EXXELIA, A EUROPEAN SOURCE OF HIGH Q FACTOR DIELECTRIC RESONATORS
Exxelia presents its new dielectric resonator, the E7000 series. The series has been designed for high-end filters where Q factor is critical, especially in space or military applications.
Operating frequencies in wireless communications have shifted towards high frequency band and thus frequencies higher than 1 Ghz are now commonly utilized. In addition, the microwave frequency spectrum becoming severely crowded and sub-divided into many different frequency bands, designers are systematically looking for resonators giving them a narrow bandwidth with smaller size.
Dielectric resonators are designed to replace resonant cavities in microwave functions such as filters and oscillators. Exxelia Temex, daughter company of Exxelia Group, has developed with support of ESA and CNES, a new high-end dielectric material, E7000 series, designed for high-end filters where high Q factor is requested.
E7000 is Ba-Mg-Ta materials based that combines an ultra-high Q factor and the possibility to get all the temperature coefficients upon request. E7000 provides high-performance requested for space use in the frequency range 5 to 32 GHz, and guarantees up to Qxf > 250 000 at 10GHZ.
Typical applications: Satellite multiplexing filter devices, radio links for communication systems (LMDS),
Film capacitor series keeps its cool even at 150°C
The Exxelia Dearborn 880P series of metalised Polyphenylene Sulfide (PPS) Film Capacitors is designed to keep cool when things get hot. With an operating temperature range of -55 to +150°C, they experience no derating for DC operations and none in AC operations up to +125°C. This enables them to function at full capacity in extreme heat applications. The ability to operate at such high temperatures can eliminate the need for a cooling system within the design, thus reducing overall design time, weight and space. PPS is a high-temperature, low-loss dielectric film used in the 880P series of wrap-and-fill capacitors. This allows them to feature superior electrical characteristics over an extremely wide temperature range and maintain excellent capacitance stability in one rugged, lightweight package. It performs consistently well in commercial applications such as in power supplies and in more demanding applications, such as in avionics, on a congested control or instrumentation panel. The series features a capacitance range of 0.0047 to 10.0µF and voltage ratings from 50 to 400VDC with precision tolerances as low as ±¼% through ±10% yielding greater accuracy of capacitance. It is also a customisable unit with voltage maximums of 700 – 800VDC at 125°C maximum (higher voltages are available at reduced capacitance). Made in the USA, the units are highly durable and capable of withstanding a five-pound pull force on lead axis. They are non-polar and demonstrate low loss factor, good voltage breakdown strength and high insulation resistance (low leak current) – and are completely stable over normal temperatures, voltages and frequency ranges. These characteristics allow the 880P series capacitors to deliver high performance in a variety of applications such as DC timing circuits, low- to high-frequency AC applications, and pulse or energy discharge uses. Additionally, the package has axial leads with moisture-resistant, flame-retardant epoxy end seals and an outer tape covering for maximum performance.
New Invar Tuning Elements with Self-Locking System
Working frequencies in Space applications are shifting to Ka, Ku or even Q band, while cavity filters are undergoing the general trend towards miniaturization: this context calls for a much more precise and stable tuning element now offered by Exxelia Temex, daughter company of Exxelia, through their last innovative and unrivalled solution to incorporate a self-locking system into their Invar Tuning Elements. Invar-36 is a unique Iron-Nickel alloy (64 % Fe / 36 % Ni) sought-after for its very low coefficient of thermal expansion. With 1.1 ppm. K–1 between 0°C and 100°C, Invar-36 is about 17 times more stable than Brass which is the most traditional and common alloy Tuning Elements are made of. The working temperature range in Space is so wide that this property becomes essential for a reliable and stable cavity filter tuning. Self-locking system is a technology commonly used on Tuning Element made of Brass or other soft “easy-to-machine” alloys but is innovative and pretty advanced when applied to hard and tough Invar 36. The design consists of two threaded segments separated by two parallel slots. After cutting both parallel slots, the rotor is compressed in its length in order to create a plastic deformation. Thus, an offset is induced between the two threaded segments which generates a constant tensile stress in the rotor from the moment threaded segments are screwed.