Wide-area digital transmission facility used predominantly in Europe that carries data at a rate of 2.048 Mbit/s.
Wide-area digital transmission facility used predominantly in Europe that carries data at a rate of 34.368 Mbit/s.
The term used to describe the combination or antenna, low-noise amplifier (LNA), down-converter, and receiver electronics. used to receive a signal transmitted by a satellite. Earth Station antennas vary in size from the.2 foot to 12 foot (65 centimeters to 3.7 meters) diameter size used for TV reception to as large as 100 feet (30 meters) in diameter sometimes used for international communications. The typical antenna used for INTELSAT communication is today 13 to 18 meters or 40 to 60 feet.
An electronic circuit which attenuates or eliminates the echo effect on satellite telephony links. Echo cancellers are largely replacing obsolete echo suppressors.
A time-delayed electronic reflection of a speaker's voice. This is largely eliminated by modern digital echo cancellers.
When a satellite passes through the line between the earth and the sun or the earth and the moon.
Refers to a transponder that can remain powered during the period of an eclipse.
An antenna mount providing independent adjustments in elevation and azimuth.
Edge of Coverage
Limit of a satellite's defined service area. In many cases, the EOC is defined as being 3 dB down from the signal level at beam center. However, reception may still be possible beyond the -3dB point.
Effective Isotropic Radiated Power - This term describes the strength of the signal leaving the satellite antenna or the transmitting earth station antenna, and is used in determining the C/N and S/N. The transmit power value in units of dBW is expressed by the product of the transponder output power and the gain of the satellite transmit antenna.
The upward tilt to a satellite antenna measured in degrees required to aim the antenna at the communications satellite. When. aimed at the horizon, the elevation angle is zero. If it were tilted to a point directly overhead, the satellite antenna would have an elevation of 90 degrees.
A device used to electronically alter a signal so that it can only be viewed on a receiver equipped with a special decoder.
A low-frequency waveform combined with the baseband signal prior to modulation, to spread the FM signal's peak power across the available transponder bandwidth in order to reduce the potential for creating interference to ground-based communications services.
End of Life of a satellite.
An orbit with a plane parallel to the earth's equator.
Engineering Service Circuit - The 300-3,400 Hertz voice plus teletype (S+DX) channel used for earth station-to-earth station and earth station-to-operations center communications for the purpose of system maintenance, coordination and general system information dissemination. In analog (FDM/FM) systems there are two S+DX channels available for this purpose in the 4,000-12,000 Hertz portion of the baseband. In digital systems there are one or two channels available which are usually convened to a 32 or 64 Kbps digital signal and combined with the earth station traffic digital bit stream. Modern ESC equipment interfaces with any mix of analog and digital satellite carriers, as well as backhaul terrestrial links to the local switching center.
The European Telecommunications Satellite Organization which is headquartered in Paris, France. It provides a satellite network for Europe and parts of North Africa and the Middle East.


Aberration-Corrected Imaging in Transmission Electron Microscopy
- About the Author
This book provides a concise introduction to practical aspects of atomic-resolution imaging in aberration-corrected electron microscopy. As such, it addresses recent advances in electron optical instrumentation used for ultra-high resolution imaging in materials and nano-science.
It covers two of the most popular atomic resolution imaging techniques' namely high-resolution transmission electron microscopy and scanning transmission electron microscopy. The book bridges the gap between application-oriented textbooks in conventional electron microscopy and books in physics covering dedicated topics in charged-particle optics and aberration correction.
The book is structured in three parts which can be read separately. While in the first part the fundamentals of the imaging techniques and their limits in conventional electron microscopes are explained, the second part provides readers with the basic principles of electron optics and the characteristics of electron lenses. The third part, focusing on aberrations, describes the functionality of aberration correctors and provides readers with practical guidelines for the daily work with aberration-corrected electron microscopes. The book represents a detailed and easy readable guide to aberration-corrected electron microscopy.
Rolf Erni studied materials science and received his doctoral degree from the Swiss Federal Institute of Technology Zurich (ETH Zurich) at the (formerly) Institute of Applied Physics. Thereafter he carried out postdoctoral studies at the University of California at Davis and at the National Center for Electron Microscopy (NCEM), Lawrence Berkeley National Laboratory. He then joined FEI Company as an application specialist and was later in the role of a system engineer. Before returning to NCEM as a staff scientist, he spent a period of time as a faculty member at the EMAT institute (Electron Microscopy for Materials Science) of the University of Antwerp. Since 2009, Rolf is head of Empa's Electron Microscopy Center
Cover Type: Hardcover
Page Count: 348
Year Published: 2010


