Communications pioneer Andrew J.Viterbi — who in 1962 earned one of the first doctorates in electrical engineering granted at the University of Southern California — has forever changed how people everywhere connect and communicate, whether from across a crowded city, between nations or from the infinite reaches of space.
Born into an analog world, this visionary thinker opened the doors to the digital age with the Viterbi Algorithm, a groundbreaking mathematical formula for eliminating signal interference. Today, the Viterbi Algorithm is used in all four international standards for digital cellular telephones, as well as in data terminals, digital satellite broadcast receivers and deep space telemetry.
Dr.Viterbi’s lifelong interest in communications began as a child, when his family fled Italy for America in 1939 to escape the persecution of Jews. Long absences from family members instilled a desire to find ways of communicating across political and geographical borders.
The Viterbi family first settled in New York, then Boston. He entered the Massachusetts Institute of Technology (MIT) in 1952, studying electronics and communications theory under such renowned scholars as Norbert Wiener, Claude Shannon, Bruno Rossi and Roberto Fano. In 1956, he met Erna Finci, married and started a family.
In 1957, the Cold War was underway. In October of that year, the Soviets launched Sputnik, the world’s first artificial satellite, and the space race was on.
The new MIT grad and his family moved to California, home to defense industry giants. He went to work at the California Institute of Technology’s Jet Propulsion Laboratory, then a center for communications and satellite control systems, which soon became part of a new National Aeronautics and Space Administration. There, he specialized in the communications technology of “spread spectrum” systems on a team that designed the telemetry equipment for the first successful U.S. satellite, Explorer 1. Faced with a challenge to process and transmit information packets from space as accurately and quickly as possible, the team confronted two problems: the satellite’s weak signal, caused by its long journey, and frequency changes created by rapid orbits.
From this work, Dr.Viterbi developed the topic for his Ph.D. dissertation at USC: error correcting codes.
Dr. Viterbi’s love of new ideas in information theory led him first into an academic career. In 1963, he joined the UCLA faculty, teaching courses in digital communications and information theory. However, he found that the algorithms needed to decipher convolutional codes — those used to improve the performance of radios and satellite links — were too complex and difficult to explain to students. His solution: create a brand new algorithm.
At the time, only a handful of computers in the world could perform the millions of operations required by his revolutionary algorithm. A computer capable of doing the calculations rapidly would have demanded the energy of a particle accelerator. However, time would eventually catch up with his vision.
Dr. Viterbi’s first internationally regarded book, Principles of Coherent Communications, appeared in 1966. A second, Principles of Digital Communications and Coding, followed in 1973. During this time, he remained dedicated to his career in the UCLA School of Engineering and Applied Science, conducting fundamental research in digital communications theory and publishing his findings in leading journals.
Visionary ideas seemed to feed his entrepreneurial appetite. In the spring of 1967, Dr.Viterbi met Irwin Jacobs at a telecommunications conference in California. Both men, and another of Dr. Viterbi’s colleagues, Leonard Kleinrock, shared an interest in forming a consulting group. With an investment of $1,500 — $500 from each man — the trio founded Linkabit. The company grew as it supplied software for government computers and performed simulations using the Viterbi Algorithm. By the 1970s, Linkabit began providing technology for defense communications satellites using very large antennas.
But the sophisticated transmission systems that emerged from the Viterbi Algorithm had reached their technological limits. Large amounts of data sent from communications satellites required highly efficient integrated circuits, far more sophisticated than those available at the time. Dr. Viterbi and his Linkabit associates came up with a breakthrough computer to accomplish the task and dubbed it a “microprocessor,” even though it was made up of many chips.
His renown grew as fast as the company. In 1975, Italy’s National Research Council awarded Dr. Viterbi one of its highest academic accolades, the Christopher Columbus Award.
In 1980, Linkabit merged with M/A-COM of Boston, remaining a separate division. It soon produced the VSAT (Very Small Aperture Terminal), the foundation for private satellite communications networks. In 1985, the VSAT division was sold to Hughes. The team of Viterbi and Jacobs had a new dream: together, they founded Qualcomm Corp. to develop and manufacture satellite communications and digital wireless telephones. When its doors opened in 1985, Dr. Viterbi was respected across the globe for his innovative ideas, as well as his uncanny ability to turn scientific discoveries into profitable enterprises.
In the 1990s, Dr. Viterbi again capitalized on his knowledge of spread spectrum technology. He and colleagues devised a new transmission technology for cellular phones — CDMA, for Code Division Multiple Access — which would provide simultaneous access to a multitude of users, with less interference and greater security for voice and data. According to his own calculations, the network could have a capacity 10 to 20 times greater than a traditional analog system.
Dr.Viterbi traveled the country as CDMA’s champion. Soon, flagship telecommunications companies, including Pacific Telesis, Motorola and AT&T, invested in the experimental technology. By 2000, there were 50 million CDMAsupported cell phones in the world, making CDMA the dominant cell phone standard. “It was a team effort, and I’m proud of the part I played,” he said later.
During this period, his enchantment with scholarship continued and Dr. Viterbi, who resided in La Jolla, continued to teach part-time at the University of California, San Diego. In 1994, he became a UCSD professor emeritus.
USC honored his inventive spirit in 1986 with the USC School of Engineering’s Outstanding Alumnus Award and again in 1996 with the Graduate School’s Diamond Jubilee Alumni Award. In 2000, he joined the USC Board of Trustees. Technion, the Israel Institute of Technology, invited him to become a distinguished visiting professor of electrical engineering.
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