Click here to load reader

Antennas for Cell-Phones

  • View
    2.845

  • Download
    2

Embed Size (px)

DESCRIPTION

An antenna is the most important device in a cell-phone in terms of wireless communication. If the antenna doesn't work very well, the signal strength drops drastically. For the design of cell-phone antennas, we can adopt a dipole, helical, PIFA (Planar Inverted F Antenna), or intennas.

Text of Antennas for Cell-Phones

2. First Cell-Phone Dr. Martin Cooper in MotorolaMotorola RAZR Thin phone: 7.1 [mm]2 3. Trend in Cell-Phone Development Volume and weight Weight [g]Volume [cc]3 4. Retractable Antenna An antenna that you can retract Basically a dipole antenna with toploading (looks like a hat)$2 when you try to buy $0.1 when you are a company amazon.com 4 5. Stubby Antenna When you open a cap, you can see ahelical antenna. (looks like a spring) You dont have to retract. It isconvenient for users. What is stubby anyway?shutterstock.com 5 6. Ceramic Helical Antenna High permittivity Small antennasize6 7. Intenna Internal antenna: The antenna is in aphone. You cant see it. A phone case is strongly related toan intenna. 7 8. Intenna for 3G Phone A metal pattern is served as anantenna. 8 9. Triple-Band Antenna Intenna: internal antenna Resonance: 900, 1600, 1900 [MHz] empire.de9 10. PIFA Planar Inverted F AntennaSignal Input Radiator Original FromCoaxialCable PIFA10 Integrated PIFA 11. PIFA for Notebook 11 12. PIFA for Cell-Phoneantenova.com12 13. Current Distributions empire.de13 14. Antenna for Galaxy Nexus Can you point where the intenna isnow?14 15. Impedance Matching for Phone Chip capacitors and inductors are used to matching the antenna and circuit. 15 ham-radio.com 16. Apples Antennagate Death grip: when you touch a certainpart of an iPhone 4, your call may bedropped. Stainless steel frame as multi-bandantennas 16 17. Effect of Our Body to Phone Our body is a ground plane for aphone. That means our body affectsthe phone seriously. 17 18. SAR Measurement SAR: Specific Absorption Rate Your brain can absorb EM power.The SAR measures how much poweryour head does. 18 nearfield.org