Fiber optics are a cutting-edge technology that has revolutionized the way we transmit data, voice, and video signals. These cables are made of incredibly thin strands of glass or plastic, and they use the principle of total internal reflection to transmit data using light signals. This makes fiber optics capable of carrying information over long distances with minimal loss of signal strength.
The Advantages of Fiber Optic Cables
Fiber optic cable offers several significant advantages over traditional copper cables, making them the preferred choice for high-speed data transmission. One of the key advantages is their ability to transmit data at lightning-fast speeds.
Lightning-Fast Speeds for Internet Connectivity
One of the primary reasons why fiber optics are gaining popularity is their unmatched speed. Fiber optics can transmit data at the speed of light, which is significantly faster than the speeds achievable with copper cables. This results in lightning-fast internet connectivity, allowing for quick and seamless online experiences.
With fiber optics, you can enjoy faster download and upload speeds, smoother video streaming, lag-free online gaming, and quicker data transfers. This is especially crucial in today’s digital world, where fast and reliable internet connectivity is essential for various activities, such as remote work, online education, streaming content, and more.
Enhanced Reliability and Signal Quality
Fiber optics are also known for their enhanced reliability and signal quality. Unlike copper cables, which are susceptible to interference from various sources, such as electromagnetic interference (EMI) and radio-frequency interference (RFI), fiber optics are immune to these types of interference. This results in a more stable and consistent internet connection, with minimal disruptions and signal degradation.
Fiber optics are also less prone to attenuation, which is the loss of signal strength over long distances. This means that data can be transmitted over longer distances without the need for repeaters or signal boosters, making fiber optics ideal for long-haul data transmission.
Furthermore, fiber optics are resistant to environmental factors, such as moisture, temperature fluctuations, and corrosion, which can degrade signal quality in copper cables. This makes fiber optics more reliable and durable, ensuring consistent performance even in challenging conditions.
Future-Proofing Your Connectivity
Another significant advantage of fiber optics is that they are future-proof, meaning they are capable of handling increasing data demands in the future. As technology continues to advance and data requirements continue to grow, fiber optics can provide the necessary bandwidth and speeds to meet these demands.
Fiber optics have a much higher bandwidth capacity compared to copper cables, allowing for the transmission of large amounts of data simultaneously. This makes them well-suited for applications that require high bandwidth, such as cloud computing, virtual reality, and the Internet of Things (IoT).
Investing in fiber optics for your internet connectivity is a future-proof solution that can ensure your network can handle the ever-increasing data demands of the modern world without the need for costly upgrades or replacements in the near future.
Wide Range of Applications
Fiber optics are widely used in various industries, including telecommunications, internet service providers (ISPs), data centers, and more. They are increasingly becoming the preferred choice for high-speed internet connectivity due to their numerous advantages over traditional copper cables.
Long-Term Economic Benefits
In addition to their technical advantages, fiber optics also offer economic benefits. While the initial installation costs of fiber optics may be higher than traditional copper cables, the long-term benefits and cost savings outweigh the initial investment. Fiber optics require less maintenance, have longer lifespans, and can result in lower energy consumption, making them a cost-effective solution in the long run.
Getting Started With Fiber Optics Wifi
Fiber optics WiFi, also known as fiber-to-the-home (FTTH) or fiber-to-the-premises (FTTP) internet service, requires professional installation due to the complexity and specialized equipment involved. Contact the internet service providers in your area to check if they offer FTTH or FTTP service and if it is available at your location. ISPs typically have online tools or customer service representatives who can provide information about service availability.
In conclusion, fiber optics are revolutionizing the way we transmit data, voice, and video signals, providing lightning-fast speeds for internet connectivity. Their unmatched speed, enhanced reliability, signal quality, and future-proofing capabilities make them the ideal choice for high-speed data transmission.


