Nambi Seshadri’s pioneering research and commercial intuitiveness have impacted multiple generations of mobile and wireless communications and have helped make technology more affordable for consumers. While at AT&T Shannon Labs, one of Seshadri’s key research initiatives was his work on transmission and coding techniques using multiple transmit antennas. This helped create a new field of wireless communications called space-time coding that improved the reliability of data transmission. An earlier version of this work that he did at AT&T Bell Labs, called delay diversity, was an important component of the 2G cellular time-division multiple access systems and has also impacted WiFi and LTE systems. His contributions to reliable transmission of compressed speech over mobile radio channels also influenced the development of 2G cellular systems. He also drove the adoption of adaptive modulation and hybrid automatic repeat request techniques (important for high performance in time varying channels) in to the Enhanced Data Rates for Global Evolution (EDGE) standards. These techniques have become core to robust transmission in 3G and 4G systems around the world. His work on list Viterbi decoding and applications for combined speech and channel decoding as well as data transmission systems have been applied to improve speech quality in 2G and 3G systems. Following his career at AT&T Bell Labs and AT&T Shannon Labs, Seshadri helped build Broadcom into a significant player in the wireless market. Here, he initiated or nurtured projects such as short-range wireless, WiFi modems in phones, cellular modems, GPS, near-field communications, and the multimedia chip set strategy that resulted in pioneering products such as the high-definition video camcorder and advanced megapixel camera phones. Through his leadership, the company was able to reduce prices while improving the performance of wireless chipsets. This system-on-chip integration of applications processing, graphics, haptics, WiFi, Bluetooth, camera, and 2G/3G/4G modems has impacted the industry by making smart phones much more affordable.
An IEEE Fellow and member of the U.S. National Academy of Engineering, Seshadri is a professor of electrical and computer engineering at the University of California, San Diego, San Diego, CA and consulting CTO at Quantenna Communications, San Jose, CA, USA, in addition to serving as an advisor for several startups.
Continually expanding the frontiers of digital communications, H. Vincent Poor’s development of advanced signal processing methods for wireless networks not only eased the early transition to digital mobile networks but also plays a key role in advancing today’s communications systems in which the need for new capacity must overcome the challenges of bandwidth limitations. During the 1980s and early 1990s, Poor tackled the obstacles of interference and insufficient capacity with innovations in interference mitigation that allowed wireless receivers to operate effectively in areas limited by interference. His fundamental work on multiuser detection includes the concept of turbo multiuser detection, which introduced the principle of cross-layer interaction in wireless networks; adaptive methods, which allow for interference suppression while having only limited knowledge of the structure of the interference; and space-time methods applicable to the multiple antenna systems that have been integral to the success of modern high-capacity networks. These contributions have impacted modern mobile technology, satellite systems, and local-area networks, coinciding with the rise of widespread consumer wireless communications and providing key methodologies for addressing the explosive demand for capacity. Poor’s recent work has focused on communications problems arising in emerging smart-grid and social networking applications, including the development of privacy-preserving communication techniques. Poor has also introduced new approaches based on game theory for modeling the behavior of wireless networks of autonomous terminals.
An IEEE Life Fellow and member of the U.S. National Academies of Engineering and Sciences, Poor is the Michael Henry Strater University Professor of Electrical Engineering at Princeton University, Princeton, NJ, USA.
The third-generation (3G) cellular technology enabled by the vision and leadership of Roberto Padovani is transforming lives around the word by supporting voice and wireless Internet access via mobile devices to over 3 billion people. Padovani provided key leadership in developing and commercializing code-division-multiple-access (CDMA) technology during the 1980s and 1990s to substantially increase circuit-switched voice capacity and enable efficient high-data-rate (HDR) packet-switched communications. His work has formed the basis for all 3G cellular systems and has also influenced fourth-generation long-term evolution (LTE) systems. Padovani later adapted CDMA technology, which was originally heavily tuned for voice services, to support data services. To overcome the challenges of asymmetry in data traffic in the up- and downlinks and the bursty nature of data, Padovani developed innovations including the scheduling of high and low rate users, variable modulation and code rate, and power control strategies for more efficient Internet data transfer, resulting in the HDR technology. He realized early on that, for packet data, symmetric performance across uplink and downlink and equal grade of service across users could be relaxed to improve total system throughput, in contrast to voice designs that focused on giving all users equal service in all conditions. Slow to be accepted by operators who were primarily concerned only with voice capacity, the demand for HDR communications grew as mobile phones began to support e-mail and Internet services. HDR evolved into the 1X EVDO system, which paved the way for high-speed data services on 3G systems. The availability of packet-switched Internet access made possible by Padovani’s innovations has impacted business, safety, entertainment, navigation, social networking, education, and health in developed and especially developing countries around the world.
