OUTAGE PERFORMANCE OF COGNITIVE RF/FSO SYSTEM WITH MRC SCHEME AT THE RECEIVER

The aim of this paper is performance analysis of the hybrid radio frequency (RF)/free-space optical (FSO) system, where the transmission is performed simultaneously over FSO link and spectrum sharing cognitive RF sub-system. The FSO link is affected by Gamma-Gamma atmospheric turbulence, while in spectrum sharing cognitive RF sub-system the peak interference power constraint at the primary user's receiver is considered in Nakagami-m fading environment. Outage probability expressions are provided in the integral form for the case when the maximal ratio combining (MRC) is applied at the destination. The effects of the atmospheric turbulence strength, the number of RF antennas, allowable power and fading severity on the outage performance are observed. Numerical results are presented and verified by Monte Carlo simulations

Information theory and coding: solved problems

This book is offers a comprehensive overview of information theory and error control coding, using a different approach then in existed literature. The chapters are organized according to the Shannon system model, where one block affects the others. A relatively brief theoretical introduction is provided at the beginning of every chapter, including a few additional examples and explanations, but without any proofs. And a short overview of some aspects of abstract algebra is given at the end of the corresponding chapters. The characteristic complex examples with a lot of illustrations and tables are chosen to provide detailed insights into the nature of the problem. Some limiting cases are presented to illustrate the connections with the theoretical bounds. The numerical values are carefully selected to provide in-depth explanations of the described algorithms. Although the examples in the different chapters can be considered separately, they are mutually connected and the conclusions for one considered problem relate to the others in the book

Adaptive vector quantization in SVD MIMO system backward link with limited number of active sub channels

This paper presents combination of Channel Optimized Vector Quantization based on LBG algorithm and sub channel power allocation for MIMO systems with Singular Value Decomposition and limited number of active sub channels. Proposed algorithm is designed to enable maximal throughput with bit error rate bellow some tar- get level in case of backward channel capacity limitation. Presence of errors effect in backward channel is also considered

Performance Analysis of Nonlinear Energy‐Harvesting DF Relay System in Interference‐Limited Nakagami‐

A decode‐and‐forward system with an energy‐harvesting relay is analyzed for the case when an arbitrary number of independent interference signals affect the communication at both the relay and the destination nodes. The scenario in which the relay harvests energy from both the source and interference signals using a time switching scheme is analyzed. The analysis is performed for the interference‐limited Nakagami‐m fading environment, assuming a realistic nonlinearity for the electronic devices. The closed‐form outage probability expression for the system with a nonlinear energy harvester is derived. An asymptotic expression valid for the case of a simpler linear harvesting model is also provided. The derived analytical results are corroborated by an independent simulation model. The impacts of the saturation threshold power, the energy‐harvesting ratio, and the number and power of the interference signals on the system performance are analyzed

Energy detector performance in Rician fading channel

In this paper we analyzed the problem of detection of unknown signals in the Rician fading channel. A closed-form expression for the probability of detection is derived, followed by the numerical results. The analysis was extended to the case of cooperative sensor network in which the environment can be modelled by independent Rician fading channels

Learning to Decode Linear Block Codes using Adaptive Gradient-Descent Bit-Flipping

In this paper we propose a generalization of the recently published adaptive diversity gradient-descent bit flipping (AD-GDBF) decoder, named generalized AD-GDBF (gAD-GDBF) decoder. While the original AD-GDBF decoder was designed for the binary symmetric channel and used mostly to decode regular low-density parity-check codes, the gAD-GDBF algorithm incorporates several improvements which makes it eligible for the additive white Gaussian channel and decoding of arbitrary linear block code. The gAD-GDBF decoder uses the genetic algorithm to optimize a set of learnable parameters, for a targeted linear block code. The effectiveness of the proposed method is verified on short Bose-Chaudhuri-Hocquenghem (BCH) codes, where it was shown that for the same number of decoding iterations the gAD-GDBF decoder outperforms the belief-propagation decoder in terms of bit error rate and at the same time reduces the decoding complexity significantly.Science Fund of the Republic of SerbiaImmediate accessThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Performance Analysis of Wirelessly Powered Cognitive Radio Network with Statistical CSI and Random Mobility

The relentless expansion of communications services and applications in 5G networks and their further projected growth bring the challenge of necessary spectrum scarcity, a challenge which might be overcome using the concept of cognitive radio. Furthermore, an extremely high number of low-power devices are introduced by the concept of the Internet of Things (IoT), which also requires efficient energy usage and practically applicable device powering. Motivated by these facts, in this paper, we analyze a wirelessly powered underlay cognitive system based on a realistic case in which statistical channel state information (CSI) is available. In the system considered, the primary and the cognitive networks share the same spectrum band under the constraint of an interference threshold and a maximal tolerable outage permitted by the primary user. To adopt the system model in realistic IoT application scenarios in which network nodes are mobile, we consider the randomly moving cognitive user receiver. For the analyzed system, we derive the closed-form expressions for the outage probability, the outage capacity, and the ergodic capacity. The obtained analytical results are corroborated by an independent simulation method