Master of Convergence

Digital visionary Tadahiro Sekimoto championed the integration of computers and communications

9 min read

The 2004 IEEE Medal of Honor winner, former NEC Corp. chairman , has had a career that for sheer drama and accomplishment has few counterparts in industrial history. As a researcher and research manager in the 1950s and 1960s, he pioneered the use of time-division multiple access and other digital technologies that revolutionized satellite communications, as well as digital compression techniques that evolved into today's digital video.

After rocketing through the NEC management ranks in the 1970s, he became president in 1980 and chairman in 1994, overseeing the company in an era when revenues swelled from US $4.7 billion to $40.3 billion by 1998. Along the way, the Queen of the United Kingdom made him an Honorary Knight Commander of the Order of the British Empire, and France inducted him into L'Ordre National de la Légion d'Honneur.

Then, to quell a crisis that threatened the company in 1998, he gave up his position as chairman, showing he was as bold an executive as he was a technical innovator.

IT'S BEEN A LONG, EXHILARATING TRIP from the local restaurant Sekimoto's parents operated in Kobe, Japan, to the spacious Tokyo office he now inhabits as chairman of the Institute for International Socio-Economic Studies, a technology-oriented think tank. Kobe, a picturesque city in western Japan, is known for its beef and sake, not its engineers. But as a middle school student, Sekimoto got better grades in science than in any other subject, so he entered college bent on studying physics and winning a Nobel Prize.

One of his housemates, however, was Kazuhiko Nishijima, who would become one of the great theoretical physicists of his generation. ”Whenever we had homework, Nishijima would just come up instantly with a solution, while I had a hard time,” Sekimoto says. ”I would sweat over the work for hours before I came up with a solution. I realized that people are born with different aptitudes.”

”Meeting him made me discover that I did not have an aptitude for theoretical physics, so I had to think about what else I could do,” he recalls. ”Had I not met him, I would probably have gone on to become a professor or a scholar, but in that case my career would have advanced at the speed of a tortoise.”

Sekimoto changed his major from theoretical to experimental physics and, after getting his bachelor's degree in 1948, went straight to NEC's research laboratories in Tokyo. His first assignment was to design a new telephone set. For a while, he toiled away at small assignments, a young peasant in the feudalistic, seniority-based Japanese corporate research establishment. ”Whatever my boss ordered me to do, I would say, ’Yes, sir.'”

One early project was the joint development with Kyoto University of a voice-activated typewriter. Though Sekimoto was directly involved with this effort only for a short time, the project continues to date. And it foreshadowed his later advocacy of voice-recognition technology while at NEC.

The turning point of his career was a pulse code modulation (PCM) research project contracted from the Self-Defense Forces of Japan in 1957. PCM is now a standard means of converting analog signals, especially audio, into digital information. The magnitude of the analog signal is sampled frequently, typically thousands of times a second, and the resulting samples are translated into binary digits—digitized, in other words. Sekimoto's basic interest was, first of all, whether PCM technology could sustain a viable quality of communications, and second, how changes in the bit rate affected the quality of the transmitted and received signals.

Sekimoto was immediately infatuated with the technology, which had not found much commercial success after its invention in the late 1930s. He was intrigued by PCM's ability to get messages through noise and became convinced he could use it to transmit high-quality signals over long distances, via repeaters.

While his company supported his work on this project, allowing his team to grow from five to 10 members, his superior at the laboratory gave him a piece of friendly advice: don't become too absorbed in this PCM technology, because it has no future. Indeed, most engineers in those days were skeptical about the viability of the new technology. Sekimoto thought otherwise, but he did not argue, just quietly continued his work.

”Typical,” says Michio Naruto, chairman of Fujitsu Ltd.'s Research Institute, in Tokyo. (Fujitsu is a longtime competitor of NEC.) ”He is stubborn. He'll just say the same thing, year after year. You'll disagree, but next year he'll say the same thing; he won't change.”

Sekimoto later came up with this maxim to respond to such situations: ”Majority is for today, minority is for tomorrow.”

Sekimoto's involvement in PCM led to another life-changing encounter. In 1965, Kokusai Denshin Denwa Co. (now KDDI Corp.), the Japanese international telecommunications carrier based in Tokyo, nominated him for a one-year post in the laboratories of the newly formed Communications Satellite Corp. (Comsat) in Washington, D.C., now part of Lockheed Martin Corp. Comsat was then part of Intelsat, the international satellite-communications consortium. Asked if he would like to apply for the job, Sekimoto worried that his then-rudimentary English wouldn't pass muster. Still, he decided to go for an interview.

