Dynamic Range Enhancement of High-Speed Data Acquisition Systems

Electronic waveforms exist that exceed the capabilities of state-of-the-art data acquisition hardware that is commonly available. The electronic waveforms that need to be measured simultaneously contain wide bandwidth, high frequency content, a DC reference, high dynamic range, and a high crest factor. The NASA Glenn high-speed data acquisition system creates a voltage compression effect with a custom transfer function that is adapted to the voltage range, frequency bandwidth, and electrical impedance of both the test article and data acquisition device. The compression transfer function is later reversed (or decompressed) with a software algorithm to restore the original signal's voltage from the acquired data. The data is thus improved via better signal-to-noise ratio, better low-amplitude accuracy, better resolution, and preservation of high-frequency spectral content. The circuit can be realized with either passive components or both active and passive components. Either realization is specialized for the test article and data acquisition hardware. This is an early-stage technology requiring additional development. Glenn welcomes co-development opportunities. Innovators at NASA's Glenn Research Center have developed a technique using reversible non-linear amplitude compression to overcome hardware limitations of common high-speed data acquisition systems. The NASA Glenn technique measures electronic signals with high dynamic range, wide bandwidth, and high frequency. The technique implements a custom electronic circuit applied between the input of a data acquisition device, such as an oscilloscope, and a test article to be measured. The Glenn innovation also includes a software-based algorithm that is applied to the data acquired through the applied circuit and the data acquisition system.