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The evolution of the cell phone A2B

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Ahmad Borham
Ahmad Borham

The document provides an overview of the history and technology behind cellular phones. It discusses how cellular phone systems work by dividing cities into small cells that reuse frequencies for millions of simultaneous calls. Each cell uses a unique set of radio frequencies to avoid interference. As users move between cells, their phone seamlessly hands off communication to the new cell's frequency. The document also examines components like transmitters, control channels, and switching offices that facilitate cellular communication. Finally, it briefly touches on technologies like Bluetooth that enable wireless connectivity between devices.

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The evolution of the cell phone A2B
Some facts  History of the Cellular Phone  More about a cellphone  Reason for its name  Analog vs. Digital  Bluetooth 
A mobile phone is designed to operate at a maximum  power level of 0.6 watts. A household microwave oven uses between 600 and 1,100 watts. In 1994, 16 million Americans subscribed to cellular phone  services. Today, more than 110 million Americans are subscribers. Some experts predict that worldwide subscribership will reach 1.2 billion people by 2005. In a 2005 University of Michigan study, 83 percent said cell  phones have made life easier, choosing it over the Internet (76 percent). But an additional 60 percent said they find cell phones somewhat irritating when used in public. The BBDO survey found that 75 percent of cell phone  owners had it turned on and within reach during their waking hours, 59 percent wouldn't think of lending their cell phone to a friend for a day, 26 percent said it was more important to go home to retrieve a cell phone than a wallet.
In 1843 a man by the name of Michael Faraday  studied to see if space could conduct electricity. In the year of 1865, Doctor Mahlon Loomis was the  first person to communicate through wireless atmosphere. He came up with the idea of transmitting and receiving  messages through atmosphere as a conductor. In 1973 martin copper came up with Motorola.  In 1977 the first cell phone was made in Chicago.  When it first came out 2000 people was given a free trial. 
One of the most interesting things about a cell phone is  that it is actually a radio -- an extremely sophisticated radio, but a radio nonetheless. The genius of the cellular system is the division of a city  into small cells. This allows extensive frequency reuse across a city, so that millions of people can use cell phones simultaneously. In a typical analog cell-phone system in the United States,  the cell-phone carrier receives about 800 frequencies to use across the city. The carrier chops up the city into cells. Each cell is typically sized at  about 10 square miles (26 square kilometers). Cells are normally thought of as hexagons on a big hexagonal grid
A single cell in an analog system uses one-seventh of the  available duplex voice channels. That is, each cell (of the seven on a hexagonal grid) is using one-seventh of the available channels so it has a unique set of frequencies and there are no collisions: A cell-phone carrier typically gets 832 radio frequencies to use in a  city. Each cell phone uses two frequencies per call -- a duplex channel --  so there are typically 395 voice channels per carrier. (The other 42 frequencies are used for control channels -- more on this later.) Therefore, each cell has about 56 voice channels available.  In other words, in any cell, 56 people can be talking on their  cell phone at one time.
Analog cellular systems  are considered first- generation mobile technology, or 1G. Digital transmission  methods (2G), the number of available channels increases. For example, a  TDMA-based digital system can carry three times as many calls as an analog system, so each cell has about 168 channels available.
The major components :  Cell phones have low-power transmitters in them.  Many cell phones have two signal strengths: 0.6 watts and 3  watts For comparison, most CB radios transmit at 4 watts. 
When you first power up the phone, it listens for an  SID (system identification #). The control channel is a special frequency that the  phone and base station use to talk to one another about things like call set-up and channel changing. If the phone cannot find any control channels to listen  to, it knows it is out of range and displays a "no service" message.
When it receives the SID, the phone compares it to the SID  programmed into the phone. The phone knows that the cell it is communicating with is part of  its home system. Along with the SID, the phone also transmits a registration  request, and the MTSO (Mobile Telephone Switching Office) keeps track of your phone's location in a database - - this way, the MTSO knows which cell you are in when it wants to ring your phone. The MTSO gets the call, and it tries to find you. It looks in  its database to see which cell you are in. The MTSO picks a frequency pair that your phone will use  in that cell to take the call.
The MTSO communicates with your phone over the  control channel to tell it which frequencies to use, and once your phone and the tower switch on those frequencies, the call is connected. Now, you are talking by two-way radio to a friend.  As you move toward the edge of your cell, your cell's base  station notes that your signal strength is diminishing. The base station in the cell you are moving toward (which  is listening and measuring signal strength on all frequencies, not just its own one-seventh) sees your phone's signal strength increasing. The two base stations coordinate with each other through  the MTSO, and at some point, your phone gets a signal on a control channel telling it to change frequencies. This hand off switches your phone to the new cell. 
There are lots of different ways that electronic  devices can connect to one another: Component cables  Electrical wires  Ethernet cables  WiFi  Infrared signals  A Bluetooth connection is wireless and automatic,  and it has a number of interesting features that can simplify our daily lives.
Bluetooth takes small-area networking to the next  level by removing the need for user intervention and keeping transmission power extremely low to save battery power. Bluetooth is essentially a networking standard that  works at two levels: Provides agreement at the physical level -- Bluetooth is a  radio frequency standard. Provides agreement at the protocol level 
Any Questions 

