Initial (Mach–Zehnder) configuration for a single-channel setup

1. Wavelength Division Multiplexing (WDM) Laser VibrometerSignal Conditioning and ProcessingFritz BekkadalCEO Gersemia

2. Initial (Mach–Zehnder) configuration for a single-channel setup

3. Demodulation and signal conditioning Coherent homodyne approach

4. Quadrature demodulator

5. Baseband conditioning and ADC • The gain adjustments of the I and Q channel amplifiers should be coupled, and preferably be performed electronically. • Initial estimations indicate a gain in the order of 10-20 dB.

6. ADC Front-end circuit

7. ADC Front-end design BW ≥ 10 MHz

8. ADC

9. Signal-to-Noise Ratio (SNR) • As a ’rule-of-thumb’: •  at least an 8 bit ADC is required • …but due to the ADC Dynamic Range (DR) requirements at least a 12 bit ADC is recommended !

10. ADC Dynamic Range (DR) • DRQ> 60 dB is jugded a minimum with signal compression? •  at least a 12 bit ADC is required • Signal compression: • Large DC and reflections in the collimator’s vicinity to be suppressed?

11. Example of ADC saturation