一种加载磁电超表面的宽带多频贴片天线

A Wideband Multi-frequency Antenna by Loading MED-WG-MTM

利用磁电超表面概念通过在等腰直角三角形天线贴片和接地面上分别蚀刻周期互补开口谐振环和十字缝隙图案并将天线对应的地板位置截取掉一部分分别构建了单元1和单元2,分析了其左手特性和提高高频端增益的工作机理,最终加载单元2制作了一款宽带多频贴片天线。仿真结果表明,所提出的天线具有4个带宽并且能够覆盖2.4/5.2/5.8 GHz的蓝牙/RFID/WLAN和2.5/3.5 GHz的Wi MAX频带,这4个频带的带宽分别是0.29GHz(2.33~2.62 GHz),1.01 GHz(3.11~4.12 GHz),0.39 GHz(4.97~5.36 GHz),0.41 GHz(5.74~6.15 GHz)。由于接地板上蚀刻的超材料结构的左手特性影响了天线介质基底的等效媒质参数,天线电磁场的传播方向被改变,在高频端,天线辐射场主要集中在水平方向而不是传统贴片天线的垂直方向。

Cell one is fabricated using the magneto-electro-dielectric waveguided metamaterials, MED-WG-MTM via the periodically loaded complementary split-ring resonators（CSRRs） on the upper isosceles right triangle patch and cross-slot on the bottom ground plane, respectively, on the basis of cell one, intercepting a part of bottom ground plane below the patch to fabricate cell two. Analyze the left-handed characteristic and the mechanism of enhancing the gain at higher frequency part. A wideband multi-frequency patch antenna is fabricated by loading cell two, finally. The simulation results show that the patch antenna presents the desired four bandwidths which cover all the 2.4/5.2/5.8 GHz Bluetooth/RFID/WLAN bands and the 2.5/3.5 GHz WiMAX band, including 0.29 GHz（2.33 -2.62 GHz）, 1.01 GHz（3.11 -4.12 GHz）, 0.39 GHz （4.97 - 5.36 GHz）, 0.41 GHz （5.74 - 6.15 GHz）. Due to the fact that the effective medium parameters of substrate of an- tenna are affected by the left-hand characteristic, the wave propagation direction of antenna is changed, which induces the strongest radiation been in horizontal direction rather than the vertical direction of the conventional patch antenna at higher frequency part.