Antenna amplifier

Many devices have an RF amplifier stage in their circuitry, that amplifies the antenna signal, these include, but are not limited to; radios, televisions, mobile phones and Wi-Fi and Bluetooth devices.

Typical signal noises include: ambient background noise (electric brush noise from electric motors, high voltage sources from, for example a gasoline engine ignition, or large dispersed currents in the vicinity of the desired reception electric fence).

To add, consideration must be taken for the noise generated by the amplifier itself and all other electrical noise which may be generated by the device that is to receive a signal, for example a lot of consideration has to go into mobile phone circuitry design to eliminate as much noise from its own circuitry in order to not disturb the desired transmission signals from its own antenna(ae).

[1] Its draw backs are that any noise is usually amplified as well, and a common result from this is amplification of ghost images (for analog signals), and any other perturberances that may be existing locally or even extra terrestrially like the Cosmic microwave background radiation for devices that work in that frequency range.

The key to a "good" level of input at your receiver with the minimum amount noise includes many design considerations in an electrical amplifier.