Qualcomm Incorporated

Interdigital Patent Holdings, Inc.

Vid Scale, Inc.

Osama Lotfallah

Hang Liu

Xavier De Foy

Lenaig Genevieve Chaponniere

Kamel M Shaheen

Carlos Marcelo Dias Pazos

Arvind Vardarajan Santhanam

Debashish Purkayastha

Nagaraju Naik

Reza Shahidi

Amer Catovic

Kuo-Chun Lee

Shamim Akbar Rahman

Thomas Stockhammer

Liangchi Hsu

Yuriy Reznik

Ralph Akram Gholmieh

Charles Nung Lo

Bhupesh Manoharlal Umatt

Stephen William Edge

Masato Kitazoe

Qingxin Chen

Cheol Hee Park

Yousif Targali

Vikram Singh

Sony Akkarakaran

Gavin Bernard Horn

Tom Chin

Stefano M Faccin

Xipeng Zhu

Haris Zisimopoulos

Bharat Shrestha

Shailesh Maheshwari

Min Wang

Ajith Tom Payyappilly

Daniel Amerga

Jun Hu

Thadi Manjunath Nagaraj

Francesco Pica

Robert G Gazda

Milan Patel

Abhishek Bhatnagar

Qin Xue Frantti

Serhad Doken

Flora Pui San Chan

Eduardo Asbun

Vitaly Drapkin

Cherng-Shung Hsu

Xinning Shen

Subashini Krishnamurthy

Uttam Pattanayak

Cogol Tina

Zhong Ren

Rishav Rej

Adam Hebein

Manisha Priyadarshini

Brian A'hearn

Alan Soloway

Dominique Francois Bressanelli

Krishna Chaitanya Mukkera

Mona Agrawal

Yong Xie

Hemanth Kumar Rayapati

Bhanu Kiran Janga

Nermeen Ahmed Bassiouny

Hamza Ijaz Abbasi

Xuepan Guan

Sandeep Ramannavar

Elmira Mazloomian

Xinli Song

Swathi Seshadri

Xavier Defoy

Sohrab Ahmad

Zhiyuan Lu

Quanling Zhang

Nagaraja Shivashankar

Shamim A Rahman

Methods, systems, and devices for wireless communications are described. Generally, the described techniques provide for efficiently falling back from one RAT to another RAT while maximizing the services available to a UE. When a request from a UE for communicating with a base station using one RAT is rejected by a network node for unexpected causes, the UE may use the techniques described herein to fallback to an appropriate RAT. For instance, after receiving a response indicating that a request including fifth generation (5G) parameters is rejected, the UE may drop the 5G parameters and fall back to fourth generation (4G), rather than falling back to second generation (2G) or third generation (3G). The unexpected causes may be preconfigured and may be determined based on a number of factors, including a subscription of the UE, a public land mobile network (PLMN) associated with the network node, etc.

Radio access technology switching based on network support

A method of wireless communication performs a public land mobile network (PLMN) search for a higher priority PLMN. The PLMN search includes a candidate PLMN having a different mobile country code (MCC) than a serving PLMN. The method switches to the higher priority PLMN when the PLMN search locates the higher priority PLMN. A method determines whether a user equipment (UE) has transitioned between an international area and a national area. The method triggers PLMN selection in response to the UE having transitioned between the international area and the national area.

Wireless network selection in international areas

Aspects of the present disclosure relate to wireless communications, and more particularly, to techniques for optimizing procedures to update a UE radio capability ID (URCID) when a UE moves to a new Public Land Mobile Network (PLMN) within a registration area. The techniques may help avoid unnecessary signaling traffic and reduce UE power consumption. An example method performed by a user equipment (UE) generally includes receiving at least one URCID assigned by a first PLMN; and taking one or more actions to delay or avoid updating the URCID when moving to a second PLMN in a same registration area as the first PLMN.

