Demand
Soars For Satellite DSL, Satellite Tv & DSL Internet Services
...with
satellite dsl being one of today's hottest new technologies!
Welcome To HighSpeedSat!
A one-stop information source for satellite dsl,
satellite phone,
satellite radio, and satellite tv systems, plus voip and dsl
internet service.
Thursday, November 21, 2024
Tuesday, December 7, 2004
Satellite dsl and Satellite Tv are popular choices for today's
consumer. Proof of their tremendous growth lies in a trend that is
literally sweeping across the planet. Have you noticed?...
...satellite dishes are dotting the landscape
everywhere!
In cities, towns and remote locations, mini satellite dishes
point attentively to the Southern sky. Emblazoned with names like DirecTv®,
Dish Network®, and DirecWay®, their numbers are
growing at an amazing rate.
Ever wonder why these satellite dish systems are in such great
demand? Does high speed internet service or digital television
programming via satellite intrigue you?
Great! You're about to learn about some exciting new satellite
technologies especially options for high speed internet access.
These include satellite dsl or broadband service via satellite, as
well as, conventional DSL Internet service from leading providers.
Gaining popularity worldwide, satellite dsl technology is revolutionizing high speed internet access and communications everywhere. It is one of today's hottest commodities because it provides fast, reliable, and secure service most anywhere in the continental US and around the globe.
But, that's not all ....
if audio entertainment excites your senses, take the time to discover why you will love listening to commercial-free satellite radio just about anywhere. It's simply awesome! In fact, you may never want to listen to standard Am/Fm radio again! But ... don't just take my word for it, check it out. Also.... get the latest buzz on Free satellite tv systems - including the features and benefits that make them today's ultimate television viewing experience. Learn how you, yes you!, can experience the best in digital television programming for less than cable tv.
Did you know that satellite phones work just about anywhere? Take a look at the latest wireless telephone solutions available for today's travelers. Now, you can rent or buy a satellite phone or GSM international cell phone at discounted rates to keep in touch with the rest of the world wherever you travel, work or play.
As demand grows for better technology, satellite systems including satellite dsl, radio, television, and telephone, as well as, dsl internet services are delivering innovative solutions. Satellite technology gives you the ability to achieve greater productivity on the internet and to enjoy the best in communication, as well as, television and audio entertainment.
The pages that follow are your keys to understanding the advantages of having satellite technology in your life today. I welcome you to explore them, including our web business resources page.
Learn how you can establish your own business on the Internet with the best web site creation, hosting, and promotion tools available today. Take the time to read this information. It is my belief that you will enjoy and benefit greatly from it!
How Satellite TV Works – A Simple Explanation
Satellite tv is talked about so much in the world of consumer viewing. Satellite dishes, receivers, program packages, PVRs, DVRs, HDTV – what does it all mean? How can you even begin to think of buying a satellite tv system when you’re bombarded with all these meaningless terms? So suppose you really knew exactly how satellite tv works? Wouldn’t that put you in a more positive position? Wouldn’t that allow you to make an informed decision when shopping for a satellite tv system?
There are many pages on the Internet explaining how satellite tv works. Many have a lot of technical information. We’d like to take a simpler approach. So, the following is an explanation of just how satellite tv works – in layman’s terms. Take note – and you can secure some useful knowledge.
The Basics
Satellite tv is a wireless system for delivering tv programming directly to a viewer’s house. It transmits its broadcasts via a radio signal.
The ultimate source of this radio signal is the broadcast stations. They use a powerful antenna to transmit their broadcasts to the viewers. However, these radio signals can travel only in straight lines. So the signal can’t be captured by the viewer on his receiver unless he is in the line of sight of the broadcaster’s signal. Tall buildings, trees, and other such obstructions, can’t block the signal, but it could be blocked by the curvature of the Earth. Therefore, broadcasters needed another medium to transmit their signals to the viewers. Enter satellites.
Satellites were launched. They orbited the Earth at exactly the same speed as the Earth (7,000 mph or 11,000 kph), at a distance of 22,200 miles (35,700 km), thereby creating a geosynchronous orbit, that is, they appeared to be “stationary” above the Earth, “hovering” over a certain point. The result of this geosynchronous orbit is that signals (broadcasts) could be directed from the Earth to the satellites and continually engage them in receiver transmissions.
So now on the ground there was a need for an antenna to receive these broadcasters’ signals. Enter satellite tv systems. These very large satellite dishes started popping up in people’s back yards. Although the satellites took up large areas of the viewer’s property, the programming was very rewarding. The owners of these big satellite dishes could pick up foreign stations, live feeds between broadcast stations, NASA activities and a lot of other programs transmitted using satellites.
