A Research Of Intelligent Decision Engine Of OFDM System Based On Genetic Algorithm

Cognitive radio become to the focus of the next generation of communication inrecent years, many of the key ideas can also be applied to the related fields, intelligentdecision-making as one of the core of cognitive radio plays an important role in thefuture development of communication. this paper works on anti-jamming intelligentdecision engine of OFDM system based on genetic algorithm, main work is divided intothree parts, described as follows:The first part states the concept, classification, and structure of the anti-jammingintelligent decision engine, introduce the corresponding concept, Classification andstructure of anti-jamming intelligent decision engine, the main work is focus on theperformance of the engine based on different algorithms such as genetic algorithm,quantum genetic algorithm, simulated genetic algorithm and particle swarm algorithm,the simulation shows that the genetic algorithm has a better performance in globaloptimization, It’s fast convergence and accurate search results make it a perfectalgorithm in decision-making unit; two algorithms including case based reasoning andrule based reasoning for learning unit is introduced too.The second part of this article will be based on the application of thedecision-making unit of the genetic algorithm to the OFDM systems, first design aframework of intelligent decision engine, then go for Subcarrier-Bit power allocationof OFDM system: to begin with a decision unit based on genetic algorithm, thenanalysis genetic algorithm and traditional bit power allocation algorithm, the simulationresults states: when the objective function is minimize transmit power, the decision unitwill have less transmit power than traditional bit power allocation algorithm; this partalso make an improvement of genetic algorithm including add an good gene and avariation mutate possibility, which shows a enhance performance; meanwhile, thispart also study in Modulation mode selection of OFDM system, and make a comparisonbetween genetic algorithm and fixed threshold algorithm, the result shows that thegenetic algorithm has a less BER but a less BPS.The third part of this article will be based on the decision-making unit of the genetic algorithm under the jamming circumstance of OFDM system. First give aframework of anti-jamming decision engine, when the jamming is relative small, thedecision unit will reserve all the sub-band to retain a higher transmission rate, when thejamming is relative high, decision unit will transmit data on the cleaning sub-band, inorder to reach an anticipate BER, then this part analysis the performance of theintelligent decision engine under partial band jamming, the result shows: decision unitwill adjust the transmit parameter based on the different channel quality, so that make awell tradeoff between BER and BPS.This work has a certain meaning for intelligent anti-jamming communicationssystems and provides research ideas for future follow-up work.