Inland areas have cellular network coverage, but sea areas have poor natural environments, making base station location difficult and costly. This paper studies a Marine network coverage scheme based on non-line-of-sight microwave transmission technology to address the contradiction between Shanghai's service demand and station construction difficulty. Key factors affecting coverage are analyzed, and technical schemes are proposed, including frequency planning, base station power, antenna optimization,signal protection. Based on technical principles and marine traffic distribution, an integrated “ocean coverage” construction scheme is formulated to achieve three-layer network services in coastal, offshore, and far-sea regions. The scheme has been implemented, supporting marine economic projects and generating economic and social value.