LTE LTE

LTE

2G/3G

2G/3G

2G/3G 2G/3G

2G/3G

2G/3G

2G/3G

2G/3G 2G/3G 2G/3G

2G/3G 2G/3G 2G/3G 2G/3G

LTE

OverviewThe LTE network at the initial phase covers only hot spots and is limited in continuous coverage. Single radio voice call continuity (SRVCC) or enhanced SRVCC (eSRVCC) enables subscribers to continue their ongoing calls when they move from an LTE network to a 2G or 3G network.

A subscriber initiates a handover from an LTE network to a 2G/3G network while placing an LTE-initiated call on hold.

A subscriber initiates a handover from an LTE network to a 2G/3G network after being alerted by an incoming call. The calling subscriber initiates such a handover when the called subscriber is being alerted.

Any participant in a multiarty call initiates a handover from an LTE network to a 2G/3G network.

SRVCC

Handover during roaming

2G/3G network

LTE network

Uninterrupted calls

Handover delay >1s

2G/3G network

LTE network

Uninterrupted calls

Handover delay