Design And Research Of Multiband Antenna Based On Miniaturization

As the important part of the signal transceiver system in portable devices,the size of antenna should meet the demand of miniaturization.In addition,the realization of multiband characteristic based on miniaturization is not only conducive to intersystem integration,but also makes better use of spectrum resources and improves the work efficiency of antenna.This paper focuses on the research hotspot of multiband antenna design based on miniaturization.Through the analysis and summary of the antenna's multi-frequency technology and miniaturization technology and the practice of engineering,four kinds of multiband antennas for different uses are designed.Among the four types,metamaterial technology is used flexibly in the design of three of them,which optimizes the performance of the antenna and provides a new idea for the antenna design.The overview and innovation of four antennas are described below:The first type of antenna is a kind of dual-band antenna for GSM/DCS with simple structure and good performance.The innovation of this antenna is the introduction of the rectangular ring structure based on the left-handed material,which makes it possible that the gain in the two bands is increased and the bandwidth of the high-frequency section is also increased.The second type of antenna is a dual-band antenna which can be applied to RFID tag antenna.The size of the antenna is small,which is only 30mm*19.1mm*0.7mm,and the structure is simple and easy to adjust.The innovation of this antenna is the introduction of the bending line structure which is inspired by ENG material.Because of this structure,the problem of large capacitance over electrically small antenna is overcame and good conjugation matching with the tag chip in the dual-band resonance frequency is achieved.This matching method solves the problem of external structure,oversized antenna and complex industrial integration in the traditional one.The third type of antenna is a kind of triple-band antenna which can be applied to a RFID reader.This kind of antenna has good characteristics of wideband and circular polarization.The innovation is that it can cover three different frequency bands on the basis of miniaturization at the same time.And by introducing the defected ground structure,the gain of the antenna is increased in the three frequency bands.In addition,this design increases the bandwidth of low-frequency and middle-frequency bands by introducing square slot electromagnetic band gap structure floor.The fourth type of antenna is a triple-band printed slot antenna,which can be applied to WLAN/WiMAX.The innovation of this antenna is that its size is small,which is only 38mm*34mm*1.6mm.And the structure is simple and easy to adjust.It can cover three frequency bands of WLAN/WiMAX.The gain curve is stable and the gain is high near the resonant frequency,the antenna has good directivity at the same time.