Automatic gaincontrol fortheuniform amplitude ofinterferent signal in aLaserDoppler Vibrometer
Seonggu Kang, Hyun-Seung Choi, Hee-Sun Yoon · 2006
Theamplitude variation oftheinterferent signal canbecaused since theobject surface isuneven and thereaction angle canbevaried according totheobject motion. Theamplitude variation causes anerror inthesignal processing algorithm. Thiserror distorts theoutput signal. Inorder toeliminate this dependence oftheinterferent signal ontheamplitude variation, twokinds ofanalog feedforward automatic gaincontrol(AGC) whichhavemoresimple structure andhigher bandwidth thanthat ofthefeedback method areproposed. Electronic circuits areconstructed to implement theproposed AGC algorithms. Thebrief analysis, themeasurement schemeofthesystem, andthe experimental results oftheAGCsusing alaser Doppler vibrometer arepresented. Theydemonstrate that theproposed AGCsareproven tomakethesystem robust totheamplitude variation oftheinterferent signal.