A Novel 2-D 3×3 Nolen Matrix for 2-D Beamforming Applications - Ren, Han; Zhang, Hanxiang; Jin, Yuqi; Gu, Yixin; Arigong, Bayaner (IEEE transactions on microwave theory and techniques, 2019)
Keywords: Antenna feeding network; Array signal processing; beamforming network; Butler matrices; Couplers; Delays; flexible phase differences; microwave device; phased array; Phased arrays; Transmission line matrix methods