بررسی اثر تابشی دُز یونیزان کل بر عملکرد لیزر محمولۀ لیدار هواشناسی (فضایی): طراحی سیستمی ماهوارۀ سنجش از دور در مدار LEO

نویسندگان

1 استادیار، پژوهشکدۀ سامانه‌های ماهواره، پژوهشگاه فضایی ایران، تهران، ایران

2 مربی، پژوهشکدۀ سامانه‌های ماهواره، پژوهشگاه فضایی ایران، تهران، ایران

3 پژوهشگر، پژوهشکدۀ سامانه‌های ماهواره، پژوهشگاه فضایی ایران، تهران، ایران

چکیده

تابش‌های محیط فضا بر عملکرد و طول عمر قطعات اپتیکی و الکترونیکی محمولۀ ماهواره‌ها تأثیرگذار است.در این پژوهش، اثرآسیب تابشی دُز یونیـزان کل بر عملکرد زیرسیستم لیزر محـمولۀ لیداریک ماهواره، ‌در مدار 500 کیلومتری، با مأمـوریت سه‌ساله، شبیه‌سازی شده است. شبیه‌سازی‌های تابشی بر روی دو قسمت محیط بهره و پمپ با استفاده از برنامه‌نویسی C++ در جعبه ابزار GEANT4انجام گرفته است. نتایج شبیه‌سازی‌ها نشان می‌دهد دُز تابشی دریافت‌شده در قسمت محیط‌بهره، در حالت بدون محافظ، برابر با rad 1951 است و این در حالی است که دُز القایی با در نظر گرفتن شیلد آلومینیومی با ضخامت2 میلی‌متر به حدود rad 275 برای محیط بهره و حدود rad 623 برای پمپ لیزر کاهش می‌یابد. همچنین براساس محاسبات، با در نظرگرفتن مدت زمان مأمـوریت و مـساحت جانبی، حـجم حـساس به تابش تعداد ذرات برخوردکننده برابر با 1012×7 خواهد بود. نتایج شبیه‌سازی نشان می‌دهد اثر تابشی دُز یونیزان کل بر بخش لیزر باعث افزایش15 درصدی جریان آستانه و کاهش توان اپتیکی می‌شود.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Effect of Total Ionizing Dose Damage on Laser Subsystem of Space LIDAR payload: System Level Design of Remote Sensing Satellite

نویسندگان [English]

  • Masoud Khoshsima 1
  • Reza Amjadifard 2
  • Sasan Zamani Moghadam 3
  • Sajjad Ghazanfarinia 3
1 Assistant Professor, Satellite Research Institute, Iranian Space Research Center, Tehran, Iran
2 Lecturer, Satellite Research Institute, Iranian Space Research Center, Tehran, Iran
3 Researcher, Satellite Research Institute, Iranian Space Research Center, Tehran, Iran
چکیده [English]

Space environment radiation affects the operation and life-time of optical and electronic devices on satellites payloads. LIDAR payloads include electro-optical components such as laser section. LIDAR payloads are usually setup on various platforms. Space-borne remote sensing technology provides global data set of uniform quality and rapid data acquisition and also specially provides key information for evaluating the local, regional of aerosol irradiative forcing in global climate system, cloud properties and precipitation, Air pollution and hydrologic cycle. Also, global coverage collected data is updated in every time range. On the other hand, high expenditures of design, manufacture and using advanced technology are caused an increase in design and manufacture of high reliability LIDAR payloads, the mission duration and its quality in space. Due to space standards of NASA and ESA, one of the effective factors on degradation of space systems is radiation damages. In this research, effect of Total Ionizing Dose (TID) radiation on the operation of LIDAR subsystem orbiting 500 km altitude orbit with a 3-year mission is simulated. Radiation simulations on gain medium (Nd:YAG) and pump (laser diode) are performed by GEANT4 and C++ programming.
Laser subsystem in LIDAR payload includes 3 different parts. These parts are Nd:YAG, mirrors and laser diodes pump. Space radiation sources are classified in three types: Van Allen radiation belts, Galactic cosmic rays (GCR), periodic gradual activities of sun. The sun emits neutralized plasma (almost protons and electrons) to the space. Some energetic particles originated from solar winds and GCRs are trapped in Earth magnetic field. These belts are expanded from 1000km to 65000 km and consist of electrons up to 7Mev and protons up to 300Mev. GCR particles are mainly protons with very high speed originated from out of the galaxy. The most populated particles in 500km altitude are electrons and protons. In order to simulate the radiation effects, Input data such as average flux number of incident particles, total number of particles passing through the sensitive volume are needed. These input data will be entered in GEANT4 toolkit by C++. Most important input data are flux, total number of incident particles during the mission, Energy range, geometry, materials definition and their properties, sensitive volume definition are needed physics and initial position of particles. The most important radiation damages related to lasers and solid state optical devices are total ionizing dose and displacement damage. TID is resulted from passing charged particles through matter, while displacement damage is due to collision of passing particles with atoms of matter. TID effects depend on two factors. The first factor is generation of electron-hole pairs in dielectric layers (such as oxides). The second factor is trapping sites (oxide and interface). This damage results in degradation and possible failure, such as threshold voltage shift, decrease in drive current, switching frequencies, leakage current, noises, etc. In bipolar transistors, hfe degradation, leakage current, offset voltage, changes in offset current, bias current and gain degradation in analog devices are possible effect. In other devices, frequency shift in crystals, mechanical degradations and changes in dielectric parameters are considered.
The results demonstrated that the absorbed dose from different space radiation sources for Nd:YAG and laser diode are important. Also, differences between the absorbed doses in 2 cases were simulated. The first case was absorbed dose with no shield against space radiation and the second one was calculating the absorbed dose with 2 mm Al7075 shielding the sensitive volumes against incoming particles. GEANT4 simulations determined that the absorbed dose in Nd:YAG when no shield was used to protect the laser parts against space radiation, was reached 1951 rad. In order to decrease the absorbed dose, the shield was used and it made considerable changes. The absorbed dose was reduced to 275 rad. Calculation showed that approximately 7×1012 protons would pass through the Nd:YAG, during the mission period. The number of passing particles through the sensitive volume depends on particle flux rate, sensitive volume sizes, mission duration. This value for GCR particles was 4×108 particles in each square centimeter. Results related to simulation of inner Van Allen radiation belt particles effect on Nd:YAG showed that the absorbed doses from the inner belt electrons and protons were about 68 rad and 187.5 rad respectively while these values for GCR protons and alpha particles were about 11 rad and 8.5 rad respectively. These values were about 481 rad, 128.5 rad, 7.5 rad and 6 rad for laser diode respectively. The total values for Nd:YAG and laser diode reached 275 rad and 623 rad. It is estimated that absorbed doses for radiation sensitive parts will be increased about 15 percent and according to the threshold current, the optical power versus threshold current curve will be changed.

