Feed aggregator

Publication date: 1 January 2025

Source: Advances in Space Research, Volume 75, Issue 1

Author(s): Uzair Majeed, B. Ramzan

Publication date: 1 January 2025

Source: Advances in Space Research, Volume 75, Issue 1

Author(s): Kalpesh Ghag, Anil Raghav, Zubair Shaikh, Georgios Nicolaou, Omkar Dhamane, Mohit Shah, Utsav Panchal, Prathmesh Tari, Kishor Kumbhar

Publication date: 1 January 2025

Source: Advances in Space Research, Volume 75, Issue 1

Author(s): Xumin Sun, Rui Zhang, Hua Zhang, Zhenyu Hu, Weijun Wang, Meng Zou

Publication date: 1 January 2025

Source: Advances in Space Research, Volume 75, Issue 1

Author(s): Axel Bouquety, Lucile Fayon, Detlef Koschny, Robin Narbey, Tomaso R.R. Bontognali, Laurent Jorda, Marie Josset, Gabriela Ligeza, Nikolaus Kuhn, Jean-Luc Josset

Publication date: 1 January 2025

Source: Advances in Space Research, Volume 75, Issue 1

Author(s): Chukwuebuka J. Ugwu, Jibrin A. Alhassan, Ogbonnaya Okike, Firew M. Menteso, Ngozi M. Ugwu, Augustine E. Chukwude, Evaristus U. Iyida, Innocent O. Eya, Romanus E. Ugwoke, Dominic C. Obiegbuna, Finbar C. Odo, Orji P. Orji

Publication date: 1 January 2025

Source: Advances in Space Research, Volume 75, Issue 1

Author(s): Hongyang Zhao, Jing Jin, Xingdong Li, Yi Liu, Yanan Guo

Publication date: 1 January 2025

Source: Advances in Space Research, Volume 75, Issue 1

Author(s): Vinay Kumar Gundeboina, Shanti Priya Devarapalli, Rukmini Jagirdar

Publication date: 1 January 2025

Source: Advances in Space Research, Volume 75, Issue 1

Author(s): V.G. Lozitsky, I.I. Yakovkin, N.I. Lozitska

Publication date: 1 January 2025

Source: Advances in Space Research, Volume 75, Issue 1

Author(s): Predrag Jovanović, Saša Simić, Vesna Borka Jovanović, Duško Borka, Luka Č. Popović

The Vrancea Seismic Zone (VSZ) is an atypical intermediate-depth earthquake nest located in the South-East Carpathians in Romania, often regarded as a relic slab sinking into the mantle. The origin of the slab...

Abstract

The process of forming edge metallization on input windows (germanium, silicon, and other discs) used for introducing the received light flux into a photodetector housed in a protective hermetic casing is being investigated. This work presents the results of an experimental study on the dependence of the edge metallization profile of Ge discs, formed by magnetron sputtering, on the design parameters of the loading device. Various designs of loading devices are presented. The experimental results demonstrate the influence of thickness on the edge metallization profiles of the components of the loading device that mask the discs during sputtering.

Abstract

Methods to solve the problem of traceability and reproducibility for the measurement of parameters of second-generation photodetectors are proposed. An improved block diagram of the measurement methods and division into groups of the methods for measurement of second-generation photodetector devices and monitoring of auxiliary equipment is presented.

Abstract

Effect of illumination distribution in the circle of confusion on the measurement of the photoelectric coupling coefficient of the second-generation photodetector devices is studied. A theoretical study is carried out using mathematical modeling for illumination patterns of different structure and several ratios of photodetector pitch to the effective size of the photosensitive area. A formula is derived for calculation of the photoelectric coupling coefficient for a known distribution of photodetector sensitivity. The main conditions that affect the reliability of the results on the simulated measurement process are presented.

Abstract

Distributions of dark currents, lifetimes of minority carrier, and microdefects revealed by selective etching are compared. The main reason for increased dark currents and decreased photosensitivity in silicon photodiodes fabricated on n-type silicon using the Czochralski method are the generation–recombination processes on fine oxide precipitates.

Abstract

The results of the development of a recursive algorithm for temporal noise reduction with an adaptive threshold for thermal imaging systems are presented. This algorithm is designed to reduce the level of temporal noise based on the results of analyzing a sequence of images obtained using a thermal imaging channel. A mathematical model of the algorithm is provided, as well as the required amount of computing resources needed for its hardware implementation in field programmable gate arrays (FPGAs). Several characteristics of the thermal imaging system with the developed algorithm were measured and conclusions were made about the positive influence of the algorithm on its noise equivalent temperature difference (NETD).

Abstract

The resonant scattering spectra by the main magnetic mode of a subwavelength linear structure consisting of two dielectric flat thin rings located along the wave vector and excited by the displacement currents of the incident plane electromagnetic wave of the microwave range are investigated experimentally and using computer modeling. As distinct from a single ring, splitting of the resonant frequency is observed in the scattering spectra of the magnetic field in the far wave zone, near wave zone, and near the centers of the rings. The measured spectra coincide with the spectra resulting from computer calculations at all measurement points.

Abstract

For the task of Earth remote sensing (ERS) in the short-wave infrared (IR) range of the spectrum, the most promising are matrix and multi-row photodetector modules of the short-wave infrared (IR) range of the spectrum based on heteroepitaxial structures of materials of the ternary solution of cadmium-mercury-tellurium (HgCdTe) and the ternary solution of indium-gallium-arsenide (InGaAs), sensitive in the spectral range from 1 to 2.5 μm. Possible architectures of photosensitive elements that provide reduced dark currents and noise are analyzed. Ways of improvement are considered and dark currents and parameters of n-on-p-type heterostructures based on HgCdTe in a wide temperature range, as well as the parameters of p+-B–n-N+-type barrier structures based on InGaAs are investigated.

Abstract

An overview of various sensor designs for recording the parameters of microparticles in the accelerator path is provided, which are used to simulate the impact of micrometeoroids and space debris particles on structural elements of a spacecraft. A model of a cylindrical induction sensor (a Faraday cup) and a possible modification of its design for measuring the microparticle distribution in the accelerator path are considered in more detail.

Abstract

The parameters of photodetectors based on photosensitive barrier structures and photodiodes with absorbing layers of InAs1–xSbx and In1–xGaxSb ternary solutions of the mid-wave infrared spectrum range are studied. Temperature dependences of lifetime and dark current in InAs1–xSbx and In1–xGaxSb layers have been calculated. The signal-to-noise ratio in the operating temperature range was determined. Parameter modeling has shown that for photodetectors based on InAs0.8Sb0.2 with a cutoff wavelength λ0.5 ∼ 4.8 µm the detectability at T = 100 K will be D* ≈ 1012 cm W–1 Hz1/2; for photodiodes based on In0.7Ga0.3Sb with cutoff wavelength λ0.5 ∼ 5.2 µm the detectability at T = 100 K will be D* ≈ 1011 cm W–1 Hz1/2, which is suitable for high temperature applications.