As the electromagnetic environment becomes more populated, frequency-agility and narrow operating bandwidths are becoming highly desirable characteristics for bandpass filters in RF front ends. As such, bandpass filters having a high unloaded quality factor (Qu) are a requirement for maintaining low insertion loss and minimum noise figure. In addition, size and cost are also important considerations.
While microstrip or stripline filter technology offers a low cost solution within a small footprint, their unloaded quality factor, Qu, is limited by system losses rendering them inadequate for many applications. When high-selectivity is required, metal waveguide technology is employed. While this technology offers very high unloaded quality factors in the thousands, their size and weight make them prohibitive in many applications. In addition, they are much more costly than their printed circuit counterparts. MEMtronics Filter Innovation Technology (MFIT) address’ the gap between microstrip or stripline and metal waveguide that offers very high quality factors approaching waveguide, with the size and cost advantages of printed circuits.
We are actively engaged in the development of filters for a variety of applications in the electromagnetic spectrum. As demonstration vehicles, we have developed MFIT prototypes in X-band and Ka-band. Custom filters to meet specific user requirements are also possible from 2 GHz through 50 GHz, with passband bandwidths ranging from 0.5% to 10%, in implementations with 2-5 poles of filtering.
Filter platform criteria for our prototype designs is extremely low-loss (performance), planar (size and weight) and a precise, repeatable manufacturing process (cost). To address these criteria, MEMtronics has developed miniature waveguide technology that combines advantages of planar printed circuits that are compact, light, easy to fabricate, flexible, and cost effective while preserving the advantages of conventional metallic waveguides, namely, complete shielding, low-loss, high quality-factor and high power-handling capability.