Microwave Dielectric Ceramics for Resonators and Filters in Mobile Phone Networks

• Published in: Journal of the American Ceramic Society Vol. 89; no. 7; pp. 2063 - 2072
• Main Authors: Reaney, Ian M., Iddles, David
• Format: Journal Article
• Language: English
• Published: Malden, USA Blackwell Publishing Inc 01.07.2006; Blackwell; Wiley Subscription Services, Inc
• Subjects: Applied sciences; Building materials. Ceramics. Glasses; Cell phones; Ceramic industries; Ceramic resonator oscillators; Ceramics; Chemical industry and chemicals; Dielectric constant; Dielectrics; Electrotechnical and electronic ceramics; Exact sciences and technology; Frequencies; Microwave communications; Microwaves; Mobile communications networks; Permittivity; Resonators; Tables; Technical ceramics; Resonator; Mobile phone; Filter; Microwave; Review; Dielectric ceramics; Electroceramics
• ISSN: 0002-7820; 1551-2916
• DOI: 10.1111/j.1551-2916.2006.01025.x

Temperature‐stable, medium‐permittivity dielectric ceramics have been used as resonators in filters for microwave (MW) communications for several decades. The growth of the mobile phone market in the 1990s led to extensive research and development in this area. The main driving forces were the greater utilization of available bandwidth, that necessitates extremely low dielectric loss (high‐quality factor), an increase in permittivity so that smaller components could be fabricated, and, as ever in the commercial world, cost reduction. Over the last decade, a clear picture has emerged of the principal factors, that influence MW properties. This article reviews these basic principles and gives examples of where they have been used to control microwave properties and ultimately develop new materials.