Design of synchronisation sequences for mobile radio applications using genetic algorithms

This paper discusses the application of Genetic Algorithms (GAs) to the problem of searching for a set of synchronisation codes for TDMA based mobile radio systems. The problem may be formulated as a constrained optimisation problem and is transformed into an unconstrained one by including a penalty term within the fitness function. The quality of the sequences obtained, using the genetic algorithms, are compared with some previously published results. The paper discusses the sensitivity of the genetic algorithm's behaviour to the formulation of the fitness function and algorithm parameters. Using results from polyphase codes it is also shown how sets of sequences for different modulation formats can be obtained from either a BPSK or QPSK code.