Our understanding of the fate and distribution of micro- and nano- plastics in the marine environment is limited by the intrinsic difficulties of the techniques currently used for the detection, quantification, and chemical identification of small particles in liquid (light scattering, vibrational spectroscopies, and optical and electron microscopies). Here we introduce Raman Tweezers (RTs), namely optical tweezers combined with Raman spectroscopy, as an analytical tool for the study of micro- and nanoplastics in seawater. We show optical trapping and chemical identification of sub-20 μm plastics, down to the 50 nm range. Analysis at the single particle level allows us to unambiguously discriminate plastics from organic matter and mineral sediments, overcoming the capacities of standard Raman spectroscopy in liquid, intrinsically limited to ensemble measurements. Being a microscopy technique, RTs also permits one to assess the size and shapes of particles (beads, fragments, and fibers), with spatial resolution only limited by diffraction. Applications are shown on both model particles and naturally aged environmental samples, made of common plastic pollutants, including polyethylene, polypropylene, nylon, and polystyrene, also in the presence of a thin eco-corona. Coupled to suitable extraction and concentration protocols, RTs have the potential to strongly impact future research on micro and nanoplastics environmental pollution, and enable the understanding of the fragmentation processes on a multiscale level of aged polymers.
Raman, Microplastic, Nanoplastic, Seawater
Gillibert, R., Balakrishnan, G., Deshoules, Q., Tardivel, M., Magazzù, A., Donato, M. G., Maragò, O. M., Lamy de La Chapelle, M., Colas, F., Lagarde, F., Gucciardi, P. G., 2019. Raman Tweezers for Small Microplastics and Nanoplastics Identification in Seawater. Environmental Science & Technology 53, 9003-9013.


The National MagLab site at the McKnight Brain Institute hosted five scientists from across North America in June to teach the theory and practice of radio frequency (RF) coils.
RF coils are used in magnetic resonance imaging (MRI) to transmit and receive RF signals. The MagLab’s Advanced Magnetic Resonance Imaging and Spectroscopy (AMRIS) facility at UF has an entire lab devoted to RF coil manufacture and development, led by RF engineer Malathy Elumalai.
In response to a growing need for visiting scientists to be able to troubleshoot and design their own RF coils, Elumalai is sharing her expertise. Empowering scientists to make their own coils makes sense. The demand for specialized coils has outpaced the rate at which Elumalai can design them. Additionally, sometimes the coils break, causing an experiment to come to a halt.
At the workshop from June 20 to 24, participants learned the physics behind RF coils and underwent training in specialized software for designing and modeling how the coils will behave under different magnetic fields and with different samples. Participants also had the chance to build their own coil and test it in the MagLab’s 4.7 tesla imaging magnet.
How do RF coils in MRI machines work? First, the coil transmits an RF signal, which produces a magnetic field perpendicular to the one already being produced by the magnet. Then, the same RF coil (or a separate one) receives signals indicating how the nuclear spins inside the subject are relaxing. This information is then processed as an image. Without RF coils, there’d be no “I” (imaging) in MRI!
The workshop is an example of the ongoing training we offer our “users” so that they can make the most of their time with our magnets. The MagLab also offers a User Summer School and a Theory Winter School once a year.
Text and image by Elizabeth Webb.


The REIL system is used to identify the threshold (approach end) of a visual or instrument non-precision runway and provides guidance to pilots during approach for landing. The Runway End Identification Light consists of two unidirectional simultaneous flashing lights. A light is located at each side of the runway threshold. The lights have a beam coverage of 10° vertically and 30° horizontally with a flash rate of two flashes per second. The REIL meets the photometric beam requirements for MALSR, SSALR and ALSF-I/II.
The integrated solar module and battery system offers considerable savings in power and installation costs. The solar module can be angled to maximise solar collection to charge the battery. Contact your Avlite representative to determine the solar system suitable for your location.
- Long LED life
- Low Power Draw – entire system draws less than 40 Watts
- Improved safety – low voltage 24 VDC model
- Nominal intensity – 15,000 effective candelas
- Beam Coverage – 10° vertically, 30° horizontally
- Flash rate: two flashes per second
- Separation: Control unit can be mounted in excess of 500 feet from flash head
- Remote Control: ON/OFF, 3-step intensities
- Meets photometric beam requirements for MALSR, SSALR, and ALSF-I / II
- Voltage-powered- 24VDC solar powered