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The evolution of the cell phone A2B

  • 2. Some facts  History of the Cellular Phone  More about a cellphone  Reason for its name  Analog vs. Digital  Bluetooth 
  • 3. A mobile phone is designed to operate at a maximum  power level of 0.6 watts. A household microwave oven uses between 600 and 1,100 watts. In 1994, 16 million Americans subscribed to cellular phone  services. Today, more than 110 million Americans are subscribers. Some experts predict that worldwide subscribership will reach 1.2 billion people by 2005. In a 2005 University of Michigan study, 83 percent said cell  phones have made life easier, choosing it over the Internet (76 percent). But an additional 60 percent said they find cell phones somewhat irritating when used in public. The BBDO survey found that 75 percent of cell phone  owners had it turned on and within reach during their waking hours, 59 percent wouldn't think of lending their cell phone to a friend for a day, 26 percent said it was more important to go home to retrieve a cell phone than a wallet.
  • 4. In 1843 a man by the name of Michael Faraday  studied to see if space could conduct electricity. In the year of 1865, Doctor Mahlon Loomis was the  first person to communicate through wireless atmosphere. He came up with the idea of transmitting and receiving  messages through atmosphere as a conductor. In 1973 martin copper came up with Motorola.  In 1977 the first cell phone was made in Chicago.  When it first came out 2000 people was given a free trial. 
  • 5. One of the most interesting things about a cell phone is  that it is actually a radio -- an extremely sophisticated radio, but a radio nonetheless. The genius of the cellular system is the division of a city  into small cells. This allows extensive frequency reuse across a city, so that millions of people can use cell phones simultaneously. In a typical analog cell-phone system in the United States,  the cell-phone carrier receives about 800 frequencies to use across the city. The carrier chops up the city into cells. Each cell is typically sized at  about 10 square miles (26 square kilometers). Cells are normally thought of as hexagons on a big hexagonal grid
  • 6. A single cell in an analog system uses one-seventh of the  available duplex voice channels. That is, each cell (of the seven on a hexagonal grid) is using one-seventh of the available channels so it has a unique set of frequencies and there are no collisions: A cell-phone carrier typically gets 832 radio frequencies to use in a  city. Each cell phone uses two frequencies per call -- a duplex channel --  so there are typically 395 voice channels per carrier. (The other 42 frequencies are used for control channels -- more on this later.) Therefore, each cell has about 56 voice channels available.  In other words, in any cell, 56 people can be talking on their  cell phone at one time.
  • 7. Analog cellular systems  are considered first- generation mobile technology, or 1G. Digital transmission  methods (2G), the number of available channels increases. For example, a  TDMA-based digital system can carry three times as many calls as an analog system, so each cell has about 168 channels available.
  • 8. The major components :  Cell phones have low-power transmitters in them.  Many cell phones have two signal strengths: 0.6 watts and 3  watts For comparison, most CB radios transmit at 4 watts. 
  • 9. When you first power up the phone, it listens for an  SID (system identification #). The control channel is a special frequency that the  phone and base station use to talk to one another about things like call set-up and channel changing. If the phone cannot find any control channels to listen  to, it knows it is out of range and displays a "no service" message.
  • 10. When it receives the SID, the phone compares it to the SID  programmed into the phone. The phone knows that the cell it is communicating with is part of  its home system. Along with the SID, the phone also transmits a registration  request, and the MTSO (Mobile Telephone Switching Office) keeps track of your phone's location in a database - - this way, the MTSO knows which cell you are in when it wants to ring your phone. The MTSO gets the call, and it tries to find you. It looks in  its database to see which cell you are in. The MTSO picks a frequency pair that your phone will use  in that cell to take the call.
  • 11. The MTSO communicates with your phone over the  control channel to tell it which frequencies to use, and once your phone and the tower switch on those frequencies, the call is connected. Now, you are talking by two-way radio to a friend.  As you move toward the edge of your cell, your cell's base  station notes that your signal strength is diminishing. The base station in the cell you are moving toward (which  is listening and measuring signal strength on all frequencies, not just its own one-seventh) sees your phone's signal strength increasing. The two base stations coordinate with each other through  the MTSO, and at some point, your phone gets a signal on a control channel telling it to change frequencies. This hand off switches your phone to the new cell. 
  • 12. There are lots of different ways that electronic  devices can connect to one another: Component cables  Electrical wires  Ethernet cables  WiFi  Infrared signals  A Bluetooth connection is wireless and automatic,  and it has a number of interesting features that can simplify our daily lives.
  • 13. Bluetooth takes small-area networking to the next  level by removing the need for user intervention and keeping transmission power extremely low to save battery power. Bluetooth is essentially a networking standard that  works at two levels: Provides agreement at the physical level -- Bluetooth is a  radio frequency standard. Provides agreement at the protocol level 