Development Of Dual-frequency Microstrip Receiving Antenna Based On Zero-refractive Index Metamaterial

Simultaneous Wireless information and Power Transfer(SWIPT)is a new type of wireless communication that can simultaneously transmit signals and energy,that is,to provide energy for wireless devices while interacting with the wireless devices.The antenna is a key component of the SWIPT energy harvesting system,and its miniaturization and high gain are the main technical goals.The traditional dual-band microstrip antenna has the advantages of easy processing,small size,low price,etc.,but the bandwidth is narrow and the gain is low.In response to these shortcomings,this article uses the method of adding notches and zero refractive index metamaterials(ZIM)to improve it.The main work is as follows:1.The research background of SWIPT is introduced in detail;the research overview of ZIM is explained,including the basic concepts and classifications,and the application in antennas;and the basis and research significance of the subject are explained.2.The theoretical explanation and basic properties of artificial electromagnetic metamaterials are introduced;the realization principle of zero-refractive index metamaterials and its electromagnetic characteristics are analyzed;the near-field and far-field parameters of the antenna are introduced.3.The transmission line model of the microstrip antenna is analyzed,and the general size calculation formula is written into the Matlab program;the inversion parameter method of metamaterials is introduced,and a ZIM with a near-zero dielectric constant is verified;a matching coaxial microstrip antenna is designed,which is combined with a zero-refractive metamaterial(ENZ)with a near-zero dielectric constant.The simulation results show that the gain is improved,which verifies that ZIM is helpful for the improvement of microstrip antenna gain.4.A dual-band microstrip antenna with a "tu" notch is designed.The traditional dual-band microstrip antenna has resonance frequencies at 2.45 GHz and 5GHz,dimensions of25.6mm×59.2mm,and bandwidths of 80 MHz and 290 MHz,respectively;after a lot of simulation,the microstrip antenna with a “tu” notch shows the size Reduced to 20 mm ×52mm,the bandwidth increased by 20 MHz and 210 MHz at low and high frequencies.5.Designed a "hui" font ZIM.There are two zero-refractive-index frequency bands,which are 2.26 ~ 2.64 GHz and 4.71 GHz ~ 5.11 GHz respectively,covering the resonant frequency point of a dual-band antenna with a "tu" notch.The ZIM structure is loaded on the antenna in the form of an array.The simulation results show that the gain has increased.The gains at 2.45 GHz and 5GHz are 4.96 dBi and 5.83 dBi,respectively.6.Draw a CAD model of the microstrip antenna with a "tu" notch and the "hui" zigzag array and make it into a physical object.The near-field and far-field parameters of the antenna were tested using a network vector analyzer and a microwave anechoic chamber respectively,mainly including the S11 before and after loading the ZIM array,the two-dimensional pattern and gain of the loaded metamaterial antenna.The test results show that the resonance frequency of the S11 curve is slightly shifted,the gain is not much different,and the overall effect meets the design requirements.