Engineers solve 50-year-old puzzle on signal processing

Researchers have developed the first inverse chirp-z transform (ICZT) algorithm for signal processing. These solutions could not be found in the last 50 years due to high complexity.

In order for us to listen to streaming music,make a cell phone call, use the Internet, or take digital pictures, modern electronic devices use a signal processing algorithm known as the fast Fourier transform (and its inverse). In 1965, a more universal generalized version of it, called the chirp-z transform, was developed.but so far there has been no reverse solution for her.

However, recently two engineers from State UniversityIowa published a paper describing the long-awaited inverse chirp-z transform algorithm and evaluating modifications that improve its numerical stability for a subset of the parameter space. The principle of operation of this pair of algorithms can be compared to the operation of a system of two prisms, where one divides light into a color spectrum, and the second converts it back to white.

Scientists say the algorithm matchesthe computational complexity and speed of its analogue, it can be used with exponentially decreasing or growing frequency components (as opposed to IFFT) and that it has been checked for numerical accuracy.

Engineers recently created the world's first all-optical transistor with a switching frequency of 2 THz, which is capable of operating at room temperature.

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