♧About me,I am deepak ,I graguatet in physic ,but i intrest in basic instrument ,animated work,and device system before i was join 3 d animation class and institude but i have no mony and i was finacial problem then chang my way and were get me ajob any field and gave my parformance always, i study in tybsc of Physics. Then i complite msc then wish you me success ,i hope ..and give small chance in hashnode. Thankyou hashnode team you sugest me and thanku to julia furst morgado ,she giving information for me ..if should my mistack in hashnode ,if will support me .i needed you and your support. Thankyou again.
● CELLULARPHONE :
Today ,Cellular phonees are simply the most common telecom device around The word .
Cellular phone is mobile phone .needed network for start dada and net . The alexander Graham Bell Developed the First Telliphone in the latter part of the 19th century. The some era also gave birth to thevradio , which was initially presented by ITALIAN GUGLIELMO MARCONI . The combination of this two discoveries and invention into a single turn up it more powerful device up to the early 1950's when the devlopment of a cellular phone or mobile phone started.
•OPRETING PRINSIPL:
A cellular network or mobile network is radio network call cells . In a cellular network, each haxagonal cell uses a different set of frequencies from from neighbouring cells.to avoide interference . When joined together these cells provide radio coverage over a wide geographic area . This enablels a large number of mobile phones to communicate with each other and with fixed transceivers and telliphones anywhere in the network ,via stations. The mobile srvice is also provided along the roads joining different cities .
In cellular phone the coverage area is divided into regular shaped cells , and hexagonal cells are conventional Each hexagonal cell has coverage area of 26 sq km. The cell phone carrier typically gets 832- radio frequencies to use in the city .
•PER CELL - Every cells phone uses two frequnciees,one fore transmission and other fore reception .called as duplex channels . Therfore ,there are 395 -Voice channels per carrier and remaining 42 for control channels . f3, f4. f2 ,f1,f5,. f3 ,f7 ,f6..there are six adjacement cells ,and these 6+1=7 cells have distinct frequencies .if these 395 channels are equally assigned to seven cells , then every cell would have 56 voice channels . This portrays that in any cell only 56 people can talk simultaneously . The cell phones are battery operated.Because of low power trasmission , the power consumption of the battery is low .
●WORKING OF CELL PHONE :
The cell phones have low power trasmitter about 0.3 to 3 watt and base station also has low transits low transmits low power. In every city ther is mobile teliphone switching office (MTSO) And handels every activity ofcthe base station
The cell phones have spetial code associated with them and are used to identify the phones, phon's owner ,service provider .when the phone is switched ON, it listens for special identification code (SID ). A unique 5 -digit SID is assigned to each carrier and are trasmitted control channele .when the cell phone continuosly through the base station .
When The User Gets Call, Then then it comunicates with it through the control chnnel . It informs regarding which frequency paire use to be used over control channel . Then the base station and uer phone strart communication over this frequency paire and the call is established. The control channel also informs about calling party phone number . When user is travelling and if is the edge of the cell ,then MTSO conect to the base station of the adjacent cell. This is facilitated by MTSO, which connects user to the base station of the adjacent cell.
▪︎MICROPHONE : It convrts audio signal to elecrical signal .
▪︎AMLIFIRE AND FILTER : Amplifier increse signal level of output of microphon and and filter is band limiter .
▪︎A/D CONVERTER : It digidizes the signal and furnishes It to microprocessor.
▪︎MICROPROCESSOR: The microprocessor is brain of cell phone.It parformas th voice data and gives It FSK moulator
▪︎FSK MODULATOR : FSK (Frequency-Shift Keying )is a frequency modulation schame in which digital information is transmitted through discrete frequency changes of a carrier wave .The modulated signal is then transmitted throuth the antena of cell phone to the base station. This is the complete process of transmission of user's voice
▪︎ANTENA : The Anteba is Omni directional and use fore transmission as well as reception . The party's signal is received by the antena and given to FSK detector .
▪︎FSK DETECTOR : It demodulates the signal and furnishes to microprocessor. The microprocessor parforms the data and gives to D/A convert
▪︎D/A CONVERTER : The D/A converter converts digital signal to equivalent analog signal
▪︎FILTERS AND AMLIFIRE: The filter passes particular band and the Amlifire improves signal level and use as input for speaker .
▪︎SPEAKER : The output of amplifier drives the speker and sound is generated .
▪︎RAM AND ROM : The RAM and ROM stores cell phone's operating system and other data such as phone directory ets .
▪︎FLASH MEMORY CARD : It is normally inserted externally in the cell phone . It is also called SIM CARD . It consists of system identification (SID) code and Mobile Identification Number (MIN). The SID code is checked by MTSO through the control channel for validation .
▪︎KEYBOARD : Keyboard is used for typing message for communication. However ,in smart phones onscreen keyboard appears on the bottom part of the touch screen .
▪︎LCD DISPLAY : It is liquid crystal display and have a wide range of applications in mobile phone .
The Cell Phone transmission use Frequency Division Multiple Access (FDMA), Time Division Multiple Access (CDMA). FDMA is normally used for analog transmission.
The TDMA system operate either in the 800 MHz or 1900 MHz frequency brands .
The cell phone which operate in 800 MHz (megha hartz ) as well as 1900 MHz bands are called dual band cell phones . Simillarly the cell phones which support analog as well as digital transmission are called dual mode cell phones .
□ FUNCTIONS PERFORMED BY CELL PHONES :
Modern Cell Phones can do lot of function as mentioned below
Cell Phones can make a phone call any other phone .
It stores information such as before contact number, save ilajas ,pdf file ,many apps ,like this tweeter ,Hashnode ..ets
Cell phones can keep track of youre appointments and remind youre about them .
Cell phones contain calculator
Some moddels of cell phones can send and receive e-mails
Cell phone can also browse on internet .
You can play games ,chat, play any sound files etc .on cell phones.
• FEATURES /SPECIFICATIONS
Listed below are Features and Specifiction of Philips made savvy cell phone :
900 MHz or 1800 MHz (Megha Hartz) dual band operation .
SMS Cell brodcast with upto 5 channels sellection option .
Display number of names of the incoming call .
Allow the receiver to receive and manage second call .and contnue talk with Friends and family.
Emergency call can be made with or withot SIM CARD. The standard Emergency number is 112 .
It records incoming messages (voice mail).
Call forwarding facility .It transfer call to mail box or specific number.
It is vedio chat facility ,as wats up ,face book ,instragram,and Google metting,zoom metting .
To live the better life by MOBILE PHONES.
Man is turning the happy and sad movment for family.
But ,Almost all the modern applinces available today are electric /electronics in TECH INDUSRIES COMPANY .
The different modern electronics apliances now become necessary to mankind just as their daily needs .
☆ The discrete electronics circuits are combined single INTEGRATED CIRCUIT (IC) for particukar product .
This has been possible because of advancements in electronic design. Because of the single IC .
The size and costs of the electronic control circuits are drastically reduced .
The application -oriented microprocessor are designed which include all the port keyboard,memory,display and computing requirements of the applications. This all possible because of electronics design and IC FABRICATION TECHNIQUE.