scholarly journals High Speed Laser Based Intersatellite Link Systems for Harsh Environment of Space

2019 ◽  
Vol 2 (1) ◽  
Keyword(s):  
Fiber Optics ◽  
High Speed ◽  
High Performance ◽  
Low Earth Orbit ◽  
Critical Parameters ◽  
Great Promise ◽  
Harsh Environment ◽  
High Data ◽  
Aerospace Applications ◽  
Laser Communications

This paper will focus on the trends for the space-based lasers, optics and terminals used in the intersatellite networks. Reviewed and evaluate the recent development in the space-based laser technologies and the critical parameters that are employed for successful high-speed intersatellite communications systems. Fiber optics and photonics technology including lasers increasingly being used in aerospace applications and many challenges are involved, since designing for aerospace is very different than for the earth environment. Satellites are much more challenging and for their intersatellite solutions have to contemplate more specific requirements such as space radiation attacks, operation in harsh environment of space and achieving weight, power requirements and reliability for space are few to consider. Therefore it is important to design a system to defend against the radiation from ionizing, gamma, and other attacks. There are numerous methods to protect them from radiation, including shielding, error correction, and using radiation resistance shielding and radiation hardening. Building laser for high speed communications network for the harsh environment of space using optical links in space has proven to be complicated task and many such schemes were tried without success in the past. Space-based optical communications using satellites in low earth orbit (LEO) and Geo-synchronous orbits (GEO) hold great promise for the proposed Internet in the Sky network of the future. However in the last few years, there has been impressive progress made to bring the concept of laser-based intersatellite systems to fruition in civilian and government-non classified projects. Laser communications offer a viable alternative to established RF communications for inter-satellite links and other applications where high performance links are a necessity. High data rate, small antenna size, narrow beam divergence, and a narrow field of view are characteristics of laser-based systems and they are just few numbers of potential advantages for system design over radio frequency communication.

scholarly journals Silicon photonics for high data rate applications -INVITED

2020 ◽  
Vol 238 ◽  
pp. 01005
Author(s):  
David J. Thomson ◽  
Weiwei Zhang ◽  
Ke Li ◽  
Kapil Debnath ◽  
Shenghao Liu ◽  
...  
Keyword(s):  
Silicon Photonics ◽  
High Speed ◽  
High Performance ◽  
High Efficiency ◽  
Electrical Signal ◽  
Electronic Components ◽  
High Data ◽  
Electro Optic ◽  
Optical Domain ◽  
Linear Modulation

The high speed conversion of signals between the optical and electrical domains is crucial for many key applications of silicon photonics. Electro-optic modulators integrated with electronic drive amplifiers are typically used to convert an electrical signal to the optical domain. Design of these individual elements is important to achieve high performance, however a true optimisation requires careful co-design of the photonic and electronic components considering the properties of each other. Here we present our recent results in this area together with a MOSCAP type modulator with the potential for high speed, high efficiency and highly linear modulation.

scholarly journals Design of a Reduced SpaceFibre Interface: An Enabling Technology for Low-Cost Spacecraft High-Speed Data-Handling

Aerospace ◽  
2019 ◽  
Vol 6 (9) ◽  
pp. 101 ◽  
Author(s):  
Gianmarco Dinelli ◽  
Pietro Nannipieri ◽  
Daniele Davalle ◽  
Luca Fanucci
Keyword(s):  
High Speed ◽  
Low Cost ◽  
European Space Agency ◽  
Rate Capability ◽  
Data Rate ◽  
Low Earth Orbit ◽  
Space Applications ◽  
Single Interface ◽  
High Data ◽  
Synthetic Aperture Radars

