Patent ID: 8237519

Claim:
A metamaterial structure based filter apparatus, comprising: an unbalanced extended composite left and right handed (E-CRLH) metamaterial unit cell comprising: a first series inductor LR and a first series capacitance CL that in combination produce a first series resonance ω SE , a first shunt inductor LL and a first shunt capacitance CR that in combination produce a first shunt resonance ω SH , a second series inductor LR′ and a second series capacitance CL′ that in combination produce a second series resonance ω SE ′, and a second shunt inductor LL′ and a second shunt capacitance CR′ that in combination produce a second shunt resonance ω SH ′, wherein the first series inductor LR, the first series capacitance CL, the first shunt inductor LL, the first shunt capacitance CR, the second series inductor LR′, the second series capacitance CL′, the second shunt inductor LL′ and the second shunt capacitance CR′ are (1) coupled to form a symmetric cell structure for the E-CRLH unit cell where an input and an output of the E-CRLH unit cell have a common circuit structure, and (2) to have values that render ω SE and ω SH ′ to be substantially equal, and ω SH and ω SE ′, to be substantially equal.