solar fade(n.) Also referred to as sun fade, sun outage or solar outage, a signal degradation phenomenon that affects the transmission of radio signals in satellite communications.
GEO satellites orbit the earth above the equator and rely on microwave signals in the radio frequency spectrum for communications with an earth-bound antenna. The sun also emits large amounts of electromagnetic energy in the microwave portion of the spectrum. Through the majority of the year, the radio frequency energy from the sun does not affect satellite communications. However, during the spring and fall equinoxes the sun is positioned above the earth's equator (in the equatorial plane) and therefore will align itself behind the GEO satellites as they move with the earth's rotation. When the sun is directly behind a satellite the radio signals of the satellite communications are overpowered by the sun's radio frequency energy, creating noise, and the communications are therefore disrupted.
Signal interference only occurs once a day for any satellite and usually lasts less than eight minutes, though many factors, including antenna size and downlink frequency, effect the duration and intensity of the solar fade. The exact date and time of solar fade is different for each satellite. Many satellite operators have solar fade calculators accessible on the Internet.
Stay up to date on the latest developments in Internet terminology with a free weekly newsletter from Webopedia. Join to subscribe now.
Like everything in technology, AI touches on so many other trends, like self-driving cars and automation, and Big Data and the Internet of Things... Read More »DevOp's Role in Application Security
As organizations rush to release new applications, security appears to be getting short shrift. DevSecOps is a new approach that holds promise. Read More »Slideshow: Easy Editorial SEO Tips to Boost Traffic
This slideshow reviews five easy on-page editorial SEO tips to help drive organic search engine traffic, including the page title, heading,... Read More »
Java is a high-level programming language. This guide describes the basics of Java, providing an overview of syntax, variables, data types and... Read More »Java Basics, Part 2
This second Study Guide describes the basics of Java, providing an overview of operators, modifiers and control Structures. Read More »The 7 Layers of the OSI Model
The Open System Interconnection (OSI) model defines a networking framework to implement protocols in seven layers. Use this handy guide to compare... Read More »