CROSS REFERENCE

The present application for patent claims the benefit of Greece Provisional Patent Application No. 20180100274 by ZHU, et al., entitled “PACKET SWITCHED VOICE CALL CAPABILITY INDICATION IN WIRELESS COMMUNICATIONS,” filed Jun. 21, 2018, assigned to the assignee hereof, and expressly incorporated herein.

BACKGROUND

The following relates generally to wireless communications, and more specifically to packet switched voice call capability indication in wireless communications.

Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple-access systems include fourth generation (4G) systems such as Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and fifth generation (5G) systems which may be referred to as New Radio (NR) systems. These systems may employ technologies such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal frequency division multiple access (OFDMA), or discrete Fourier transform-spread-OFDM (DFT-S-OFDM). A wireless multiple-access communications system may include a number of base stations or network access nodes, each simultaneously supporting communication for multiple communication devices, which may be otherwise known as user equipment (UE).

In some deployments, voice calls may be conducted using packet switching, such as voice over Internet protocol (VoIP), voice over LTE (VoLTE) for some LTE deployments, or voice over NR (VoNR) for some NR deployments. Packet switched voice calls may be generally referred to as voice over packet switching (VoPS). In other deployments, voice calls may be conducted with circuit switching (CS). Further, in some cases, a packet-based wireless communications system (e.g., an LTE or NR system), or one or more UEs operating within the system, may not have a capability of supporting VoPS, and fallback techniques may be implemented to establish the voice call using a different radio access technology. For example, a NR system or UE operating within the system may not support VoNR, and the UE may fallback to an LTE system, or a 3G or 2G system, when establishing a voice call. Efficient techniques for implementing such fallback techniques may be beneficial to help enhance network efficiency.

SUMMARY

The described techniques relate to improved methods, systems, devices, and apparatuses that support packet switched voice call capability indication in wireless communications. In various aspects, described techniques provide for a user equipment (UE) to report packet switched voice call capabilities to a base station. A UE may transmit a system-level parameter to the base station that indicates whether the UE has a capability to support packet switched voice calls. In some examples, the base station may operate in a first radio access network (RAN), such as a 5G or new radio (NR) RAN. In cases where the UE indicates a capability for packet switched voice calls via the first RAN, one or more voice calls may be established with the UE via the first RAN. In cases where the UE indicates that it is not capable of packet switched voice calls via the first RAN, the UE may fall back to a different RAN (e.g., a 4G or LTE RAN, a 3G RAN, or a 2G RAN) for voice calls.

In some cases, the UE may provide a number of capability bits indicating different capabilities of the UE. Such capability bits may include, for example, an indication of UE capability to support packet switched voice calls via frequency division duplexing (FDD) using the first RAN, an indication of UE capability to support packet switched voice calls via time division duplexing (TDD) using the first RAN, an indication of UE capability to support packet switched voice calls in a higher frequency range (e.g., via beamformed transmissions in a frequency range above 6 GHz (e.g., FR2)) using the first RAN, or combinations thereof. In some cases, the system parameters may include one or more indications of capabilities of the UE to support packet switched voice calls via a second RAN (e.g., a 4G or LTE RAN), such as an indication of UE capability for frequency division duplexing (FDD) for voice calls via the second RAN, time division duplexing (TDD) for voice calls via the second RAN, or combinations thereof. Additionally or alternatively, the system parameters may include an indication of UE capability for single radio voice call continuity (SRVCC) to hand over a voice call from a packet switched domain to a circuit switched domain.

In some cases, a UE may also initiate a connection establishment procedure with a second base station to establish a second wireless connection using a second RAN, and may transmit, as part of the second connection establishment, a second system-level parameter that indicates whether the UE has the capability to support packet switched voice calls via the first RAN. In some cases, base stations may receive a list of restricted tracking areas (TAs) or base stations that are restricted from receiving a handover of packet switched voice calls, which may prevent a UE with an established VoPS call from being handed over to a base station that does not support VoPS.

A method of wireless communication at a UE is described. The method may include initiating a connection establishment with a base station to establish a wireless connection using a first radio access network (RAN), transmitting, to the base station, a system-level parameter that indicates whether the UE has a capability to support packet switched voice calls via the first RAN and one or more capability bits for component features of packet switched voice calls, and communicating with the base station using the first RAN based on the system-level parameter.

An apparatus for wireless communication at a UE is described. The apparatus may include a processor, memory in electronic communication with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to initiate a connection establishment with a base station to establish a wireless connection using a first radio access network (RAN), transmit, to the base station, a system-level parameter that indicates whether the UE has a capability to support packet switched voice calls via the first RAN and one or more capability bits for component features of packet switched voice calls, and communicate with the base station using the first RAN based on the system-level parameter.

Another apparatus for wireless communication at a UE is described. The apparatus may include means for initiating a connection establishment with a base station to establish a wireless connection using a first radio access network (RAN), transmitting, to the base station, a system-level parameter that indicates whether the UE has a capability to support packet switched voice calls via the first RAN and one or more capability bits for component features of packet switched voice calls, and communicating with the base station using the first RAN based on the system-level parameter.

