摘要：內置天線是現代手機普遍的選擇，能使手機的外形設計更加輕薄化，多樣化。也可以通過合理安排內置天線的位置，來抵消輻射對人體的影響。所以小型化、多頻段、智能化、多極化是移動通信未來發展的必然的趨勢。而微帶天線所特有的體積小、重量輕、低剖面、可共形的特點，使得它成為了手機內置天線最佳的選擇。因此，學習研究微帶天線的原理特性，對手機內置天線進行設計，對其性能進行仿真和分析的研究勢在必行。

　　　本文介紹了一種新型PIFA三頻手機天線，天線采取中心單饋點同軸饋電，在輻射片開兩個U型槽的方法，用軟件HFSS對天線進行設計和仿真，在GMS900MHz，DCS1800MHz和ISM2450MHz三個頻段的增益分別達到了0.32dBi,0.11dBi和0.613dBi，相對帶寬分別達到了7.8%，0.95%和3.9%。該天線可滿足多頻手機天線的要求，在三個頻段上都能夠正常工作，達到了新型無線通信天線系統對頻段、帶寬和增益的要求。

關鍵詞：平面倒F天線（PIFA）;三頻天線GSM900MHz/DCS1800MHz/ISM2450MHz; U型槽

Abstract：Internal antenna is a popular choice for modern handset. It can make The appearance of the handset  more  light and thin making and  more  diversity . Also It can make the reasonable arrangements for the location of internal antenna, to counteract the impact of radiation on the human body. Therefore, the miniaturization, multi-band, intelligentization, and multi-polarization are the inevitable trend of the future development of mobile communications. And the microstrip antenna with the unique characteristics such as small size, light weight, low profile, conformal deformation, has been the best choice of the internal antenna in handset. Therefore, the study of the principle characteristics of microstrip antenna, is imperative for the internal antenna design of phone, and the research of its performance simulation and analysis.

　　　This paper presents a new PIFA tri-band mobile phone antenna, the antenna takes the center single feed as coaxial feed, makes two U-shaped slots in the radiation-chip, and makes the antenna design and simulation by using HFSS software. three frequency band gain respectively reached 0.32 dBi, 0.11 and 0.613 dBi dBi, relative bandwidth achieved respectively 7.8%, 0.95% and 3.9% in GMS900MHz, DCS1800MHz and ISM2450MHz. It shows that the antenna can meet the antenna requirements of multi-band mobile phone, and can work normally in three bands, to reach the requirements of the new wireless communication antenna system for the band, bandwidth and gain.

Key words： PIFA; GSM900MHz/DCS1800MHz/ISM2450MHz;U-shaped slot