21-02-2011, 03:39 PM
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ADVANCED COMMUNICATION TRENDS
SATELLITE PHONES
ABSTRACT
As businesses become more transportable and business men and women travel around the globe, using a digital cell phone service simply isn’t adequate. Many times people have to travel to remote areas or places where service is simply not available for their cell phone. The service systems which don’t run into this problem and can always count on having communication service any where at all time is providence.
After 9/11 one can realize how a stringent activity can turn the world upside down and leave us with the feeling of how vulnerable we can be. When the twin towers were hit the landline and cellular systems in New York where overloaded or disrupted. People in New York had a difficult time calling out to family and friends to let them know they where OK. People calling into New York had problems getting through because most of the circuits where busy. After this terrible act of terrorism numerous government agencies realize it was necessary to have emergency back up communications in the form, which do not rely on local phone systems.
INTRODUCTION:
Communication is defined as exchange of thoughts, messages, or information, as by speech, signals, writing, or behavior.
Types of communication systems:
Communication systems are broadly classified as
• Wired
• Wireless
An advanced wireless communication system includes the following types;
• Satellite communication
• Mobile communication
And now narrowing down to satellite communication:
• Satellite phone
• Global positioning system
SATELLITE PHONE:
A telephone that transmits and receives from satellites that provides coverage around the world. Over eighty percent of the land on earth plus any body of water (we're talking oceans here) is without sufficient landline connection, depending on the architecture of a particular system, coverage may include the entire Earth, or only specific regions. With a satellite phone we are able to communicate with anyone with a phone number from almost anywhere. The sat phone more closely resembles our portable home phone or one of those clunky cell phones from fifteen years ago.
“Iridium was the first satellite phone company”.
An actual satellite phone can also be referred to by professionals in the satellite service field as a terminal or ‘earth station’. Some satellite phones can be chunky and reminiscent of the type of cell phones that were used in the 1980’s, but not all are made that way. Satellite phone shapes and sizes are changing much in the same way that digital phones have over the past decade. These are popular on expeditions into remote areas where terrestrial cellular service is unavailable.
A fixed installation, such as used shipboard, may include large, rugged, 9rack-mounted electronics, and a steer able microwave antenna on the mast that automatically tracks the overhead satellites.
The Need for Satellite Phone Systems
There are only two ways to hook up two telephones in different parts of the world: they can be connected by a cable which runs on the surface of the earth and under the sea, or they can be connected by radio. Not every place on the earth is served by a cable connection to the Public Switched Telephone Network (PSTN), and thus some locations must either have no telephone service or be connected to the PSTN by a radio link.
Modern cellular phones in the industrial countries mostly work in the cities and on the major highways. This is because each cell is a radio page link from the cell phone to the PSTN; and if a cell phone user is located where there are no cells, there is no service.
Because the earth is round, and because most radio waves travel in straight lines, it is not possible to form a direct radio page link to a telephone or a gateway to the PSTN which is located over the horizon. An exception to this rule are the low frequency bands which can follow the curvature of the earth, but these frequencies were all allocated for other purposes decades ago and are not generally available for telephone service. Also it is possible to have a line of radio relay stations that stretch along the earth, but these are only practical for a large number of circuits carried by the PSTN. They play a similar role to the surface cables of the PSTN and are not generally available to individual subscribers.
Almost all of the world-wide telephone voice traffic is currently carried by surface and under-sea cables. This has now changed because satellite phones have now become operational.
ADVANCED COMMUNICATION TRENDS
SATELLITE PHONES
ABSTRACT
As businesses become more transportable and business men and women travel around the globe, using a digital cell phone service simply isn’t adequate. Many times people have to travel to remote areas or places where service is simply not available for their cell phone. The service systems which don’t run into this problem and can always count on having communication service any where at all time is providence.
After 9/11 one can realize how a stringent activity can turn the world upside down and leave us with the feeling of how vulnerable we can be. When the twin towers were hit the landline and cellular systems in New York where overloaded or disrupted. People in New York had a difficult time calling out to family and friends to let them know they where OK. People calling into New York had problems getting through because most of the circuits where busy. After this terrible act of terrorism numerous government agencies realize it was necessary to have emergency back up communications in the form, which do not rely on local phone systems.
INTRODUCTION:
Communication is defined as exchange of thoughts, messages, or information, as by speech, signals, writing, or behavior.
Types of communication systems:
Communication systems are broadly classified as
• Wired
• Wireless
An advanced wireless communication system includes the following types;
• Satellite communication
• Mobile communication
And now narrowing down to satellite communication:
• Satellite phone
• Global positioning system
SATELLITE PHONE:
A telephone that transmits and receives from satellites that provides coverage around the world. Over eighty percent of the land on earth plus any body of water (we're talking oceans here) is without sufficient landline connection, depending on the architecture of a particular system, coverage may include the entire Earth, or only specific regions. With a satellite phone we are able to communicate with anyone with a phone number from almost anywhere. The sat phone more closely resembles our portable home phone or one of those clunky cell phones from fifteen years ago.
“Iridium was the first satellite phone company”.
An actual satellite phone can also be referred to by professionals in the satellite service field as a terminal or ‘earth station’. Some satellite phones can be chunky and reminiscent of the type of cell phones that were used in the 1980’s, but not all are made that way. Satellite phone shapes and sizes are changing much in the same way that digital phones have over the past decade. These are popular on expeditions into remote areas where terrestrial cellular service is unavailable.
A fixed installation, such as used shipboard, may include large, rugged, 9rack-mounted electronics, and a steer able microwave antenna on the mast that automatically tracks the overhead satellites.
The Need for Satellite Phone Systems
There are only two ways to hook up two telephones in different parts of the world: they can be connected by a cable which runs on the surface of the earth and under the sea, or they can be connected by radio. Not every place on the earth is served by a cable connection to the Public Switched Telephone Network (PSTN), and thus some locations must either have no telephone service or be connected to the PSTN by a radio link.
Modern cellular phones in the industrial countries mostly work in the cities and on the major highways. This is because each cell is a radio page link from the cell phone to the PSTN; and if a cell phone user is located where there are no cells, there is no service.
Because the earth is round, and because most radio waves travel in straight lines, it is not possible to form a direct radio page link to a telephone or a gateway to the PSTN which is located over the horizon. An exception to this rule are the low frequency bands which can follow the curvature of the earth, but these frequencies were all allocated for other purposes decades ago and are not generally available for telephone service. Also it is possible to have a line of radio relay stations that stretch along the earth, but these are only practical for a large number of circuits carried by the PSTN. They play a similar role to the surface cables of the PSTN and are not generally available to individual subscribers.
Almost all of the world-wide telephone voice traffic is currently carried by surface and under-sea cables. This has now changed because satellite phones have now become operational.