A non-transitory computer-readable medium storing code for wireless communication at a UE is described. The code may include instructions executable by a processor to initiate a connection establishment with a base station to establish a wireless connection using a first radio access network (RAN), transmit, to the base station, a system-level parameter that indicates whether the UE has a capability to support packet switched voice calls via the first RAN and one or more capability bits for component features of packet switched voice calls, and establish the connection with the base station using the first RAN based on the system-level parameter.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for establishing a voice call via the first RAN based on the system-level parameter indicating that the UE may be capable to support packet switched voice calls via the first RAN. Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving a handover or redirect command to a second RAN based on the system-level parameter indicating that the UE lacks the capability to support packet switched voice calls via the first RAN. In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first RAN may be a 5G or new radio (NR) RAN, and the second RAN may be a 4G, 3G, or 2G RAN.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the transmitting further may include operations, features, means, or instructions for transmitting a set of system parameters for capabilities of vertical features that involve two or more protocol layers. In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the system-level parameter may include a first capability bit that indicates UE capability to support packet switched voice calls via FDD using the first RAN, and where the transmitting further includes and transmitting a second capability bit that indicates UE capability to support packet switched voice calls via TDD using the first RAN, and a third capability bit that indicates UE capability to support packet switched voice calls via transmissions in a higher frequency range (e.g., FR2) using the first RAN.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the transmitting further may include operations, features, means, or instructions for transmitting an indication of a second capability of the UE to support packet switched voice calls via a second RAN. In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the indication of the second capability of the UE indicates UE capability for FDD for voice calls via the second RAN, TDD for voice calls via the second RAN, or combinations thereof. In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the indication of the second capability of the UE indicates UE capability for single radio voice call continuity (SRVCC) to hand over a voice call from a packet switched domain to a circuit switched domain.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for initiating a second connection establishment with a second base station to establish a second wireless connection using a second RAN and transmitting, to the second base station, a second system-level parameter that indicates whether the UE may have the capability to support packet switched voice calls via the first RAN.

A method of wireless communication is described. The method may include initiating, at a base station in a first radio access network (RAN), a connection establishment with a UE, receiving, from the UE, a system-level parameter that indicates whether the UE has a capability to support packet switched voice calls via the first RAN and one or more capability bits for component features of packet switched voice calls, and communicating with the UE based on the system-level parameter.

An apparatus for wireless communication is described. The apparatus may include a processor, memory in electronic communication with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to initiate, at a base station in a first radio access network (RAN), a connection establishment with a UE, receive, from the UE a system-level parameter that indicates whether the UE has a capability to support packet switched voice calls via the first RAN and one or more capability bits for component features of packet switched voice calls, and communicate with the UE based on the system-level parameter.

Another apparatus for wireless communication is described. The apparatus may include means for initiating, at a base station in a first radio access network (RAN), a connection establishment with a UE, receiving, from the UE, a system-level parameter that indicates whether the UE has a capability to support packet switched voice calls via the first RAN and one or more capability bits for component features of packet switched voice calls, and communicate with the UE based on the system-level parameter.

A non-transitory computer-readable medium storing code for wireless communication is described. The code may include instructions executable by a processor to initiate, at a base station in a first radio access network (RAN), a connection establishment with a UE, receive, from the UE, a system-level parameter that indicates whether the UE has a capability to support packet switched voice calls via the first RAN and one or more capability bits for component features of packet switched voice calls, and communicate with the UE based on the system-level parameter.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for establishing a voice call for the UE via the first RAN based on the system-level parameter indicating that the UE may be capable to support packet switched voice calls via the first RAN. In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the system-level parameter indicates that the UE lacks the capability to support packet switched voice calls via the first RAN, and the UE may be handed over or redirected to a second base station of a second RAN to establish the voice call. In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the first RAN may be a 5G or new radio (NR) RAN, and the second RAN may be a 4G, 3G, or 2G RAN.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the receiving further may include operations, features, means, or instructions for receiving a set of system parameters for capabilities of vertical features of the UE that involve two or more protocol layers. In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the system-level parameter may include a first capability bit that indicates UE capability to support packet switched voice calls via FDD using the first RAN, and where the receiving further may include operations, features, means, or instructions for receiving, from the UE, a second capability bit that indicates UE capability to support packet switched voice calls via TDD using the first RAN, and a third capability bit that indicates UE capability to support packet switched voice calls via transmissions in a higher frequency range (e.g., FR2) using the first RAN.

In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the receiving further may include operations, features, means, or instructions for receiving an indication of a second capability of the UE to support packet switched voice calls via a second RAN. In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the indication of the second capability of the UE indicates UE capability for FDD for voice calls via the second RAN, TDD for voice calls via the second RAN, or combinations thereof.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for initiating a handover of the UE to a second base station of the second RAN based on the indication of the second capability of the UE. In some examples of the method, apparatuses, and non-transitory computer-readable medium described herein, the indication of the second capability of the UE indicates UE capability for single radio voice call continuity (SRVCC) to hand over a voice call from a packet switched domain to a circuit switched domain.

Some examples of the method, apparatuses, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for receiving a list of other base stations that may be restricted from establishing packet switched voice calls and initiating a handover of the UE to a second base station for a voice call based on the list of other base stations that may be restricted from establishing packet switched voice calls.

