摘要：随着世界范围内移动通信系统的发展，在人们剩余劳动价值的大量储备的时代，手机也逐渐成为人们日常生活不可或缺的必须工具。在手机功能不断增加和完善的同时，也对手机提出了小型化、多频化和宽频带等要求，这就对手机天线的设计带来了更大的挑战。手机天线小型化是一个趋势。手机内置天线具有不易损坏、不易受屏蔽、对人体辐射伤害小等优点成为当今手机天线设计的首选。平面倒F天线(PIFA)满足尺寸小，重量轻并且信号不易被屏蔽，对人体辐射伤害小等优点而成为目前广泛受到应用的内置天线的主要形式。本次通过研究，设计了一个适用于WCDMA频段的小型宽频带PIFA手机天线，天线工作频率频段1900～2100 MHz。基于矩形贴片结构的基础，对手机天线加载一定缝隙来增加频带宽度，通过优化短路点和馈点之间的距离降低手机天线的回波损耗，通过优化贴片的形状、大小稳定中心工作频率提高手机天线的工作性能。利用HFSS（Ansoft公司的基于矩量法计算的三维仿真软件）进行三维仿真，然后进一步对天线的整体尺寸、缝隙的长和宽、贴片到接地面的距离进行优化和设计，得出最终理想结果。

关键词:  平面倒F天线； 带宽 ；宽带码分多址

Abstract：with the worldwide development of the mobile communications system．In the era of large reserves of the people's surplus labor value ，Mobile phone has became essential to daily life．With the mobile phone function increases ceaselessly and perfectly ，also a miniaturized multi-frequency and large bandwidth had been required．this brings more challenges to the mobile phone antenna design．

Mobilephone antenna miniaturization isa trend．Mobile phone antenna is the first choice of mobile phone antenna design because for uneasily damaged, difficult to shield and the less human radiation damage． Planar inverted F antenna ( PIFA ) meets the small size，light weight , the signals which uneasy to be shielded and has the allvantage of small radiation injury to human body , so it becomes the widespread application of the built-in antenna．An PIFA mobilephone antenna which is appied in WCDMA(1900～2100 MHz) frequency bandisdesigned．Based on the rectangular patch structure loading one crevice on mobile phone antenna，a certain gap to increase bandwidth， through the shorting wall and the feed point with the optimization to decrease the mobile phone antenna echo loss．Through the optimization of patch shape and size，stabled the center working of frequency to improve the performance of mobile phone antenna．Using HFSS ( From the Ansoft company which based on the moment method of calculating the three-dimensional simulation of 3D simulation software )， and then to optimizate and design with the total size of the antenna， slot length and width, patch to ground distance，achieved the final ideal result．

Keywords :  PIFA  Broad-Band  WCDMA