A study on a RF filter of IMT-2000 terminal using coupled rectangular microstrip loop resonators

In this paper, we analyzed RF filters of IMT-2000 terminal using coupled rectangular microstrip loop resonators and compared this with numerical analysis. The characteristic equations of the resonators are derived and the resonators analyzed with two-port networks. We confirmed that the resonance length varied according to substrate height, dielectric constant, line width, etc. in the rectangular loop resonator with and without a gap. Also we analysed the filters which are composed of coupled rectangular microstrip ring loop resonators. The coupling structure is the cross coupled rectangular resonator. The derived characteristics equation of the filters that is composed of a two port ABCD matrix. We obtained the coupling coefficient for the coupled resonators. In this papers, small size filter with low loss using microstrip loop resonators is presented