Progress brings smaller and more efficient technology
Then direct broadcast satellite (DBS) providers decided to collect the programs available via satellite and re-sell them to the viewer. But the broadcasters (for example, HBO and ESPN) weren’t about to just give away their programs. They charged the DBS providers a fee for these rights. So in essence, the DBS providers are like brokers – they buy programs wholesale and re-sell them for a profit. Two of the most well-known DBS providers are DIRECTV and the Dish Network.
The next challenge for the DBS providers was to create a system more cost-effective and simpler than the large satellite dishes. So they came up with a small satellite dish that viewers could easily attach to their houses or apartments. This opened up a whole new market for their programs.
Program packages were created by selecting certain channels and bundling them, often in a theme – like sports, movies, documentaries, retro, etc. Viewers could choose the package that best fit their viewing preferences, and wouldn’t have to pay for channels they weren’t interested in.
So in review, here’s the basic path of a radio signal containing television programming: the programming source (the broadcaster), to a satellite, to the DBS broadcast center, back to a satellite, to the viewer’s receiver, to the television set.
Exactly how is this signal sent?
Early satellite tv was broadcast in C-band radio (3.4 GigaHertz [GHz] to 7 GHz). Remember, the picture and sound making up the signal is actually a radio signal. But the broadcasters wanted to provide superior video and audio to its viewers, so they started transmitting their programs in the Ku frequency (12 GHz to 14 GHz). Thus was invented High-Definition Television (HDTV). Now the picture and sound were theatre-like in quality. This also gave them a jump on their competition – the cable companies.
Now for a quick, but not too deep, look at the technology of the satellite signal. The original broadcasts are converted into a high-quality, uncompressed digital stream containing a lot of data, and sends it at a speed of 270 megabits per second (Mbps) for each channel. But unless all this data was compressed, the satellite wouldn’t be able to accept it.
The system of compression used in the U.S. is the MPEG-2 compressed video format. This is similar to the system used to make DVDs. The provider could now reduce the 270-Mbps stream to about 5 or 10 Mbps, enabling them to transmit about 200 channels, instead of the 30 they could transmit before compression. The signal was scrambled so only paid subscribers could receive it.
This was the turning point towards the huge success the DBS providers now experience. Again, this put them ahead of the cable companies.
The Receiver – the end and the beginning
The receiver is almost at the end of the signal’s journey, accepting the program signal and converting it into a format that can be viewed on your tv. It’s also the beginning of your viewing pleasure. The receiver does three basic things:
It receives and de-scrambles the signal which contains the program.
It separates the individual channels you request by way of the channel selector button on either your tv or your remote control.
It tracks your pay-per-view usage (the special programs you order), and sends your billing information for this programming to your provider.
Receivers do a few more jobs as well. They display a “TV Guide” (your onscreen programming guide), which comes as part of the signal from the satellite. You can also get special receivers, called Digital Video Recorders (DVRs), which let you pause or record live television.
So now we’ve traced the radio signal from its inception at the broadcaster to its reception on your television. And now you know just how satellite tv works. You’re qualified to make an informed decision when buying a satellite tv system.
Satellite radio is
such a remarkably simple concept that one might wonder why it took until
2001 for the first space-based audio service to make its debut in the
United States.
At least it’s
simple on the surface: Take a music, news or talk station, beam the signal
up to a satellite, and overcome the limitations of ground-based
transmitters whose signals generally drop off as distance increases. Then
make sure the programming is more appealing than traditional radio
stations and cut down on the number of commercials in exchange for a
monthly subscription fee.
But as it turns out,
satellite radio is a whole lot more complex than it seems on paper – and
it took cutting-edge technology to make the systems operated by Sirius
Satellite Radio and XM Satellite Radio work.
XM and Sirius are
not the first companies to enter the satellite radio industry: Worldspace
Corp., a firm based in Washington, has provided satellite radio in Asia,
Africa and Europe since 1998. But Worldspace was intended primarily for use in
One
of XM's two seven-meter uplink satellite dishes located at the
company's headquarters.
fixed locations, while the systems used by XM and Sirius are optimized to
reach U.S. listeners on the go.
Sirius uplinks
its signal from New Jersey, with backup
dishes in Manhattan (above).
It took a number of
years to develop the XM and Sirius systems.
Sirius and XM each
took somewhat different approaches, although the end result, from a lay
person’s perspective, is the same: 100 channels of music, news, sports
and other fare available virtually anywhere in the continental United
States. The companies are trying to distinguish themselves with
programming and attitude.
