Abstract: A method to establish and activate an MA PDU session for data transmission over a selected access is proposed. UE initiates a UE-requested PDU session establishment procedure. Once the UE receives a PDU SESSION ESTABLISHMENT ACCEPT message with ATSSS container IE, the UE can consider the MA PDU session has been activated and user plane resources are successfully established on the selected access. A method to convert an SA PDU session to an MA PDU session for data transmission over a selected access is proposed. UE initiates a UE-requested PDU session modification procedure. Once the UE receives a PDU SESSION MODIFICATION COMMAND message with ATSSS container IE, the UE can consider the MA PDU session has been converted from the SA PDU session and user plane resources are successfully established on the selected access.

Abstract: A method of enhanced handling of a Forbidden SNPN list by a UE is proposed. When the UE registers to a first SNPN using credentials supplied by a second SNPN and receives a rejection from the network, the UE adds an entry of the first SNPN into one of the forbidden SNPN lists, and also creates an association between the first SNPN and the second SNPN. As a result, the UE is refrained from registering to the first SNPN using the credentials supplied by the second SNPN as long as the first SNPN entry remains in the forbidden SNPN list. However, the UE is allowed to register to the first SNPN using credentials supplied by other SNPNs.

Abstract: A method for Procedure Transaction Identity (PTI) error handling on 5G Session Management (5GSM) procedures is proposed. If a User Equipment (UE) receives a PDU SESSION AUTHENTICATION COMMAND or PDU SESSION AUTHENTICATION RESULT message in which the PTI value is an assigned value, the UE transmits a 5GSM STATUS message including 5GSM cause #81 “invalid PTI value”. If the UE receives a PDU SESSION ESTABLISHMENT ACCEPT or REJECT message, a PDU SESSION MODIFICATION COMMAND or REJECT message, or a PDU SESSION RELEASE COMMAND or REJECT message in which the PTI value is an unassigned value, the UE ignores the received message. If the UE receives any 5GSM message in which the PTI value is a reserved value, the UE ignores the received 5GSM message.

Abstract: In 5GS, Single-Network Slice Selection Assistance Information (S-NSSAI) based backoff (BO) timers (T3584/T3585) can be applied to either the registered PLMN or all the PLMNs based on a 5GSM congestion re-attempt indicator. For a specific PDU session, the corresponding BO timer applied to the registered PLMN and the BO timer applied to all PLMN can be both running concurrently. It is proposed for a UE to stop both the BO timer applied to all the PLMNs and the BO timer applied to the registered PLMN, if running, in all the following scenarios: 1) Receiving a PDU session release command without a BO timer, 2) Receiving a PDU session release command with 5GSM cause #39, 3) Receiving a PDU session modification command, 4) Receiving a 5GSM message with a 5GSM congestion control BO timer value, and 5) Receiving a PDU session authentication command.

Abstract: A method of handling multi-access (MA) Protocol data unit (PDU) session establishment procedure with multiple PDU SESSION ESTABLISHMENT ACCEPT messages by a UE is proposed. In one novel aspect, upon receiving a second PDU SESSION ESTABLISHMENT ACCEPT message over the other access, the UE deletes the stored authorized QoS rules, and deletes the stored authorized QoS flow descriptions and the stored mapped EPS bearer contexts if they are included in the PDU SESSION ESTABLISHMENT ACCEPT message. In another novel aspect, upon receiving a second PDU SESSION ESTABLISHMENT ACCEPT message over the other access, the UE performs a local release of the MA PDU session if any value of the selected PDU session type, selected SSC mode, 5GSM cause, PDU address, S-NSSAI, DNN IEs in the PDU SESSION ESTABLISHMENT ACCEPT message is different from the corresponding stored value.

Abstract: A method of handling mapped EPS bearer context with duplicate EPS bearer ID (EBI) for 5GS to EPS inter-system change enhancement is proposed. UE is provided with a mapped EPS bearer context IE by the network to create a new mapped EPS bearer associated with a PDU session. UE detects collision of the new mapped EPS bearer—it has the same EBI as an existing EPS bearer. Upon successfully process the create request, UE either replaces the existing EPS bearer with the new mapped EPS bearer, or deletes the EPS bearer with duplicate EBI by explicit signaling to the network. As a result, when inter-system change from 5G to EPS happens, there is no EPS collision.

