Instabriefs

November 30, 2006

Satellite Communication - Helpful Tips

For either geosynchronous or low earth satellites, the power put out by the satellite transmitter is really tiny compared to that of a terrestrial radio station. Your favorite rock station probably boasts of having many kilowatts of power. By contrast, a 200 watt transmitter would be very strong for a satellite.

The satellite must generate all of its own power. For a communications satellite, that power usually is generated by large solar panels covered with solars cells.These convert sunlight into electricity.

Satellites must also be prepared for those periods when the sun is not visible, usually because the earth is passing between the satellite and the sun. This requires that the satellite have batteries on board which can supply the required power for the necessary time and then recharge by the time of the next period of eclipse.

Links:
www.beginnersguide.com
www.sulu.lerc.nasa.gov

Posted on November 30, 2006 2:42 AM | Permalink

Satellite Internet - Overview

Getting high-speed Internet service by satellite is a great option for many. If you want to know if it’s a good option for you, check out the following facts and tips.

Posted on November 30, 2006 2:43 AM | Permalink

Satellite Internet - Fast Facts

Satellite internet access is ideal for rural Internet users who don’t have access to DSL or cable.

If you have access to DLS or cable Internet, you should use them since satellite internet service will not provide faster services and is about twice as expensive.

A satellite installation can be used even when the most basic utilities are lacking, provided there is a generator or battery power supply that can produce enough electricity to run a desktop computer system.

Satellite Internet does not use telephone lines or cable systems, but uses a satellite dish for two-way (upload and download) data communications.

Upload speed is about one-tenth of the 500 kbps download speed.

Cable and DSL have higher download speeds, but satellite systems are about 10 times faster than a normal modem.

Some firms that offer two-way Internet include: StarBand, Pegasus Express, Teledisic, and Tachyon.

Two-way satellite Internet consists of: a two- by three-foot dish, two modems (uplink and downlink), and coaxial cables between the dish and modem.

You must have a clear view to the south since the orbiting satellites are over the equator. Like satellite TV, trees and heavy rain can affect reception of signals.

Two-way satellite Internet uses Internet Protocol (IP) multicasting technology, which means that up to 5,000 channels of communication can simultaneously be served by a single satellite.

Satellite connection is good for Web browsing and downloading files. Because of long latency, interactive applications such as online gaming are not compatible with satellite networks.

In a two-way geostationary-satellite Internet connection, a transaction requires two round trips between the earth’s surface and transponders orbiting 22,300 miles above the equator.

Satellite systems are prone to rain fade (degradation during heavy precipitation) and occasional brief periods of solar interference in mid-March and late September when the sun lines up with the satellite for a few minutes each day.

Posted on November 30, 2006 2:44 AM | Permalink

Satellite Internet - Helpful Tips

Find out what equipment is provided by the Internet service provider and what equipment you will have to purchase. Some companies can charge a significant amount for the initial equipment you will need.

Find out how fast and reliable the company’s service is. Ask about download speeds and upload speeds. Also check on their reliability percentage record to get an idea of how consistent you can expect their service to be.

Find out if you can connect more than one computer at a time to their service. Will it require that you set up a wireless network?

Find out what the contract period is. Are there any penalty fees if you cancel service before the contract expires?

Ask about technical support. Find out how often it is available and what kind of support it is. Is it provided over the phone or only online?
Links:
www.beginnersguide.com
www.peaceteambook.org
www.searchnetworking.com
www.high-speed-internet-access-guide.com
www.howstuffworks.com

Posted on November 30, 2006 2:45 AM | Permalink

Satellite Television - Overview

Satellite television is commonplace nowadays. If you are thinking of buying a satellite TV system, you might want to know a little about how it all works and get some tips before you purchase your system.

Posted on November 30, 2006 2:46 AM | Permalink

Satellite Television - Fast Facts

Satellite television is a wireless system for delivering television programming directly to a viewer’s house.

Satellite stations transmit programming via a radio signal.

Satellite television systems transmit and receive radio signals using specialized antennas called satellite dishes.

Television satellites are all in geosynchronous orbit, meaning that they stay in one place in the sky relative to the Earth.

Satellites are launched into space at about 7,000 mph, reaching approximately 22,000 miles above the Earth.

Satellites revolve around the planet once every 24 hours – the same time it takes the Earth to make one full rotation.

Most satellite TV customers get their programming through a direct broadcast satellite (DBS) provider, such as DirecTV or the Dish Network.

Providers select programs and broadcast them to subscribers as a set package. DBS providers are like brokers – they buy programming available via satellite wholesale and re-sell them to the customer.

