With the continuous expansion of LTE network scale

TDD + FDD multi-mode and multi-frequency complex network has been widely used in the current network

and the optimization of inter-frequency handover is one of the important contents. Aiming at the existing problems of inter-frequency handover in the current network

this paper makes a comprehensive analysis of the reasons through the in-depth study of the handover principle and algorithm of LTE network

especially focuses on the analysis of the network and terminal problems in the handover measurement

puts forward reasonable optimization ideas and solutions. It has been verified by practice and has some reference significance for optimization work.