Now, in the second decade of the 21st century, digital communications pervade our society, with billions of people depending on them every day. Practically every electronically-based message we send, whether over a wire or over the airwaves, is now digital in structure. It's a profound technological shift that has occurred only fairly recently, though its lineage can be traced back to the 19th century. One of the greatest pioneers of digital communications—a man widely lauded as the father of the technology—is Solomon Golomb.
Born in Baltimore in 1932, Golomb was trained as a mathematician, obtaining his undergraduate degree from Johns Hopkins and going on to graduate work at Harvard, where he earned his doctorate. While working on matters of pure mathematics that supposedly had no practical application, specifically number theory and advanced algebra, he became interested in communications and cryptography. He began to think about how a curious mathematical phenomenon called a nonlinear shift register, or pseudorandom sequence, could be applied in those fields.
In mathematical terms, a shift register is a sequence of ones and zeroes in which the order shifts by one digit with each iteration, creating an apparently random order that still maintains a hidden, predictable sequence. The utility of such a phenomenon for creating secret codes might be obvious, but Golomb also realized that it could be supremely useful in various communications technologies. The U.S. military came to the same conclusion, and in 1956, when Golomb was hired at the Jet Propulsion Laboratory or JPL (then under the aegis of the U.S. Army), he was given the job of finding ways to control missiles with jam-proof radio signals. Golomb's shift register techniques solved that problem and soon also found ready application in other military communications and radar.
But Golomb's contributions extend far beyond the classified military realm. When JPL became part of NASA in 1958, Golomb shifted his focus to science. As satellites and space probes began to venture into Earth orbit and far beyond to the edge of our solar system, his work made possible the detection of incredibly faint and distant radio signals and the transmission of useful data across vast distances. The signals from such spacecraft may be only millionths or billionths of a single watt by the time they reach antennas on Earth, and can easily be lost in the random natural radio noise of space. Signals constructed using Golomb's methods, however, can be isolated and read.
A striking demonstration of the application of Golomb's principles came in 1961, with what became known as the Venus Radar Experiment. Golomb was the lead scientist of the project, which successfully bounced radar signals off another planet for the first time. As an added bonus, the experiment corrected and more precisely defined the astronomical unit (AU), a standard astronomical yardstick defined as the distance between Earth and the Sun and a crucial navigational consideration for future planetary missions. Later, an experiment proposed by Golomb based on his work developing an interplanetary ranging system was carried out with the Mariner 9 Mars probe in 1969, providing an ingenious confirmation of Einstein's General Relativity.
Because of their broad applicability, Golomb's concepts have become part of the standard vocabulary for mathematicians and engineers. "Golomb rulers" and "Golomb codes" have informed the development and design of spread frequency spectrum and data compression techniques for all varieties of digital communications, including the internet and cellphone networks we use daily. The transition from analog to digital communications would not have been possible without Golomb's contributions.
Those contributions extend beyond the merely practical or tangible. As an educator and mentor, Golomb has taught, trained, and inspired several generations of engineers and scientists, not only at JPL but at the University of Southern California, where he has been a professor since 1963, now as Distinguished Professor of Electrical Engineering and Mathematics and the Andrew and Erna Chair in Communications. He has authored many seminal papers and several books which have become standard texts in the field. His work on polyomino games and the theory behind them later helped to inspire the popular game Tetris. And his more lighthearted pursuits have included writing puzzle columns and creating games for various magazines including Scientific American.
Golomb's achievements have been formally recognized with various honors, including membership in the National Academy of Sciences and the National Academy of Engineering, and fellowship in the Institute of Electrical and Electronics Engineers (IEEE) and the American Academy of Arts and Sciences. Among many other awards, he is a recipient of the IEEE's Shannon Award and Hammond Medal, and was awarded the 2011 National Medal of Science by President Barack Obama.
For many years after electronic communications first came into existence, most engineers firmly believed that the technologies would always be inherently analog. Solomon Golomb has spent his career proving otherwise. As we settle into the 21st century, it's safe to say that the digital age, with all its convenience, efficiency, productivity, and connectivity is not about to disappear—thanks to its putative father, Solomon Golomb.
Information as of March 2016