This paper briefl y reviews the rise of 4 G communication system

leads to the concept of 5 G

summarizes and analyzes its key technologies

and compares the difference between 4 G and 5 G in terms of index capability

technology comparison and application scenarios

so as to predict the future development direction of 5 G network. We hope to provide some feasible basis for mobile communication personnel through the analysis of some key technologies of 5 G mobile communication and the difference comparison with 4 G.