Designing Digitally Tunable Microwave Filter MMICs

Tunable filters are a vital component in broadband receivers and transmitters for defence and test/measurement applications. The very low component parasitics that can be achieved on an MMIC (Microwave Monolihic Integrated Circuit) allow the reailsation of compact, low-cost tunable microwave filters. This technical briefing discusses the design, realisation and achievable performance of digitally tunable filter MMICs.