Abstract: A method of handling invalid PDU session during handover procedure between non-3GPP access and 3GPP access in a mobile communication network is proposed. A UE establishes a PDU session over a first RAT, and then tries to handover the PDU session from the first RAT to a second RAT. However, at the network side, the PDU session over the first RAT does not exist anymore and the network considers the PDU session to be invalid. The network thus sends a PDU session establishment reject message back to the UE, with a 5GSM status message cause value #54 indicating “PDU session does not exist”. At the UE side, the PDU session over the first RAT is still valid (e.g., not inactive). In order to resynchronize with the network, the UE performs a PDU session release procedure to release the PDU session over the first RAT.

Abstract: A method of defining ATtention (AT) commands for supporting Service and Session Continuity (SSC) mode 2 and SSC mode 3 of 5G Protocol Data Unit (PDU) session operations is proposed. The AT command can be a notification of an unsolicited result code +CGEV: NW PDN DEACT, +CGEV: NW MODIFY, or +CGEV: ME PDN ACT, or a configuration command +CGDCONT with additional 5G parameters. Additional 5G parameters include an SSC, an old CID, a change reason and a PDU lifetime for the purpose of communicating information regarding the request of PDU session anchor relocation.

Abstract: A method of handling multi-access (MA) Protocol data unit (PDU) session under inter-system change is proposed. An MA PDU session uses one 3GPP access network or one non-3GPP access network at a time, or simultaneously one 3GPP access network and one non-3GPP access network. The UE and network can support Access Traffic Steering Switching and Splitting (ATSSS) functionalities to distribute traffic over 3GPP access and non-3GPP access for the established MA PDU session. Upon intersystem change from 5GS to EPS over the 3GPP access, the 3GPP part of an MA PDU session is transferred to a PDN connection, and the non-3GPP part of the MA PDU session is released. The QoS flows of the MA PDU session over both 3GPP access type and non-3GPP access type are transferred to the EPS bearer contexts of the corresponding PDN connection.

Abstract: A control circuit and a control method for a power converter are provided. The power converter includes a plurality of resonant tanks and a plurality of switches disposed between an input terminal and an output terminal. The switches correspond to a first mode and a second mode, respectively, and the control circuit includes a first switch control circuit, a first zero current detection circuit, a second zero current detection circuit, a first switch off detector, a modulation time calculation module, a second switch control circuit, a third zero current detection circuit, a fourth zero current detection circuit, and a second switch off detector. The control circuit uses a plurality of zero current detection circuits to perform time modulations on a plurality of rectifier switches in the switches.

Abstract: In a first novel aspect, UE receives a mapped EPS bearer context IE during a PDU session establishment or modification procedure. UE diagnoses whether an operation error occurs for a mapped EPS bearer context. If so, UE deletes the mapped EPS bearer context with a 5GSM cause. In a second novel aspect, UE receives a QoS flow description IE during a PDU session establishment or modification procedure. UE diagnoses whether an operation error occurs for a QoS flow description. If so, UE either rejects the modification command or deletes the QoS flow description with a 5GSM cause. In a third novel aspect, UE receives a QoS flow description IE during an EPS bearer activation or modification procedure. UE diagnoses whether an operation error occurs for a QoS flow description. If so, UE includes an ePCO/PCO IE with a 5GSM cause in an activation or modification accept message.

Abstract: A control circuit and a control method for a power converter are provided. The power converter includes a plurality of resonant tanks and a plurality of switches disposed between an input terminal and an output terminal. The switches correspond to a first mode and a second mode, respectively, and the control circuit includes a first switch control circuit, a first zero current detection circuit, a second zero current detection circuit, a first switch off detector, a modulation time calculation module, a second switch control circuit, a third zero current detection circuit, a fourth zero current detection circuit, and a second switch off detector. The control circuit uses a plurality of zero current detection circuits to perform time modulations on a plurality of rectifier switches in the switches.

Abstract: A method of supporting IMS signaling over EPS bearer or QoS flow upon inter-system change between EPS and 5GS is proposed. When inter-system change from 5GS to EPS occurs, a PDU session is converted to a PDN connection having multiple EPS bearers. The EPS bearer mapped from the QoS flow that is used for IMS signaling in 5GS is the EPS bearer for IMS signaling in EPS. When inter-system change from EPS to 5GS occurs, a PDN connection is converted to a PDU session having multiple QoS flows. The QoS flow that is associated with the default QoS rule is the QoS flow for IMS signaling in 5GS, regardless of which EPS bearer is used for IMS signaling in EPS.

