21/07 - PLEASE NOTE: This article has been left here for legacy
purposes. You can read the updated articles about mobile internet at
our new site: ConnectWirelessWeb.com.
March 19, 2003 - For those of you
with my cellphone article regarding
internet connections, you know that managing an international
web hosting service is not an easy job. It requires constant
attention to server communications, with long days that often run from
5:00 AM to midnight. While traveling, I had been using cellphones for a
number of years to maintain communications, but I found the slow speed
and limited area coverage was hampering my schedule and travel
flexibility. Even in cities in areas of full signal strength, I found
that multipath signal reflections off buildings or nearby hills would
prevent data connections even though the voice transmissions may have
Although I have a high speed satellite internet dish system, I can't take it with me when flying on planes and staying in hotels, and it doesn't solve the voice communications problem if there's no cell service available. Thus, I decided it was time to employ satellite phone technology, with the hopes that it would improve my overall communications capacity. Does it work? Yes, you betcha - almost everywhere, with a few caveats. This is the story of my satphone experience ...
At present, other than specialized commercial/marine systems, there are two main players in this arena: Globalstar and Iridium. Both companies have recently been rescued from bankruptcy because this technology has not caught on with the general public, but I think they will ultimately succeed as the cost comes down (as it already has). I chose Globalstar primarily because of the difference in the way it handles data (more about this below), which is as important to me as voice communications.but if you are going offshore or to the polar regions, Iridium may be a better choice because of the more uniform coverage of the globe.
So I plunked down the money for my 'trimode' Qualcomm GSP 1600 satellite phone and hooked the serial port on my laptop to the phone after installing the CD setup program. One click activated the dial-up icon, another click to connect me (9600 KBps CDMA Packet Data), and presto - I was promptly able to fetch my email ... aaah, I liked it already! (please see further in this article for more operating details)
Although slightly larger than a cellphone, it will still fit into a pocket well enough to be considered truly portable (12 oz). The satellite antenna is longer and thicker than what you might be used to with a regular cellphone, but the telescoping design is cleverly engineered to retract completely into a cavity within the body of the phone (it should always be kept vertical when in use).
The 'trimode' designation refers to the capability of this phone to work as a regular digital (CDMA IS-95) or analog (AMPS IS-41) cellphone, as well as a satellite phone (the smaller antenna on the right hand side of the unit above is for regular cellphone use).
The phone can be configured to seek out the presence of your analog or digital service, and if it doesn't find either (cheap airtime), it will then switch to satellite mode (more expensive airtime). However, I programmed mine to work in 'satellite only' mode because I already have separate analog and digital phones and I didn't want those numbers reprogrammed into my satellite phone because I'd lose the use of my separate cellphones (you can't have the same number programmed into 2 different phones). I also didn't want the phone to waste time seeking out terrestrial cell signals either, as it can take a minute or two to sort it out.One other important point: the Qualcomm satellite phone does not support internet data connections on the cellular side, so I would lose my ability to connect to the net on the cellular system if I used the satellite phone as my cellphone too. If you are interested in voice only, or don't want to use cellphones for data, the trimode feature could prove useful. Since I only use it in satellite mode, this article will not cover the use of this phone in cellphone mode; if you're interested in more information regarding cellphone use, please visit my cellphone article.
I found this phone relatively easy to use (works just like my cell phones) - the menu system is clear and logical, and the unit has very acceptable battery life as per the table below (you use AC and DC chargers just as you would with a cellphone). Qualcomm claims it is currently the "only satellite phone with standard US dialing. Also supports all standard dial tone, dial procedure, and call progress touch-tones."
Talk Time/Standby Time:
CDMA digital (IS-95)
AMPS analog (IS-41)
Globalstar satellite system uses a constellation of 48 Low-Earth
Orbiting (LEO) satellites (or 'birds') to relay signals from over 80% of
the Earth's surface, excepting
the extreme Polar Regions and some mid-ocean regions. The satellites are
placed in eight orbital planes of six satellites each, inclined at 52
degrees to provide service on Earth from 70 degrees North latitude to 70
degrees South latitude, orbiting the earth every 113 minutes. Included
in this array are a number of 'spares' that can be activated in the
event of failure of any of the operational birds.
These are not stationary, geosynchronous satellites such as those used with a precisely aimed satellite dish, which have to be in a unique, high orbit about 23,000 miles above the equator. The lower orbits (about 900 miles up) have an advantage in that there is little or no echo or delay with voice and data communications. Globalstar also claims, although they are in motion relative to the earth's surface, that there are at least 4 birds in view at any given time. It also means that the reduced distance to orbit allows a low power, hand held phone with an omnidirectional antenna to work while in motion (just like a cellphone). In fact, you could think of this as an 900 mile high cell tower ...
