Design method of a dual band balun and divider

This paper presents the design method and performance characteristics of a dual band balun. The design method for dual band balun is based on the lumped element equivalent circuit of quarter-wave transformer. By employing the proposed configuration and the derived formulas, dual band balun are designed, simulated, and manufactured. The proposed design method and equivalent circuit can make it easy to adapt to designing dual band balun and divider of ceramic multi-layer chip type. The dual band balun and divider are applied to wireless communication system.