Intersystem change between different radio access networks

Abstract

A wireless terminal can communicate with two radio access networks (RAN) (304, 306) of different types. The wireless terminal can register simultaneously with a RAN of the first type and a RAN of the second type and can wirelessly connect to a RAN of either the first type or the second type in a connected state. The wireless terminal when registered with both a first RAN and a second RAN and when wirelessly connected to the first RAN in the connected state, receives a mobility signal via the first RAN indicating a RAN of the second type and, in response to receiving the mobility signal and in response to being so registered with the first RAN and second RAN, transmits an access trigger signal (417). The access trigger signal indicates that the wireless terminal is to be connected to the second RAN in the connected state.

Dependencies are inferred from the claim text.