Abstract:
Quasi-Orthogonal Space Time Block Code (QO-STBC) is a class of open-loop transmit diversity codes that offers better spectral efficiency than Orthogonal STBC (O-STBC) via higher code rate, and lower decoding complexity than Non-Orthogonal STBC via group-wise decoding. MDC-QO-STBCs (QO-STBC with minimum decoding complexity) are single-symbol-decodable as they require joint detection of only the real and imaginary parts of a complex symbol, hence they have the minimum decoding complexity among any QO-STBC (anything simpler will be an O-STBC which suffers lower code rate). In this talk, we will discuss the algebraic structure of MDC-QO-STBC, its optimum constellation rotation, code construction, antenna scalability performance, link to AOD (Amicable Orthogonal Design, which has been used to construct O-STBC) and hence maximum achievable code rates. We will also discuss how to achieve non-coherent transmit diversity using single-symbol-decodable differential space-time modulation (DSTM) schemes based on MDC-QO-STBC with joint modulation sets. If time permits, we will briefly present a graph-based methodology to search for QO-STBC with code rate > 1, and the resultant findings of new QO-STBCs with rate 5/4 and 4 for 4 transmit antennas.
Speaker' details:
Dr. Yong Liang Guan (M98-SM04) obtained his B.Eng. (Hon) degree from the National University of Singapore in 1991, and Ph.D degree from the Imperial College of London, UK, in 1997, both in electrical and electronic engineering. He joined the Nanyang Technological University (NTU) of Singapore in Nov. 1997, where he is currently an Associate Professor in the School of Electrical and Electronic Engineering, Program Director (Wireless Network) of the Positioning and Wireless Technology Centre, and Deputy Director of the Center of Information Security. His research interests include modulation and coding (space-time coding, Turbo coding, multi-carrier modulation, wideband CDMA, UWB signal processing), cross-layer optimization, channel modeling (UWB, multi-carrier, MIMO, power line, Markov channels) and digital watermarking for multimedia information security.
Dr. Guan has published over 100 papers in international journals and conferences. He has 1 patent granted and another filed, both in digital watermarking. He is the principal investigator to 6 past and current externally funded projects and 2 NTU-funded projects, with research focus ranging from UWB signal processing, turbo coding/decoding, MIMO-OFDM, to compressed video watermarking.
