Because poor coverage is a serious impact on user perception

it is one of the most important issues for operators and one of the most important issues to be solved. In the past

the main sources of poor coverage were road test

user complaint and so on. In recent years

with the enhancement of large data acquisition and analysis ability

MR data analysis has also become one of the most important means of poor coverage discovery. Taking a dense urban area as an example

this paper introduces the whole process of large data parsing

large data location

poor coverage discovery and optimization suggestions. The method of this paper provides experience for the actual network planning optimization.