Design of Compact BranchlineBalun

Abstract

This paper present the compact branch line balun to operate at the frequency range of 2.4GHz. The compact branchlinebalun is designed using the substrate material with the dielectric constant of FR4 material. The proposed balun is designed using different transmission lines. Thus the balun should achieves -3dB power division and 1800 phase differences between the outputs. The main objective of this design focuses on size reduction. To reduce the size, A balun is realized using the equivalent T-shape structure. After the reduction techniques the implemented size of the balun is 29.41x44.32 mm2 achieves 35% of size reduction. Thus the measured S11 are -23 dB and the S21,S31 remains -3dB and provide 1790 phase difference between the outputs at the frequency of 2.4GHz.