This new space communication business will provide
CD quality digital radio to subscribers beginning
in autumn of 2001. In summer of 2008 XM and Sirius
got approval to merge. Eventually, there will be products
taking advantage of this such as radios that can receive
signals from both satellite systems.
In the US the service is aimed primarily for mobile
applications, especially drivers on long commutes
and truck drivers going cross-country.
Worldspace aims at the developing world with digital
radio. It relies on public radio and advertising based
services rather than subscription.
Radio Receivers XM Radio began
offering satellite digital radio in the US in the fall
of 2001. For $10 per month you receive up to 100 crystal
clear stations from anywhere in the US. (Ground transmitters
are used in narrow city streets, tunnels, etc. where
satellite signals cannot reach.) As of June 2003 it
had over 600k subscribers
Note that each radio requires its own subscription.
Some units are movable, like detachable CD players,
that can be moved from an indoor station to a holder
mounted in the car.
In-door radios need to be used near a window or connected
to an outside antenna with a clear view towards the
Radio Receivers Sirius is
the second US based digital satellite radio company
and got off to a slower start due to technical problems.
But it is comming on fast. As of June 2003 had over
Service costs $13 a month. The 60 stations operated
by Sirius service has have no commercials than XM. The
other 40 or so stations are independent of Sirius and
many of these have commercials.
Digital Satellite Radio Receivers
Worldspace was the first to offer digital satellite
radio. It's two satellites currently serve Africa, parts
of Europe, and Asia. A third satellite will be launched
to serve central and south America.
Currently all channels are free. A subscription premium
channel service, however, is in the works.
Receivers are now available from several manufacturers
and prices are starting to dip below $100. The expectation
is that as the market grows, the prices will continue
DTH TV is the biggest success for any satellite
service directly sold to the consumer (as opposed,
for example, to the distribution of TV programming
by satellites to cable TV companies). In the US the
number of subscribers now exceeds 17 million. There
are tens of millions more in around the world.
Initally consumers used large C-band dishes to pick
off analog transmissions intended for cable companies
and other businesses (which people still do, see the
section). Eventually C_band subscriber
services was developed. However, higher frequency
Ku band digital transmissions became available and
were intended specifically for consumer subscribers.
Offering a hundred or more of channels via much smaller
dishes, the systems became very popular and have mostly
supplanted the C-band business.
SkyB in Britain pioneered DTH. In the
US, the Hughes DirecTV and Echostar became the leading
While high-speed internet connections are usually
expected to come over telephone lines (DSL) or via
cable TV systems, satellite delivery is also an alternative.
Rural areas will not have DSL or cable for many years
if ever and even some urban areas will not see DSL
DTH internet via geostationary satellites has become
more broadly available in the past year . The long
distance to GEO causes an additional delay but this
is usually not significant except for interactive
applications such as network games.
Initially, only 1-way downloading from the satellite
was available. A telephone line was also needed for
uploading and sending emails, web page requests, etc.
Now, however, full 2-way systems are available.
low earth orbit internet systems have been
proposed that would eliminate the long delays and
provide higher rates. But most of these have been
canceled or indefinitely delayed due to the recession
in the telecommunications market and the aftereffects
of the Iridium and Globalstar satellite phone company
failures. So in the meantime, the geostationary systems
will be the only option for broadband satellite connections.
(Both Iridium and Globalstar offer low speed internet
The high altitude of the geostationary satellites
results in an unavoidable delays (due to the speed
of light) of about half a second. This means that
gaming and other applications that need fast immediate
response will not work well or at all with geo-broadband.
However, once a connection is made the "flow
rate" of the data coming in or going out is as
fast as most groundbased broadband systems. So for
emailing, downloading files, web surfing, etc., the
slight delay after "clicking" can be insignificant
compared to the usual internet delays.
Note that the satellites currently in use for home
internet were not designed for this sort of mass market.
New satellites with more spot beams and using a higher
frequency band will go into orbit in the coming years
and should provide substantially better service. Also,
ICO is in the process
of building a 12 satellite system in medium earth
orbit, which should greatly reduce the signal delay
The prices for satellite internet are currently higher
than DSL or cable and there can be significant installation
costs. Echostar and DirecTV offer combined TV/internet
systems with a single antenna and subscription billing.
The geo-satellite broadband systems have had a slow
and somewhat rough startup with many customers complaining
of difficult setups, frequent down times, poor support,
etc. The situation seems to be improving but there
are still problems.