The Comsat people, however, were so impressed by his résumé and research papers on PCM that they waived the interview and immediately offered him a post as a department manager. Though still unsure about his English, he decided to take the job.

”Chance,” he says, ”is something you have to grasp with commitment, suppressing a feeling of uneasiness.”

O. Gene Gabbard, now a private investor and venture capitalist who in the 1990s was executive vice president and chief financial officer of MCI Communications Corp., was the first engineer to join Sekimoto's group at Comsat, just 10 days after Sekimoto had arrived as department head of modulation technique. ”His English was pretty poor, but he could communicate anyway,” Gabbard recalls. ”In our first conversation, we gestured, drew diagrams, and chose words that were easily understood. Still, I instantly liked and respected this man....I recognized immediately that he was a visionary.”

One of the key innovations of that Comsat group was a practical version of time-division multiple access (TDMA), a multiplexing scheme now used everywhere in international telephony, as well as in the Global System for Mobile Communications (GSM) cellphone system. The concept was not brand new: basically, TDMA takes a communications channel—a piece of radio bandwidth, say—and turns it into many channels by assigning different time slots to different channels. Before the Comsat group started working on the problem, researchers had studied time-division concepts for military-satellite communications, but had not yet applied it to commercial satellites.

Traditionally, the transponders on communications satellites were shared by simply giving each user a separate frequency. The scheme was fine for high-volume users, who could make use of all that transmission capacity, but was inefficient for medium- and low-volume users, who couldn't. A method was needed to let users share transponders and thereby achieve high overall efficiency. TDMA filled the bill perfectly: with computer controls, it would allow capacity to be adjusted dynamically, making the system extremely flexible and efficient.

There were challenges, of course, and some of the toughest revolved around the burst-mode communications that the system would employ. In practice, the data coming from an individual earth station would be sent as a burst of high-speed data that would have to be interleaved with the bursts from many other stations. To prevent any overlapping of all those bursts at the satellite, engineers put so-called guard times in between bursts from different stations; the fundamental design challenge is to synchronize the transmissions so accurately that those guard times are for all intents and purposes insignificant.

The timing challenge was huge enough to seem impossible. To deal with it, Sekimoto tapped Gabbard, who worked with a team including John G. Puente and Winfried Shrempp. The group plunged in, starting off with heavy mathematical analysis and ultimately tackling the problem by breaking new ground in special-purpose circuits (called phase-locked loops) that synchronize signals by locking them in phase and frequency.

About six months later, Sekimoto's group, which had grown to four engineers and three technicians, was well along in the implementation of the world's first experimental satellite time-division system, which they called MATE. It was only later that they coined the term time-division multiple access (whose acronym, Sekimoto confides, he never did like). In August 1966, the group successfully used the technology to allow multiple simultaneous users to share a satellite transponder, and Sekimoto, Gabbard, Puente, and Shrempp were issued patents for their methods of burst synchronization, timing recovery, and the overall TDMA scheme.

Sekimoto's one-year assignment at Comsat stretched to two, and he began working on the digital encoding and compression of TV signals, a project called DITEC, for digital television compression system. Such technology could also expand to three, from one, the number of television channels that could share a satellite transponder. Compression of video signals had been done before, but this project was the first to do all the compression, encoding, transmission, and decoding fully digitally. For this work Sekimoto is sometimes identified as the grandfather of MPEG, the ubiquitous digital compression standards developed by the Moving Picture Experts Group, used today to compactly store music, video, and other media.

SEKIMOTO LEFT COMSAT to return to NEC in 1967, before the digital video compression work was completed, but he pursued it within NEC. In the early 1970s, he was finally able to demonstrate a working system based on NEC's own technology to an assessment team from the U.S. broadcasting industry.

He returned to NEC as a research advisor, but rapidly climbed the management ranks. From general manager of the Transmission Division in 1972, he moved to senior vice president in charge of communications business in 1977, executive vice president in charge of domestic sales in 1978, and president of NEC Corp. in 1980.

During these years, Sekimoto developed an international reputation as an astute businessman. ”He was a pioneer in understanding [Western and Japanese] cultures, a pioneer in bringing Japan into the world business community,” says Tsuneo Nakahara, former vice chairman and now advisor to the CEO of Sumitomo Electric Industries Ltd. in Osaka.

