Research On Low Profile Miniaturized Antenna Based On Artificial Magnetic Conductor

With the development of Mobile Communication,Internet of things and various electronic industries,antenna as one of the most important receiving and transmitting devices,has higher requirements for the design of antenna with low profile and miniaturization with the development of electronic equipment.With the rapid development of metamaterials,the research of artificial magnetic conductor(AMC)with high impedance and in-phase reflection has a rapid development.The artificial magnetic conductor can replace the traditional metal plate as the reflector of the antenna to reduce the height of the antenna section.In this paper,the low profile antenna based on the artificial magnetic conductor is taken as the research object.How the AMC structure can reduce the height of the antenna profile is studied deeply.Two kinds of new AMC structures with different working frequencies are proposed.The main contents research resultsof this paper as follows:(1)A square ring center connected AMC structure and a double circular ring structure are designed.Based on the traditional square ring AMC structure.the square ring AMC structure is connected with the central ring structure by loading four rectangular patches.thus fomming an equivalent LC circuit on the surface of the structure to obtain the coupling characteristics.The simulation results show that the in-phase reflection bandwidth of AMC is 4.5ghz-5.4ghz(20%).The designed double circular ring structure consists of an external ring and a central circular patch.The parameters of the structure are also simulated and analyzed to obtain the characteristics of in-phase reflection and high impedance.The measured and simulation results show that the[-90°,+90°]of the structure is 2.4GHz-2.60GHz(8%).(2)Alow profile antenna based on double-circular AMC structure is designed.The antenna consists of a half wave dipole structure and a double circular AMC structure.The role of AMC structure is verified by the half wave dipole antenna,and the antenna loaded with AMC structure is compared with the antenna loaded with PEC structure.The simulation results show that the impedance bandwidth of the antenna is 2.35GHz-2.6GHz(13.4%).the gain in the maximum direction is 7.6db,and the profile height of the antenna is 0.05),about 7.6mm.(3)A low profile polarization slot antenna based on AMC structure with square ring central connection is designed.The antenna is composed of horn type slot antenna and AMC reflector,which is fed by CPW.The upper horn type slot antenna generates bidirectional radiation wave.The AMC structure loaded on the lower layer makes the reflection wave and forward wave superposed to obtain unidirectional radiation.The square ring center connected AMC structure with the same working frequency band is loaded.Through its in-phase reflection characteristics,the antenna performance is not affected at the same time.The measured and simulation results show that the impedance bandwidth of the antenna is 4.75ghz-5.25ghz(10%),the maximum gain is 7.6 dB,and the profile height is 0.05?,about 5mm.