SpaceFibre is an upcoming on-board high-speed communication protocol for space applications. It has been developed in collaboration with the European Space Agency to answer the growing data-rate requirement of satellite payloads such as Synthetic Aperture Radars or hyper-spectral imagers. SpaceFibre offers a complete set of features (i.e., Fault Detection, Isolation and Recovery, and Quality of Service) that guarantees robust communication at the price of higher complexity. This article proposes an innovative modified implementation of the SpaceFibre standard: R-SpaceFibre. It has been designed to reduce hardware resources while keeping high data-rate capability and flow control. Attention is given to the trade-off between Data link layer complexity reduction and protocol features. The proposed protocol is particularly suitable in scenarios where very low bit error rate is foreseen and data integrity is not critical, for example in imaging instruments. The main advantage is a reduction of more than 40% of logical resources required per single interface. R-SpaceFibre may be a suitable solution for several applications, such as low earth orbit CubeSats, which have strict requirements in terms of available logic resources, mass, volume and cost, and more relaxed constraints in terms of upset immunity.

Design of High Performance Fixed Point CORDIC Processor

2014 ◽  
Vol 998-999 ◽  
pp. 597-601
Author(s):  
Wei Sun ◽  
Jun She An
Keyword(s):  
Fixed Point ◽  
High Precision ◽  
High Speed ◽  
High Performance ◽  
Trigonometric Functions ◽  
Original Design ◽  
Aerospace Applications ◽  
Precision Design ◽  
Transcendental Functions ◽  
Improved Design

To meet the demand for aerospace applications, high-speed computing transcendental functions such as trigonometric functions, we design a high-speed full-parallel CORDIC processor. On this basis,combining the optimized algorithm of simplifing pathway and adding-bits high-precision method , the original design has been improved. The experimental results show that improved design reduces hardware overhead compared to adding-bits high-precision design,and improves accuracy compared to fully parallel design. This high-speed fixed-point CORDIC has high precision and is suitable for high-speed applications in computing trigonometric and inverse trigonometric functions.

scholarly journals Design Scheme of Communication Node Based on FlexRay Bus

2018 ◽  
Vol 214 ◽  
pp. 01001
Author(s):  
Xin He ◽  
Jia’nan Wu ◽  
Hongde Deng ◽  
Zean Zhen ◽  
Chenyang Liu
Keyword(s):  
Flight Control ◽  
Data Transmission ◽  
High Speed ◽  
High Performance ◽  
Transmission Rate ◽  
Serial Communication ◽  
Flight Control System ◽  
Network Systems ◽  
Security Systems ◽  
Aerospace Applications

As a high-speed and reliable serial communication bus, the FlexRay bus has gradually become the mainstream of vehicle network systems. In order to verify the feasibility of the bus technology in aerospace applications, this paper designs a FlexRay communication node based on TI's high-performance microcontroller TMS570LS3137 for security systems. In the whole system, with the DSP of core, the FlexRay communication protocol is achieved by using the bus controller TJA1080 to carry out data transmission. This method is suitable for data transmission of pint and medium-sized UAV (unmanned air vehicles) flight control system with high integration and high transmission rate.

Vacuum System to Minimize the Specimen Contamination of High-Performance EM

1977 ◽  
Vol 35 ◽  
pp. 68-69
Author(s):  
N. Yoshimura ◽  
K. Shirota ◽  
T. Etoh
Keyword(s):  
Electron Microscope ◽  
High Speed ◽  
High Performance ◽  
High Vacuum ◽  
Vacuum System ◽  
Pump System ◽  
Pumping System ◽  
Diffusion Pump ◽  
Almost All ◽  
Cascade Type

One of the most important requirements for a high-performance EM, especially an analytical EM using a fine beam probe, is to prevent specimen contamination by providing a clean high vacuum in the vicinity of the specimen. However, in almost all commercial EMs, the pressure in the vicinity of the specimen under observation is usually more than ten times higher than the pressure measured at the punping line. The EM column inevitably requires the use of greased Viton O-rings for fine movement, and specimens and films need to be exchanged frequently and several attachments may also be exchanged. For these reasons, a high speed pumping system, as well as a clean vacuum system, is now required. A newly developed electron microscope, the JEM-100CX features clean high vacuum in the vicinity of the specimen, realized by the use of a CASCADE type diffusion pump system which has been essentially improved over its predeces- sorD employed on the JEM-100C.

