Abstract: Systems and methods provide steering of roaming (SoR) information during a user equipment (UE) mobility registration process. In other systems and methods, instead of triggering mobility and periodic registration, a UE performs initial registration until a valid SoR is received in a visited country or network as long as a subscriber identification module (SIM) or a universal SIM (USIM) of the UE indicates that the UE is expected to receive SoR information due to initial registration in a visited public land mobile network (VPLMN).

Abstract: Methods and apparatuses are disclosed for requesting and providing service of a network slice deemed essential by a user equipment (UE). The UE transmits a request message to the network indicating that essential services are requested, and identifying the essential network slice. Based on the information in the request message, the serving network communicates with one or more network nodes to determine whether the requested services can be provided. This information is packaged in a response message and transmitted to the UE. If the current network is capable of servicing the requested network slice, then the UE remains with the current network. If not, then the UE initiates a search for an alternative network (PLMN or SNPN) capable of supporting the requested services. A successful search causes the UE to register with the newly-found network, whereas an unsuccessful search causes the UE to re-register with the current network.

Abstract: Apparatuses and computer-readable storage media for handling timers for mobile terminated circuit-switched fallback (MT CSFB) calls. An apparatus for a user equipment (UE) includes processing circuitry operably coupled to a data storage device. The data storage device is configured to store a value of an extended service request for mobile terminated services (EXT-MT) timer. The value of the EXT-MT timer is less than a value of a guard timer of a Visitor Location Register (VLR). The processing circuitry is configured to start the EXT-MT timer and generate an extended service request message to be transmitted to a Mobility Management Entity (MME) responsive to a paging for an MT CSFB call, and attempt to select a radio access technology of a different type of network if the EXT-MT timer expires before the UE successfully performs inter system change and a circuit switched fallback cancellation request was not received from a subscriber.

Abstract: This disclosure relates to a user equipment (UE) circuitry comprising a processor, wherein the processor is configured to: receive a message indicating a redirection from a first radio network to a second radio network while the UE is registered in the first radio network under a first location area code (LAC); initiate a cell search for radio cells of the second radio network, wherein a specific LAC is assigned to at least one radio cell of the second radio network; and connect to a first radio cell found by the cell search based on a comparison of a LAC of the first radio cell and the first LAC under which the UE is registered in the first radio network.

Abstract: This disclosure relates to a mobile device, comprising: a receiver configured to receive a radio signal comprising transmissions from a plurality of radio cells; and a processor configured to derive second information from the received radio signal, the second information indicating at least one neighboring radio cell, wherein the processor is configured to initiate a radio cell selection based on the second information if the second information indicates at least one neighboring radio cell configured for the first RAT.

Abstract: Systems and methods of enabling access for non-emergency voice calls are described. A UE operates in a network supporting voice services via a multitude of RATs. The UE attempts to access the network via a first RAT offering voice services and data services. If the UE does not receive a response from the network within a first time period, the UE re-attempts the access to the network via the first RAT. If the number of access attempts for which the UE does not receive a response is at least a threshold value, the UE refrains during a second time period from further access attempts via the first RAT for the purpose of receiving data services, and continues to attempt access via the first or second RAT for the purpose of receiving voice services.

Abstract: Embodiments of a User Equipment (UE) and methods for communication in multi-mode environments are generally described herein. The UE may operate in a failure state as part of a packet-switched (PS) communication session with a PS network, such as a 3GPP LTE network. The UE may determine that a circuit-switched (CS) communication session with a CS network is to be established. The UE may transmit, while operating in the failure state of the PS communication session, a CS registration message to a CS base station of the CS network as part of an establishment of the CS communication session. The UE may refrain from transmission, while operating in the failure state, of messages to the PS network for the establishment of the CS communication session.

Abstract: This disclosure relates to a mobile device, comprising: a receiver configured to receive a radio signal comprising transmissions from a plurality of radio cells; and a processor configured to derive second information from the received radio signal, the second information indicating at least one neighboring radio cell, wherein the processor is configured to initiate a radio cell selection based on the second information if the second information indicates at least one neighboring radio cell configured for the first RAT.

Abstract: Apparatuses and computer-readable storage media for handling timers for mobile terminated circuit-switched fallback (MT CSFB) calls. An apparatus for a user equipment (UE) includes processing circuitry operably coupled to a data storage device. The data storage device is configured to store a value of an extended service request for mobile terminated services (EXT-MT) timer. The value of the EXT-MT timer is less than a value of a guard timer of a Visitor Location Register (VLR). The processing circuitry is configured to start the EXT-MT timer and generate an extended service request message to be transmitted to a Mobility Management Entity (MME) responsive to a paging for an MT CSFB call, and attempt to select a radio access technology of a different type of network if the EXT-MT timer expires before the UE successfully performs inter system change and a circuit switched fallback cancellation request was not received from a subscriber.

Abstract: This disclosure relates to a mobile device, comprising: a receiver configured to receive a radio signal comprising transmissions from a plurality of radio cells; and a processor configured to derive second information from the received radio signal, the second information indicating at least one neighboring radio cell, wherein the processor is configured to initiate a radio cell selection based on the second information if the second information indicates at least one neighboring radio cell configured for the first RAT.

