Microwave Journal
www.microwavejournal.com/articles/17412-nuhertz-enhances-design-of-folded-hairpin-resonator-filters

Nuhertz enhances design of folded Hairpin resonator filters

April 20, 2012

FilterSolutions™ and QuickFilter™ synthesis programs from Nuhertz Technologies introduce enhanced techniques for designing Hairpin Resonator or Ring Resonator filters. In conjunction with electromagnetic simulation tools from AWR Corp. and Sonnet Software, optimized cross-coupled circuits are used to minimize the use of circuit board space and narrow the passband. This technique allows the resonators to be folded inside the Hairpin structure, solving for electromagnetic interaction.

Hairpin Resonator designs can meet geometry limitations without needing vias between layers.

Internal circuit tuning may be used to fine-tune to the desired response. Optimization may be accomplished by exporting the Nuhertz synthesized design to transmission-line circuit optimization programs, such as AWRCorp’s Microwave Office™. Nuhertz programs create AWR tuning equations to enforce geometry limitations.

Electromagnetic optimization is usually necessary to account for interaction between the conductor segments of the Hairpin, as they cannot be modeled in circuit analysis. The electromagnetic optimization of the design may be accomplished using Sonnet Software’s em® Port Tuning optimization technique; AWR’s Axiem™ extraction, or other third-party extraction optimization.