Two state-of-the-art wind turbine drivetrain test facilities are now open for business: the Clemson University Wind Turbine Drivetrain Testing Facility in South Carolina and a National Renewable Energy Laboratory dynamometer at the National Wind Technology Center in Colorado. The two test facilities will be used to evaluate in a controlled environment the mechanical systems that convert the aerodynamic forces of wind turbine blades into electricity from a generator. Funded in part by the Energy Department (DOE) through the American Recovery and Reinvestment Act, the new facilities will help accelerate the development and deployment of next-generation technologies for both offshore and land-based wind energy systems.
Former military base now home to advanced wind facility
Located on the site of a former Navy base with easy access to both rail and deepwater transport, the Clemson facility in North Charleston is ideal for testing the large, commercial scale turbines being developed by manufacturers for offshore wind farms. This facility, which opened last week, is equipped with 7.5-megawatt (MW) and 15-MW dynamometers that will enable the wind industry and testing agencies to verify the performance and reliability of drivetrain prototypes and commercial machines by simulating operating field conditions in a laboratory environment. Verifying a wind system’s performance before it is commercially deployed reduces risk for both the manufacturer and system operator, and facilities like Clemson’s can simulate as much as 20 years’ worth of wear and tear on drivetrains in a few months.
In addition to testing the performance of the drivetrains, Clemson is using the facility’s electrical infrastructure to build a 15-MW hardware-in-the-loop grid simulator. The grid simulator will mimic real-world circumstances, such as wide-area power disruptions, frequency fluctuations, voltage drops, cascading accidents, and cyber or physical attacks, to determine the effects of wind turbines on utility grids and grids on wind turbines.
Gaining insight through expertise
DOE’s second new test facility at NREL’s National Wind Technology Center near Boulder, which also opened last week, offers industry the capability to perform accelerated tests on wind turbine drivetrains with capacity ratings of up to 5-MW. In addition, industry partners that use the facility gain access to on-site engineers with more than three decades of engineering experience.
NWTC now has two dynamometers that can be connected either directly to the grid or to a controllable grid interface (CGI). The dynamometer and CGI work in tandem to provide engineers with a better understanding of how wind turbines react to grid disturbances. With these additions, the NWTC is one of the only facilities in the world that can use these capabilities alongside operating multi-megawatt wind turbines in the field at the NWTC and energy storage devices undergoing testing there.
Watch the video above to find out how the dynamometer and the CGI work. Read this factsheet for more information about the new NREL facility.
The two facilities are part of DOE’s overall strategy to increase the amount of electricity generated from renewable sources such as wind, reduce harmful greenhouse gas emissions, and create a more sustainable future for generations to come.


A heat exchanger is a system used to transfer heat between two or more fluids. Heat exchangers are used in both cooling and heating processes. The fluids may be separated by a solid wall to prevent mixing or they may be in direct contact. They are widely used in space heating, refrigeration, air conditioning, power stations, chemical plants, petrochemical plants, petroleum refineries, natural-gas processing, and sewage treatment. The classic example of a heat exchanger is found in an internal combustion engine in which a circulating fluid known as engine coolant flows through radiator coils and air flows past the coils, which cools the coolant and heats the incoming air. Another example is the heat sink, which is a passive heat exchanger that transfers the heat generated by an electronic or a mechanical device to a fluid medium, often air or a liquid coolant.
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Senior Research Optical Engineer
Avegant is a well-funded, venture-backed technology company developing next-generation display technology to enable previously impossible augmented reality experiences. We are pioneering innovative hardware and software solutions that will forever change how we learn, play, work and interact with each other. We’ve won multiple awards, our team is best in class, and we’re just getting started.
Avegant is about the journey of innovation, together as a team. Interested in joining us?
Avegant is seeking a Senior Optical Engineer to contribute to our cutting-edge near eye display technology. The position will be filled by a highly-motivated individual with at least 5 years of experience in a design and production environment. This position will be responsible for working with technical team members in the development and evaluation of new optical technologies, architectures, components, and assembly concepts for near-eye display systems. This is a great opportunity to be a part of a revolutionary technology in a fast-growing field. This position will work closely with our mechanical engineering, optical and industrial design teams. This position reports to the Chief Technology Officer. The job is based in Belmont, CA, and requires that you be onsite and not remote.
• Support product development with imaging system optical designs, component selection, and tolerance analysis
• Work with suppliers on custom or semi-custom component selection, specification, and qualification
• Assembly and evaluation of prototype assemblies – specifically evaluating optical characteristics, image quality (MTF), light polarization measurement, thermal characteristics
• Work with suppliers to define, specify, and evaluate optical coating performance on prototype components
• Maintain detailed laboratory notes of the results of various evaluation experiments
• Provide analysis of results of experiments for test samples
• Evaluate new test/process equipment and tools and make recommendations to management
• Maintain database of laboratory test results that can be accessed for comparison of data from various evaluation samples
• Provide documentation of prototype assembly procedures that can be used for subsequent manufacturing process documentation
• Bachelor’s Degree in optical engineering or similar; Master’s degree or PhD preferred
• 5 – 10 years’ work experience in optical design, including design of imaging systems, especially for image projection
• Experience with optical design software such as Zemax and FRED, including tolerance analysis and stay light modeling
• Experience with optical system assembly methods and materials
• Familiarity with the tools and techniques need to characterize optical systems, including resolution, distortion, field curvature and colorimetry
• Experience with waveguide optics a plus
• Experience with holographic or diffractive optics a plus
• Experience with Solidworks a plus
• Experience with the transfer of new designs and processes to manufacturing a plus


