Why can't the phone connect to a specific LTE frequency band on its own?
In a network environment that only includes LTE, support for IMS (VoLTE) is necessary to enable calling functions. The registration mechanism for such networks is quite specialized and requires a series of different parameters, necessitating specific adaptations for these networks.
In contrast, network environments that include 4G, 3G, and 2G networks do not have IMS restrictions and generally support CSFB (Circuit-Switched FallBack, where calls are routed through 3G/2G when on 4G). The registration mechanisms across different carriers are identical and do not require separate adaptation.
In contrast, network environments that include 4G, 3G, and 2G networks do not have IMS restrictions and generally support CSFB (Circuit-Switched FallBack, where calls are routed through 3G/2G when on 4G). The registration mechanisms across different carriers are identical and do not require separate adaptation.
Does it help?
Yes
No