An Improved PSO for Design Optimizations of a Multiband Rectenna for Miniature Energy Harvester

The environmental electromagnetic field consists of different frequency components with very low energy densities. In this regard, an ideal miniature energy harvester should be a multi-resonance frequency, wide-frequency band, generally called multiband, high- gain one in order to collect enough electromagnetic energy from environmental electromagnetic fields. In this point of view, a microstrip multiband rectenna is proposed for miniature energy harvesters. Since the tuning of the physical parameters of the proposed rectenna is not an easy task considering the requirements on a multiband and a high gain, an improved particle swarm optimization (PSO) method is proposed. The numerical results have demonstrated that the optimized rectenna obtains high gains in multi-resonance frequency band.