Improving Performance of Fuzzy-Based Handoff for Spectrum Utilization in Cognitive Radio Network Using Particle Swarm Optimization

Cognitive Radio Network (CRN) has received attention as it is considered a potential method to solve the issue of limited and rare spectrum resources for improving the capacity of wireless communication. One of the fundamental requirements of dynamic spectrum access in CRN is the handoff decision made by the Secondary User (SU) when the Primary User (PU) uses his channel. Previously, fuzzy algorithm was proposed to solve the handoff problem in CRN by several researchers. In this study together, we propose to use Particle Swarm Optimization (PSO) in optimizing the Membership Function (MF) to improve the performance of fuzzy-based handoffs to reduce the occurrence of incorrect handoffs. The proposed scheme consists of two parts that are Fuzzy Logic Controllers-1 (FLC-1) and Fuzzy Logic Controllers-2 (FLC-2). The first part (FLC-1) is used to control SU power and to avoid interference with PU, while part 2 (FLC-2) is used to support accurate spectrum handoff decisions. Based on the simulation results, it shows that the number of handoff spectra has decreased by 30% for all MF optimization on FLC-2 (MFFLC-2), then 50% for MF optimization on Psu only (MFPsu), and 70% for MF on fuzzy, which does not optimize using PSO. Thus, the optimization of MF on the fuzzy system can improve the performance of the fuzzy-based handoff scheme at CRN by precisely reducing the number of handoffs.