Concurrent Triple Band Complex to Real Impedance Transformer for RF Applications

This work introduces a novel technique to simultaneously match any three uncorrelated Frequency Dependent Complex Loads (FDCLs) to a real source. Its adaptability allows it to transform any load combination for any frequency ratio. Since all the transmission lines used in the design have a characteristic impedance of 50 Ohms, there isn’t any fabrication related restrictions of the structure. In the proposed scheme, a branched stub adds susceptance to the load admittance such that the modified loads for all the three frequencies can be moved to g=1 circle, hence matching the real part of the admittance using a single series transmission line. The left over susceptances are cancelled through another branched stub. Two triple band prototype matching networks have been presented. All the structures are fabricated on ROGERS RO4003 substrate with dielectric constant, er=3.38 and height, h=20 mils. The simulated and the measured results are in good accordance.