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Science and Technology Studies Commons

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Engineering

Selected Works

Professor Farzad Safaei

Selected Works

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Full-Text Articles in Science and Technology Studies

Order-4 Orthogonal Cooperative Communication In Space-Time-Frequency Coded Mb-Ofdm Uwb, Zixuan Lin, Le C. Tran, Farzad Safaei Jun 2013

Order-4 Orthogonal Cooperative Communication In Space-Time-Frequency Coded Mb-Ofdm Uwb, Zixuan Lin, Le C. Tran, Farzad Safaei

Professor Farzad Safaei

The combination of cooperative communication and Space-Time-Frequency-Codes (STFCs) has been recently proposed in the literature for Multiband OFDM Ultra-Wideband (MB-OFDM UWB) to improve the bit error performance, system capacity, data rate and wireless communications range. This paper proposes a cooperative communication design using Order-4 Orthogonal STFCs in MB-OFDM UWB systems, which is referred to as Order-4 Orthogonal Cooperative Communication Scheme (4-OCCS). It will be shown that 4-OCCS improves significantly the diversity and error performance of the MB-OFDM UWB system, compared to the conventional MB-OFDM UWB (without STFCs) as well as our Order-2 Orthogonal Cooperative Communication Scheme using Alamouti STFCs (2-OCCS) …


Double Space-Time Transmit Diversity For Very High Data Rate Mb-Ofdm Uwb Systems, Ngoc P. Le, Le C. Tran, Farzad Safaei Jun 2013

Double Space-Time Transmit Diversity For Very High Data Rate Mb-Ofdm Uwb Systems, Ngoc P. Le, Le C. Tran, Farzad Safaei

Professor Farzad Safaei

In this paper, we investigate a multiband-orthogonal frequency division multiplexing ultra-wideband (MB-OFDM UWB) system with very high data rates (VHDR) of several gigabits per second (Gbps). We propose a DSTTD-based VHDR MB-OFDM UWB system by incorporating a double space-time transmit diversity (DSTTD) scheme into the conventional MB-OFDM UWB system. At the receiver, an efficient soft-demapper that takes into consideration the noise enhancement due to a zero-forcing equalization is developed. Numerical simulations of the proposed system at a very high data rate of 2.Gbps over the IEEE 802.15.3a channel models are implemented. The simulation results show that this system could achieve …