How Satellite Phones Work When Land Based Communication Fails
In this world where hurricanes and earthquakes are a regular occurrence emergency satellite communication is now a necessity.
Satellite phone communication works very well when you travel outside of landline and cellular communication or if the landline and cellular communication is over loaded or disrupted. When hurricane Katrina hit New Orleans local landline and cellular was disrupted for days.
With satellite commutation you must have the antenna outside ways from large structures and trees to get line-of-site to one of the satellites. Trying to use a handheld satellite phone inside a building does not work very well because you do not have line-of-site to a satellite. Using a hand held satellite phone close to a window may give you service but you may get a high number of dropped calls and periods of no service.
Satellite phone communication works like this, when making a call the signal goes up from the satellite phone handset or fixed site unit to a satellite then that satellite transfers the call to a ground station or gateway. After the ground station receives the call the call is transferred to the public telephone service where it is connected to a landline or cellular phone. If the landline and cellular phone service is over loaded or disrupted that call cannot go through. Keep in mind just because you are using a fully function satellite phone that does not mean you can call a landline or cellular phone that has been disrupted.
The best way to communicate when terrestrial commutation has failed is to create communication groups. Your communication group will need to have the same satellite phone service to fully communicate with each other. The most popular satellite phone providers include Globalstar and Iridium. Your communication group would need to choose the same satellite phone provider.
When you choose Globalstar for your satellite phone provider calls to a landline or cellular phone would go up from the handset to one of the 48 satellites then it is relayed down to one of the Globalstar ground stations where it is transferred by landline to its call destination. If landlines are disrupted and everyone in your communication group are using Globalstar phones calling another Globalstar user in the same range of the gateway used by the originator of the call then that call is transferred back from that gateway to a satellite then back down to the user receiving the call. In this case landlines that could be disrupted are never used. If the call is going to another Globalstar user not in the range of the gateway used by the originator of the call Globalstar will transfer the call to another Globalstar gateway through dedicated T1 lines. This type call would then go up from the second gateway to one of the Globalstar satellites then down to the user receiving the call.
If you choose Iridium for your satellite phone provider calls to a landline or cellular phone would go up from the handset or fixed site unit to one of the 66 Iridium satellites where it is relayed down two of the Iridium ground stations or gateways where it is transferred by landline to its call destination. If landlines are disrupted and everyone in your communication group are using Iridium phones, Iridium to Iridium satellite phone calls are handled totally buy the constellation. The Iridium constellation has intelligence built into the system where if both the user originating the call and the user receiving the call are both in line-of-site of the same Iridium satellite, the call is completely handled by that one satellite. If the satellite phone user receiving the call is not in line of site to the satellite handling the user that originated the call then that call is transfer from Iridium satellite to Iridium satellite then down to the user receiving the call. In both cases the Iridium gateway is never used.
We are seeing natural disasters of biblical proportions. It would be wise for all organizations to be prepared with emergency satellite commutations.