OOptics Letters3/30/2026High security key accompaniment transmission scheme based on constellation flat coding over seven core fiberzining pan·wen han·Jianxin Ren·Shuaidong Chen·Yaya Mao·xiumin song·Ying Li·Feng Ryan Wang·J. P. Wang·Mengtong Yin·Qiying Wang·Xin Ge·Bo LiuRead at Optics LettersTagsgraph theory and CDMA systemsElectrical and Electronic Engineering