Radio Receive characterization
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Desensitization:
For even values of n distortion
components consists of DC component.
So in case of strong distortion this component may get multiplied with the desired signal resulting in lowering of the average gain
of the receiver.
Cross modulation:
Presence of a strong interference with weak signal can result in cross modulation. In this scenario the amplitude of interference gets transferred to amplitude of weak signal. This generally results in second order intermodulation components.
Spurious Outputs:
These are unintended signals generated by the receiver without receiving any input signal.
Gain Control:
Gain control circuitry is used to control the quality of input signal over a wide range of input signal levels.
Noise:
Main source of noises
Thermal Noise (N= kTB):
This kind of noise is generated in resistors due to agitation of charge carriers. This random generation of current due to agitation of charge carriers results in random voltage which causes thermal noise.
Shot Noise:
There are primarily two conditions which causes Shot noises in the system.
Potential barrier over which charge carriers hop
Direct current
1/f Noise (Flicker noise)
Barkhausen Noise (Specific to magnetic materials)
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