Qualcomm Incorporated

Vitaly Drapkin

Shyamal Ramachandran

Abhishek Bhatnagar

Thomas Klingenbrunn

Osama Lotfallah

Zhong Ren

Kuo-Chun Lee

Raghu Narayan Challa

Lenaig Genevieve Chaponniere

Daniel Amerga

Lorenzo Casaccia

Bhupesh Manoharlal Umatt

Muralidharan Murugan

Dinesh Dharmaraju

Cogol Tina

Pradeep Sagane Gowda

Swaminathan Sureshchandran

Sudhir S Halbhavi

Srinivasan Balasubramanian

Arvind Vardarajan Santhanam

Haris Zisimopoulos

Adrian Edward Escott

Ajith Tom Payyappilly

Hariharan Sukumar

Vamsi Dokku

Dominique Francois Bressanelli

Cherng-Shung Hsu

Bhanu Kiran Janga

Ajit Gupta

Xuepan Guan

Swathi Seshadri

Vidula Rajeev Kurundkar

Rekha S Iyer

Kanuganti Rajeswar Reddy

Anisha Elizabeth Jonas

Vamsi Krishna Dokku

A method is provided. The method may be performed by a UE. The method includes attempting to attach to or to perform a tracking area update in an EPS network to obtain voice services for a number of times. The method includes starting a modified timer based on a failure to attach to or to perform the tracking area update in an EPS network for the number of times and based on a configuration parameter. The modified timer may be modified based on a default timer. The method includes keeping an S1 mode enabled when starting the modified timer. The method includes attempting to obtain the voice services based on one or more access technologies other than EPS. The method includes attaching to or performing a tracking area update in the EPS network to obtain voice services based on the modified timer.

IMS voice support in network using EPS fallback and having 4G coverage holes

Aspects disclosed herein facilitate security handling of 5GS to EPC reselection are disclosed herein. An example method at a UE includes transmitting a first TAU request, the first TAU request encoded using a first security context associated with a first RAT, the first TAU request being integrity protected using a first uplink count based on the first security context, and the first TAU request including a first set of information including an identifier mapped to a second RAT associated with the first network entity. The example method also includes transmitting a second TAU request, the second TAU request including the first set of information, the second TAU request being integrity protected using a second uplink count. The example method also includes communicating based on a mapped security context based on the first security context and at least one of the first uplink count or the second uplink count.

Security handling of 5GS to EPC reselection

Techniques and apparatus for optimizing an initial access stratum security mode command procedure are described. One example technique includes sending a first service request to establish a connection with a network. A second service request is sent to the network, upon determining that one or more criteria is satisfied. Another example technique includes sending a first service request to establish a connection with a network and sending a second service request after sending the first service request. The first service request is associated with a first security parameter and the second service request is associated with a second security parameter. A security mode command procedure is participated in with a base station, based on the first security parameter and the second security parameter.

Optimization for an initial access stratum security mode command procedure

Methods, systems, and devices for wireless communication are described for inter-RAT mobility from a first radio access technology (RAT) to a second RAT, including cases in which different RATs correspond to different generations of networks. Approaches described herein include providing a preemptive indication of inter-RAT mobility for one or more geographic areas such to a user equipment (UE). The UE can thus use a mobility procedure to transition from the first RAT to the second RAT that is supported in the UE's location without first attempting an unsupported mobility procedure, reducing transition latency.

Preemptive indication of inter-rat mobility

Methods and apparatus are provided for avoiding attempts by a UE to attach to a RAT network when that RAT network is unavailable. According to certain aspects, the UE may detect scenarios when the RAT network is unavailable and take preemptive action to prevent the UE from attempting to acquire service on that RAT. For example, the UE may effectively remove that RAT from a list of supported RATs by sending a UE capability message indicating that RAT is not supported, which may prevent network-initiated transitions of the UE to that RAT. The UE may also remove the unavailable RAT from an internal list of supported RATs, which may prevent UE-initiated transitions to that RAT.

Methods and systems for avoiding transitions between radio access technologies when packet data networks are inaccessible

Certain aspects of the present disclosure propose techniques for independently signaling features supported by a user equipment (UE) in different duplexing modes. The UE may be capable of communicating in frequency division duplexing (FDD) and time division duplexing (TDD) modes. The UE may obtain a FDD-specific feature group indicators (FGIs) set and a TDD-specific FGIs set, and signal at least one of the FDD-specific FGIs set or TDD-specific FGIs set. In addition, the UE may take one or more actions to reduce the likelihood of transitioning to a mode of operation that is different from its current mode of operation.

Methods and apparatus for employing different capabilities for different duplexing modes

Certain aspects of the present disclosure relate to methods and apparatus for improving data service availability. Certain aspects provide methods and apparatus for wireless communications by a UE including determining, while the UE is in a coverage area of a first network, that a connection to a second network, comprising a packet data network (PDN), is disconnected locally, and taking at least one action to avoid a rejection of a request to connect to the second network.

Methods and apparatus for improving data service availability

Techniques are described for power conservation in emergency broadcast message reception in a wireless communications system. In accordance with a method for conserving power, one or more segments of an emergency broadcast message in an access stratum are received. The emergency broadcast message is identified as a duplicate emergency broadcast message based at least in part on one or more identifiers of the received one or more segments. The receipt of additional segments of the emergency broadcast message is terminated.

Techniques for power conservation in emergency broadcast message reception

Methods, systems, apparatuses and devices are described for managing a call during radio link failure. In one embodiment, radio link failure over a radio access technology may be detected during or after a call setup procedure. A public land mobile network and an equivalent public land mobile network may be selected. An initial search for cells of the radio access technology may be performed over the selected public land mobile network and the equivalent public land mobile network. The initial search may be performed once or twice based on a configurable parameter.

Enhance performance of making an emergency call during radio link failure over radio access technology

Techniques for deriving message counts based at least in part on a locally stored message count and at least a portion of a message count received from a remote network node are disclosed. The message counts can relate to downlink (DL) non-access stratum (NAS) counts. In one aspect, a device can receive a number of least significant bits of the DL NAS count in a handover message. The device can derive a DL NAS count by utilizing a remaining portion of most significant bits of a locally stored DL NAS count, and can determine whether to increment or decrement the most significant bits based at least in part on a parameter to handle cases where the least significant bits of the locally stored DL NAS count have wrapped due to overflow and/or underflow.

Determining a non-access stratum message count in handover

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San Diego, CA, United States of America

Vitaly Drapkin