کلیدواژه‌ها [English]

  • Laser
  • Nd:YAG
  • Space radiation
  • Total Ionizing Dose
  • LiDAR
علیایی، س. و قهرمانی‌راد، ا.، 1394، مهندسی لیزر و مخابرات نوری فضای آزاد، انتشارات دانشگاه تربیت دبیر شهید رجایی.
Afzal, S. R, 2006, Review of solid-state lasers for space applications, Proceedings Volume 6100, Solid State Lasers XV: Technology and Devices; 61001U (2006); doi: 10.1117/12. 660699.
ECSS-E-HB-10-12A, 2010, European Cooperation for Space Standardization, 25-50.
ECSS-Q-ST-60-15C-1, 2012, Space product assurance Radiation hardness assurance - EEE component, 14-33.
Gill, K., Arbet-Engels, V., Batten, J., Cervelli, G., Grabit, R., Mommaert, C., Stefanini, G., Troska, J. and Vase, F., 1997, Radiation damages studies of optoelectronic components for the CMS tracker optical links, Radiation and Its Effects on Components and Systems, RADECS 97, Fourth European Conference on. DOI: 10.1109 / RADECS. 1997.698956.
Grupen, C., 2010, Introduction to Radiation Protection: practical knowledge for handling radiative sources, Springer science & Business media, 410-453.
Houghton, J., 2002, The physics of atmospheres. 275.
Johnson, A. H., 2003, Radiation effects in light-emitting and laser diode, IEEE Transactions on nuclear science, 50, 126-141.
Johnson, A. H. and Miyahira, T. F., 2004, Radiation Degradation Mechanisms in laser diodes, in IEEE Transactions on Neclear science, 51(6), 3564-3571.
Myers, T. L., 2015, Proton and gamma irradiation of  Fabry-Perot quantum cascade lasers for space qualification", Optical Society of America, 440-451.
Ott, M. N., 2000, Validation of Commercial Fiber
Optic Components for Aerospace  Environments, misspiggy. gsfc.nasa. gov/ photonics, NASA Goddard Space Flight Center Greenbelt MD, 20771.
Ott, M. N., coyle, N., John S., Canham, H., leidecker, W., 2006, Qualification and issues with Space Flight Laser Systems and Components, lasers and applications in science and engineering, International society for optics and photonics,  https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20060013395.pdf.
Phifer, C., 2004, Effects of Radiation on Laser Diodes, United states, Department of Energy, Technical Report.38-44.
Roner.M.,2015, Total Ionizing Dose and Displacement  Damage effects in a tunable laser diode based fiber optic sensing system, IEEE, Radiation and its effects on components and systems, Russi,DOI: 10.1109/RADECS.2015.7365688.
Rose, T. S., Hopkins, M. S. and Fields, R.A., 1995, Characterization and control of Gamma and proton radiation effects on the performance of  Nd:YAG  and Nd:YLF laser, IEEE Journal of quantum Electronics, 31(9), 1593 – 1602.
Spohn, T., Breuer, D., Johnson, T., 2014, Encyclopedia of the solar system ,Elsevier, 3rd edition,  11-68.