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Now showing items 21-30 of 30
Low Complexity Transmission Scheme with Full Diversity for Two-Path Relay Networks
(2014-01-06) [Poster]
In this work, we present a new low complexity scheme for two-path relay network to harvest maximum achievable diversity. We analyze the performance of the newly proposed two-path relay network by calculating the symbol error rate (SER) for arbitrary location of relays. It is shown that with this newly proposed scheme, two-path relay networks can mimic a 2x2 multiple-input mulitple-output (MIMO) system and achieve full diversity order of four. Simulations results are provided to verify and illustrate the analytical results.
Modeling of MAI in UWB System Using MGGD
(2014-01-06) [Poster]
Multivariate generalized Gaussian density (MGGD) is used to approximate the multiple access interference (MAI) and additive white Gaussian noise in pulse-based ultrawide bandwidth (UWB) system. The MGGD probability density function (pdf) is shown to be a better approximation of a UWB system as compared to Gaussian, Laplacian and Gaussian-Laplacian mixture (GLM). The similarity between the simulated and the approximated pdf is measured with the help of modified Kullback-Leibler distance (KLD). It is also shown that MGGD has the smallest KLD as compared to Gaussian, Laplacian and GLM densities. Finally, a receiver based on the principles of minimum bit error rate is designed for the MGGD pdf.
Threshold-based Adaptive Detection for WSN
(2014-01-06) [Poster]
Efficient receiver designs for wireless sensor networks (WSNs) are becoming increasingly important. Cooperative WSNs communicated with the use of L sensors. As the receiver is constrained, it can only process U out of L sensors. Channel shortening and reduced-rank techniques were employed to design the preprocessing matrix. In this work, a receiver structure is proposed which combines the joint iterative optimization (JIO) algorithm and our proposed threshold selection criteria. This receiver structure assists in determining the optimal Uopt. It also provides the freedom to choose U<Uopt for each frame depending upon the tolerable difference allowed for mean square error (MSE). It is possible to gain in terms of complexity savings without affecting the BER performance of the system.
A Coalition Formation Game for Transmitter Cooperation in Uplink Communications
(2014-01-06) [Poster]
On Achievable Rates of Cognitive Radio Networks using Multi-layer Coding
(2014-01-06) [Poster]
On the Symbol Error Rate of M-ary MPSK over Generalized Fading Channels with Additive Laplacian Noise
(2015-01-07) [Poster]
This work considers the symbol error rate of M-ary phase shift keying (MPSK) constellations over extended Generalized-K fading with Laplacian noise and using a minimum distance detector. A generic closed form expression of the conditional and the average probability of error is obtained and simplified in terms of the Fox’s H function. More simplifications to well known functions for some special cases of fading are also presented. Finally, the mathematical formalism is validated with some numerical results examples done by computer based simulations [1].
Energy-Efficient Power Allocation of Cognitive Radio Systems without CSI at the Transmitter
(2015-01-07) [Poster]
Two major issues are facing today’s wireless communications evolution: -Spectrum scarcity: Need for more bandwidth. As a solution, the Cognitive Radio (CR) paradigm, where secondary users (unlicensed) share the spectrum with licensed users, was introduced. -Energy consumption and CO2 emission: The ICT produce 2% of global CO2 emission (equivalent to the aviation industry emission). The cellular networks produces 0.2%. As solution energy efficient systems should be designed rather than traditional spectral efficient systems. In this work, we aim to determine the optimal energy efficient power allocation of CR when the channel state information at the transmitter CSI-T is not available.