PRECISION LAND MANAGEMENT
INTELLIVIEW IV DISPLAY
The IntelliView III colour touchscreen monitor is your partner in all farming operations and is available on the T6 Auto Command and T7. The T8 and T9 tractor ranges, CR combines harvester range along with the BigBaler & Speedrower® Self-propelled Windrower ranges are fitted standard with the new widescreen IntelliView IV colour touchscreen monitor. The IntelliView IV can be used as a second screen for precision farming applications on T7, T8 and T9 tractor ranges and CR combine harvesters. Both the IntelliView III and IntelliView IV displays communicate directly with the IntelliSteer™ system together with the machine’s CAN Bus, and display key operating parameters in real time on just one screen. Maximum operator comfort is guaranteed thanks to the intuitive operating logic which enables you to see just where you are, and enables you to select the precise information you wish to browse, monitor and control.
EZ-GUIDE® 250 DISPLAY
The EZ-Guide® 250 is an easy to use and affordable tool that offers up to +/-45cm pass-to-pass accuracy. The built in OnPath® filter technology provides improved pass-to-pass accuracy and the EZ-Guide® 250 is compatible with all makes and models of equipment.
The FM-750 is a multi-function display, and has a built-in receiver that allows you to choose the accuracy your application requires from +/-20cm to +/-2.5cm pass-to-pass and year-on-year. When you need a DGPS guidance system that saves you time, fuel and inputs, look no further than the FM-750.
The ultra-wide screen XCN-2050™ display is compatible with the full range of correction signals and offers intuitive, colour multi-touchscreen operation. It has been designed to ensure full integration with advanced PLM™ technology including yield and moisture sensing, as well as a whole range of other precision guidance applications.


Hemisphere A25 Survey Grand GNSS Antenna for Land and Marine Applications
This low profile multipurpose antenna has a unique filtering pattern. Precise attention has been paid to mitigation of multipath interference.
The A25 GNSS antenna has been designed to support millimeter accuracy on land and marine applications. The A25 offers support for present and future GNSS signals, including GPS, GLONASS, BeiDou, and Galileo. A25 is a multi-GNSS precision antenna and is ideal for various applications including surveys, single-frequency RTK positioning and navigation, precise guidance, and machine control.
This antenna has been designed to excel in challenging environments (such as near buildings and foliage). The A25 is designed for multipath mitigation, stable phase center and strong SNRs, even at low elevations. The rugged housing is made of an aluminum base that has been pretreated for the marine environment and will withstand salt, fog, and spray.
The durable A25 antenna easily passes the two-meter pole drop test.
- GNSS Reception: GPS L1, GLONASS G1, BeiDou B1, Galileo E1, SBAS, and L-band
- GNSS Frequency: 1.525 to 1.615 GHz
- LNA Gain: 30 dB
- LNA Noise: 2.0 dB, typical
- L-Band Frequency: 1.525 – 1.585 GHz
- L-Band LNA Gain: 30 dB
- Input Voltage: 3.3 to 12 VDC
- Input Current: 12 mA, typical
- Enclosure: Aluminum base with ASA plastic cap
- Dimensions: 4.7 H x 15.2 D (cm); 1.8 H x 6.0 D (in)
- Weight: .40 kg (.88 lbs)
- Mount: 5/8 inch female thread
- RF Connector: TNC (straight)


