Left-handed band pass filter realized by coupled negative order resonators

A left-handed metamaterial-based multi-pole filter is realized by coupled resonators that exhibit negative order resonant modes (in this case, m = -1) . By using coupling elements at the input, output, and inter-stage section, a Chebyshev response with narrow or moderate bandwidth can be realized. Owing to the symmetric structure, filter design can be achieved that includes all right-handed parasitic elements. Circuit simulation and 3 D EM simulation are used for design and the left-handed two-pole filter is implemented by LTCC. The slow wave nature of left-handed resonance makes the filter very compact. The dimensions of the experimental filter are 4.9 mm by 2.2 mm by 0.5 mm. The insertion loss is about 3 to 5 dB in the 2.4 GHz band.