1. Broadband Printed Dipole Antenna With a Step- Shaped Feed Gap for DTV Signal Reception Yun-Wen Chi, Kin-Lu Wong, and Saou-Wen Su IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION, VOL. 55, NO. 11, NOVEMBER 2007 Presenter ： Tai-hung Lin

2. 2 Outline Introduction Antenna Design and dimensions Experimental Results and Discussion Conclusion

3. 3 Introduction Promising planar antenna types Planar inverted-F antennas(0.25λ, PIFAs). Patch antenna. Printed monopoles / dipoles antenna. Chip antenna( plastic, foam, ceramic bases) Slot antenna (0.5λ). Loop antenna (1λ).

4. 4 Antenna design and dimensions(1) Rectangular shape Size : 20 × 227 mm 2. Two asymmetric radiating portions of arm 1 and arm 2.

5. 5 Antenna design and dimensions(2) DTV (Digital television) bandwidth 470 ~ 806MHz. Printed dipoles antenna ( 約 0.5λ). WLAN 波長 ( 空氣 ) 天線長度為 267mm (L+2W) /λ o = 0.418λ

6. 6 Experimental Results and Discussion(1) Bandwidth: 340MHz, 53%

7. 7 Experimental Results and Discussion(2) Bandwidth: 510~680MHz, 28.5%

8. 8 Experimental Results and Discussion(3)

9. 9 Experimental Results and Discussion(4)

10. 10 Radiation patterns (2-D)

11. 11 Antenna gain and radiation efficiency Antenna gain :1.5 to 2.8 dBi Radiation efficiency : 60% ↑

12. 12 Conclusion A broadband printed dipole antenna with a step-shaped feed gap for DTV signal reception in the 470–806 MHz band has been proposed. The obtained impedance bandwidth (2.5:1 VSWR) reaches 340 MHz (470–810 MHz) or about 53% centered at 640 MHz. The wide operating band, stable radiation characteristics (60%↑) have also been obtained.

13. 13 作者 : 郗韻文 (Yun-Wen Chi) 手機天線設計競賽 - 2006 、 2008- 冠軍 2007- 佳作 http://www.mobilehero.com/

14. 14 Thank for your attention!