# Robert Calderbank

- Charles S. Sydnor Professor of Computer Science
- Professor of Computer Science
- Professor of Electrical and Computer Engineering (Joint)
- Professor of Mathematics (Joint)

**External address:**140 Science Drive, 317 Gross Hall, Durham, NC 27708

**Internal office address:**Campus Box 90984, 140 Science Drive, Durham, NC 27708

**Phone:**(919) 613-7874

### Research Areas and Keywords

##### Algebra & Combinatorics

##### Analysis

##### Computational Mathematics

##### Number Theory

##### Physical Modeling

##### Probability

##### Signals, Images & Data

Robert Calderbank is Director of the Information Initiative at Duke University, where he is Professor of Electrical Engineering, Computer Science and Mathematics. He joined Duke in 2010, completed a 3 year term as Dean of Natural Sciences in August 2013, and also served as Interim Director of the Duke Initiative in Innovation and Entrepreneurship in 2012. Before joining Duke he was Professor of Electrical Engineering and Mathematics at Princeton University where he also directed the Program in Applied and Computational Mathematics.

Before joining Princeton University Dr. Calderbank was Vice President for Research at AT&T. As Vice President for Research he managed AT&T intellectual property, and he was responsible for licensing revenue. AT&T Labs was the first of a new type of research lab where masses of data generated by network services became a giant sandbox in which fundamental discoveries in information science became a source of commercial advantage

At Duke, Dr. Calderbank works with researchers from the Duke Center for Autism and Brain Development, developing information technology that is able to capture a full spectrum of behavior in very young children. By supporting more consistent and cost-effective early diagnosis, the team is increasing the opportunity for early interventions that have proven very effective.

At the start of his career at Bell Labs, Dr. Calderbank developed voiceband modem technology that was widely licensed and incorporated in over a billion devices. Voiceband means the signals are audible so these modems burped and squeaked as they connected to the internet. One of these products was the AT&T COMSPHERE^{®} modem which was the fastest modem in the world in 1994 – at 33.6kb/s!

Together with Peter Shor and colleagues at AT&T Labs Dr. Calderbank developed the group theoretic framework for quantum error correction. This framework changed the way physicists view quantum entanglement, and provided the foundation for fault tolerant quantum computation.

Dr. Calderbank has also developed technology that improves the speed and reliability of wireless communication by correlating signals across several transmit antennas. Invented in 1996, this *space-time coding* technology has been incorporated in a broad range of 3G, 4G and 5G wireless standards. He served on the Technical Advisory Board of Flarion Technologies a wireless infrastructure company founded by Rajiv Laroia and acquired by Qualcomm for $1B in 2008.

Dr. Calderbank is an IEEE Fellow and an AT&T Fellow, and he was elected to the National Academy of Engineering in 2005. He received the 2013 IEEE Hamming Medal for contributions to coding theory and communications and the 2015 Shannon Award.

Bremner, A., et al. “Two-weight ternary codes and the equation y2 = 4 × 3a + 13.” *Journal of Number Theory*, vol. 16, no. 2, Jan. 1983, pp. 212–34. *Scopus*, doi:10.1016/0022-314X(83)90042-2.
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Calderbank, R. “A Square Root Bound on the Minimum Weight in Quasi-Cyclic Codes.” *Ieee Transactions on Information Theory*, vol. 29, no. 3, Jan. 1983, pp. 332–37. *Scopus*, doi:10.1109/TIT.1983.1056673.
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Calderbank, R. “SQUARE ROOT BOUND ON THE MINIMUM WEIGHT IN QUASI-CYCLIC CODES..” *Ieee Transactions on Information Theory*, vol. IT-29, no. 3, 1983, pp. 332–37.

Calderbank, A. R., et al. “UPPER BOUNDS ON THE MINIMUM DISTANCE OF TRELLIS CODES..” *The Bell System Technical Journal*, vol. 62, no. 8 pt 1, 1983, pp. 2617–46.

Calderbank, A. R., and D. B. Wales. “A global code invariant under the Higman-Sims group.” *Journal of Algebra*, vol. 75, no. 1, Jan. 1982, pp. 233–60. *Scopus*, doi:10.1016/0021-8693(82)90073-4.
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Calderbank, R. “On uniformly packed [n, n-fc,4] codes over gf(Q) and a class of caps in ?g(k-l, q).” *Journal of the London Mathematical Society*, vol. s2-26, no. 2, Jan. 1982, pp. 365–84. *Scopus*, doi:10.1112/jlms/s2-26.2.365.
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Calderbank, R. “A Good Method of Combining Codes.” *Linear Algebra and Its Applications*, vol. 32, Jan. 1980, pp. 115–24. *Scopus*, doi:10.1016/0024-3795(80)90011-7.
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Calderbank, Robert, et al. *On block coherence of frames*.

Wu, Yiyue, et al. *The Value of Staying Current when Beamforming*.

Calderbank, Robert, et al. *Fusion Frames: Existence and Construction*.