## What is 3D radiation pattern?

Radiation Pattern in 3D The radiation pattern is a three-dimensional figure and represented in spherical coordinates (r, θ, Φ) assuming its origin at the center of spherical coordinate system.

**What is the dimension of radiation pattern?**

The radiation pattern is defined as a mathematical function or a graphical representation of the far field (ie, for r≫2D2/λ, with D being the largest dimension of the antenna) radiation properties of the antenna, as a function of the direction of departure of the electromagnetic (EM) wave.

**Is also called as 3 dB bandwidth?**

The bandwidth of a filter or amplifier is usually defined as the difference between the lower and upper half-power points. This is, therefore, also known as the 3 dB bandwidth. There is no lower half-power point for a low-pass amplifier, so the bandwidth is measured relative to DC, i.e., 0 Hz.

### How antenna gain is measured?

* Antenna gain is measured in decibels as either dBi or dBd. dBi refers to dB away from a theoretical isotropic antenna (0), while dBd refers to dB away from a more real world reference dipole antenna with a gain of 2.15 dB.

**What information is available from a radiation pattern?**

The radiation pattern of an antenna gives us information about its receiving and transmitting properties in different directions.

**Where do we find radiation patterns?**

The far-field pattern of an antenna may be determined experimentally at an antenna range, or alternatively, the near-field pattern may be found using a near-field scanner, and the radiation pattern deduced from it by computation.

#### Why is the 3 dB frequency called so?

It’s because decibels are logarithmic, and the log (base 10) of 3 is about 50% power. So the 3 decibel cutoff is where power drops off by a half. 3 dB implies 1/2 the power and since the power is proportional to the square of voltage, the voltage will be 0,707 of the pass band voltage.