A satellite phone is a mobile phone that connects to satellites rather than the traditional cell phone towers which typical cell phones connect.
Depending on the how the particular service is designed coverage may be a specific area all the way to the entire earth.
Many systems require a direct line of sight to the satellite which requires the user to be outside rather than in a dwelling where the structure will block the signal. Buildings, trees and other obstructions can have an impact on the signal strength and affect the quality of the call.
Satellite phones boldly go where cell phones can't. They let you make phone calls from almost anywhere because their primary infrastructure is literally out of this world. Satellite phones don't rely on a terrestrial cell phone network. Instead, they beam their data directly to and from satellites orbiting Earth.
That technological leap unleashes satellite phones (or sat phones) from the bonds restricting their Earth-based brethren.
Thus, they are the communication devices of choice in areas with minimal or non-existent cell coverage, such as sparsely populated or poor countries, locations where governments restrict cell and Internet access, or where natural disasters wreck ground-based systems.
In satellites systems, phones aren't always referred to as phones. Instead, many people call them terminals. No matter the name, they're the necessary end-user device that you need to connect to a satellite.
How a satellite phone works.
By their very nature, satellite phones adhere to a different set of rules, not just technologically, but politically, too. To that end, governments that prefer to control the communications options of their citizens are not fond of satellite phones.
Satellite phones send radio signals to a satellite which then transmits back down to earth where a station will then route the call to the Public Switched Telephone Network (PSTN).
In some cases the satellite phone provider will transmit from one satellite to another satellite which has a connection to an Earth station. Outbound calls are relayed from the satellite phone on the ground to one of the satellites within the line of sight.
Next the call is relayed from one satellite to another at which it reaches the correct satellite to then connect back down to the appropriate ground station. The call is then transferred to the public voice network or Internet when it reaches the recipient.
As the Arab Spring spread to Syria, which subsequently sank into civil war, the government severed many cell and Internet communications. This forced rebels and activists to use sat phones. In fact, there was such a large spike in demand for sat phones that the region's main service provider, Thuraya, reported shortages of handsets [source: Hamid].
Sat phones aren't vulnerable only to human interruption. They're also subject to the whims of Mother Nature. As with cell phones and other radio-based communications, sat phones may be rendered useless in the face of massive solar flares and other natural phenomena.
Satellite Phones will hurt your bank account.
Compared to their ubiquitous cell phone counterparts, sat phones are a fringe technology. As with so many exceptional devices, they are more costly to use than more pedestrian phones. Prices may vary substantially depending on whether your provider uses geostationary or LEO satellites.
As of 2021, for a better-than-average LEO handset, you can easily drop around ₹111746/$1,500. For a briefcase-sized geosynchronous-compatible phone, you'll blow spend several thousand dollars.
Costs associated with voice calls from a satellite phone will vary anywhere from around $0.15 to $2 per minute, with typical rates being from .80 to 1.50/minute. Some providers will offer better rates within specific geographic areas for even lower rates.
Calling a satellite phone from traditional landlines and normal cell phones is quite more expensive than other normal calls. Satellite calls between different satellite phone networks is often very expensive, with calling rates of up to $15 per minute. Most satellite phone networks offer pre-paid plans, with amounts ranging from $100 to $5,000.
Satellite company operators clearly understand that their services are much more expensive than a typical cell phone plan. That's why they often sell minutes as pre-paid plans. You're less likely to mindlessly run up bankruptcy-inducing bills if you've already spent that money in advance.
Who uses satellite phones?
Typically the types of individuals who use satellite phones are ones with a need to have communication from remote locations.
Although the cost of these phones and services has dropped significantly over the last 10 years and more and more people are finding a need for them, the large numbers of users are associated with Aviation, Emergency services, Government, Maritime, Military.
Satellite phone features..
Just like cellular phones, satellite phones use SIM cards and offer an array of features. These would typically include low battery and signal strength displays, call forwarding, phone books, voicemail, and text messaging. Hand held satellite phones are battery-operated and would usually provide about 4 hours of talk time and 36-40 hours of standby time. Many satellite phones have additional features such as:
GSM compatibility enabling the phone to be used as a cellular phone.
GPS displays of longitude and latitude.
Solar panels for remote recharging of the battery.
Paging, data transmission and faxing capabilities.
Made for rugged environments with water, shock and dust resistance.