In wireless communications, Raleigh developed a comprehensive and precise channel model that works with multiple antennas.[2] He employed the model to develop smart antenna signal processing techniques for rapid fading, multipath propagation, and frequency-division duplex environments.[3][4][5][6][7][8] As a result of this research, Raleigh found that multipath propagation could be exploited to greatly increase the capacity of wireless communications, enabling data rates competitive with wire-based networks.[9] In a paper prepared for the 1996 GLOBECOM conference in London, Raleigh presented the first rigorous mathematical proof that in the presence of naturally occurring multipath propagation multiple antennas may be used with special signal processing techniques to transmit multiple data streams at the same time on the same frequency, multiplying the information-carrying capacity (data rate) of wireless links.[10] From the time of Guglielmo Marconi, multipath propagation had always been treated as a problem to be overcome. The discovery that multipath can be harnessed to increase performance reversed a century of radio engineering practice.[1] In subsequent papers, Raleigh proposed a series of enhancements including the use of OFDM with MIMO and techniques for space-frequency coding, space-frequency-time channel estimation, and MIMO synchronization.[11][12][13][14][15] These inventions were incorporated into the LTE, WiMAX, 802.11n and 802.11ac standards.
Raleigh, V.K. Jones, and Michael Pollack founded Clarity Wireless in 1996. Clarity built a MIMO demonstration link and developed a related technology, vector orthogonal frequency-division multiplexing (V-OFDM). Clarity Wireless was acquired by Cisco Systems in 1998. Raleigh, Jones, and David Johnson founded Airgo Networks in 2001 to develop MIMO-OFDM chipsets for wireless LANs. Airgo Networks proposed MIMO as the best technology for meeting the performance goals of next-generation wireless LANs and contributed to the development of the IEEE 802.11n standard.[16] The company began shipping the world’s first MIMO-OFDM chipsets in 2003.[17] While at Airgo Networks, Raleigh was named to Network World’s “The 50 most powerful people in networking.”[18] Airgo Networks was purchased by Qualcomm in 2006.
Raleigh co-founded the technology innovation firm Headwater Research in late 2008 with Charles Giancarlo and became Lead Director of its board. Raleigh’s inventions at Headwater have spanned the wireless and medical device fields. The inventions include mobile device operating system enhancements, improvements to radiation beam therapy for cancer treatment, enhanced 3-D imaging systems for surgery, and cloud-based network function virtualization (NFV) advances.[19][20][21][22][23][24][25] Mobile OS controls and NFV are now widely deployed.[26]
In late 2009, Raleigh and Giancarlo spun out ItsOn to license and commercialize wireless technology, with Raleigh serving as the firm’s first CEO. ItsOn developed a cloud-based network function virtualization (NFV) platform that enables operators to implement intelligent, user context-aware policies including the ability for users to customize and manage their mobile phone services.[27] ItsOn’s service, called Zact, launched in May 2013.[28]
Raleigh holds more than 200 US patents[29] and over 150 international patents [30] in the fields of radio communications, medical devices, mobile device operating systems, radar systems, and mobile network function virtualization.
References
^ abBrodsky, Ira (2008). The History of Wireless: How Creative Minds Produced Technology for the Masses. Telescope Books. pp. 208–217. ISBN978-0-980-03830-9.
^Raleigh, Gregory; et al. (1994). Characterization of fast fading vector channels for multi-antenna communication systems. Conference Record of the Twenty-Eighth Asilomar Conference on Signals, Systems and Computers. Pacific Grove, CA 31 Oct-2 Nov 1994. pp. 853–857 vol. 2. doi:10.1109/ACSSC.1994.471582.
^Raleigh, Gregory; Paulraj, A. (1995). Time varying vector channel estimation for adaptive spatial equalization. Global Telecommunications Conference, 1995. Singapore November 14–16, 1995. pp. 218–224 vol. 1. doi:10.1109/GLOCOM.1995.500355.
^Raleigh, Gregory; Diggavi, S.N.; Jones, V.K.; Paulraj, A. (1995). A blind adaptive transmit antenna algorithm for wireless communication. IEEE International Conference on Communications, 1995. Seattle, WA June 18–22, 1995. pp. 1494–1499 vol. 3. doi:10.1109/ICC.1995.524451.
^Bores, T.; Raleigh, G.G.; Pollack, M.A. (1996). Adaptive space-time equalization for rapidly fading communication channels. IEEE Global Telecommunications Conference, 1996. London November 18–22, 1996. pp. 984–989 vol. 2. doi:10.1109/GLOCOM.1996.587578.
^Raleigh, G.G.; Jones, V.K. (1997). Adaptive antenna transmission for frequency duplex digital wireless communication. IEEE International Conference on Communications, 1997. Montreal June 8–12, 1997. pp. 641–646 vol. 2. doi:10.1109/ICC.1997.609909.
^Raleigh, G.G.; Bores, T. (November 1998). "Joint space-time parameter estimation for wireless communication channels". IEEE Transactions on Signal Processing. 46 (5): 1333–1343. Bibcode:1998ITSP...46.1333R. doi:10.1109/78.668795.
^Pati, Y.C.; Raleigh, G.G.; Paulraj, A. (1995). Estimation of co-channel FM signals with multitarget adaptive phase-locked loops and antenna arrays. IEEE International Conference on Acoustics, Speech, and Signal Processing, 1995. Detroit, MI May 9–12, 1995. pp. 1741–1744 vol. 3. doi:10.1109/ICASSP.1995.480034.
^Raleigh, G.G.; Jones, V.K. (1998). Multivariate modulation and coding for wireless communication. IEEE Global Telecommunications Conference, 1998. Sydney, Australia November 8–12, 1998. pp. 3261–3269 vol. 6. doi:10.1109/GLOCOM.1998.775808.
^Raleigh, G.G.; Jones, V.K. (November 1999). "Multivariate modulation and coding for wireless communication". IEEE Journal on Selected Areas in Communications. 17 (5): 851–866. doi:10.1109/49.768200.
^Raleigh, G.G.; Cioffi, J.M. (March 1998). "Spatio-temporal coding for wireless communication". IEEE Transactions on Communications. 46 (3): 357–366. doi:10.1109/26.662641.
^Jones, V.K.; Raleigh, G.G. (1998). Channel estimation for wireless OFDM systems. IEEE Global Telecommunications Conference, 1998. Sydney, Australia November 8–12, 1998. pp. 980–985 vol. 2. doi:10.1109/GLOCOM.1998.776875.
^Raleigh, G.G.; Cioffi, J.M. (1996). Spatio-temporal coding for wireless communications. IEEE Global Telecommunications Conference, 1996. London November 18–22, 1996. pp. 1809–1814 vol. 3. doi:10.1109/GLOCOM.1996.591950.
^O'Shea, Dan (28 February 2005). "Fast Forward". Connected Planet. Penton Media. Archived from the original on 16 November 2013. Retrieved 12 November 2013.