This paper presents a design methodology of wide-band bandpass filters based on short-circuited multi-conductor transmission lines with bonding wires between alternated strips. General design guidelines, based on analytical equations, are derived and a left-handed behaviour of the multiconductor structure is inferred and studied. Analytical equations are assessed by means of full-wave electromagnetic simulations and experimental work. A very good agreement between theoretical results and measurements is achieved, that allows both the design and performance analysis of filters without the need for costly electromagnetic simulations. In addition, the equations presented yield a compact design of the filter with a left-handed behavior.
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