The Research And Design Of Environmental Hybrid Energy Harvesting Rectenna

With the advent of the Internet of Things era,the application of low-energy electronic products has become more and more extensive,and the supply of energy for small electronic products has become a research hotspot in the industry.Using energy harvesting technology to obtain different energies in the natural environment and convert them into electrical energy for power supply for electronic products,it has a very promising development prospect.This dissertation studies the hybrid energy harvesting technology of light energy,radio frequency and vibration environment based on piezoelectric materials and solar thin films.By using piezoelectric materials and solar thin films as antenna dielectric layers,three types of integrated energy harvest antenna structures are formed,breaking the traditional single Limitations of energy harvesting.For the radio frequency and vibration energy harvesting modules,the corresponding rectifier circuit parts are designed to achieve the high efficiency design goal of the rectifier circuit.Finally,two environment hybrid energy harvesting rectifier antennas are designed and tested.The specific research content and design.The results are as follows:1.A sector-shaped environment hybrid energy harvesting antenna based on PVDF piezoelectric materials is designed.The antenna uses PVDF as the antenna medium and the surface is covered with sector-shaped copper stickers as the antenna radiating element,which realizes the miniaturized design of the antenna.The working bandwidth of the antenna is2.3GHz-2.7GHz and 3.9GHz-6GHz,the resonance points are 2.4GHz and 4.4GHz respectively,and the gains at the resonance point are 2.05d B and 2.7d B respectively;the first-order characteristic frequency of the PVDF material is 71Hz;2.Designed a hybrid energy harvesting antenna based on solar thin film and PVDF material in a stacked circular environment.The solar thin film is pasted on the lower surface of the PVDF material,and the two together form the antenna dielectric layer,and then the upper surface of the PVDF material is laminated the round copper sheet is the antenna radiating element.The working bandwidth of the antenna is 1.9GHz-2.8GHz,which can cover the 2.4GHz wireless Wi-Fi frequency band,the resonance point is 2.4GHz,and the gain at the resonance point is 3.4d B;the first-order characteristic frequency point of PVDF and solar film is 75Hz;3.For single-band and dual-band antennas,single-branch and dual-branch rectifier circuits are designed.The RF rectifier circuits are impedance matched through capacitors and inductors,and are made on the PCB board.The final measured efficiency of the single-band rectifier circuit at 2.4GHz is 58%;the measured efficiency of the dual-band rectifier circuit at 2.4GHz and4.4GHz 51%and 57%respectively;4.For the vibration energy harvesting part,a low-frequency rectifier circuit is designed.In order to improve the voltage value and stability of the output voltage,the optimization simulation of the low-frequency rectifier circuit is carried out in the simulation software Multisim.Finally,when the input voltage is 2V,the effective value of the voltage output and the conversion efficiency are 2.52V and 126.2%,respectively.Ripple voltage And its coefficients are 0.1V and 2.63%respectively,and the time for the output voltage to reach a steady state is0.29 seconds.5.Two environmental hybrid energy harvesting devices have been developed and tested in experiments.The environmental hybrid energy harvesting device based on piezoelectric materials at 2.4GHz,the output voltage of the RF part is 1.47V,and the output power is216.09?W;when the vibration frequency is 71Hz,the output voltage of the piezoelectric part is1.17V,output power is 684.45?W.The environmental hybrid energy harvesting device based on solar thin film and piezoelectric materials has a frequency of 2.4GHz,the output voltage of the radio frequency part is 1.77V,and the output power is 313.29?W;when the vibration frequency is 75Hz,the piezoelectric Part of the output voltage is 1.51V and the output power is 1.14m W.When the light intensity is 100m W/cm~2,the output voltage is 1.42V and the output power is2.0164m W,the output power value can meet the power supply requirements for low-energy electronic products.