An IEEE Fellow and member of the U.S. National Academy of Engineering, Padovani is executive vice president and fellow with Qualcomm Technologies, San Diego, CA, USA.
The mathematical models developed by Frank Kelly have enabled communications networks, including the Internet, to handle ever-increasing amounts of data transmission, while maintaining quality of service, by overcoming challenges including network congestion. He has provided the mathematical foundations for a scientific understanding of fundamentally important network phenomena, including distributed congestion control in packet-switched networks, blocking, and dynamic routing in circuit-switched telephone networks. Dr. Kelly’s landmark work on rate control during the 1990s developed the equations responsible for governing traffic on the Internet and transformed the field. He was one of the first to provide economic insights on control problems in telecommunication networks, leading to his development of the “proportional fairness” concept. This spurred new research on rate control for the Internet and spawned worldwide activity on analysis of control schemes and congestion pricing, demonstrating how rate control of the Internet could be placed in a rigorous mathematical framework. Proportional fairness is now a central concept in analyzing resource allocation in networks. Dr. Kelly’s work opened the way for model-based development of the Traffic Control Protocol (TCP), with practically all forms of congestion control today incorporating Dr. Kelly’s equations. His work with colleagues on dynamic alternative routing (DAR) during the 1980s provided a call-routing procedure in telephone networks for choosing alternate call paths when the primary path between a source and destination was blocked. Key to the success of DAR was the ability to determine the alternate paths online and in real time with information based on where and when the call was initiated. DAR’s success led to implementation in the British Telecom network and has been widely influential.
A Foreign Member of the US National Academy of Engineering and Fellow of the UK Royal Society, Dr. Kelly is currently professor of the mathematics of systems at the University of Cambridge, Cambridgeshire, UK.
For more than three decades, Dariush Divsalar’s innovative contributions to information theory and communications technology have provided advancements leading to more reliable and efficient near-capacity transmission and reception of data for wireless networks and deep space communications. Dr. Divsalar’s channel coding innovations have led to state-of-the art technology and represent the most advanced high-performance coding schemes standardized for deep space communications today. Channel codes are used to protect data transmission and storage in the presence of noise or errors. Perhaps best known for his work on understanding turbo codes, which were the first practical codes to closely approach channel capacity, Dr. Divsalar optimized and standardized turbo codes for deep-space applications. He also co-invented a new class of protograph-based low-density parity-check (LDPC) codes for efficient information transfer over noisy channels. Known as Accumulate Repeat Accumulate codes, the technique is based on accumulators, puncturing, and a precoder to further improve performance. These new codes are themselves an enhanced version of Repeat Accumulate codes previously co-invented by Dr. Divsalar. These new protograph-based LDPC codes have become Consultative Committee for Space Data Systems (CCSDS) international standards and are being used in NASA missions. Dr. Divsalar has also contributed significantly to bandwidth-efficient coded modulation, with work that paved the way to trellis coded modulation design for wireless fading channels that became the basis of the modern approach of bit-interleaved coded modulation. This is an integral component of today’s WiFi and 4G wireless systems. He also developed the parallel partial interference cancellation scheme for multiuser systems, analyzed it, and showed its superiority in improving code division multiple access (CDMA), which was an important building block of multiple access communications systems. Dr. Divsalar’s latest discoveries are impacting the use of wireless, deep space, and free-space optical communications for high-speed data links.
An IEEE Life Fellow and recipient of the NASA Exceptional Engineering Achievement Medal (1996), Dr. Divsalar is currently a senior research scientist with the Jet Propulsion Laboratory, Pasadena, CA, USA.
