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Coherence resonance in a unijunction transistor relaxation oscillator
Md Nurujjaman1, P S Bhattacharya, A N Sekar Iyengar
1Plasma Physics Division, Saha Institute of Nuclear Physics, Bidhannagar, Kolkata 700064, India. jaman_nonlinear@yahoo.co.in
Summary
Coherence resonance in unijunction transistor oscillators was studied using normal variance (NV). Noise interference degrades coherency, but minimizing this interference can preserve oscillation coherence.
Area of Science:
- Nonlinear dynamics
- Electronic circuits
- Stochastic resonance phenomena
Background:
- Unijunction transistor relaxation oscillators exhibit complex behaviors.
- Coherence resonance is a phenomenon where noise enhances signal regularity.
Purpose of the Study:
- Investigate coherence resonance in a unijunction transistor relaxation oscillator.
- Quantify the impact of noise on oscillation coherency.
- Identify mechanisms for coherency degradation.
Main Methods:
- Experimental investigation of a unijunction transistor relaxation oscillator.
- Quantification using normal variance (NV) measurements.
- Analysis of noise amplitude effects on system coherency.
Main Results:
- Two distinct normal variance (NV) curves were observed, dependent on measurement points.
- Coherency degrades significantly at higher noise amplitudes.
- Observed degradation is attributed to direct interference between coherent oscillations and stochastic noise.
Conclusions:
- The study quantifies coherence resonance in a specific electronic oscillator.
- Direct interference between noise and oscillations is identified as the primary cause of coherency loss.
- Minimizing this interference is proposed as a method to maintain system coherency.
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