Mobile Phone Invention
Wednesday, October 31, 2007 8:45
Mobile phones are used by millions of people across the world. It is an easy communication way, in which you can talk to anyone on the planet. Mobile phones of this modern world are provided with incredible functions which depend on its model.
• It can store information of contact.
• It has reminders setting to remind you about anything.
• Calculator and e-mail facility and other integrated devices like GPS receivers MP3 players are also present in the latest handsets.
• Internet information is available.
• Play games, watch TV, and send text messages.
Mobile phone was invented in the year 1876 by Alexander Graham. It is interesting to know that mobile phone was actually a radio in its early stage. In earlier days, in radio telephone system was installed in cars of those who really needed mobile communications. In this system one central antenna tower per city is used to provide 25 channels. The best way to understand is to compare it to a CB radio or walkie talkie
Comparison of CB Radio or a walkie -talkie:
• CB Radio and walkie-talkie is a half duplex device. It uses same frequency and only one person can talk at a time.
• One channel is available in Walkie-talkie whereas 40 channels are provided in CB radio.
• Walkie-talkie uses 0.25 watt transmitter to transmit range about 1 mile. But CB radio with its high power can transmit about 5 miles using its 5 watt transmitter.
• Duplex voice channels are available in the mobile phone system, which uses one-seventh of the available channels.
• A mobile phone gets 832 radio frequencies to use in a city.
• 395 voice channels are per mobile phone carrier, as it has two duplex channel frequencies per call.
Digital Mobile Phone:
• Millions of calculations per second are processed in the modern digital mobile phones which compress and decompress the voice stream.
Take notice over the digital mobile phone in individual parts:
• A circuit Board which contains brains of the phone.
• An antenna, microphone, LCD display, speaker, battery.
• Mobile phone consisted of ROM and flash memory chips in it which stores the operating system such as phone directory. Now mobile offer built-in phone directories, calculations and games and some incorporate PDA or Web Browser.
Problems
• It is non-repairable if any internal corrosion part of the phone gets wet.
• If it gets extreme heat in a car, it can damage the battery.