Throughout his career climb, Sekimoto was the company's leading evangelist for what was, at the time, a revolutionary concept: ”C&C,” or the integration of computers and communications. The term refers to a world in which all communications are digital and all computers communicate within it. It was for his dedication to this concept, as well as for his technical achievements, that he was awarded this year's IEEE Medal of Honor.

As president, Sekimoto was willing to put his career on the line. In 1985, NEC won a $316 million contract to build a BS-3 broadcast satellite for the National Space Development Agency of Japan (now the Japan Aerospace Exploration Agency). After two such projects had relied on non-Japanese technology and failed, in 1977 and 1984, Sekimoto won the argument that this third project should be an all-Japanese affair. Susumu Kitazume, who led the project at NEC, recalls Sekimoto telling him that ”if NEC is not able to do this successfully with domestic technology, he would [commit] hara-kiri.”

”I asked whether or not, as the person responsible, I would then be saved?” Kitazume recalls. ”'No,' Sekimoto replied, ’you would be guillotined'”—the dishonorable way out. Had the effort not been successful, Kitazume believes, Sekimoto would have left NEC.

His management skills were put to the test when a scandal erupted at NEC in late September 1998. It ultimately resulted in the arrests of over a dozen officials of an NEC affiliate, Toyo Communication Equipment Co.; a subsidiary, Nico Electronics Co.; and finally of NEC itself. The central allegations were that NEC had overcharged the Japan Defense Agency for contracts.

By early October, 38 of Japan's 47 prefectural governments had decided to exclude NEC from bidding on contracts—a potentially harsh blow to the company, which at the time counted on public-sector contracts for about 10 percent of its revenues.

And Sekimoto decided what he had to do.

”There is a legend in Japan,” he explains in an interview at his Tokyo office. ”Prince Yamatotakeru was attempting to sail across Tokyo Bay, to travel from Tokyo to Chiba. He encountered a strong wind and rough waves, and the boat began to sink. His wife, Princess Ototachibana, feared for his life. So she threw herself into the bay, in order to subdue the waves.”

”That is what I decided to do,” he says, gazing intently at his interviewer. ”To throw myself into the water.”

He announced his resignation on 23 October, and the waters indeed calmed. The company's stock improved, and business slowly returned to normal.

Sekimoto might have faded quietly from the public eye if not for the support of the many allies he has made over the years. In the flood of mail he got around the time of his resignation was a letter that came in from an old friend dated 24 October 1998, the day after he stepped down. ”In these difficult times,” it begins, ”after the courageous decision you took yesterday, I want to express again my personal feelings of respect and friendship. Yours sincerely, Jacques.” That's Jacques as in Chirac, the current president of France.

”He was really tough in that unhappy time,” says Fujitsu's Naruto. ”Everybody respected him for that.”

Sekimoto's sacrifice is all the more remarkable when considered in context of the simmering business climate of the late 1990s, which had turned more than a few tech company CEOs into unbound autocrats. Today his honorable move seems even more poignant, a sharp counterpoint to the wave of tech company scandals that have been offering a seemingly limitless supply of anecdotes about how greedy some top executives became, particularly in the United States, during the heady years of the tech bubble.

EVER THE VISIONARY, Sekimoto uses his influence today to organize international joint research and symposiums to address big, thorny world security issues and information technology-related challenges, such as the digital divide. His platform is the Institute for International Socio-Economic Studies, a wholly owned subsidiary of NEC. Established in July 2000, the institute has worked in partnership with the Brookings Institution, Washington, D.C.; the China Institute of Contemporary International Relations, Beijing; and the Gorbachev Foundation, Moscow.

Last year, it hosted Globalization Forum 2003 in Okinawa, attended by former Soviet Union President Mikhail Gorbachev, former Prime Minister Mahathir bin Mohamad of Malaysia, and other distinguished speakers from China, Japan, Korea, and the United States. Sekimoto also serves as the volunteer president of Channel J, an Internet TV company that disseminates Japan-related information, sits on the board of trustees for two major universities in Japan, and is on the board of directors of Thomson SA, in Boulogne, France.

He remains boundlessly enthusiastic about the ability of information technology to mitigate strife. His technological insight ranges far and wide, from the potential of the microscopic creatures called nematodes as computer memories to future band-compression methods that will allow videoconferencing over standard phone lines.

”He got out of one world and found another,” says Naruto. ”Because, fundamentally, he is an optimistic man.”

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