Abstract: Delay in IMS call establishment and other time critical data transfers may be reduced by seeking alternative transmission methods for time critical data, when a transmission cannot be completed or the Radio Access Technology is otherwise unavailable. A Critical Service Manager (“CSM”) receives and evaluates priority information about a given data transfer. By evaluating this priority information, the CSM can identify priority data, or latency intolerant data, such as IMS calls or emergency calls. Where network rejects a connection request and issues a wait timer, the CSM may lower the retransmission count to hasten a permanent transmission failure. Upon a permanent transmission failure, the CSM can determine an alternative protocol for transmission of the priority data, such as transmitting data through circuit switch fallback, via Wi-Fi, or through another legacy RAT.

Abstract: This disclosure relates to a mobile device, comprising: a receiver configured to receive a radio signal comprising transmissions from a plurality of radio cells; and a processor configured to derive second information from the received radio signal, the second information indicating at least one neighboring radio cell, wherein the processor is configured to initiate a radio cell selection based on the second information if the second information indicates at least one neighboring radio cell configured for the first RAT.

Abstract: Techniques described herein may enable a wireless cellular network to transfer a call from a packet-switched (PS) portion of the wireless cellular network to a circuit-switched (CS) portion of the wireless cellular network, in a manner that ensures that the CS network receiving the call can actually support the call. For instance, before the wireless cellular network selects RAT for the CS network for transferring a call, the wireless cellular network may identify a call type for the call (e.g., simple voice call, video call, etc.), identify a RAT for the CS network that can support the call type, and proceed to transfer the call to the CS portion of the wireless cellular network that can support the call type, thus ensuring that the call is not dropped as a result of the transfer.

Abstract: Embodiments of a User Equipment (UE) and methods for communication in multi-mode environments are generally described herein. The UE may operate in a failure state as part of a packet-switched (PS) communication session with a PS network, such as a 3GPP LTE network. The UE may determine that a circuit-switched (CS) communication session with a CS network is to be established. The UE may transmit, while operating in the failure state of the PS communication session, a CS registration message to a CS base station of the CS network as part of an establishment of the CS communication session. The UE may refrain from transmission, while operating in the failure state, of messages to the PS network for the establishment of the CS communication session.

Abstract: Delay in IMS call establishment and other time critical data transfers may be reduced by seeking alternative transmission methods for time critical data, when a transmission cannot be completed or the Radio Access Technology is otherwise unavailable. A Critical Service Manager (“CSM”) receives and evaluates priority information about a given data transfer. By evaluating this priority information, the CSM can identify priority data, or latency intolerant data, such as IMS calls or emergency calls. Where network rejects a connection request and issues a wait timer, the CSM may lower the retransmission count to hasten a permanent transmission failure. Upon a permanent transmission failure, the CSM can determine an alternative protocol for transmission of the priority data, such as transmitting data through circuit switch fallback, via Wi-Fi, or through another legacy RAT.

Abstract: A communication terminal is described comprising a communication circuit configured to establish a first radio link to a first communication network; and to receive, via the first radio link to the first communication network, a message from the first communication network that indicates establishing a second radio link to a second communication network for a call; a controller configured to select at least one channel frequency from a plurality of stored channel frequencies provided for the call to the second communication network; control the communication circuit to establish the second radio link to the second communication network using the selected at least one channel frequency and to establish the call via the established second radio link.

Abstract: A communication device and a method to perform a switch from a first radio access technology (RAT) to a second RAT consisting of detecting multiple pending transactions to be conducted on the second RAT, switching from the first RAT to the second RAT, conducting the multiple pending transactions on the second RAT, and implementing a restriction on switching back to the first RAT for at least the duration while the multiple transactions on the second RAT is taking place.

Abstract: A device and a method to search a public landline mobile network for a radio access technology network, consisting of scanning a frequency band, wherein the signal strengths for the frequencies in the frequency band are measured, and performing an analysis of the signal strengths for various sets of frequencies within the frequency band in order to differentiate between different radio access technology networks based on the uniformity of the signal strengths of the frequencies in their respective operating bandwidths within the frequency band.

Abstract: An improved circuit switched fallback (CSFB) method is disclosed, in which failures following several abnormal cases not anticipated by the 3rd Generation Partnership Project (3GPP) specification are avoided. User equipment implementing the improved CSFB method demonstrate increased performance in terms of call success rate and hence provide an improved user experience and an edge over Long Term Evolution (LTE) modem competitors. The improved CSFB method can be included in the 3GPP standards for such abnormal case handling and CSFB call recovery.

Abstract: A communication device and a method to perform a switch from a first radio access technology (RAT) to a second RAT consisting of detecting multiple pending transactions to be conducted on the second RAT, switching from the first RAT to the second RAT, conducting the multiple pending transactions on the second RAT, and implementing a restriction on switching back to the first RAT for at least the duration while the multiple transactions on the second RAT is taking place.