Computer 101: How does a Modem (Modulator – Demodulator) Works?

This simple device has been the one of the key to allowing our home to have access to the internet, therefore it is only complementary that we need to learn and understand how this device called a modem works. First of all let’s focus on the term or word itself where the device gets it’s name MODEM or Modulator – Demodulator. To get a really pretty good idea on hoe these device works focus your mind on the word Modulator. What does this word means? I quick search around the internet will give us the following many result including the word modulation. Modulation is very much related to modulator.

From there we pick out the term modulation which a process, modulation is a process while modulator is the device that does the processing. Modulation is the thing that the Modem do to make it possible for us to receive and send our data from our computer over the internet which can be compose of a lot of things from the telephone wire, satellite connection, under water submarine cable and many more. It is best to know that while we access the internet by reading our favorite news online or chatting, or reading our email the data that we sent and receive will have traveled hundreds our thousand of mile from it’s current location and suddenly appearing in front of your computer screen.

Why do we need a device called a modem to connect to the internet? I myself also struggled which these during my early learning experience. To put it simply a computer only understands one signal and that signal is called a digital signal which has only two information 1 and 0. From these two everything’s can be represented by a series of 1 and 0. But there a problem the digital signal cannot be transmitted via the copper wire which our telephone line is connected because it only accept analog signal which can range from the negative side to zero and the positive side. From here we can see that the digital and analog signal is very different from each other. Yup and analog signal has a lot of things while a digital signal has only two things I say that’s very different. The 0 and 1 of a computer cannot be transmitted as is or by itself. It like these let’s say we are buying a product called wine from another country. We love wine and that country alone produces the best kind of wine. They know the wine we also know the wine but they need to somehow get the wine from there place to your place, now how do we do that?

First of all the wine is put in a bottle and the bottle is put in a packaging for transport. Hey that’s modulation based from the three definitions that we listed here. Let’s continue once the wine is ready for shipment it get loaded on a truck then on a place or cargo ship very big cargo ship and once that ship or plane reaches your country is it then transferred to a truck then delivered to a station where it get sorted out and according to the address of the recipient it should be in your door step by the next day. Once the wine reaches your home, we first open the package then we open the bottle and then we pour the wine on a glass then we smell it shake it up a bit and then we zip a small portion of it, yup we do not just drink the entire glass or bottle we zip small amount of it to really enjoy the wine.

It the same thing for modem the signal from the computer which 1 and 0 is put in a package then is carried or transported via a carrier signal over the world wide web and then that signal reaches the intended destination via the unique address on the information. Yes each and every data transmitted in the World Wide Web ahs each own unique address so it will not get lost much like the wine that is shipped from the source country to its country of destination. When that information reaches modem, of your computer it demodulates the information, how? Just like the wine first the carrier signal is removed then the container that carrying the information the 0 and 1 is open the information itself get assembled and is sent to the computer. Pretty nice process and all of this process going back and forth happens in blink of an eye or maybe faster. So the next time we access the internet have more patience while we wait for the information to appear in our screen for we will never know how it traveled far to get there.