基于左手介质后向波特性的微带天线小型化研究

Investigation on the miniaturization of the microstrip antenna based on the backward wave property of left-handed medium

基于色散性稳定、频带宽、电尺寸小的左手介质结构单元,设计了一种左手介质和传统介质相结合的微带天线基板结构,利用左手介质的后向波效应对传统介质中传播后的电磁波进行相位补偿,从而实现微带天线小型化设计.理论计算和数值仿真结果表明,工作于4·7GHz的微带天线的物理尺寸被减小了37·92%,突破了传统微带天线的半波长要求的限制,而小型化的微带天线的增益、带宽等性能方面与传统天线相当,证明了用左手介质小型化微带天线的可行性和实用性.

Based on a left-handed medium （LHM） structure unit with smooth dispersion, broadband property and of electrical small dimensions, a microstfip antenna （MSA） substrate is designed partially loaded by both the LHM and the conventional dielectric medium for the miniaturization of MSAs, in which the backward wave property of LHM is employed to compensate for the phase shift resulting from waves propagating in the conventional dielectric medium. Both the analytical and numerical results demonstrate that the physical dimensions of a 4.70 GHz MSA have been significantly reduced by 37.92 %, and can be no longer proportional to the working wavelength, while its bandwidth and gain can be equivalent to that of a conventional MSA. All above results indicate the practical capability of LHM in the miniaturization of MSAs.