The insight of Andrew R. Chraplyvy and Robert W. Tkach into understanding and overcoming the limitations of nonlinearities in optical fiber communications systems revolutionized the telecommunications industry by providing the speed and capacity needed for today’s demanding data transmission. Optical communications involves transmitting information as pulses of light that are converted into words, images, and sounds upon reception. When using multiple wavelengths on a single optical fiber, nonlinearities can occur that garble the pulses of data. Working at Bell Labs, Drs. Chraplyvy and Tkach recognized that these nonlinear effects limit the capacity and transmission distances of optical communication systems. The pair developed the dispersion management concept to combat the effects of these optical nonlinearities. The success of their work has provided the high-capacity, high-speed transmission systems that serve as the backbone of the Internet and modern telecommunications systems. Drs. Chraplyvy and Tkach also developed a new type of optical fiber known as non-zero dispersion shifted fiber. This was adopted by AT&T and later Lucent Technologies as TrueWave Fiber and has become an industry standard. Over 70 million kilometers of this fiber have been installed worldwide and are a key component of most transoceanic lightwave submarine cable systems. The pair’s accomplishments have enabled wavelength division multiplexing fiber transmission systems with capacities beyond 1 Tb/s per fiber, representing a 100-fold increase in transmission capacity in a 10-year period.
Drs. Chraplyvy and Tkach are both IEEE Fellows and Fellows of the Optical Society of America. They are both members of the U.S. National Academy of Engineering. Their many honors include the Thomas Alva Edison Patent Award (1999), the IEEE/OSA John Tyndall Award (2003 and 2008, respectively) and the Marconi International Fellowship Award (2009). Dr. Chraplyvy is Optical Technologies Research Vice President, and Dr. Tkach is Director of the Advanced Photonics Research Department at Bell Labs, Alcatel-Lucent, Holmdel, NJ, USA.
Leonard Kleinrock is considered one of the fathers of the Internet for his development of packet-switching networks, providing the theory upon which the Internet exists today. Dr. Kleinrock developed the mathematical theory of packet-switching networks during the early 1960s as a graduate student at the Massachusetts Institute of Technology to handle the burst-like nature of computer data transmission and its resulting inefficiencies. Packet switching involves packaging data into specially formatted units, or packets, that identify the sender and the intended recipient and enables shared use through routing and queuing of the data. Dr. Kleinrock transferred his theory to practical deployment at the University of California, Los Angeles (UCLA) through the U.S. Defense Advanced Research Project Agency’s (DARPA) predecessor of the Internet, known as ARPANET. His host computer became the very first node of ARPANET in September 1969, and he supervised the transmission of the first message ever sent over the Internet in October 1969. His group evaluated ARPANET as it grew during the 1970s, and he proved that packet-switched networks could provide highly efficient data communications and would not fail in a full-scale deployment. This was instrumental in persuading the U.S. Government to fund Internet development. During the 1970s, Dr. Kleinrock’s pioneering work on packet radio methods provided the foundation for today’s wireless cellular communications, WiFi, and 3G/4G mobile computing technologies. Today’s emerging “cloud computing” platforms, where services are provided on-demand much like traditional utilities, were predicted by Dr. Kleinrock back in 1969.
An IEEE Life Fellow, Dr. Kleinrock is currently a Distinguished Professor of Computer Science at UCLA, where has worked since 1963.
Arogyaswami J. Paulraj’s development of multiple input-multiple output (MIMO) antenna technology for wireless communications has revolutionized both local area and mobile broadband communications, enabling high-speed access to multimedia services. Employing multiple antennas at both the transmit and the receive stations, the success of MIMO is its ability to provide both higher data rates and wider coverage areas. Dr. Paulraj first developed the idea of MIMO in 1992 while at Stanford University. Using the spatial multiplexing concept that exploits MIMO antennas, he demonstrated that spectral efficiency could be improved by transmitting independent data streams from each transmit antenna and then exploiting the distinct spatial signatures of each stream at the receive antennas to separate them. He was issued a patent for the MIMO concept in 1994, but he faced skepticism from industry and funding sources. However, he persisted and held annual workshops at Stanford on the technology that eventually helped interest in MIMO take hold in the late 1990s. Dr. Paulraj founded Iospan Wireless Inc. in 1998 as the first company to incorporate MIMO technology in a commercial system. The lessons learned at Iospan gave the wireless industry confidence to incorporate MIMO into emerging wireless standards. Iospan’s technology underpins today’s 4G wireless systems. Intel Corp. acquired part of Iospan in 2003 to help launch its own push into wireless broadband, further establishing the importance of Dr. Paulraj’s MIMO concept.
An IEEE Fellow, Dr. Paulraj is a Professor Emeritus at Stanford University, Calif. and a senior advisor to Broadcom Corp., Irvine, Calif.
Robert J. McEliece is best known for his many seminal contributions to the theory and implementation of algebraic error-correcting codes. His numerous research articles have been invaluable to the understanding of a wide range of problems in information theory and coding. Dr. McEliece was one of the first researchers to study convolutional codes, which became a staple of channel coding for deep-space communications systems, and of notable importance was his work on NASA?s Galileo mission to Jupiter. When the spacecraft?s high-gain antenna failed to deploy, threatening the ability to transmit photos and data from Jupiter, Dr. McEliece was an important member of the team that reprogrammed the on-board convolutional encoder in a way that saved most of the data.
