pifa天線(38)

1、以上天線都具有低剖面以上天線都具有低剖面(Low-Profile )特點(diǎn)特點(diǎn)現(xiàn)代通信面臨的挑戰(zhàn)現(xiàn)代通信面臨的挑戰(zhàn)# Signal Reliability# Minimize signal loss# Combat multipath fading effects# Power requirements# Miniaturization: Low Profile# Data rates# Frequency utilization1。The length of the patch (L) is typically about a third to a half of a free- space

2、wavelength (), .2。The dielectric thickness is in the range of 0.003 to 0.5. 3。A commonly used dielectric for such antennas is polytetrafluoral ethylene (PTFE), which has a relative dielectric constant of about 2.5.polytetrafluoral ethylene聚四氟乙烯聚四氟乙烯where f u and f l are upper and lower frequency of

3、bandwidth, f r is resonant frequency, Q is quality factor,R is loss component of antenna, L is inductive component of antenna, C is capacitive component of antenna,S is volume of antenna.工作頻率方向性相對帶寬當(dāng)接地板的尺寸為0.8時PIFA天線的相對工作帶寬為0.8%GSM:Global System for Mobile; DCS:Digital Cellular Sytem;PCS: Personal C

4、ommunication System; IMT: International Mobile Telecommunication ISM: Industrial , Scientifical, MedicalChromosome 染色體Mutate 變異計(jì)算結(jié)果2。1GHHz-2.56GHz電壓駐波比小于2的帶寬460MHz19.5%2.4GHz.110MHz 4.6%5.GHz 900MHz 18%inverted “F” antenna (IFA)Multiantenna development inone handset has become more and more common.開

5、縫可以使PIFA天線工作在多個頻率下。Integrated planar multi-band antennasUniversalMobile Telecommunication System (UMTS)(1920 2170 MHz）開縫雙頻天線Hilbert geometry 是一種分形幾何形狀是一種分形幾何形狀集總參數(shù)元件加載天線In most applications, the chip resistance is found to be in the range of3150 O, and reactance in the range of 20050 O (capacitive).IEEE，APS 2005, P.508Dual-Frequency Triangular Planar Inverted-F Antenn