Abstract: A method of handling QoS error in an evolved packet system (EPS) session management (ESM) procedure to support interworking from EPS to 5G system (5GS) is proposed. A UE receives 5GSM parameters of QoS rule(s) and/or QoS flow description(s) included in a PCO/ePCO IE in an ESM message for performing a QoS operation. During the ESM procedure, only 5G QoS parameters related to the current EPS bearer been activated or modified are allocated and sent to the UE via PCO/ePCO. Otherwise, an operation error may occur for the QoS operation. Accordingly, the operation error is detected by the UE before intersystem change from S1 mode to N1 mode happens and the UE indicates such error to the network with a cause value.

Abstract: A PDU session status information element (IE) is used to bi-directionally synchronize the state of a multi-access (MA) Protocol data unit (PDU) session between UE and NW. In the downlink, the PDU session status IE is included in a 5GMM message sent from NW to UE over an access type, and it indicates the user plane resources are NOT established at NW side on the access type the 5GMM message is sent over. For MA PDU sessions having user plane resources established in the UE side only on the access type the 5GMM message is sent over, the UE performs a local release of those MA PDU sessions. For MA PDU sessions having user plane resources established in the UE side on both access types, the UE performs a local release on the user plane resources on the access type the 5GMM message is sent over.

Abstract: Aspects of the disclosure provide methods and apparatuses. The method can include receiving, at a user equipment (UE), system information broadcast from a base station which may be shared by one or more PLMNs and SNPNs, the system information including an indication of whether accessing an SNPN using home service provider (HSP) subscription of a HSP network is supported. The UE can be configured with subscription information of the HSP network. The subscription information can include the HSP subscription and a home SP selection list that includes one or more candidate networks each represented by an SNPN identifier. The method can further include responsive to the system information, selecting a network from the home SP selection list according to a priority order of the candidate networks, and accessing the network selected from the home SP selection list using the HSP subscription.

Abstract: A method of handling a Packet Data Network (PDN) connection to support interworking to 5G system (5GS) is proposed. In a first novel aspect, both UE and the network stores mapped 5GSM parameters of a corresponding Protocol Data Unit (PDU) session when inter-system change from S1 (4G, EPS) mode to A/Gb (2G) mode or Iu (3G, UMTS) mode. In a second novel aspect, the PDN connection is enable to support interworking to 5GS, and the UE is allowed to allocate and indicate the PDU session ID by using the bearer resource modification procedure in EPS, or the mapped 5GSM parameters can be provided and modified in 2G/3G system.

Abstract: A method can include receiving a “create new evolved packet system (EPS) bearer” operation code in a mapped EPS bearer contexts information element (IE) in a first protocol data unit (PDU) session modification command message for creating a mapped EPS bearer context at a user equipment (UE) in a wireless communication system, and when there is neither a quality of service (QoS) flow descriptions IE in the first PDU session modification command message indicating a QoS flow description corresponding to an EPS bearer identity (EBI) in the mapped EPS bearer context, nor an existing QoS flow description at the UE corresponding to the EBI included in the mapped EPS bearer context, sending a PDU session modification request message including a mapped EPS bearer contexts IE to delete the mapped EPS bearer context.

Abstract: A method of handling insufficient resources in a user equipment (UE) during a PDU session establishment procedure is proposed. During a PDU session establishment procedure, UE sends a PDU SESSION ESTABLISHMENT REQUEST message to the network. UE then receives a PDU SESSION ESTABLISHMENT ACCEPT message from the network, the ACCEPT message carries various PDU session parameters including authorized QoS rules and QoS flows. If UE decides to reject the addition of the new authorized QoS flow description or the new authorized QoS rule due to lack of resources, UE may initiate a PDU session release procedure with 5G session management (5GSM) cause IE #26 “insufficient resources”. In an alternative embodiment, UE may synchronize with the network by sending a PDU session modification request message to delete certain QoS rules/flow descriptions with 5GSM cause IE #26 “insufficient resources”.

Abstract: A method of handling multi-access (MA) Protocol data unit (PDU) session under inter-system change is proposed. An MA PDU session uses one 3GPP access network or one non-3GPP access network at a time, or simultaneously one 3GPP access network and one non-3GPP access network. The UE and network can support Access Traffic Steering Switching and Splitting (ATSSS) functionalities to distribute traffic over 3GPP access and non-3GPP access for the established MA PDU session. Upon intersystem change from 5GS to EPS over the 3GPP access, if interworking with EPS is not supported, the MA PDU session is maintained in 5GS over the non-3GPP access type. Data traffic over of the MA PDU session over the 3GPP access type is transferred to the non-3GPP access type.