Volume 9, Number 6 • November/December 2001 • Advanced Technologies

R&D 100 Awards Recognize Hilbert Huang Transform

For 39 years, the R&D 100 Awards program has recognized the developers of the top 100 technologically significant products introduced into the marketplace over the past year. This year the Hilbert Huang Transform (HHT), developed by Norden Huang of the NASA Goddard Space Flight Center in Greenbelt, Maryland, was selected for this prestigious award.

HHT is also known as the Empirical Mode Decomposition (EMD) method. This technique decomposes a complicated set of data into a finite, smaller number of functions. The smaller functions are oscillation modes or vibrations contained in the original data and are associated with the time scale of the data. The Hilbert Transform creates an energy-frequency-time distribution of these decomposed data.

HHT is groundbreaking because it produces more precise, meaningful and interpretable results of nonlinear and non-stationary data. Nonlinear data for events ranging from earthquakes to heart arrhythmias have long been analyzed, but their underlying phenomena had to be frozen in time and space. HHT is the first adaptive method for measuring things that don’t stay still and don’t follow regular patterns. The result is a more precise definition of particular events in time-frequency space and a more meaningful interpretation of underlying dynamic processes than can be obtained with historical methods. Q

For more information, contact Evette Conwell at Goddard Space Flight Center, 301/286-0561, Evette.Conwell@gsfc.nasa.gov. Please mention you read about it in Innovation.

NASA Official: Jonathan Root • Web Design: Printing & Design Office, NASA Headquarters • Credits