The important performance characteristic of a radio receiver are as follows:

1] Sensitivity

2] Selectivity

3] Fidelity.

1] Sensitivity : Sensitivity of a radio receiver is defined as its ability to amplify weak signals, it is often defined in terms of the i/p voltage that must be applied to i/p of receiver to obtain a standard o/p power. fig below shows the sensitivity curve of a receiver.

It indicates that receiver i/p (in ev) required to obtain the same standard o/p changes with carrier frequency, the sensitivity of a radio receiver is dependent on the RF and IF amplifier stages, by increasing the gains of these stages it is possible to increase the sensitivity of a receiver.

Selectivity : The Selectivity of a receiver is its ability to reject unwanted signals, it is expressed as curve shown below: