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Communication system (2) CT1401. Lecture-9 : mobile phone By : A fnan alayyash Supervision : Dr .Ouiem Bchir. Outline. Definition mobile phone How to work mobile phone Type to mobile phone The basics of mobile phone Protocol used in mobile phone Advantages and Disadvantages.
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Communication system (2) CT1401 Lecture-9 : mobile phone By : Afnan alayyash Supervision : Dr.Ouiem Bchir
Outline Definition mobile phone How to work mobile phone Type to mobile phone The basics of mobile phone Protocol used in mobile phone Advantages and Disadvantages
A mobile device, or handheld, is an electronic device that enables some kind of computing, and which is small enough to be easily carried around. These devices are quite pervasive nowadays. Commonly used mobile devices include cell phones, Personal Digital Assistants (PDAs), and multimedia players
a mobile device has an operating system (OS) , and can run various types of application software, known as apps. most handheld devices can also be equipped with Wi-Fi, Bluetooth, and Gps capabilities that can allow connections to the internet .
How do mobile phones work? Imagine calling a friend on the other side of town. As you chat away, your phone converts your voice into an electrical signal, which is then transmitted as radio waves and converted back into sound by your friend’s phone. In order to remain portable, mobile phones need to have relatively compact antennas and use a small amount of power
types of mobile phone • 1) Mobile phone • 2) Paging
1) MOBILE PHONE used to facilitate voice conversations, as well as text messages. that's where more than of his company for the his industry
2) Paging : through which telephone numbers or short messages could be received. pagers are still used by people in emergency and medical services
The basics of mobile work 1) Duplex 2) Channel 3) Range
1) Duplex mobile works full-duplex system and this means that there is a dedicated frequency to talk to another frequency and different to listen to, which means that both people they can talk at the same time.
:2) Channelsmobile devices to deal with more than 1664 channel 3) Range mobile devices operate within cells which have divided the city and can transform from a cell to another whenever has moved from one place to another during use, and this means that the extent to which it operates a mobile device is very large and you can talk with anyone a distance hundreds of kilometers without interruption contact
protocol used in mobile • Use Mobile System number of protocol, but the most important: 1) 2G 2) 3G 3) 4G 4) FDMA
2Gis short for second-generation wireless telephone technology three primary benefits of 2g networks over their predecessors were that phone conversations were digitally encrypted; 2g systems were significantly more efficient on the spectrum allowing for far greater mobile phone penetration levels 2g technologies enabled the various mobile phone networks to provide the services such as text messages, picture messages and mms (multi media messages).
3Grefers to the third generation of developments in wireless technology, especially mobile communications. the third generation, as its name suggests, follows the first generation (1g) and second generation (2g) in wireless communications. while 3g is generally considered applicable mainly to mobile wireless, it is also relevant to fixed wireless and portable wireless. a 3g system should be operational from any location on, or over, the earth's surface, including use in homes, businesses, government offices, medical establishments, the military,
4Gis the short term for fourth-generation wireless, the stage of broadband mobile communications that will supersede the third generation (3g). will be among 4g's distinguishing features. fourth generation networks are likely to use a combination of wimax and wi-fi.
(FDMA) frequency division multiple access is the division of the frequency band allocated for wireless cellular telephone communication into 30 channels, each of which can carry a voice conversation or, with digital service, carry digital data. FDMA is a basic technology in the analog advanced mobile phone service (amps), the most widely-installed cellular phone system installed in north America. with FDMA , each channel can be assigned to only one user at a time
: ADVANTAGES1) you can chat & video conference 2) good for emergencies3) can be used worldwide4) you can listen to music, text, play games 5) you can surf internet & connect with the whole world 6) you can take pictures
Disadvantages:1) mobile phones can be expensive *2) the battery runs out3) possible cause a damage healthy
Transmission of data:http://www.youtube.com/watch?v=KymIDyQiXZIThe difference between 2G and 3G and 4G http://www.youtube.com/watch?v=vwywdylnbEo
D-channel a delta channel (d channel) is a signaling channel in an integrated services digital network (isdn). d channels take care of call set up, control and maintenance. the basic isdn channel holds two bearer channels (b channels) and one d channel. these contain data that relates to signaling errors, framing and other management signals. the speed of a d channel is 16 kbps for basic rate interface and 64 kbps for primary rate interface. d channels carry signaling between a customer’s terminal device and a carrier’s end-switching office. signaling information with end-to-end significance travels between the carrier switching office on the carrier's common channel-signaling network and the destination terminal through the receiving user’s d channel.significance