XM’s system uses
two very powerful satellites floating in space directly above the equator.
The spacecraft are in geostationary orbit -- they appear from the ground
to remain in fixed perches, because they move around the Earth at the same
speed the planet is rotating.
Geostationary
satellites are commonly used for all sorts of space-based communications
because they enable use of inexpensive, fixed antennas. Satellite TV and
Internet systems are two examples of consumer-oriented technologies that
use this type of satellite.
Repeat
that, please
Each XM receiver is
equipped to receive signals from both of the company’s Boeing 702
satellites and a repeater simultaneously. As long as one of the sources is
available, the radio will play without interruption. In addition, the
receivers have buffers that store programming for several seconds,
allowing operation to continue even if no signal is available momentarily.
Sirius uses a trio
of Loral FS1300 satellites in unique elliptical orbits in an effort to
avoid the problems posed by geostationary satellites.
The orbits, shaped
like figure eights, allow the satellites to appear higher in the sky than
XM’s, cutting down on the potential for a listener to be out of range of
a satellite signal -- and allowing Sirius to have a much smaller number of
repeaters.
Sirius’ repeater
network also avoids the need for specialized antennas that can track the
company’s non-geostationary satellites as they move about the sky,
Sirius feeds its repeaters using capacity on a geostationary satellite
leased from a traditional satellite operator. Listeners can’t tell that
the signals they receive via the repeaters do not
travel over Sirius’ fleet of satellites.
The Sirius
satellites each spend about 16 hours over the United States, then whip
around the other side of the Earth and return eight hours later for
another stint hovering over Sirius’ listening area, according to Ted
Hessler, the company’s vice president of space segment and enterprise
operations.
Two Sirius
spacecraft cover the United States at any given time, Hessler said.
In
the studio
Satellite HDTV -The Next Best
Thing To Being There!
Satellite HDTV (high definition television) is today's
"cutting edge" tv technology. Redefining broadcast
television with digitized programming, high definition tv via
satellite delivers imagery and sound that's so lifelike - it's the
next best thing to being there!
What Makes It So Impressive?
Remarkable improvements over conventional analog broadcasts
distinguish high definition television as the system of the future.
The most noticeable difference between hd television and analog tv
is picture quality and size.
This dramatic increase in resolution and aspect ratio (screen width
versus height) produces a "razor sharp" picture
with a significantly wider viewing area.
The excellent picture quality of satellite hdtv is a result of the
best resolution available today. A greater number of resolution
lines produces a sharper, more accurate picture.
In order to have a better appreciation, consider that standard
analog television produces 330 lines of resolution. The much crisper
dvd format provides 400 - 480 lines of resolution. In comparison, DirecTv
satellite hdtv receivers deliver up to 1080 lines of resolution.
Delivering over 1 million pixels on screen, satellite's digitized tv
programming creates crystal clear images with the most minute
details.
A larger aspect ratio allows you to see action on screen that is
normally "cropped-off" with analog broadcasts. The aspect
ratio of hdtv at 16:9 (screen width : height) is more in line with
the human visual field versus the 4:3 ratio of standard analog
television.
Satellite hd broadcasts deliver a home theater viewing
experience that allows you to see movies as they were intended.
Combined with Dolby ® Digital 5.1 Surround Sound, hd programming
via satellite makes you feel as though you are in the midst of the
action on screen.
What Equipment is Needed to Experience
HDTV?
High definition programming from local network affiliates across the
US can be received simply with a high definition tv set and an
off-air hdtv antenna; or, through DirecTv local programming services
where available.
DirecTv® is the first satellite tv service to have its receiving
system built-in to many hdtv sets providing viewers with the added
convenience of easy satellite access.
Participating manufacturers include Hitachi, Mitsubishi, Panasonic,
ProScan, RCA, Samsung, Sony, Toshiba and Zenith. It is anticipated
that additional manufacturers will be partnering with DirecTv® to
provide this service in the future.
In order to experience high definition tv via satellite from DirecTv®,
you will need an HDTV set with a built-in DirecTv® receiver from
any of the above manufacturers; or, a standalone DirecTv®
high-definition receiver and a hd compatible television. You will
also need a multi-satellite tv system from DirecTv® to receive hd
programming via satellite.
DirecTv® delivers high definition programming to its subscribers
via the new, multi-satellite tv system.*
An important component of this system is the 18" x 20"
Triple LNB (low noise block) satellite dish antenna. Why? ...
