Special Transient Testing Windows. In the early ’70s, the most
important signal processing development for impact testing was
the development of force and exponential windows. This development was the fallout from work being done by Ron Potter, who
was the person at HP primarily responsible for the development of
the HP 5450 series Fourier analyzer system. He was the real guru
of Fourier analysis in the late ’60s and ’70s. As part of one of his
activities, he was developing a parameter estimation algorithm for
extracting modal parameters. He was trying to get starting values