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Constructing Prototype Lock-in Amplifier with LabVIEW & DAQ. Xiaoyu Wu 08300290011 Dept. of Physics, Fudan University. What is Lock-in Amplifier(LIA)?. Detect & Measure Signals Even with overwhelming noise Typical S/N ratio -60dB. Signal + Noise. Amplitude + Phase as DC.
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Constructing Prototype Lock-in Amplifier with LabVIEW& DAQ Xiaoyu Wu 08300290011 Dept. of Physics, Fudan University
What is Lock-in Amplifier(LIA)? • Detect & Measure Signals • Even with overwhelming noise • Typical S/N ratio -60dB Signal + Noise Amplitude + Phase as DC
Principle of LIA • Phase Sensitive Detection • Orthogonality of Sinusoidal Functions LOW-PASS FILTER
Features • Signal Frequency: ~Hz to ~kHz • Signal Amplitude: 0.005V tested • Sampling Rate: maximum 50kHz, 40kHz tested
Drawbacks • S/N Ratio • Function Generator