It allows subscribers to receive signals from three separate DirecTv
satellites simultaneously. Positioned at 101, 110 and 119 degrees
respectively, they deliver all of DirecTv's services including
satellite and local channel high definition programming. (where
available)
*If you have
DirecTv service with the earlier version multi-satellite system
(18" x 24" dish) and you would like to start enjoying hdtv
programs, you will first need to check if your system is hdtv
enabled.
To do so, tune to Channel 99 of your DirecTv HD receiver. If you can
see the DirecTv logo on your screen, then you are good to go.
Otherwise, you will need to upgrade your satellite dish with a Sat-C
self install kit available from DirecTv for a nominal fee. Contact
them directly at 1-800-531-5000 for
details.
Available Programming in HDTV Format
Many ABC, NBC and CBS affiliate stations across the country have
already begun boadcasting in the hd format. In addition, DirecTv
offers a growing lineup of high definition telecasts via satellite
and recently announced its new HD
programming package
Currently, hdtv broadcasts from DirecTv are available on HD Net and
HD Net Movie channels which feature live sporting events like NHL
hockey and Major League Baseball, as well as, movies, concerts and
more.
You can also experience the wonders of nature and space exploration
displayed so vividly on Discovery HD Theater™. Enjoy
magnificent presentations of wildlife and plantlife that looks so
real - you will want to reach out to touch it! Closeups reveal, with
incredible detail, features never before seen with conventional
television.
For sports enthusiasts, ESPN HD captures the action up-close
for virtually every sporting event. Additionally, HBO and Showtime
offer hd broadcasts of championship boxing, big hit movies, award
winning series and Hollywood favorites around the clock. You can
also enjoy high definition programming on select BlockBuster
pay-per-view movie channels.
Satellite Tv Delivers
Pleasure, Excitement & More!
Satellite Tv delivers pleasure and excitement to millions of
families and business patrons everywhere across the country.
Whether it's providing action packed sporting events, up to the
minute worldwide news or classic movie action, DirecTv and Dish
Network satellite television systems are one of today's hottest
commodities!
One of the major reasons for the huge Satellite Tv
demand is outstanding service. Direct tv satellite services
received the coveted #1 ranking for Customer Satisfaction among
satellite/cable subscribers by J.D.Power & Associates for 2002 and 2003!
In a very competitive environment, satellite tv
providers, like DirecTv, have gained national recognition and
approval by using tv satellite dishes and receivers to deliver
quality television programming with personalized service.
Satellite Tv delivers 100% digital programming with cd quality
picture and sound. Quality programming choices with competitve
rates and attentive customer service have made satellite
television a popular choice for many households and business
establishments.
By special arrangement, select on-line dealers are offering
satellite dish systems Free to first time
customers in exchange for a one year service commitment. Learn
about the complete offer requirements for Free Satellite
Tv to see if you qualify.
The following discussion addresses many of the frequently asked
questions about Satellite Tv service. If you have a question not
answered here, please contact us via the link at the bottom of
this page.
Satellite Tv FAQ
Satellite Tv FAQ - Answers:
What is satellite
radio?
Satellite radio is a subscription radio service. It's
similar to cable television, in that it provides a wide range of
programming not available on traditional AM/FM radio for a monthly
fee. back to top
What do I get with a free Satellite Tv
system?
Whether you sign up for Free DirecTv or Free Dish Network offers,
you will receive all the necessary equipment, including a tv
satellite dish, receiver(s), access card(s), remote control(s) and
required cabling with standard professional installation for free.
Satellite tv providers also offer multi-room system packages that
provide all the equipment for multiple tv hook ups for free.
However, in order to get a free satellite tv system, you must be a
first-time customer.
Can I get local channels with Satellite Tv
systems?
Yes! You can now subscribe to local channels in most metropolitan
areas across the country when you order your programming from the
Dish Network or DirecTv. You also have the option of receiving
local channels with an off air antenna that can be connected to
your satellite receiver and accessed via your remote control..
Does the weather affect the operation of
Satellite Tv?
Not usually. On rare occasions, in periods of heavy sustained
rainfall, you may experience a brief period of "picture
freeze" while the receiver re-locates a lost satellite
signal. Signal strength is optimized during professional
installation to reduce the likelihood of signal loss during severe
weather.
Can Satellite Tv deliver international
programming?
Yes! DishNetwork is the leader in providing international
programming offering over six foreign language packages and
several individual foreign language channels as well. See our Free
Dish Network page for more information. DirecTv also
offers programming in Spanish, as well, as Chinese.
Can I watch two different programs on more
than one TV in my house?
