Miniaturized Antennas for Platform-level Integration Scenarios.

Miniaturized;Integrated Antennas;Electrical Engineering;Engineering;Electrical Engineering

Hong, WonbinShtein, Max ;

University of Michigan

关键词: Miniaturized;    Integrated Antennas;    Electrical Engineering;    Engineering;    Electrical Engineering;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/63710/wonbin_1.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

Efforts to reduce the physical dimension of an antenna have been vigorously studied for many decades. Through the collection of such efforts, the effects of sizereduction on the performance of an antenna are fairly well understood matters inpresent day. The fundamental limitations established by Wheeler and Chu havebeen referenced as theoretical guidelines for acquiring smaller antenna size at theexpense of radiation resistance, antenna Q (bandwidth) and polarization. Whileperformance degradation is inevitable using contemporary materials as a resonantantenna volume decreases, it is still possible to overcome this restriction by taking adifferent route. Techniques such as facilitation of mutual coupling effects of parasiticelements, utilization of transistors, capacitive and inductive loading methods andartificial materials are now employed to mitigate and curb the inverse relationshipbetween antenna volume and performance.This dissertation continues the path of designing fully integrated, electrically smallantennas in a controlled manner. The contributions of this dissertation include:A method to reduce the dimension of a cavity-backed slot antenna is synthesized.For a simple straight slot antenna, this technique can reduce the overall occupiedvolume of the modified cavity backing the slot antenna by more than 65%without effecting the high radiation effciency of the antenna. This facilitatesproper fabrication and integration of miniaturized slot antennas on multi-layersubstrates.A platform-integrated low-profile antenna with high isolation levels to its environment is reported. Through this approach, complex package-level designs andsimulations can be greatly simplified as the antenna exhibits similar behaviorwhen integrated as it does in open-space. The method enables the realizationof unidirectional cavity-backed slot antennas with heights less than lambda/100, minimizing surface intrusion or protrusion for platform antenna implementations.An infinitesimal electric dipole radiating vertical polarization with less thanlambda/100 height is realized. The theoretical equivalence relation between a shortelectric dipole and a magnetic loop at resonance is valid under the following preconditions: 1) The existence of uniform in-phase magnetic current, 2) Impedance matching to the low radiation resistance of the magnetic loop. Thisdissertation is the first to satisfy both requirements to the best of my knowledge.