The LTE resident-ratio index reflects the proportion of the resident time of LTE users in LTE network to the total length of resident time in 2 G/3 G/4 G network. The higher LTE resident ratio

the more users use LTE services

experience high speed and low latency performance of LTE services

and improve user perception. Recently

we tested the test of closing the 2 G redirection switch to enhance the LTE residentratio in the current network

but it is found that CSFB business will be affected. This paper analyzes and studies this in order to prevent the negative effect of improving the LTE resident ratio.