Optimization of wirless optical communication system with placement of relay using shuffled frog leaping algorithm
01 Jan 2013-
TL;DR: This paper addresses the major limiting factor for links measuring more than a kilometer; the error rate performances is dismal and therefore relay assisted transmission is employed to combat this shortcoming.
Abstract: Wireless Optical communication (WOC) is improved using relay assisted transmission which exploits multiple shorter hops that gives a better performance gain. Relay assisted transmission is utilized as a mitigation tool in combating atmospheric turbulence occurring in the communication channels. The main aim is to minimize the outage probability and optimize relay locations for parallel and serial FSO relaying. In this paper we address the major limiting factor for links measuring more than a kilometer; the error rate performances is dismal and therefore relay assisted transmission is employed to combat this shortcoming. The focus of this study is on considering the channel model, which takes into account both path-loss and turbulence-induced fading. The locations of the relay are found out using different algorithms and then compared to find out the best optimized result.
References
More filters
Book•
05 Jan 1998
TL;DR: Introduction to Optimization The Binary genetic Algorithm The Continuous Parameter Genetic Algorithm Applications An Added Level of Sophistication Advanced Applications Evolutionary Trends Appendix Glossary Index.
Abstract: Introduction to Optimization The Binary Genetic Algorithm The Continuous Parameter Genetic Algorithm Applications An Added Level of Sophistication Advanced Applications Evolutionary Trends Appendix Glossary Index.
4,006 citations
01 Jan 2001
TL;DR: The genetic algorithm using a oat representation is found to be superior to both a binary genetic algorithm and simulated annealing in terms of e ciency and quality of solution.
Abstract: A genetic algorithm implemented in Matlab is presented. Matlab is used for the following reasons: it provides many built in auxiliary functions useful for function optimization; it is completely portable; and it is e cient for numerical computations. The genetic algorithm toolbox developed is tested on a series of non-linear, multi-modal, non-convex test problems and compared with results using simulated annealing. The genetic algorithm using a oat representation is found to be superior to both a binary genetic algorithm and simulated annealing in terms of e ciency and quality of solution. The use of genetic algorithm toolbox as well as the code is introduced in the paper.
1,318 citations
01 Nov 2007
TL;DR: This paper considers an aggregated channel model which takes into account both path-loss and turbulence-induced log-normal fading in free-space optical systems operating in atmospheric turbulence channels and derived closed form expressions for outage probability of the relaying schemes under consideration.
Abstract: In this paper, we present relay-assisted transmission as a powerful fading mitigation tool for free-space optical systems operating in atmospheric turbulence channels. We study both serial (i.e., multi-hop transmission) and parallel (i.e., cooperative diversity) relaying encoupled with amplify-and-forward and decode-and-forward modes. We consider an aggregated channel model which takes into account both path-loss and turbulence-induced log-normal fading. Since fading variance is distance-dependent in free-space optical systems, relay-assisted transmission takes advantage of the resulting shorter hops and yields significant performance improvements. We derive outage probability of the relaying schemes under consideration which are further confirmed through Monte-Carlo simulations. Our outage probability analysis demonstrates that an impressive performance improvement of 18.5 dB is possible with the use of a single relay at a target outage probability of 10-6.
549 citations
"Optimization of wirless optical com..." refers background in this paper
...This threshold is essential for avoiding any propagation error [2]....
[...]
...It is possible only when the received SNR is greater than the outage-threshold [2]....
[...]
...where k is the wave number and C(2)n denotes the constant refractive index structure [1-3]....
[...]
TL;DR: In this paper, a shuffled frog leaping algorithm (SFLA) is proposed for optimal placement and sizing of distributed generation in radial distribution system to minimize the total real power loss and to improve the voltage profile.
Abstract: Optimal placement and sizing of DG in distribution network is an optimization problem with continuous and discrete variables. Many researchers have used evolutionary methods for finding the optimal DG placement. This paper proposes a shuffled frog leaping algorithm (SFLA) for optimal placement and sizing of distributed generation (DG) in radial distribution system to minimize the total real power loss and to improve the voltage profile. The SFLA is a meta-heuristic search method inspired from the memetic evolution of a group of frogs when seeking for food. It consists of a frog leaping rule for local search and a memetic shuffling rule for global information exchange. The proposed SFL algorithm is used to determine optimal sizes and locations of multi-DGs. Test results indicate that SFLA method can obtain better results than the simple heuristic search method on the 33-bus radial distribution systems. Moreover, voltage profile improvement and branch current reduction are obtained.
52 citations
"Optimization of wirless optical com..." refers background or methods in this paper
...Thus, the main SFL parameters are: P, number of frogs, memeplexes, generations for every such memeplex right before shuffling, shuffling iterations, and the maximum step size [4-5]....
[...]
...As the number of relays increases the outage probability decreases, and therefore it is recommended to use more number of relays in parallel technique [4-6]....
[...]
08 Dec 2011
TL;DR: The analytical and simulation results show that the closed-form expression can provide sufficient precision for evaluating outage performance of parallel relay-assisted FSO communications.
Abstract: This paper investigates the performance of parallel relay-assisted transmission for free-space optical (FSO) communication systems over strong turbulence channel. The analysis is carried out for systems employing decode-and-forward (DF) relays and for strong turbulence channel which can be modeled by the Gamma-Gamma distribution. Take atmospheric attenuation, atmospheric turbulence and pointing errors into account, a statistical model for the optical intensity fluctuation at the receiver is presented. For given weather and misalignment conditions, an exact analytical expression for the end-to-end outage probability of DF systems is obtained. The analytical and simulation results show that the closed-form expression can provide sufficient precision for evaluating outage performance of parallel relay-assisted FSO communications.
45 citations