基于结构合成法的微型化双频WLAN印刷天线设计

Design of miniaturized dual-band WLAN printed antenna based on structural synthesis

针对当前WLAN技术的快速发展和已有的双频WLAN印刷天线存在增益不足、带宽较窄、尺寸偏大、制作成本高等缺陷的现状,本文借鉴了传统倒F印刷天线和蛇形单极子印刷天线的设计经验,提出了一种新的双频印刷天线设计方法,即结构合成法,并采用该方法设计了一种应用于IEEE 802.11a标准和IEEE 802.11b标准、占用面积仅13.6 mm×9.3 mm的新型微型化双频WLAN印刷天线。采用Ansoft HFSS对比研究了合成前后单频天线和双频天线的性能变化情况,并对双频天线的主要结构进行了分析和优化。仿真结果表明,天线在2.45 GHz和5.45 GHz两个谐振频点上的最高增益分别达2.74 d Bi和2.44 d Bi,相对带宽分别为15.5%和10.6%。此外,文中采用矢量网络分析仪对天线实物进行了测试,实测结果与仿真结果吻合,天线在低频和高频的谐振频点分别为2.53 GHz和5.71 GHz,S11<-10 d B的有效带宽分别超过了400 MHz和500 MHz,展现出了良好的带宽特性。

Under the currently rapid development of WLAN, the main drawbacks of exiting Dual-Band WLAN printed antenna include gain deficiencies, narrow effective bandwidth , too large size and high production cost. To solve these problems, this paper proposes a new structural synthesis design for Dual-Band printed antenna based on the traditional design experience of inverted-F printed antenna and the snake monopole printed antenna. The approach adopts the design of a new miniaturized Dual-Band WLAN printed antenna, which can comply with the standards of IEEE 802. lla and IEEE 802. lib. The occupied area of the antenna only 13.6 mm x9.3 mm. The paper adopts Ansoft HFSS to compare the performance of single-frequency and dual-band antenna before and after synthesis, and carries out analysis and optimization of the main structure for the latter. The results of validation simulations reveal that the maximum gain of 2.45 GHz frequency and 5.45 GHz frequency are 2.74 dBi and 2.44 dBi respectively. The relative bandwidths are 15.5% and 10.6% respectively on the two resonant frequencies. Besides, this study also adopts the vector network analyzer to test the return loss of the fabricated antenna. The testing results are consistent with the simulated results. The resonant frequencies of high and low bound are 2.53 GHz and 5.71 GHz respectively. The available bandwidths of Sll 〈 -10 dB are more than 400 MHz and 500 MHz respectively, which shows good bandwidth.