Delaying UE radio capability ID (URCID) update for EPLMN

A UE in cellular communication system may be equipped with multiple User Services Identity Modules (USIMs) to support multiple service subscriptions. The UE having multiple service subscriptions may obtain services from one or more wireless networks with each of the subscriptions. When the UE having multiple service subscriptions needs to make an emergency call, the UE may identify and determine a service subscription to make the emergency call, so that the emergency call can be successfully made. The UE may be implemented with a communication processor (modem) and an application processor (AP). Some information that is useful to identify a service subscription more suitable for the emergency call may be available only at the communication processor. Enhanced techniques for identifying and determining a service subscription to make the emergency call from the multiple service subscriptions through interaction between the communication processor and the application processor are disclosed.

Techniques for managing subscription identification for emergency call

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive, from a network, a procedure rejection message for non-cellular access at a non-access stratum (NAS) layer, and provide a first congestion indication from the NAS layer to lower layers for non-cellular access based at least in part on the receiving the procedure rejection message. The UE may refrain, at the lower layers, from initiating establishment of a signaling connection based at least in part on the first congestion indication. Numerous other aspects are provided.

Non-access stratum congestion indications

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

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may establish, using a first subscription of the UE, a first communication connection associated with a first service. The UE may establish, using a second subscription of the UE, a second communication connection associated with a second service. The UE may operate in a dual subscriber identity module (SIM) dual active (DSDA) mode based at least in part on establishing the first communication connection and establishing the second communication connection. The UE may perform an action to maintain concurrent services, including the first service and the second service, while operating in the DSDA mode. Numerous other aspects are described.

Maintaining concurrent services in a dual active mode

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may detect that a first subscription, of a plurality of subscriptions associated with the UE, is associated with an active service on a first cellular network. The UE may search, for a second subscription of the plurality of subscriptions, for radio access technologies (RATs) and frequency bands that are compatible with a dual active mode of the UE. In some aspects, the UE may detect that the active service on the first cellular network has ended. Accordingly, the UE may search, for the second subscription, for RATs and frequency bands that are compatible with the dual active mode of the UE and for RATs and frequency bands that are incompatible with the dual active mode, before expiry of a timer associated with a power saving state. Numerous other aspects are described.

Radio access technology searching in dual active mode

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

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may detect, while operating in an out-of-service (OOS) mode associated with a first network, that a second network satisfies one or more switching criteria. The UE may increase a time duration associated with a periodic network acquisition scan associated with the first network based at least in part on detecting that the second network satisfies the one or more switching criteria. The UE may switch, while operating in the OOS mode, from using the first network for connectivity to using the second network for connectivity based at least in part on detecting that the second network satisfies the one or more switching criteria. Numerous other aspects are described.

Efficient network acquisition scans

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

The present disclosure relates to a user equipment (UE) dynamically adjusting a non-access stratum (NAS) timer. Specifically, the UE may determine operation in a wideband and support of an extended coverage (EC) restriction. The UE may further identify a duration of a non-access stratum (NAS) timer based on determining operation in the wideband and the EC restriction. The UE may further transmit an access request message to a network entity to trigger a mobility management procedure. The UE may further receive an acceptance message from the network entity indicating an unrestricted or restricted status of the EC restriction. The UE may further apply the duration to the NAS timer based on the acceptance message indicating the unrestricted or restricted status of the EC restriction received from the network entity or a history of EC restrictions of a public land mobile network (PLMN) in a defined geographic area.

Techniques for user equipment (UE) dynamically adjusting a non-access stratum (NAS) timer in a wireless communication system

Some aspects described herein relate to determining to fallback from a first radio access technology (RAT) to a second RAT to perform an emergency call, and deprioritizing, based on the determining to fallback, access to the first RAT to continue to use the second RAT for at least a period of time after the emergency call.

Techniques for radio access technology (RAT) fallback in wireless communications

Growing community of inventors

San Diego, CA, United States of America

Osama Lotfallah