Communications -this VSAT
company received investments from EchoStar and Microsoft
for this 2-way broadband internet system that began
in 2000. It has about 40k subscribers as of Spring
2002. EchoStar pulled out of the company to focus
on its merger with DirecTV. This caused major disruption
in its ooperations and it had to go into bankruptcy
to re-organize. However, it appears to be a temporary
condition and service continues.
now offers 2-way service but prices are aimed more
towards small businesses than home use.
(formerly iSky) now has satellites for direct to home
(or small business) 2-way services with download speeds
up to 1.5Mbps - "30x faster than dial-up".
- in addition to their mobile phones, Inmarsat
also offers some attache case sized Internet systems.
Too expensive for home use but good for your sailing
boat or summer house in the mountains.
Phones & Message Pagers
Despite what you may have heard, the personal satellite
phone business is still very much alive.
The original Iridiumcompany went bankrupt but was resurrected as a new
company that concentrates primarily on users at remote
locations, e.g. oil refineries, ships at sea, etc. The
company currently has about 130,000 subscribers.
also reorganized as a much smaller, private company.
It has about 150,000 users.
Two other systems called Inmarsat
Satellite provide phone service via satellites in
geostationary orbit. (So their coverage is somewhat
less than Iridium and Globalstar.)
If you are boater, spend time in the mountains or
in other areas with poor cellular coverage, or just
want to roam the US and the world without dealing with
multiple phone systems, then a satellite phone could
be for you.
These systems also offer emergency communications during,
for example, natural disasters such as tornados and
hurricances when cellular systems will be unavailable.
Here is a list of the major systems currently available
and a sample of retailers.
Globalstar This 48 LEO satellite system does not provide 100%
world coverage but does serve most land areas within
the mid-latitudes. Dual and tri-mode phones automatically
use local, cheaper cellular service when available.
Their satellites have been upgraded and they now offer
reliable phone service after a period when some of their
first-gen satellites were disabled.
Dual mode - digital GMS and Globalstar (CDMA)
Tri-mode - analog cellular (AMPS), digital cellular
(CDMA) and Globalstar (CDMA) modes.
Inmarsat Inmarsat satellite portable phones have been
used for many years by sailors, correspondents and others
who needed communications in remote areas. The phones
come in a briefcase sized package to hold the antenna
needed to reach one of 4 geostationary satellites.
Newer versions are smaller but there is still no handheld
version. Suitable for a boat or remote cabin.
The original Iridium went bankrupt and was sold at a
bargain basement price to a private investment group.
Their business plan is anchored on a contract with the
US defense department. However, the company now also
has a considerable commercial and public customer base
for its phones. They also offer aviation communication
A next-generation of satellites will be launched in
the 2015-2016 time frame
Iridium is still the only system that gives true 100%
world coverage including the oceans and polar regions.
Thuraya uses a GEO satellite to provide coverage that
"spans Europe, North and Central Africa, the Middle
East, the CIS countries and South Asia".
The dual-mode phones offer satellite and GSM connectivity
so roaming will use GSM when available and switch to
satellite otherwise. The phones also offer services:
GPS, data, fax up to 9.6 Kbps and short messaging.
The company works through local mobile service providers
who sell the phones, do the billing, etc.
The Orbcomm system of 35 LEO satellites does not provide
audio connections but instead provides low data rate
messaging. The system is intended for many industrial
applications, such as electrical meter reading and gas
pipe monitoring, but also for personal email communicators.
GPS - Global Positioning
As described in the HobbySpace
GPS section, the GPS system provides
high resolution location finding via a constellation
of 24 satellites that send out signals indicating
their position. If 4 or more of these satellites are
in range of a GPS device, it can triangulate its location.
That section provides many applications,
There are many GPS devices now available to the
consumer. Depending on the design, the devices can
obtain location accuracy anywhere in the world to
within as small a range as 15m (~50ft) .
GPS devices are now available at prices
as low as $100. The low end devices provide basic features
such as current position, distance and direction to
a set point, current speed, trip distances, track logs,
More expensive devices provide map features such as
showing your current location on a map display. Also,
they can guide you to a given address. They also have
bigger, more sensitive antennas for faster, more reliable
Use your GPS for obtaining location as well as distances
travelled while hiking, canoeing, etc.