Yes, however you need separate satellite receivers to accomplish
this. The dual-LNB satellite system or the new multi-satellite tv
system from DirecTv allow you to use additional receivers so
members of your household can watch different channels in
different rooms at the same time.
What is the DirecTv Multi Satellite System?
The DirecTv Multi-Satellite System allows you to receive signals
from 3 different DirecTv satellites simultaneously. It features
the new Triple LNB (low noise block) satellite dish antenna.
This 18"x20" oval dish gives you multi-room receiving
capability of all of DirecTv's programming and services including
local channel, Interactive, HDTV, foreign programming and Ultimate
Tv. Separate specific receiver equipment is required for HDTV and
Ultimate Tv broadcasts.
What is DirecTv Ultimate Tv?
It's the first and only direct broadcast satellite (DBS)
television platform that integrates all these features in one
receiver: DirecTv® programming, digital video recording, live TV
controls and interactive television, including Internet access
from your TV.
What is a Dish 500 Satellite Tv system?
It's Dish Network's counterpart to the DirecTv Multi Satellite
system. The Dish 500 antenna is an 18" x 20" dual LNB
oval satellite dish that gives Dish Network subscribers multi-room
receiving capability of up to 500 channel broadcasts (currently
256 channels are available). Current broadcasting includes
international, local, Interactive, high definition and Internet
access. Separate specific receiver equipment is required for HDTV,
Interactive and Internet access.
Are DirecTv and Dish Network Satellite Tv
dish systems compatible?
No, you cannot use DirecTv equipment to receive Dish Network
programming or vice versa. Each system is designed to operate
exclusively with proprietary satellites hovering above the Earth
in geo-stationary orbit. The satellites for these systems are in
completely different locations, and their signals can not be
decoded by competitor receiver units.
I live in an apartment. Can I get a
satellite dish system?
Yes! Many apartment residents install the dish inconspicuously on
a south-facing balcony. If your apartment management has concerns
about this, visit the FCC
web site for information on a rule from the Federal
Communications Commission about satellite dish installation on
rental and other properties.
I live outside the US. Can I take advantage
of one of the Satellite Tv offers listed on this site?
Unfortunately, No. All of the Satellite Tv offers listed on this
site are for first-time customers residing in the US only.
Where can I learn more about offers for
Satellite Tv service?
There currently are some excellent offers available for Free
Satellite Tv systems from select dealers for DirecTV and Dish
Network. See our respective pages for Free
DirecTv and Free
Dish Network for more detailed information.
Can I get High Speed Satellite Internet
Access?
Yes!, High speed satellite internet, also known as satellite dsl,
is available in most areas of the continental US and Hawaii. You
can also receive combined DirecTv satellite tv and Direcway
satellite internet service on one DirecDuo dish. See our Satellite
DSL page for details.
DSL internet service is also available from America's leading dsl
providers subject to availability. Check DSL service availability
for your telephone line instantly and get more information from
our DSL
Internet page. back to top
Table
of Contents
Photo courtesy DirecTV
When satellite television first hit the market, home dishes
were expensive metal units that took up a huge chunk of yard
space. In these early years, only the most die-hard TV
fans would go through all the hassle and expense of putting
in their own dish. Satellite TV was a lot more difficult
than broadcast and cable
TV.
Today, you see compact satellite dishes perched on
rooftops all over the United States. Drive through rural
areas beyond the reach of the cable companies and you'll
find dishes on just about every house. The major satellite
television companies are bringing in more customers every
day with the lure of movies, sporting events and news from
around the world.
In this article, we'll find out what satellite television
is all about, from TV station to TV set.
The Broadcast TV Problem
Photo courtesy DirecTV
Conceptually, satellite television is a lot like broadcast
television. It's a wireless system for delivering television
programming directly to a viewer's house. Both broadcast
television and satellite stations transmit programming via a radio
signal (see How
Radio Works for information about radio broadcasting).
Broadcast stations use a powerful antenna to transmit radio
waves to the surrounding area. Viewers can pick up the signal with
a much smaller antenna. The main limitation of broadcast
television is range. The radio signals used to broadcast
television shoot out from the broadcast antenna in a straight
line. In order to receive these signals, you have to be in the
direct "line of sight" of the antenna. Small
obstacles like trees or small buildings aren't a problem; but a
big obstacle, such as the Earth, will reflect these radio waves.
If the Earth were perfectly flat, you could pick up broadcast
television thousands of miles from the source. But because the
planet is curved, it eventually breaks the signal's line of site.
