what is bandwidth exactly?can anyonetell me with eg?

Answer 1

A lot of people have asked me that question before, related to the so called "internet speed"...

First of all, it doesn't have anythings to do with speed! The best analogy that i found that allows people to understand what bandwidth is all about is compare the internet access to a pipe (or a hose with running water).

Basically, what you have when you have more bandwidth is a larger cross-section area, which is another way to say a bigger hose (in diameter, not length). Although the water keeps flowing at the same speed, since the pipe is larger, more water can pass in the same amount of time. If you have a bucket at the end of the hose, it will fill much faster, even with the water flowing at the same "speed".

Applying this to internet "speed", the computer (bucket) gets more information per second (more water), not because information travels faster, but because a lot of information can pass trough without having to "wait it's turn" (the hose is bigger)

Hope it helped...

PS: A Deen's tunnel example is easy to understand too... good analogy, never thought of that one. However, bandwidth is measured in bits per second, or nowadays more commonly in megabits per second (Mbps), and not bytes or kilobytes or megabytes (per second, you forgot that to), which would appear as KBps or MBps.

Answer 2

The "bandwidth" is just the commonly used word for for describing the width of something which is in the most abstract way a "band". As you ask in the physics section: In many places physicists describe something as a bandwidth: In solid state physics for example the width of the band structure of a material (the energetic differences between top and bottom of valence- or conductance band). In spectroscopy the different parts of a spectrum are also called bands, and of course their width a "bandwidth", there are several other occasions where the word is used. Others have already explained the usage of that term (which is closely related to the usage in spectroscopy) Internet connections.

So unless you ask more specific: The bandwidth is the width of a band ;)

Answer 3

If you are asking in context to the bandwith of internet providers or something similar, then this refers to the volume of "traffic" that can be transmitted through the material (usually a cable or wire or through radio-waves). An example would be if you treat the cable like a tunnel, then the bandwidth refers to the number of cars that could travel through the tunnel in a given period of time. So if the tunnel has 6 lanes then it has a higher "bandwidth" than a tunnel with 2 lanes. For internet communication bandwidth is normally measured in bytes (or kilobytes, etc.).

Answer 4

There are a lot of definitions but the primary one from the analog world is that range of frequencies in a system for which the response/power content of the system/signal is greater than one half the power at the peak frequency. Try this write up --

http://en.wikipedia.org/wiki/Bandwidth

Answer 5

Put very simply Its a range of frequencies over which the gain is constant - i.e. which the power is constant.

An example is when something outputs say a range of frequencies from 10MHz to 20MHz and power output is constant, and the centre frequency is 15MHz, the bandwidth is 20-10=10MHz, and fractional bandwidth is

10/15MHz=66.67%