Analyzing data from analog/digital converters (ADCs) requires the use of windowing functions for spectral estimation and analysis, but different windows suit different purposes. National Semiconductor's WaveVision 5 software provides a family of mathematically simple windowing functions that spans a fundamental tradeoff and provides the flexibility to meet a wide range of user applications.

We are publishing a two-part article on this important topic, in pdf document format:

Part 1 (click here) is a discussion on spectral analysis that presents the need for data windowing as well as the effect of windowing functions in the time and frequency domain.
Part 2, which will be posted on February 11, 2009, presents the Cosine-Sum family of windowing functions available in WaveVision 5, the application of these windows, and an elementary discussion on the mathematics behind the calculation of performance metrics such as the SNR.

About the Author
Josh Carnes is an applications engineer with National Semiconductor's Strategic Signal Path Group, based in Ft. Collins, Colorado. He received his BSEE and MSEE degrees from Oregon State University in 2004 and 2007, respectively, with research focusing on low-voltage pipelined ADC design techniques. His interests include cellular base station subsystems, wireless communications, as well as automated testing and analysis of ADCs.

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