MARINTEK 1 Wavelength Division Multiplexing (WDM) Laser Vibrometer Signal Conditioning and Processing Fritz Bekkadal CEO Gersemia

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

MARINTEK Demodulation and signal conditioning 3 Coherent homodyne approach

MARINTEK Quadrature demodulator 4

MARINTEK Baseband conditioning and ADC 5 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 dB.

MARINTEK ADC Front-end circuit 6

MARINTEK ADC Front-end design 7 BW ≥ 10 MHz

MARINTEK ADC 8

MARINTEK 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 ! 9

MARINTEK ADC Dynamic Range (DR) DR Q > 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? 10

MARINTEK Example of ADC saturation 11