The satellites themselves use a 'bent pipe' technology, which keeps them simple, cost effective and reliable. There is minimal signal manipulation occurring on the birds themselves; they act basically as reflectors or mirrors, bringing the signals down to earth station 'gateways' that conduct all the sophisticated digital signal processing. If you move behind an obstacle, or the communicating bird drops below the horizon, your signal is automatically 'handed off' or 'soft-switched' to another satellite in view (with no detectable interruption of service). This is a patented technology referred to as 'path diversity'.
how well does it work? It works quite well, as I found out, as long
as you understand the limitations. The first thing you need to
understand is that it does not work well inside buildings,
behind trees and mountains, or in vehicles (but there is a 'hands free'
car kit option available). The optimum condition is that of an open
area, with no obstructions to the sky.
The second thing you need to understand is that the coverage pattern is not uniform around the globe, it is optimized for the major continental land masses. Thus coastal regions and offshore islands may actually be in fringe areas. This doesn't mean it won't work in these regions, it just means you have to be more careful about obstructions, and you may have to wait for a few minutes for a bird to come into view.
Because the system is optimized for the continental mass, you could think of that 900 mile high cell tower analogy as being somewhere in the center of the continent, perhaps in Kansas. Thus, if you are in Seattle, you should try and get an unobstructed view of the southeastern sky; if you're in San Diego, you should go for an open view of the northeastern sky. You could also extend the cell tower analogy a bit further and think of it not as a tower, but as a giant 900 mile high spinning Ferris wheel with the earth at the center, with transponders spaced on the rim at regular intervals. It is important to understand that the signal conditions on your phone are quite dynamic, and will vary minute to minute as the birds pass through the sky above you, silently handing you off to new ones coming up over the horizon as the current birds drop away from contact.
If you are in a situation where an unobstructed view is not available, it will still work, but you may experience longer signal acquisition seek times when you to turn the phone on, as well as dropped connections during use. Nevertheless, I have used it quite successfully under these conditions to retrieve and send email, including being behind open windows in buildings, in vehicles with open windows, under light tree cover and behind hills. It is not affected by weather conditions or reflections off large buildings (multipath) as cellphones are.
I also found that it worked well in my fiberglass motorhome, if I hung it in the acrylic skylight window - it wasn't necessary to take it outside. When staying in hotels, I have a long serial extension cable which allows me to hang the phone outside a window or put it on a balcony. Keep in mind that sooner or later, a bird will be in view, even in an obstructed location, so sometimes you just have to wait longer to get the signal you need (and do it quickly). If you need to make a long, uninterrupted phone call, you may be better off to wait until you get into the open.
Globalstar system has one very important advantage regarding the
handling of data. Unlike cell phones, you do not need to dial-up to your
own ISP for an internet connection; they provide their own gateway ISP
services, including an outgoing mail server. When the data kit CD is
installed, it sets up a separate dial-up connection icon that connects
you to their own gateway system. As soon as you turn your phone on, you
can click on the 'connect' button and it will establish the connection.
It will also wait and connect you as soon as signal is present if your
birds are temporarily out of view in an obstructed area. There is no
detectable handshaking period as the digital connection is almost
instant, and it stays rock solid as long as the signal is present. The
data rate is 10k, but it seems like a fast 10k because it does not
behave intermittently with the data stream stalling as cell phones often
do (I can see this clearly with my data stream analyzer). Thus, your
actual billed airtime is much less - I was able to retrieve typically 10
to 20 messages in under a minute or two and log off. In that same short
session, I was also able to send out several responses that I had
prepared from a previous login. I also found that it was fast enough to
surf the net if I needed to pull in a website, such as a satellite
weather picture. If you're roaming in another country this could get
expensive, but it's nice to know you can do it if necessary.
I also liked the fact that the voicemail system will notify you with a series of beeps if you have received any messages while the phone is off or signal has been temporarily lost. This saves you from having to keep checking in for messages on your voicemail. If I'm going somewhere where I know my cellphone won't work (eg. Mexico), then I just call-forward my cell to my satphone number, and I can receive calls just as if I was back at the office. If I don't set it up that way, I can still use my Satphone to call my cellphone voicemail for messages.
I traveled from the Pacific Northwest area to San Jose (definitely a 'fringe' area) on the southern tip of the Baja in the winter and used the satphone whenever my cellphones wouldn't work. This gave me almost 100% coverage on my travels, for both phone and internet purposes. Although I chose my locations with some care, I found that I could go almost anywhere I wanted - much more so than with just cellphones only. The airtime cost is higher than cell (although the basic monthly rate is quite reasonable - it's not expensive when you aren't using it), so I use satellite only when I need to, but it sure has improved the quality of my travels. No more hassles with being stuck in a place where I can't get connected, and no more hassles with ISP's and cellphone companies in other countries, especially when I don't speak their language!
In conclusion, it is my opinion that Globalstar is a well thought out, well engineered system that allows me to have voice and data communications just about anywhere I care to go.
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