A layered constant gradient acoustic ray tracing underwater positioning algorithm considering round-trip acoustic path
YAN Fengchi, WANG Zhenjie, ZHAO Shuang, NIE Zhixi, SUN Zhen, LI Weijia
Acta Geodaetica et Cartographica Sinica . 2022, (1): 31 -40 .  DOI: 10.11947/j.AGCS.2022.20210234