By Cameron Sheth and Kyle Chang
Filters are ubiquitous throughout RF systems, yet they have not seen the same degree of advancements (e.g. size reduction and high-frequency operation) that have been made to the rest of the RF signal chain. Current filter solutions consume a large volume of a system’s overall footprint and are susceptible to process and lot-to-lot variation. Due to the custom nature of filter requirements, they are often designed in-house, consuming valuable engineering time and resources through multiple iterations of cascade analysis and subsequent design.
Until recently, MMIC has not been considered a viable technology for filter development due to misconceptions about the technology including development time, cost, suitability for custom solutions (due in part to the aforementioned time and cost), and the focus on traditional filter metrics, such as Q factor. In reality, MMIC design cycles are short due to fast wafer fabrication cycles and accurate first-pass design success. Combined with the high-volume production capability of MMIC technology, this has the added benefit of reducing the cost of custom designs at volume.
This white paper aims to discuss what Marki Microwave® contends to be the key metrics of a modern competitive filter technology, how these are achieved through a GaAs MMIC process, and the capabilities of MMIC filters that have been demonstrated thus far. Together with the companion design tool that has been developed, this offers a fast, accurate and trustworthy way of developing filters without consuming large amounts of customer and vendor design resources.