His other achievements include the much-celebrated ?McEliece, Rodmich, Rumsey, Welch Bound.? The MRRW Bound is the best known upper bound on the tradeoff between rate and minimum distance of the best binary codes.
He also created the McEliece Theorem, which identifies the largest power of p that divides all the weights in a p-ary cyclic code, and which contains the Ax divisibility theorem as a special case, considered to be one of the deepest mathematical results to come out of coding theory.
Dr. McEliece has contributed to the design of error-correction telecommunication systems for NASA/JPL spacecraft and for mass-market data storage systems (flash memories and disks) for Sony consumer electronics. An IEEE Life Fellow, Dr. McEliece is the Allen E. Puckett Professor and Professor of Electrical Engineering Emeritus at the California Institute of Technology, Pasadena, and is also a consultant to the NASA Jet Propulsion Laboratory, Pasadena.
Gerard J. Foschini, distinguished inventor at Bell Laboratories, Alcatel-Lucent, has made key contributions that have changed wireless communications. Dr. Foschini discovered how, using multiple antennas, wireless signals could be expressed across time and space for maximally efficient spectrum usage. His research has influenced several emerging wireless communications technologies including Multiple Input Multiple Output (MIMO), IEEE WiFi (802.11n) and WiMAX (802.16e) wireless data communication standards as well impacting discussions on 4G cellular standards worldwide (3GPP and 3GPP2).
A Fellow of Bell Labs where he joined in 1961 and an IEEE Fellow, Dr. Foschini has authored more than 100 published works and holds 14 patents related to communications technology. His work has been one of the most widely cited in technical journals and other publications, earning him the designation of “One of the most highly cited scientists” by the Institute of Scientific Information. He has previously taught at Princeton University, in Princeton, N.J. and is currently on the Graduate Electrical Engineering Faculty of Rutgers University, Piscataway, N.J. He has received numerous awards and honors, including the IEEE Eric E. Sumner Award and the Patent Award from the Research and Development Council of New Jersey. Dr. Foschini holds a bachelor’s from the New Jersey Institute of Technology, a masters from New York University, both in electrical engineering, and a doctorate in mathematics from Stevens Institute of Technology, Hoboken, N.J.
Norman Abramson is a pioneer in the field of wireless and local area networking. While at the University of Hawaii, he led efforts that gave rise to the construction and operation of the ALOHAnet, the first wireless packet network, and to the development of the theory of random access ALOHA channels. ALOHA channels have yielded significant advancements within wireless and local area networking, with versions still in use today in all major mobile telephone and wireless data standards. This influential work also developed the core concepts found today in Ethernet.
Dr. Abramson previously served as chair of the University of Hawaii?s information and computer sciences department and director of the ALOHA System research project. Dr. Abramson is a founder of ALOHA Networks, Inc and of SkyWare, Inc., both wireless communications companies located in San Francisco.
Additionally, Dr. Abramson served as a consulting expert in communication systems, data networks and satellite networks for the International Telecommunication Union (Geneva), the United Nations Educational, Scientific and Cultural Organization (Paris) and the United Nations Development Programme (Jakarta).
An IEEE Life Fellow, he holds eight U.S. and international patents, and has published more than 50 technical papers. Dr. Abramson has a bachelor?s degree in physics from Harvard University, a master?s degree in physics from The University of California, Los Angeles, and a doctoral degree in electrical engineering from Stanford University, California. Dr. Abramson has received the IEEE Koji Kobayashi Computers and Communications Award, the Golden Jubilee Award sponsored by the IEEE Information Theory Society and the Eduard Rhein Foundation Technology Award.
John M. Wozencraft?s pioneering work on error-correcting codes provided one of the foundations for the design of reliable digital transmission systems over the past 50 years. Coding is an integral part of today?s nearly error-free communications systems, including deep-space communication, the Internet and next-generation mobile telephony.
Based on the notion of random coding, sequential decoding was the first error-correcting algorithm whereby arbitrarily-accurate fixed-data-rate communication could be attained over noisy transmission channels with reasonable computational complexity. This approach paved the way for other algorithms that ultimately revolutionized the communications industry. It was a critical conceptual milestone in the evolution of error-correction coding from abstract mathematics to today?s palette of computationally practical error-correction techniques.