The other problem with broadcast television is that the signal is
often distorted even in the viewing area. To get a
perfectly clear signal like you find on cable, you have to be
pretty close to the broadcast antenna without too many obstacles
in the way.
The Satellite TV Solution
Satellite television solves the problems of range and distortion
by transmitting broadcast signals from satellites
orbiting the Earth. Since satellites are high in the sky, there
are a lot more customers in the line of site. Satellite television
systems transmit and receive radio signals using specialized
antennas called satellite dishes.
Satellites are higher in the sky than
TV antennas, so they have a much larger "line of
sight" range.
The television satellites are all in geosynchronous orbit,
meaning that they stay in one place in the sky relative to the
Earth. Each satellite is launched into space at about 7,000 mph
(11,000 kph), reaching approximately 22,200 miles (35,700 km)
above the Earth. At this speed and altitude, the satellite will
revolve around the planet once every 24 hours -- the same period
of time it takes the Earth to make one full rotation. In other
words, the satellite keeps pace with our moving planet exactly.
This way, you only have to direct the dish at the satellite once,
and from then on it picks up the signal without adjustment, at
least when everything works right. (See How
Satellites Work for more information on satellite orbits.)
At the core, this is all there is to satellite television. But
as we'll see in the next section, there are several important
steps between the original programming source and your television.
The Overall System
Early satellite TV viewers were explorers of sorts. They used
their expensive dishes to discover unique programming that wasn't
necessarily intended for mass audiences. The dish and receiving
equipment gave viewers the tools to pick up foreign stations, live
feeds between different broadcast stations, NASA activities and a
lot of other stuff transmitted using satellites.
Some satellite owners still seek out this sort of programming
on their own, but today, most satellite TV customers get their
programming through a direct broadcast satellite (DBS)
provider, such as DirecTV or the Dish Network. The provider
selects programs and broadcasts them to subscribers as a set
package. Basically, the provider's goal is to bring dozens or even
hundreds of channels to your television in a form that
approximates the competition, cable TV. Unlike earlier
programming, the provider's broadcast is completely digital,
which means it has much better picture and sound quality (see How
Digital Television Works for details). Early satellite
television was broadcast in C-band radio -- radio in the
3.4-gigahertz (GHz) to 7-GHz frequency range. Digital broadcast
satellite transmits programming in the Ku frequency range
(12 GHz to 14 GHz ).
There are five major components involved in a direct to home
(DTH) satellite system: the programming source, the broadcast
center, the satellite, the satellite dish and the receiver. On the
next page, we'll look at each component in more detail.
The Components
Programming sources are simply the channels that
provide programming for broadcast. The provider doesn't create
original programming itself; it pays other companies (HBO, for
example, or ESPN) for the right to broadcast their content via
satellite. In this way, the provider is kind of like a broker
between you and the actual programming sources. (Cable
television companies work on the same principle.)
The broadcast center is the central hub of the
system. At the broadcast center, the television provider
receives signals from various programming sources and beams a
broadcast signal to satellites in geostationary orbit.
The Programming
Satellite TV providers get programming from two major sources:
national turnaround channels (such as HBO, ESPN and
CNN) and various local channels (the NBC, CBS, ABC, PBS
and Fox affiliates in a particular area). Most of the
turnaround channels also provide programming for cable
television, and the local channels typically broadcast their
programming over the airwaves.
Turnaround channels usually have a distribution center that
beams their programming to a geostationary satellite. The
broadcast center uses large satellite dishes to pick up these
analog and digital signals from several sources.
Most local stations don't transmit their programming to
satellites, so the provider has to get it another way. If the
provider includes local programming in a particular area, it
will have a small local facility consisting of a few racks of
communications equipment. The equipment receives local signals
directly from the broadcaster through fiber-optic
cable or an antenna and then transmits them to the central
broadcast center.
The broadcast center converts all of this programming into
a high-quality, uncompressed digital stream. At this point,
the stream contains a vast quantity of data -- about 270
megabits per second (Mbps) for each channel. In order to
transmit the signal from there, the broadcast center has to compress
it. Otherwise, it would be too big for the satellite to
handle. In the next section, we'll find out how the signal is
compressed.
Compression
The two major providers in the United States use the MPEG-2
compressed video format -- the same format used to store
movies on DVDs.
With MPEG-2 compression, the provider can reduce the 270-Mbps
stream to about 5 or 10 Mbps (depending on the type of
programming). This is the crucial step that has made DBS
service a success. With digital compression, a typical
satellite can transmit about 200 channels. Without digital
compression, it can transmit about 30 channels.
