The December 2022 issue of IEEE Spectrum is here!

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Pulse Prediction

The Back Story

2 min read

For IEEE Fellow Monte Ross, the dedication last spring of a new telescope in Harvard, Mass., is a kind of vindication. The facility, designed and operated by Harvard University’s Paul Horowitz, is the first to be specially crafted to search for signals of light, rather than radio, from intelligent extraterrestrial beings [see Ross's article, "The New Search for E.T. ," in this issue].

Although Ross has no personal stake in the new instrument, for more than four decades he has championed the idea of searching the cosmos for pulsed optical signals. ”With the advent of the laser [in 1960], I realized that it made a lot of sense for use in communication,” he told IEEE Spectrum.

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From WinZips to Cat GIFs, Jacob Ziv’s Algorithms Have Powered Decades of Compression

The lossless-compression pioneer received the 2021 IEEE Medal of Honor

11 min read
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Photo of Jacob Ziv
Photo: Rami Shlush
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Lossless data compression seems a bit like a magic trick. Its cousin, lossy compression, is easier to comprehend. Lossy algorithms are used to get music into the popular MP3 format and turn a digital image into a standard JPEG file. They do this by selectively removing bits, taking what scientists know about the way we see and hear to determine which bits we'd least miss. But no one can make the case that the resulting file is a perfect replica of the original.

Not so with lossless data compression. Bits do disappear, making the data file dramatically smaller and thus easier to store and transmit. The important difference is that the bits reappear on command. It's as if the bits are rabbits in a magician's act, disappearing and then reappearing from inside a hat at the wave of a wand.

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