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# Learn How to Calculate Antenna 3db Bandwidth - Tutorial

## How to Calculate Antenna 3db Bandwidth - Definition, Formula and Example

#### Definition:

Bandwidth is a range within a band of frequencies or wavelengths. It describes the maximum data transfer rate of a network and it calculates how much data can be sent over a specific connection in a given amount of time.

#### Formula:

where, Q = Quality factor

#### Example :

An antenna has a center frequency 200Hz and quality factor 1.2.Calculate the 3 DB bandwidth for the antenna.

###### Given,

f0 = 200Hz Q = 1.2

3 dB Bandwidth

#### Solution

###### Step 1:

Let us first calculate the value of lower cutoff frequency (f1) and upper cutoff frequency (f2).

 f1 = 200 x (√1+(1/4 x 1.2 x 1.2) - 1/(2 x 1.2)) = 200 x (√1+0.1736 - 1/2.4) = 200 x (1.0833-0.4167) = 200 * 0.6666 = 133.32
 f2 = 200 x (√1+(1/4 x 1.2 x 1.2) + 1/(2 x 1.2)) = 200 x (√1+0.1736 + 1/2.4) = 200 x (1.0833+0.4167) = 200 * 1.5 = 300
###### Step 2:

Now, substitute the values in the BW (bandwidth of a circuit) formula, BW = 300 - 133.333 BW = 166.667

#### Related Calculator:

Learn how to calculate the 3dB antenna bandwidth and cutoff frequency in this tutorial, given with the definition, formula and example.