Qualcomm R&D & Heterogeneous Networks — Growing Capacity via Topology

The first part of the talk presents an overview of the R&D activities at Qualcomm. The second part of the talk discusses wireless system design in the post-MIMO/OFDMA era. Homogeneous macro-cellular network capacity is approaching the theoretical limit through technology evolutions in multiple access, coding modulation and spatial processing. Our studies indicate that further substantial capacity growth could be achieve through embedding pico/femto/relay base-stations in a macro-cellular network. However, introduction of these mutually dissimilar base-station types on the same wireless channel challenges some of the established paradigms in cellular system design, and requires advanced interference coordination and other novel optimization techniques to realize the full potential of the diverse base-station types that are embedded in the macro-cellular systems. This talk highlights some of the problems that need to be solved in order to maximize the capacity and cell-edge performance of such heterogeneous systems, and highlights a few promising approaches that may be developed further in order to address these problems in an effective manner.

Tingfang Ji received his B.S. degree in electronic engineering from Tsinghua University, Beijing in 1995, his M.S and Ph.D degrees both in electrical engineering from the University of Toledo Ohio and the University of Michigan, Ann Arbor in 1997 and 2001, respectively. From 2001 to 2003 he was a member of the technical staff at Bell Laboratory Advanced Technology department, where he conducted research on 3G cellular networks and Ultra Wide Band. Since 2003, he has been with the Corporate R&D division of Qualcomm Inc, where he is currently a senior staff engineer and manager. From 2003 to 2007, he was one of the key technical contributors to the development of wideband OFDMA technologies which evolved into IEEE 802.20 and 3GPP2 UMB standards. Since 2007, he has been closely involved in the development and standardization of 3GPP LTE Advanced technologies. His research interests include coding and modulation, network MIMO, relay networks, mobility, and heterogeneous networks.