Techniques for voice call pause detection and mitigation

Abstract

Methods, systems, and devices for wireless communication are described for identifying voice call pauses for packet switched voice calls. A user equipment (UE) may establish a packet-based voice call with a peer device via a wireless communication system. The packet-based voice call may be evaluated by the UE to determine the presence of a voice call pause, and a handover of the UE to a different serving cell or a different radio access technology may be triggered in the event that a voice call pause is detected. The voice call pause may be identified based on a threshold of the number of voice call packets expected to be received during the evaluation period. Handover of the UE may be initiated if the number of voice call packets received during the evaluation period is below the threshold.

Description

Technical Field

[0001] The following relates to wireless communications, including techniques for voice call hang detection and mitigation. Background Art

[0002] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, broadcast, and the like. These systems may be able to support communication with multiple users by sharing 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, advanced LTE (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 techniques such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM). A wireless multiple access communication system may include one or more base stations, each of which supports wireless communications for communication devices, which may be referred to as user equipment (UE).

[0003] In some cases, voice calls of wireless communication systems may be carried using packet-based technologies, such as Voice over Internet Protocol (VoIP) or Voice over IP Multimedia Subsystem (VoIMS). Such packet-based technologies provide for peer devices (e.g., two UEs in a voice call, or a UE and a different packet-based voice call device) to exchange voice call packets that include voice data for the respective users. In some cases, the voice call may be stalled, which may cause the user of the peer device to have a gap in communication or a call failure and termination. Techniques for reducing communication gaps or call failures can help enhance the user experience by providing more reliable and higher quality packet-based voice calls. Summary of the invention

[0004] The described technology relates to improved methods, systems, devices and apparatuses that support technology for voice call pause detection and mitigation. For example, the described technology provides that a peer device (e.g., a user equipment (UE)) establishes a packet-based voice call with another peer device (e.g., a different UE or other packet-based voice call device) via a wireless communication system. The packet-based voice call can be evaluated at one or more times to determine the presence of a voice call pause. In the case of a voice call pause being detected, one or more mitigation actions can be taken, such as triggering a handover to a different serving cell at the physical layer of the UE, which can help avoid the termination of the call and help enhance the user experience. In some cases, a voice call pause can be identified based on a threshold of a voice pause, wherein the threshold is based on the number of voice call packets expected to be received during an active call state of a packet-based voice call during an evaluation period. In the case where the number of voice call packets received during the evaluation period is lower than a threshold, a handover from a first serving cell to a different serving cell can be initiated.

[0005] A method for wireless communication at a UE is described. The method may include establishing a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system; identifying a threshold for voice pauses for the packet-based voice call, the threshold being based on a number of voice call packets expected to be received during an active call state of the packet-based voice call during an evaluation period; and in response to a number of voice call packets received from the peer device during the evaluation period being below the threshold for voice pauses for the packet-based voice call, initiating a handover of the UE from the first wireless network entity to a different wireless network entity.

[0006] An apparatus for wireless communication at a UE is described. The apparatus may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions may be executed by the processor to cause the apparatus to establish a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system; identify a threshold for voice pauses for the packet-based voice call, the threshold being based on the number of voice call packets expected to be received during an active call state of the packet-based voice call during an evaluation period; and in response to the number of voice call packets received from the peer device during the evaluation period being lower than the threshold for voice pauses for the packet-based voice call, initiate a handover of the UE from the first wireless network entity to a different wireless network entity.

[0007] Another apparatus for wireless communication at a UE is described. The apparatus may include means for establishing a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system; means for identifying a threshold for voice pauses for the packet-based voice call, the threshold being based on a number of voice call packets expected to be received during an active call state of the packet-based voice call during an evaluation period; and means for initiating a handover of the UE from the first wireless network entity to a different wireless network entity in response to a number of voice call packets received from the peer device during the evaluation period being below the threshold for voice pauses for the packet-based voice call.

[0008] 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: establish a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system; identify a threshold for voice pauses for the packet-based voice call, the threshold being based on a number of voice call packets expected to be received during an active call state of the packet-based voice call during an evaluation period; and in response to a number of voice call packets received from the peer device during the evaluation period being below the threshold for voice pauses for the packet-based voice call, initiate a handover of the UE from the first wireless network entity to a different wireless network entity.

[0009] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for receiving, from a peer device, an indication of a number of packets for a packet-based voice call sent from the peer device, and wherein initiating a handover of the UE may be based on a ratio of the number of voice call packets received from the peer device to the number of packets sent from the peer device during an evaluation period. In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the indication of the number of packets sent from the peer device may be received in a Real-time Transport Control Protocol (RTCP) transmitter report from the peer device.

[0010] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for determining that a time elapsed since a report associated with a packet-based voice call was received exceeds a time threshold, and wherein initiating a handover of the UE may be based on a number of voice call packets received from a peer device and an estimated number of voice call packets associated with an assumed mixed voice mode for an evaluation period. In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the report associated with the packet-based voice call may be an RTCP report.

