1. Title: Application of Piezoelectric Ceramics in Communication system Dr. & Prof. Chun-Huy Wang Electronical Engineering, Nan-Jeon Institute of Technology Multimedia English Teaching PP.

2. ＜ Electronic Ceramics ＞ Ferroelectric Pyroelectric Piezoelectric Dielectric Dielectric Property Piezoelectricity Pyroelectricity Ferroelectricity

3. What can piezoelectric ceramics do?

4. Piezoelectricity Mechanical and electrical energy conversion phenomena, discovered by France Scientist Pierre and Jacques Curie brother in 1880. Direct Piezoelectric Effect Mechanical Electrical Converse Piezoelectric Effect

5. Piezoelectricity

6. Piezoelectric Ceramics  (perovskite) 結構，化學式為 Pervoskite structure, with the chemical formula as ABO 3 e.g. : BaTiO 3 cornal center face center

7. Piezoelectric Ceramics cornal center face center

8. Domain and domain boundaries of polycrystalline BaTiO 3 -(Jaffe et al. 1971), (left)domain structure of unpoled ferroelectric ceramics – (right) graphical representation

9. Poling  Poling is the final process in the fabrication. Initially, unpoled ceramics have no piezoelectricity because the piezoelectric tensors of the grains are randomly oriented.  During the poling process, ferroelectric switching occurs and creates non zero overall piezoelectric tensors.

10. (3) after poling (1) unpoled (2) during poling

11. P~E Curve Domain Wall Movement

12. P~E curve vs Voltage Applied

13. Communication Applications  Piezoelectric ceramics used as the resonator and filter in communication system with frequency lower than 100MHz 。  For frequency higher than 100MHz ， the Surface Acoustic Wave (SAW) devices is used.

14. Communication Applications  The ceramic filter and resonator are made of high stability piezoelectric ceramics that functions as a mechanical resonator.  The frequency is primary adjusted by the size and thickness of the ceramic element. Typical application includes TVs, VCRs, telephones, remote controls and radios.

15. Communication Applications

16. Operating Principle and feature of each filter

17. Ceramics Resonator  Resonator is the basic frequency control component, the piezoelectric filter is composed by the piezoelectric resonator.

18. Ceramics Resonator

19. Ceramic Filter Monolithic Filter (used for low frequency)

20. Ceramic Filter

21. SAW Resonator and Filter  SAW : Surface Acoustic Wave In natural world, SAW can create by earthquake.  In engineering, SAW can create by piezoelectric effect.

22. SAW Resonator and Filter

23.  Advantages of SAW  High Sensitivity  High Accuracy  Passive  Wireless  Digitalized  Mass Production  Many Application Possibilities

24. SAW Resonator and Filter Two Port ResonatorOne Port Resonator

25. SAW Resonator and Filter Applications of SAW Filter  GSM Applications of SAW Filter  PCS & CDMA

26. SAW Resonator and Filter Applications of SAW Resonator

27. Thank you For Listening ！