A compact microstrip Rotman lens design

Rotman lenses have long served as analog beam forming networks (BFNs) to support linear scanning arrays. However, most lens designs have large electrical size which limits their uses in compact transceiver systems. In this paper, we aim to design a compact lens structure by folding the lens into two layers, and using coupling slots as transition. The proposed designed structure will reduce the overall dimensions of the conventional Rotman lens by 50%.