Tracking Efficiency Improvement According to Incident Beam Size in QPD-Based PAT System for Common Path-Based Full-Duplex FSO Terminals. - Siwoong Park; Chanil Yeo; Young Soon Heo; Ji-Hyoung Ryu; Hyun Seo Kang; Dong-Seon Lee; Jae-Hyung Jang (Sensors, 2022)