How did the first cell phones work?

First cell phones use a fixed frequency for a certain user. Such as, 900.1 MHz is for me, for you, 901.2 MHz like this, This is called AMPS or TACT, it is 1st generation.

Clearly, there cannot be lot of users in this way, because frequencies are limited.

Later, one fixed frequency, was divided into 8 parts ( fancy name: time slot). So, by using 900.1 , now 8 persons can use it. This is called GSM sytem or 2nd generation.

Then, in one fixed frequency, 256 codes ares introduced, Each user take one code and send his info to another. So, maximum 256 user can use 900.1 frequency now. This is called UMTS or 3rd generation .

Moving on, multiple antenna, receiver are added on every sides , so a user can have multiple signal receiving same time, if those r empty at moment. This is called LTE or 4th generation.

Going more, each side is given IP address , so every machine, human, appliance can now be connected to telecommunicaiton network - ( fancy name: ‘Internet of things' ) . This is called 5th generation ( no commercial name is still given).


What life lesson changed you the most?

I am the only one responsible for my future, and life will not give you anything unless you fight really hard for it.Some circumstances in your life will make you feel a little bit depressed, and you're going to think that the future will be hopeless, that's when I realized that the only way I

How does a cellular phone battery meter work?

Volt meters monitor the amount of voltage being put out by the battery. But regarding cell phone battery meters, a lot of things can affect this reading (including the energy it takes to run the cell phone battery meter app, and the temperature of the phone). So it's important to find a cell phone battery meter app that

What general changes would you like to see in the Internet in the next 10 years?

The main change I would like to see is not technical, or anything to do with cool features. Development and technical innovations will occur, you can bank on it.The principal change I long for is a cultural change, I look for people becoming more involved with creating new platforms, additional specialized social media alternatives.