At the broadcast center, the high-quality digital stream of
video goes through an MPEG-2 encoder, which converts the
programming to MPEG-2 video of the correct size and format for
the satellite receiver in your house.
The MPEG encoder analyzes each frame and decides how to
encode it. The encoder eliminates redundant or irrelevant
data, and extrapolates information from other frames to reduce
the overall size of the file. Each frame can be encoded in one
of three ways:
As an intraframe - An intraframe contains the
complete image data for that frame. This method of
encoding provides the least compression.
As a predicted frame - A predicted frame contains
just enough information to tell the satellite receiver how
to display the frame based on the most recently displayed
intraframe or predicted frame. This means that the frame
contains only the data that relates to how the picture has
changed from the previous frame.
As a bidirectional frame - To display a
bidirectional frame, the receiver must have the
information from the surrounding intraframe or predicted
frames. Using data from the closest surrounding frames,
the receiver interpolates the position and color of
each pixel.
This process occasionally produces "artifacts"
-- little glitches in the video image -- but for the most
part, it creates a clear, vivid picture.
The rate of compression depends on the nature of the
programming. If the encoder is converting a newscast, it can
use a lot more predicted frames because most of the scene
stays the same from one frame to the next. In other sorts of
programming, such as action movies and music videos, things
change very quickly from one frame to the next, so the encoder
has to create more intraframes. As a result, something like a
newscast generally compresses to a much smaller size than
something like an action movie.
Encryption and Transmission
After the video is compressed, the provider needs to encrypt
it in order to keep people from accessing it for free.
Encryption scrambles the digital data in such a way that it
can only be decrypted (converted back into usable data) if the
receiver has the correct decryption algorithm and security
keys. (See How
Encryption Works for more information.)
Once the signal is compressed and encrypted, the broadcast
center beams it directly to one of its satellites. The
satellite picks up the signal with an onboard dish, amplifies
the signal and uses a another dish to beam the signal back to
Earth, where viewers can pick it up.
In the next section, we'll see what happens when the signal
reaches a viewer's house.
The satellites receive the signals from the broadcast
station and rebroadcast them to the ground.
The viewer's dish picks up the signal from the
satellite (or multiple satellites in the same part of the sky)
and passes it on to the receiver in the viewer's house.
The receiver processes the signal and passes it on to
a standard television.
In the next few sections, we'll look at each step in the
process in greater detail.
The Dish
A satellite dish is just a special kind of antenna designed to
focus on a specific broadcast source. The standard dish consists
of a parabolic (bowl-shaped) surface and a central feed
horn. To transmit a signal, a controller sends it through the
horn, and the dish focuses the signal into a relatively narrow
beam.
The curved dish reflects energy from
the feed horn, generating a narrow beam.
The dish on the receiving end can't transmit information; it
can only receive it. The receiving dish works in the exact
opposite way of the transmitter. When a beam hits the curved dish,
the parabola shape reflects the radio signal inward onto a
particular point, just like a concave mirror focuses light onto a particular point.
The curved dish focuses incoming radio
waves onto the feed horn.
In this case, the point is the dish's feed horn, which passes
the signal onto the receiving equipment. In an ideal setup, there
aren't any major obstacles between the satellite and the dish, so
the dish receives a clear signal.
In some systems, the dish needs to pick up signals from two or
more satellites at the same time. The satellites may be close
enough together that a regular dish with a single horn can pick up
signals from both. This compromises quality somewhat, because the
dish isn't aimed directly at one or more of the satellites. A new
dish design uses two or more horns to pick up different satellite
signals. As the beams from different satellites hit the curved
dish, they reflect at different angles so that one beam hits one
of the horns and another beam hits a different horn.
The central element in the feed horn is the low noise
blockdown converter, or LNB. The LNB amplifies the
radio signal bouncing off the dish and filters out the noise
(radio signals not carrying programming). The LNB passes the
amplified, filtered signal to the satellite receiver inside the
viewer's house.
The Receiver
The end component in the entire satellite TV system is the receiver.
The receiver has four essential jobs:
It de-scrambles the encrypted signal. In order to unlock the
signal, the receiver needs the proper decoder chip for that
programming package. The provider can communicate with the
chip, via the satellite signal, to make necessary adjustments
to its decoding programs. The provider may occasionally send
signals that disrupt illegal de-scramblers, as an electronic
counter measure (ECM) against illegal users.
It takes the digital MPEG-2 signal and converts it into an
analog format that a standard television can recognize. In the
United States, receivers convert the digital signal to the
analog NTSC format. Some dish and receiver setups can also
output an HDTV
signal.
