A Novel Meandered Coupled-Line Tri-Band Impedance Matching Network

This paper proposes a novel design of a quarter-wave meandered coupled line based tri-band impedance transformer. The design utilizes cascade of two existing dual-band impedance transformer to achieve tri-band functionality. The proposed design matches a real load to a conventional 50n source at three arbitrary frequencies of IGHz, 2.4GHz and 3.8GHz. The design uses the concept of matching at a reference frequency that is common to both dual band matching sections. A prototype fabricated on FR4 shows good agreement between the simulated and measured results.