Patent ID: 11930549
Assignee: SHARP KABUSHIKI KAISHA
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. A User Equipment (UE) comprising:
control circuitry; and
transmitting and receiving circuitry, wherein:
the control circuitry is able to perform a second emergency call attempt in an Evolved Packet System (EPS) in a case of a failure of a first emergency call attempt in a 5G system (5GS),
the transmitting and receiving circuitry receives a Protocol Data Unit (PDU) SESSION ESTABLISHMENT REJECT message as the failure of the first emergency call attempt,
the control circuitry determines whether the system in which the UE performs the second emergency call attempt is the EPS or the 5GS, based on a cause value indicating a reason that the first emergency call attempt is rejected,
the control circuitry uses a first access network for the first emergency call attempt, and
the control circuitry uses a second access network for the second emergency call attempt.