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Does negative resistance have negative noise?

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freetofree

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so that negative resistance+positive resistance=no noise
 

do you create the negative resistance using a circuit? i think it's impossible to cancel the noise each other
 

The two noise sources are not correlated so the noise powers add.
 

Wer u r gonna using this concept.As per oscillator ccts I think it will not introduce noise as it is used for compensating effect and stabilize the oscillation.
Please do let me know.
 

Well it is amazing to hear all these points but what i think is,
1. the negative resistance is when you increase the voltage after some specific value the current starts to decrease. If this is the case then as you see that the current is decreasing then the power will not be increasing so noise will not reduce in this case.
2. If it is like that due to some reason at the last instances the power of the input is increasing then it will definitely reduce the noise.(The negative resistance phenomenon may be observed in many well-known everyday situations where something (a being, a device etc.) containing an additional power source affects (as a proportional reaction of some disturbance) something else containing the main power source) OR (The additional source may help or impede the main one in three degrees (under-, exact- or over-). Negative resistance represents the last degree when the additional source "over-helps" or "over-impedes" the main one.)
 

immadsiddiqui said:
Well it is amazing to hear all these points but what i think is,
1. the negative resistance is when you increase the voltage after some specific value the current starts to decrease. If this is the case then as you see that the current is decreasing then the power will not be increasing so noise will not reduce in this case.
2. If it is like that due to some reason at the last instances the power of the input is increasing then it will definitely reduce the noise.(The negative resistance phenomenon may be observed in many well-known everyday situations where something (a being, a device etc.) containing an additional power source affects (as a proportional reaction of some disturbance) something else containing the main power source) OR (The additional source may help or impede the main one in three degrees (under-, exact- or over-). Negative resistance represents the last degree when the additional source "over-helps" or "over-impedes" the main one.)
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the noise power isn't the circuit power
as flatulent said, these two noise source aren't correlated, so the totle noise power is the sum of each noise
 

Do you think there exists negative noise? Or, all the noise is positive.
 

freetofree said:
Do you think there exists negative noise? Or, all the noise is positive.
Click to expand...
Noise amount is determined with noise power which is equal to (noise amplitude)², and this is always posistive no matter which sign has amplitude.
 

We only care the noise power. U can reference some book about Noise.
Vnois=√(Vnois)²
 

I think that such a device does add noise. Though we speak of negative resistance we always end up with what we call incremental resistance. Absolute resistance is always positive.
 

if you create a positive feedback resistance through the use of (-1)buffer and common gate, can you still have the neg resistance? I think this is one way to cancel out the paralell resistance in a RLC tune network.
 

Since negative resistance is created by an active circuit, it adds more noise to the circuit
 

yes, definitely. As long as you use resistive componment in your circuit, it always adds thermal noise.
 

If I have two resistors in series in a black box, like:

r1 a c 1k
r2 c b -500

then, if "c" is not accessible, it would be impossible (from a circuit theory perspective) to tell from I-V measurements of terminals "a" and "b" that this box contains anything other than a 500 Ohm resistor.

Hence, I would be surprised if the noise didn't correspond to the same 500 Ohm resistor.
 

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