A reflux condenser allows running a reaction at a higher temperature while minimizing the loss of solvent. The reflux condenser is a specially made piece of glassware with a cooling water jacket that condenses solvent vapor, returning it to the reaction flask
This material is prepared using a heated centrifuge in a spin casting head. Before starting material preparation, pre-heat the spin casting head to 60 ~ 65oC.
The first step is preparation of the catalyst solution and reaction solution
Setting up a reflux condenser is relatively simple, with the biggest concerns being stable water supply and leaks at the connections.


Use needlepoint bipolar ionization to make your HVAC systems pandemic ready. Kill pathogens, and reduce particulates, odors, and VOCs.
As facilities reopen, including workspaces and classrooms, Indoor Air Quality (IAQ) becomes more important than ever. Global Plasma Solutions needlepoint bipolar ionization (NPBI) systems work to clean the air inside commercial and residential buildings safely.
Business Wire reports that Global Plasma Solutions is the first air purification solution to test SARS-CoV-2, achieving a 99.4% reduction of the surface strain within 30 minutes.
Clears the air of particles faster
Particulate matter includes pollutants, dust, allergens, mold, bacteria – and viruses. GPS’ technology constantly generates a high concentration of positively and negatively charged ions. These ions travel through the air continuously seeking out and attaching to particles. Larger by virtue of combination, they are more easily captured by the ventilation and filtration systems or become too heavy to remain suspended in the air.
When ions come into contact with pathogens, they steal away hydrogen from the pathogens, reducing the infectivity of the virus.
GPS’ needlepoint bipolar ionization is OZONE free and safe to use across commercial, industrial, and residential buildings. Traditional bipolar ionization systems produce harmful ozone as a byproduct.
- GPS units are installed in air-driven systems (furnaces, air handlers, rooftop units, and ductless mini-split systems).
- They can connect to your building automation system.
- Installed by trained HVAC technicians.
Our professionals can discuss indoor air quality options with you to best fit a solution for your home or business.


New pressure burner
In COMPACT2 we use a brand new overpressure burner, developed specifically for this innovative infrared radiator. Generally speaking, overpressure burners have a very high combustion efficiency but a short flame. With our technical solution, we managed to stretch the flame to an even greater length than the previous model. As a result, the temperatures of the radiation tubes are evenly distributed and there is no overheating in the first two meters behind the burner box.
The gas radiant tube is delivered right from the Lersen production plant in individual segments 2m in length, already completely assembled. Therefore, the assembly itself is very simple: you just need to assemble them together and connect with six screws.
MOM – DAD Dilatation
COMPACT2 uses a unique dilatation system developed at Lersen. It is a system we familiarly call “MOM <-> DAD”. The radiation tubes are equipped with very precisely turned flanges, which are welded to the radiation tube. The “MOM” flange is firmly attached to the segment face and the “DAD” flange is loose. When the radiating tubes start to expand due to the heat, the “DAD” flange slides into the “MOM” flange. The dilatation therefore takes place inside the radiation tubes and does not affect the design of the device. Infrared heaters are therefore not deformed by heat and always remain dimensionally stable.
The electronics in the new COMPACT2 gas radiant tube keep the burner fan running at minimum speed after the heating has been switched off, thus preventing the direction of the draft from rotating. The hot air, heated by the accumulated heat from the radiation tubes, therefore still flows from the burner to the flue and the energy is gradually sent into the hall without uselessly escaping by suction to the exterior. The whole system is controlled by a temperature sensor in the flue gas, so the time for HEATENDING can vary and is determined by the speed at which the residual heat is sent to the hall.
Lersen’s ANTI-CONDENSATION system can effectively prevent condensation in the radiant tubes by not allowing the burner to switch off until the device warms up to operating temperature, helping to extract any condensate, but it has little effect on eliminating condensate in long uninsulated or coaxial flues.