The provider’s goal is to bring dozens or even hundreds of channels to your television in a form that approximates the competition, which is cable TV.

The broadcast is completely digital, which means it has much better picture and sound quality.

Early satellite TV was broadcast in C-band radio, which was in the 3.4- to 7-GHz range. Digital broadcast satellite transmits programming in the Ku frequency range, which is 12 to 14 GHz.

There are five main components involved in the direct to home (DTH) satellite system: the programming source, the broadcast center, the satellite, the satellite dish, and the receiver.

Earlier satellite dishes were large and expensive. Now satellite dishes are small and can be easily attached to homes and apartments.

Your receiver accepts the program signal and converts it into a format that can be viewed on your TV. You can also get a special receiver, called a Digital Video Recorder (DVR), which lets you pause or record live television.

Posted on November 30, 2006 2:47 AM | Permalink

Satellite Television - Helpful Tips

When choosing a satellite TV provider, check out the channel packages each provider offers. Decide what combination of TV channels, movies, and sports is best for your household.

Ask satellite companies if they carry your local channels. Competing satellite providers do not necessarily provide locals channels in the same markets.

Keep in mind that satellite TV generally has better broadcast quality than cable, but is more prone to interference from heavy snow or rain. Also satellite service requires a south-facing surface on which to mount the dish.

Ask if high-definition (HD) programming is available, particularly if you have an HDTV, and what it costs.

Check installation and per-room charges.

Inquire about package deals. Satellite companies usually have packages with digital video recorder (DVR) companies.

The two major satellite TV providers in the U.S. use incompatible equipment. If you change providers, you will need to change the dish and box.

Links:
www.beginnersguide.com
www.howitworks.net
www.howstuffworks.com
www.ehow.com

Posted on November 30, 2006 2:48 AM | Permalink

WiFi - Overview

Do you want the ability to have high-speed connection to the internet that is purely wireless, is fairly priced, or even free? Then WiFi is the way to go. Check out these facts and tips to find out more about how WiFi works and how you can get it.

Posted on November 30, 2006 2:48 AM | Permalink

WiFi - Fast Facts

Wireless-fidelity or WiFi is high-speed access to your computer network and the Internet all without wires.

Radio signals are transmitted from antennas and routers and are picked up by WiFi receivers such as computers and cell phones that are equipped with WiFi cards.

When a computer receives any of the signals within the range of a WiFi network (which is usually 300 to 500 feet for antennas and 100 to 150 feet for routers), the WiFi card will read the signals and create an internet connection between the user and the network without the use of a cord.

Think of the WiFi card as being an invisible cord that connects your computer to the antenna for a direct connection to the internet.

Many new laptops come with a WiFi card built in and in many cases you don’t have to do anything to start WiFi.

WiFi cards can be internal or external, meaning that if a WiFi card is not installed on your computer, you may purchase a USB antenna attachment and have it externally connected to your USB port or have an antenna-equipped expansion card intstalled directly to the computer.

Once a connection is established between the user and the network, the user will be prompted with a login screen and password if it is a fee-based type network. There are also many free-based network connections as well.

WiFi networking around the world is creating hotspots in cities where anyone with a laptop can wirelessly plug into the internet. A WiFi hotspot is a public area such as an airport, café, hotel, store, gas station, office building, etc., where visitors can get wireless access to the Internet via a WiFi access point.

Posted on November 30, 2006 2:49 AM | Permalink

WiFi - Helpful Tips

To connect via WiFi, you need a WiFi enabled laptop or PDA running Windows 98 and above for PCs or OS 8.2 and above for Macs.

Most laptops and PDAs can be purchased from major equipment manufacturers such as Dell, HP, Toshiba, Apple, and others with WiFi preinstalled.

You can determine if WiFi is installed on your computer by checking with your retailer or manufacturer.

If your laptop is not WiFi enabled, you can simply enable your device using a WiFi card that simply plugs into your computer. Most WiFi cards cost less than $100.

Various WiFi card brands are available at both retail computer stores and online. You can also purchase WiFi cards directly from some manufacturers.

There are several hundred WiFi providers to choose from. Most of them have roaming agreements with each other that allow you access to a much larger base of WiFi hotspots. There are also WiFi hotspot aggregators such as Boingo Wireless, Airpath, and Trustive, which allow you to roam on multiple WiFi networks via one service provider.
Links:
www.beginnersguide.com
www.wifi411.com
www.uweb.uscb.edu

Posted on November 30, 2006 2:50 AM | Permalink