Communication fallback in 5G systems and methods

At least one computer-readable medium, excluding transitory signals and containing instructions, that when executed by a processor, performs a method in a mobile device for performing Evolved Packet System (EPS) fallback from a 5G system to a Evolved Packet Core (EPC) system, the method comprising:

• detecting a communication at the mobile device;
• determining, based at least in part on 5G indicator data of the mobile device, whether the mobile device supports the communication over new radio,
• wherein the 5G indicator data is stored in a memory of the mobile device and includes information about whether the mobile device supports communication over 5G New Radio;
• determining, based at least in part on the 5G indicator data, whether a base station supports the communication over new radio;
• directly in response to determining that either one of the mobile device or the base station does not support the communication over new radio:
• generating and transmitting an EPS fallback service request from the mobile device to the base station,
• wherein the EPS fallback service request instructs the base station to initiate a fallback procedure from the 5G system to the EPC system,
• whereby the fallback procedure is triggered, based on the 5G indicator data, to reduce setup time for the mobile device in response to the detecting of the communication, and
• whereby, when the mobile device detects the communication, instead of immediately sending a SIP INVITE message to the base station, the mobile device automatically triggers the EPS fallback service request to fall back to the EPC system by connecting to an available 3G or 4G base station.

A method in a base station for performing Evolved Packet System (EPS) fallback from a 5G system to a Evolved Packet Core (EPC) system, the method comprising:

• receiving an EPS fallback service request from a mobile device to the base station,
• wherein the mobile device is associated with a 5G support indicator,
• wherein the 5G support indicator includes information about whether the mobile device, or both the mobile device and the base station, support communication over 5G New Radio,
• wherein the mobile device determines, based at least in part on the 5G support indicator, whether the mobile device supports communication over new radio,
• wherein the mobile device determines, based at least in part on the 5G support indicator, whether the base station supports communication over new radio,
• wherein the EPS fallback service request is generated by the mobile device directly in response to determining that either one of the mobile device or the base station does not support communication over new radio,
• wherein the EPS fallback service request instructs the base station to initiate a fallback procedure from the 5G system to the EPC system,
• whereby, the fallback procedure is triggered, based on the 5G support indicator, to reduce setup time, and
• whereby, when the mobile device initiates a communication, instead of immediately sending a SIP INVITE message to the base station, the mobile device automatically triggers the EPS fallback service request to fall back to the EPC system by connecting to an available 3G or 4G base station.