Helical ceramic resonator structures

Combline filters using periodically loaded resonators

“…When a modified chemical vapor deposition (MCVD)-fabricated type of SMF is dipped into an enchant solution of hydrofluoric acid (HF) buffered in ammonium fluoride (NH 4 F), the etching rates in the core and in the cladding are unequal, due to the different glass composition in each region [2][3][4][5]. This results in a self-centered conical proturbance that is directly related to the doping profile.…”

“…However, the dielectric-loaded resonator has higher cost and poor spurious response. A method to make a much smaller resonator by using a periodic structure, proposed [2], employs the slow-wave property of a periodic structure to reduce the size of resonator. This method also has potential to improve the performance of the resonator.…”

Advances on Microwave Ceramic Filters for Wireless Communications (Review Paper)

“…This was achieved with the use of automated milling or laser etching tools to modify the geometry of both the ceramic and plating and hence the cost of the generic structure and associated equipment was spread over many applications. In [17] a helical ceramic resonator design was described and a sample filter structure based on this type of resonator was presented. The helical resonator structure was produced using standard ceramic…”

“…Cross-sectional view of two ceramic resonator structures: (a) conventional coaxial. (b) helical[17].…”

Bandpass filters using periodically loaded combline resonators

“…Analysing the corrugated conductor structure, we find that these solutions for the corrugated conducting surface under the condition that period p Ͻ are the same as those of the dielectric coated conducting plane [2]. Filters loaded with periodic helix resonator structures are miniature filters [3]. Therefore, using periodic structures to replace the dielectric materials is a method to improve the performance of the resonator.…”