Research On Electric Small Antennas Based On Composite Right/Left-Handed Transmission Line Theory

With the rapid development of modern wireless communication systems,people have paid great attention to the design of high performance,compact and low-cost antennas.Microstrip patch antennas are widely used because of their compactness,low profile,light weight and low cost.However,the size of the antenna still needs to be further reduced,because the communication terminal has less and less space left for the antenna.Based on the CRLH(Composite Right / Left-handed)linear theory,this thesis uses the linear theory of zero-order,negative-order and negative first-order resonances to be independent of the antenna's physical size to achieve the miniaturization of the antenna.Firstly,based on the SIW(Substrate Integrated Waveguide)resonator,an interdigitated groove is introduced.Based on the-1th order resonance,a composite left and right-hand antenna is designed.Since the antenna uses a triangular resonant cavity,the structure is more compact than a rectangular or circular SIW resonator slot antenna that operates in the same mode and has the same area.In addition,the interdigitated slot allows the antenna to have a lower operating frequency.Then,based on the SIW resonant cavity,a bow-tie shaped interdigitated groove is formed,which introduces a lower working frequency point than the bowtie groove alone,and thus not only achieves the antenna miniaturization,but also to achieve a dual-band work.