Sequential decoding became the method of choice for the low signal-to-noise ratio environment of deep space communications. It was first chosen for the Pioneer 9 deep space mission and was NASA's standard coding system for deep space for nearly a decade.
An IEEE Life Fellow, Dr. Wozencraft is Professor Emeritus at the Massachusetts Institute of Technology in Cambridge. He co-authored the book, "Principles of Communication Engineering," which sparked a revolution in how communications engineers think about digital communication. It was widely recognized as the bible of communications theory for more than two decades.
As a university professor, corporate leader and consultant, Dr. Jim K. Omura has been responsible for the theoretical underpinning and application of several benchmark technologies for communications systems and data networks.
During his tenure as a professor of electrical engineering at University of California, Los Angeles, he co-authored the textbook "Principles of Digital Communications and Coding" with Andrew Viterbi and designed several communication systems emphasizing spread spectrum communications. He then co-founded Cylink Corporation in Sunnyvale, California, where he and his team developed the first commercial 1024-bit public key encryption chip used to secure large, commercial data networks. His designs for spread spectrum data radios formed the basis for the development of spread spectrum cordless telephones licensed for commercial applications and were precursors to today's widely used WiFi wireless-access radios.
Most recently, Dr. Omura has served as Technology Strategist for the Gordon and Betty Moore Foundation in San Francisco and as an advisor to several companies in the wireless communications industry.
An IEEE Fellow, Dr. Omura is former chairman of the San Francisco Section of the IEEE Information Theory Society (ITS), former secretary and a former member of the board of governors of the IEEE ITS. From 1973-75, he was editor of the IEEE Newsletter of the IEEE ITS. He is also a member of the U.S. National Academy of Engineering.
Joachim Hagenauer's open-minded approach to coding has resulted in several innovations with profound implications for communication systems. He pioneered the development of the soft-in/soft-out principle, which prevented the loss of valuable information that came with forcing hard decisions during the decoding process. This principle touched off research around the globe and yielded in the implementation of fast (Gigabit per second) analog VLSI decoders working only with soft bits.
Professor Hagenauer's work paved the way for the development of turbo coding and caused a paradigm shift in the way channel coding is applied to digital communication and storage problems. His contributions also can be seen in such digital receiver design applications as third generation mobile transmission systems, satellite transmission and more.
He published several key papers on the new decoding paradigm, thereby contributing significantly to a better understanding of the emerging coding and decoding systems.
After serving as an assistant professor at Darmstadt University, Professor Hagenauer held a postdoctoral fellowship at the IBM T.J. Watson Research Center in Yorktown Heights, N.Y. Since 1977, he has been with the German Aerospace Center DLR in Oberpfaffenhofen, where he became director of the Institute for Communication Technology in 1990. Since 1993, he has chaired the Communications Technology department at the University of Technology in Munich, Germany.
An IEEE Fellow, Professor Hagenauer has served on the board of the IEEE Information Theory Society as its president in 2001. He has been honored with the Erich Regener and Otto Lilienthal Prizes of the German Aerospace Association, the Armstrong Award of the IEEE Communications Society, and a Best Teacher Award from the Students Union of the Munich University of Technology. He was recently elected to the Bavarian Academy of Science.
Since joining Sumitomo Electric Industries, Ltd., in 1953, Dr. Tsuneo Nakahara has been a major force in the conception, design and manufacturing of optical fiber and cables. Under his guidance, the company developed the vapor phase axial deposition optical fiber manufacturing technology, which has become the standard in Japan and is one of the top three fiber manufacturing processes worldwide. His team also designed extremely low-loss optical fiber with pure silica as the core and fluorine in the clad. This technology was widely used for undersea long distance cables. He has also been a leader of important research into multi-count optical fiber, leaky coaxial cable, milliwave and beam waveguide, and more.
An IEEE Life Fellow, he has served in many capacities, including Region 10 director, secretary of the Board of Directors and Foundation Board director. Outside the IEEE, he also serves as vice president of the Engineering Academy of Japan, foreign associate of the U.S. National Academy of Engineering and president of Japan?s New Technology Association. Executive advisor to the CEO of Sumitomo Electric Industries, Ltd., Dr. Nakahara holds nearly 300 patents in the United States and Japan combined, and has published over 100 papers. He has received numerous awards, including an IEEE Millennium Medal, the Okabe Memorial Award from the Institute of Electronics and Communications Engineers of Japan, and the Blue Ribbon Medal from the Emperor of Japan.