL Detection System written by Tamer F. Refaat and published by . This book was released on 1999 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: The measurement of atmospheric water vapor is very important for understanding the Earth's climate and water cycle. The lidar atmospheric sensing equipment (LASE) is an instrument designed and operated by Langley Research Center for high precision water vapor measurements. The design details of a new water vapor lidar detection system that improves the measurement sensitivity of the LASE instrument by a factor of 10 are discussed. The new system consists of an advanced, very low noise, avalanche photodiode (APD) and a state-of-the-art signal processing unit. The new low-power system is also compact and lightweight so that it would be suitable for space flight and unpiloted atmospheric vehicles (UAV) applications. The whole system is contained on one small printed circuit board (9 by 15 cm[squared]). The detection system is mounted at the focal plane of a lidar receiver telescope, and the digital output is read by a personal computer with a digital data acquisition card.

Download or read book Optical Spectroscopic Techniques and Instrumentation for Atmospheric and Space Research written by and published by . This book was released on 1999 with total page 594 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Characterization of a Geiger mode Avalanche Photodiode Detector for High Spectral Resolution Lidar written by Ilya Razenkov and published by . This book was released on 2010 with total page 72 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advanced Water Vapor Lidar Detection System written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-08-10 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the present water vapor lidar system, the detected signal is sent over long cables to a waveform digitizer in a CAMAC crate. This has the disadvantage of transmitting analog signals for a relatively long distance, which is subjected to pickup noise, leading to a decrease in the signal to noise ratio. Generally, errors in the measurement of water vapor with the DIAL method arise from both random and systematic sources. Systematic errors in DIAL measurements are caused by both atmospheric and instrumentation effects. The selection of the on-line alexandrite laser with a narrow linewidth, suitable intensity and high spectral purity, and its operation at the center of the water vapor lines, ensures minimum influence in the DIAL measurement that are caused by the laser spectral distribution and avoid system overloads. Random errors are caused by noise in the detected signal. Variability of the photon statistics in the lidar return signal, noise resulting from detector dark current, and noise in the background signal are the main sources of random error. This type of error can be minimized by maximizing the signal to noise ratio. The increase in the signal to noise ratio can be achieved by several ways. One way is to increase the laser pulse energy, by increasing its amplitude or the pulse repetition rate. Another way, is to use a detector system with higher quantum efficiency and lower noise, on the other hand, the selection of a narrow band optical filter that rejects most of the day background light and retains high optical efficiency is an important issue. Following acquisition of the lidar data, we minimize random errors in the DIAL measurement by averaging the data, but this will result in the reduction of the vertical and horizontal resolutions. Thus, a trade off is necessary to achieve a balance between the spatial resolution and the measurement precision. Therefore, the main goal of this research effort is to increase the signal to noise ratio by a factor of 1...