[0011] In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the threshold may be based on a silence indicator (SID) interval of the packet-based voice call, wherein a higher SID interval may have a lower threshold and a lower SID interval may have a higher threshold. Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for the following actions: estimating the ratio of the expected number of packets sent from the peer device during the evaluation period to the maximum number of packets that can be sent during the evaluation period for the evaluation period, and wherein the threshold is determined based on the estimated ratio. In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, a value of the ratio less than the silence threshold indicates that the peer device is silent and the UE will suppress triggering a handover during the evaluation period. In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, the number of voice call packets received from the peer device during the evaluation period is based on voice call packets with a real-time transport protocol (RTP) timestamp within the evaluation period.

[0012] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, a threshold for identifying voice pauses and initiating a handover of a UE may be performed as part of a voice call pause evaluation, and wherein the method may include operations, features, components, or instructions for receiving at least one RTCP transmitter report indicating a number of RTP voice packets sent during an evaluation period and initiating a voice call pause evaluation in response to the at least one RTCP transmitter report, wherein the threshold is based on the number of RTP voice packets indicated in the transmitter report and the number of SID frames within the evaluation period.

[0013] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, a threshold for identifying a voice pause and initiating a handover of the UE may be performed as part of a voice call pause evaluation, and wherein the method may include operations, features, components, or instructions for determining that a certain period of time has passed since a previous evaluation period and no RTCP transmitter reports have been received during the period of time, and initiating a voice call pause evaluation in response to the determination, wherein the threshold is based on an assumed mixed voice pattern for the packet-based voice call. In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the threshold for identifying a voice pause for a packet-based voice call may be an adaptive threshold based on the amount of voice activity present during the evaluation period.

[0014] Some examples of the methods, apparatuses, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for the following actions: receiving a handover message indicating a handover of a UE from a first wireless network entity to a second wireless network entity, wherein the second wireless network entity uses the same radio access technology (RAT) as the first wireless network entity or a different RAT than the first wireless network entity. In some examples of the methods, apparatuses, and non-transitory computer-readable media described herein, initiating a handover of the UE may include operations, features, components, or instructions for the following actions: modifying criteria for sending a measurement report to the first wireless network entity that triggers the handover of the UE, wherein the measurement report may be an inter-RAT measurement report or an intra-RAT measurement report based on measured channel conditions associated with wireless network entities of two or more RATs. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 An example of a wireless communication system supporting techniques for voice call stall detection and mitigation in accordance with one or more aspects of the present disclosure is illustrated.

[0016] Figure 2 An example of a wireless communication system supporting techniques for voice call stall detection and mitigation in accordance with one or more aspects of the present disclosure is illustrated.

[0017] Figure 3 An example of a flow chart for voice call stall detection and mitigation in accordance with one or more aspects of the present disclosure is illustrated.

[0018] 4A to 4D An example of a timing diagram supporting techniques for voice call stall detection and mitigation in accordance with one or more aspects of the present disclosure is illustrated.

[0019] Figure 5 An example of a process flow supporting techniques for voice call stall detection and mitigation in accordance with one or more aspects of the present disclosure is illustrated.

[0020] Figure 6 and Figure 7 A block diagram of a device supporting techniques for voice call stall detection and mitigation in accordance with one or more aspects of the present disclosure is shown.

[0021] Figure 8 A block diagram of a communications manager supporting techniques for voice call stall detection and mitigation in accordance with one or more aspects of the present disclosure is shown.

[0022] Fig. 9 A diagram of a system including a device supporting techniques for voice call stall detection and mitigation is shown in accordance with one or more aspects of the present disclosure.

[0023] Figures 10 to 15 A flow chart illustrating a method of supporting techniques for voice call stall detection and mitigation in accordance with one or more aspects of the present disclosure is shown. DETAILED DESCRIPTION

[0024] In some cases, voice calls for wireless communication systems may be carried using packet-based technologies, such as Voice over IP Multimedia Subsystem (VoIMS) technologies (e.g., Voice over LTE (VoLTE), Voice over NR (VoNR)). Such packet-based technologies provide that a user equipment (UE), which may be an example of a peer device, may exchange voice call packets with another peer device, wherein the voice call packets include voice data for the respective users. In some cases, the voice call may be stalled, which may result in gaps in communications or call failures and terminations for the users of the peer devices. Techniques for reducing communication gaps or call failures may help enhance the user experience by providing more reliable and higher quality packet-based voice calls.

[0025] Voice pauses may occur during an active VoIMS (e.g., VoLTE or VoNR) call for any of a number of different reasons (e.g., poor channel quality of the wireless connection, network congestion, etc.), and regardless of the reason, the user may experience a gap in the communication that may result in a poor user experience. Various techniques discussed herein provide that voice pauses may be detected at the UE, and in some cases, the UE may detect voice pauses for downlink transmissions to the UE before user perception deteriorates, and the UE may proactively move to another serving cell or to a different radio access technology (RAT). Such techniques may help improve user experience and enhance network efficiency.

