Implementation of a Planar 8×8 Microstrip Butler Matrix in X Band

A planar 8×8 microstrip Butler matrix in X Band is proposed in this paper. It is a planar beam-forming network with the advantages of compact size, low cost and ease of fabrication. Three-branch line couplers used to form crossover elements which are adopted to have a planar structure, and phase shifters based on crossovers are designed to get good transmission and phase performances. The results of measurement of the Butler matrix makes it very attractive for planar multi-beam antenna applications

Keywords:

Butler Matrix , microstrip , coupler , plannar