Evolutionary Strategy-Based Approaches for Subcarrier, Bit, and Power Allocation for Multiuser OFDM Systems

Abstract

An evolutionary strategy (ES) scheme is proposed to solve the subcarrier, bit, and power allocation problem in this paper. By the property of the real-valued representation in the evolutionary strategy, the difficulties in coding with the geneticbased algorithms (GA) are conquered. This paper utilizes the method of the binary integer programming to perform the bit loading to overcome the limitation met in the water-filling algorithm. A fuzzy logic controller (FLC) is introduced to adjust the mutation probability in the iteration process. A simple subcarrier assignment modification step is also introduced to speed up the convergence rate and improve the performance. Simulation results are conducted to verify the features of better convergence rates with the proposed schemes, and the performance is improved.

Genetic Algorithm-Based Power Allocation for Multiuser MIMO-OFDM Femtocell Networks with ZF Beamforming

“…GA-based method has ever been applied in [30] for subcarrier allocation to minimize transmit power. In this paper, we utilize GA-based method for power allocation to maximize the SINR.…”

Hybrid Evolutionary Algorithm-based Schemes for Subcarrier, Bit, and Power Allocation in Multiuser OFDM Systems

“…1 illustrates the processing block diagram of the proposed HEA-based scheme in this paper. The scheme provided in Table 1 is one subcarrier for one gene to construct a chromosome and procedures are followed in all papers (Wang et al, 2005) (Reddy & Phora, 2007) (Pao & Chen, 2008). The encoding design can be integer, binary, or real-value.…”

“…In the methods (Wang et al, 2005) (Reddy & Phora, 2007), chromosomes with "good" genes are added in the initial population to improve the convergence rate. This concept is also adopted in the scheme (Pao & Chen, 2008) which generates a chromosome with good genes by employing the CIA method (Wong et al, 1999b) in the proposed ES-based schemes. It is believed that a better initial subcarrier assignment could achieve better performance (Wang et al, 2005) (Reddy & Phora, 2007) (Pao & Chen, 2008).…”

“…This concept is also adopted in the scheme (Pao & Chen, 2008) which generates a chromosome with good genes by employing the CIA method (Wong et al, 1999b) in the proposed ES-based schemes. It is believed that a better initial subcarrier assignment could achieve better performance (Wang et al, 2005) (Reddy & Phora, 2007) (Pao & Chen, 2008). The ES-based scheme (Pao & Chen, 2008) uses the integer representation for the solutions.…”

“…It is believed that a better initial subcarrier assignment could achieve better performance (Wang et al, 2005) (Reddy & Phora, 2007) (Pao & Chen, 2008). The ES-based scheme (Pao & Chen, 2008) uses the integer representation for the solutions. In this paper, an encoding scheme is discussed about the mapping between the binary-string representation and the integer representation in the solution.…”