Synthetic quadrature phase detector/demodulator for Fourier transform spectrometers.
A method is developed to demodulate (velocity correct) Fourier transform spectrometer data that are taken with an analog to digital converter that digitizes equally spaced in time. This method makes it possible to use simple low-cost, high-resolution audio digitizers to record high-quality data without the need for an event timer or quadrature laser hardware and makes it possible to use a metrology laser of any wavelength. The reduced parts count and simple implementation make it an attractive alternative in space-based applications when compared to previous methods such as the Brault algorithm.
Campbell
Joel
J
NASA Langley Research Center, MS 488, Hampton, Virginia 23662, USA. joel.f.campbell@nasa.gov