It extracts the individual channels from the larger
satellite signal. When you change the channel on the receiver,
it sends just the signal for that channel to your TV. Since
the receiver spits out only one channel at a time, you can't
tape one program and watch another. You also can't watch two
different programs on two TVs hooked up to the same receiver.
In order to do these things, which are standard on
conventional cable, you need to buy an additional receiver.
It keeps track of pay-per-view programs and periodically
phones a computer at the provider's headquarters to
communicate billing information.
Receivers have a number of other features as well. They pick up
a programming schedule signal from the provider and present this
information in an onscreen programming guide. Many receivers have
parental lock-out options, and some have built-in digital
video recorders (DVRs), which let you pause live television or
record it on a hard drive.
While digital broadcast satellite service is still lacking some
of the basic features of conventional cable (the ability to easily
split signals between different TVs and VCRs,
for example), its high-quality picture, varied programming
selection and extended service areas make it a good alternative
for some. With the rise of digital cable, which also has
improved picture quality and extended channel selection, the TV
war is really heating up. Just about anything could happen in the
next 10 years as all of these television providers battle it out.
For much more information on satellite television and other
broadcast systems, check out the links on the next page.
How Does DIRECTV Technology Work?
DIRECTV first launched its service in the summer of 1994.
According to industry statistics, the DIRECTV® System
became one of the fastest selling consumer electronics product
ever to enter the market — faster than color TVs, CD players and
VCRs.
The DIRECTV System includes a small satellite dish (which is an
antenna for receiving a satellite broadcast signal); a digital
integrated receiver/decoder (IRD), which separates each channel,
and decompresses and translates the digital signal so a television
can show it; and a remote control.
DIRECTV® programming is distributed by six high-power
satellites: four built by Hughes Electronics Corp. (DBS-1, DBS-2,
DIRECTV 1-R, and D4-S), and two built by LORAL (DIRECTV 5, 6).
Each satellite has multiple transponders that relay the DIRECTV
signal from the broadcast centers to home satellite dishes. The
D4-S satellite is a "spot beam" satellite which allows
signals to target specific areas within the U.S., and is used by
DIRECTV to deliver local programming. The "spot beam"
satellite has five antennas and multiple feeds. Each feed projects
its particular signal onto a special location on one of the
antennas. The antenna is specifically shaped to bounce the signal
to a specific location in the continental U.S.
All DIRECTV satellites are located in geosynchronous orbit 22,300
miles above the earth. DIRECTV provides service from three orbital
locations under authority granted by the Federal Communications
Commission (FCC). After the DIRECTV System is installed — a
process that includes aiming the dish at the satellites — no
adjustment is necessary to change programming because the
satellites remain in the same location in the sky. The dish never
has to track the satellites, so there's no waiting for the picture
to come in and little maintenance required.
To gather programming content, ensure its digital quality, and
transmit the signal up to the satellites, DIRECTV created two of
the most sophisticated digital broadcast centers in the world —
in Castle Rock, Colorado, and Los Angeles, California. Programming
comes to the broadcast center from our content providers (CNN,
ESPN, etc.) via satellite, fiber optic cable and/or special
digital tape. Most satellite-delivered programming is immediately
digitized, encrypted and uplinked to the orbiting satellites. Some
programs are copied to professional video servers by the broadcast
centers' state-of-the-art automation equipment to be broadcast
later.
The satellites retransmit the signal back down to each customer's
DIRECTV satellite dish. Before any recorded programs are viewed by
customers, technicians use sophisticated post-production equipment
to view and analyze each tape to ensure audio and video quality.
Professional video layout servers have playback of a program
triggered by a computerized signal sent from the broadcast
automation system. Back-up video playout servers ensure
uninterrupted transmission at all times.
If you're familiar with multimedia computers, you may have heard
of MPEG, which stands for Moving Pictures Experts Group. MPEG is a
technology that can compress a moving image so it takes a tiny
fraction of the space it normally would for transmission.
Uncompressed digital images can be enormous; about ten or twenty
seconds would fill up the hard drive on a home computer. Even
compressed, digital moving images are very large.
Consider this comparison: Your telephone modem can transmit
information at up to 56 thousand bits per second. At DIRECTV, each
of our transponders on the DIRECTV 1-R and DBS-2 satellites can
send about 30 million bits of information per second to a DIRECTV
System, or more than 500 times what a normal PC modem can handle.
This data transmission rate enables DIRECTV to retransmit detailed
moving digital video signals to subscribers. DIRECTV programming
and all DIRECTV Receivers employ MPEG-2 technology, the emerging
world standard for digital broadcasts.