PHAX-SCAN: Functional integration of a Scanning Electron Microscope and an energy-dispersive x-ray analyser

1989 ◽  
Vol 47 ◽  
pp. 56-57
Author(s):  
Marc H. Peeters ◽  
Max T. Otten
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
High Speed ◽  
High Performance ◽  
Functional Integration ◽  
Energy Dispersive ◽  
X Rays ◽  
X Ray ◽  
High Speed Analysis ◽  
Scanning Electron

Over the past decades, the combination of energy-dispersive analysis of X-rays and scanning electron microscopy has proved to be a powerful tool for fast and reliable elemental characterization of a large variety of specimens. The technique has evolved rapidly from a purely qualitative characterization method to a reliable quantitative way of analysis. In the last 5 years, an increasing need for automation is observed, whereby energy-dispersive analysers control the beam and stage movement of the scanning electron microscope in order to collect digital X-ray images and perform unattended point analysis over multiple locations.The Philips High-speed Analysis of X-rays system (PHAX-Scan) makes use of the high performance dual-processor structure of the EDAX PV9900 analyser and the databus structure of the Philips series 500 scanning electron microscope to provide a highly automated, user-friendly and extremely fast microanalysis system. The software that runs on the hardware described above was specifically designed to provide the ultimate attainable speed on the system.

The bright future of digital imaging in scanning electron microscopy

1993 ◽  
Vol 51 ◽  
pp. 768-769
Author(s):  
M. T. Postek ◽  
A. E. Vladar
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Digital Imaging ◽  
High Speed ◽  
High Performance ◽  
Mass Storage ◽  
Analog To Digital ◽  
Central Processing ◽  
Digital Imaging Technology ◽  
Scanning Electron

One of the major advancements applied to scanning electron microscopy (SEM) during the past 10 years has been the development and application of digital imaging technology. Advancements in technology, notably the availability of less expensive, high-density memory chips and the development of high speed analog-to-digital converters, mass storage and high performance central processing units have fostered this revolution. Today, most modern SEM instruments have digital electronics as a standard feature. These instruments, generally have 8 bit or 256 gray levels with, at least, 512 × 512 pixel density operating at TV rate. In addition, current slow-scan commercial frame-grabber cards, directly applicable to the SEM, can have upwards of 12-14 bit lateral resolution permitting image acquisition at 4096 × 4096 resolution or greater. The two major categories of SEM systems to which digital technology have been applied are:In the analog SEM system the scan generator is normally operated in an analog manner and the image is displayed in an analog or "slow scan" mode.

Fundamental Considerations for CDM Failure in 90nm Products

2006 ◽  
Author(s):  
Nobuyuki Wakai ◽  
Yuji Kobira ◽  
Hidemitsu Egawa ◽  
Masayoshi Tsutsumi
Keyword(s):  
Breakdown Voltage ◽  
High Speed ◽  
Gate Oxide ◽  
Critical Parameters ◽  
Protection Device ◽  
Oxide Breakdown ◽  
Technology Products ◽  
Charged Device ◽  
Device Size ◽  
Fundamental Consideration

Abstract Fundamental consideration for CDM (Charged Device Model) breakdown was investigated with 90nm technology products and others. According to the result of failure analysis, it was found that gate oxide breakdown was critical failure mode for CDM test. High speed triggered protection device such as ggNMOS and SCR (Thyristor) is effective method to improve its CDM breakdown voltage and an improvement for evaluated products were confirmed. Technological progress which is consisted of down-scaling of protection device size and huge number of IC pins of high function package makes technology vulnerable and causes significant CDM stress. Therefore, it is expected that CDM protection designing tends to become quite difficult. In order to solve these problems in the product, fundamental evaluations were performed. Those are a measurement of discharge parameter and stress time dependence of CDM breakdown voltage. Peak intensity and rise time of discharge current as critical parameters are well correlated their package capacitance. Increasing stress time causes breakdown voltage decreasing. This mechanism is similar to that of TDDB for gate oxide breakdown. Results from experiences and considerations for future CDM reliable designing are explained in this report.

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