Set Partitioning to Construct Block Coded Modulation with the Presence of Spatial Modulation in MIMO Systems

In this paper, enhancing the BER performance of multiple-input multiple-output systems (MIMO) is considered by using Block Coded Spatial Modulation (BCSM). It is a combination of Block Coded Modulation (BCM) used set partitioning to formulate the code, and the spatial Modulation (SM) as a transmission technique of MIMO systems. To achieve this, the idea of MIMO communication systems, block coded modulation, set partitioning, multi stage decoding and spatial modulation have been combined. Matrix Laboratory (MATLAB) is used for the simulation and Bit Error Rate (BER) is obtained and verified. The simulation results for the combination of BCM with SM show that there is a significant improvement in BER performance compared to the classical SM techniques. It gives an approximately 5 dB enhancing of BER performance from the use of SM only, and about 3 dB enhancing from the use of coded information bits with SM

Power allocation strategies for distributed precoded multicell based systems

Multicell cooperation is a promising solution for cellular wireless systems to mitigate intercell interference, improve system fairness, and increase capacity. In this article, we propose power allocation techniques for the downlink of distributed, precoded, multicell cellular-based systems. The precoder is designed in two phases: first the intercell interference is removed by applying a set of distributed precoding vectors; then the system is further optimized through power allocation. Three centralized power allocation algorithms with per-BS power constraint and diferente complexity trade-offs are proposed: one optimal in terms of minimization of the instantaneous average bit error rate (BER), and two suboptimal. In this latter approach, the powers are computed in two phases. First, the powers are derived under total power constraint (TPC) and two criterions are considered, namely, minimization of the instantaneous average BER and minimization of the sum of inverse of signal-to-noise ratio. Then, the final powers are computed to satisfy the individual per-BS power constraint. The performance of the proposed schemes is evaluated, considering typical pedestrian scenarios based on LTE specifications. The numerical results show that the proposed suboptimal schemes achieve a performance very close to the optimal but with lower computational complexity. Moreover, the performance of the proposed per-BS precoding schemes is close to the one obtained considering TPC over a supercell.Portuguese CADWIN - PTDC/ EEA TEL/099241/200

Multi-cell cooperation for future wireless systems

Portuguese CADWIN - PTDC/EEA TEL/099241/2008Portuguese Foundation for Science and Technology (FCT

Minimum BER diagonal precoder for MIMO digital transmissions

International audienceWe propose a Minimum Bit Error Rate (MBER) diagonal Precoder for Multi-Input Multi-Output (MIMO)transmission systems. This work is based on previous results obtained by Sampath et al.[1] in which the global transmission system (precoder and equalizer) is optimized with the Minimum Mean Square Error (MMSE) criterion. This process leads to an interesting diagonality property which decouples the MIMO channel into parallel and independent data streams and allows to perform an easy ML detection. This system is then optimized using a new diagonal precoder that minimizes the BER. Our work is motivated by the fact that, from a practical point of view, people are likely to prefer a system that minimizes the BER rather than the Mean Square Error. The performance improvement is illustrated via Monte Carlo simulations using a Quadratic Amplitude Modulation (QAM)

Minimum BER Diagonal Precoder for MIMO Digital Transmissions

We propose a Minimum Bit Error Rate (MBER) diagonal Precoder for Multi-Input Multi-Output (MIMO) transmission systems. This work is based on previous results obtained by Sampath et al. [1] in which the global transmission system (precoder and equalizer) is optimized with the Minimum Mean Square Error (MMSE) criterion. This process leads to an interesting diagonality property which decouples the MIMO channel into parallel and independent data streams and allows to perform an easy ML detection. This system is then optimized using a newdiagonal precoder that minimizes the BER. Our work is motivated by the fact that, from a practical point of view, people are likely to prefer a system that minimizes the BER rather than the Mean Square Error. The performance improvement is illustrated via Monte Carlo simulations using a Quadratic Amplitude Modulation (QAM). 1

Recent Advances in Wireless Communications and Networks

This book focuses on the current hottest issues from the lowest layers to the upper layers of wireless communication networks and provides "real-time" research progress on these issues. The authors have made every effort to systematically organize the information on these topics to make it easily accessible to readers of any level. This book also maintains the balance between current research results and their theoretical support. In this book, a variety of novel techniques in wireless communications and networks are investigated. The authors attempt to present these topics in detail. Insightful and reader-friendly descriptions are presented to nourish readers of any level, from practicing and knowledgeable communication engineers to beginning or professional researchers. All interested readers can easily find noteworthy materials in much greater detail than in previous publications and in the references cited in these chapters