Multichannel "Stroboscopic Optical Spectrum Analyser

Fig. 1. Schematic diagram of the present wave tank experiment OSA = second Optical Spectrum Analyser MOSA = Multichannel ("Stroboscopic") Optical Spectrum Analyser...

The Multichannel ("Stroboscopic") Optical Spectrum Analyser (MOSA) allows us to carry out spatial Fourier analysis of the images of a ruffled water surface. One can show (see, Appendix) that the frequency spectrum s(co) = < i cof > (<...> denotes statistical averaging) of the MOSA signal i t) can be written in the form... 

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