[0026] In some cases, a real-time transport protocol (RTP) application may be run at the application layer of the UE, and a packet-based voice call (e.g., a VoIMS call) may be managed according to a read time transmission control protocol (RTCP). In some conventional UEs, the RTP application at the UE may terminate the call after a certain period of time (e.g., 20 seconds), during which no voice packets are received at the RTP application. In such cases, the RTP application simply terminates the voice call, and does not provide any information or take any action to mitigate call interruption before terminating the call. Such techniques may result in a poor user experience because the call is not terminated for a relatively long duration (e.g., 20s), and the user must wait for the relatively long duration for termination or must terminate the call by itself before the duration expires. In addition, in some cases, the voice call may have intermittent pauses that have a shorter duration than the time period that causes the call termination at the RTP application (e.g., the voice call may pause for multiple four or five seconds), but result in a poor user experience.

[0027] According to the techniques discussed herein, a UE may establish a packet-based voice call with a peer device (e.g., a different UE or other packet-based voice call device) via a wireless communication system. The packet-based voice call may be evaluated by the UE at one or more occasions to determine the presence of a voice call pause. In the event that a voice call pause is detected, one or more mitigation actions may be taken, such as triggering a handover to a different serving cell at the physical layer of the UE, which may help avoid termination of the call and help enhance the user experience. In some cases, a voice call pause may be identified based on a threshold for a voice pause, wherein the threshold is based on the number of voice call packets expected to be received during an active call state of a packet-based voice call during an evaluation period. In the event that the number of voice call packets received during the evaluation period is below a threshold, a handover from a first serving cell to a different serving cell may be initiated.

[0028] In some cases, the RTP application at the UE may monitor voice packets received from a peer device and compare the number of received packets to a threshold to determine whether the voice call has been suspended. In some cases, the threshold may be an adaptive value based on the number of voice packets indicated in the RTCP transmitter report, a silence indicator (SID) interval (e.g., a SID frame is sent at the SID interval to indicate that there is no voice to be sent from the peer device), a default mixed voice mode (e.g., 40% talking, 40% listening, 20% silence), or a combination thereof. The threshold may be determined for each evaluation period based on the estimated voice activity, and if the number of voice packets received during the evaluation period is less than the threshold (e.g., if less than 20% of the expected voice packets are received), the UE may enter a voice suspension mode. In the event that the voice call has been suspended, the RTP application at the application layer may trigger the lower layers at the UE (e.g., the RRC / MAC layer) to initiate a handover of the UE to a different serving cell or a different RAT. In some cases, the lower layers may force the sending of measurement reports to initiate handover, such as by making a one-time adjustment to the Reference Signal Received Power (RSRP) increment of the neighboring cells to trigger the sending of measurement reports to initiate handover.

[0029] Various aspects of the present disclosure are first described in the context of a wireless communication system. Various aspects of the present disclosure are also illustrated by and described with reference to timing diagrams, process flows, device diagrams, system diagrams, and flow diagrams related to techniques for voice call stall detection and mitigation.

[0030] Figure 1 An example of a wireless communication system 100 supporting techniques for voice call stall detection and mitigation according to one or more aspects of the present disclosure is illustrated. The wireless communication system 100 may include one or more network entities 105, one or more UEs 115, and a core network 130. In some examples, the wireless communication system 100 may be a Long Term Evolution (LTE) network, an Advanced LTE (LTE-A) network, an LTE-A Pro network, a New Radio (NR) network, or a network operating according to other systems and radio technologies, including future systems and radio technologies not explicitly mentioned herein.

[0031] The network entities 105 may be dispersed throughout a geographic area to form the wireless communication system 100, and may include devices in different forms or with different capabilities. In various examples, the network entities 105 may be referred to as network elements, mobility elements, radio access network (RAN) nodes, or network equipment, among other nomenclature. In some examples, the network entities 105 and the UE 115 may communicate wirelessly via one or more communication links 125 (e.g., radio frequency (RF) access links). For example, the network entity 105 may support a coverage area 110 (e.g., a geographic coverage area) within which the UE 115 and the network entity 105 may establish one or more communication links 125. The coverage area 110 may be an example of a geographic area within which the network entity 105 and the UE 115 may support signal communications according to one or more radio access technologies (RATs).

[0032] The UEs 115 may be dispersed throughout the coverage area 110 of the wireless communication system 100, and each UE 115 may be stationary or mobile, or stationary and mobile at different times. The UEs 115 may be devices in different forms or with different capabilities. Figure 1 Some example UEs 115 are illustrated in FIG. 1. The UEs 115 described herein may be capable of supporting communications with various types of devices, such as Figure 1 Other UEs 115 or network entities 105 are shown.

[0033] As described herein, a node of the wireless communication system 100 (which may be referred to as a network node or a wireless node) may be a network entity 105 (e.g., any network entity described herein), a UE 115 (e.g., any UE described herein), a network controller, an apparatus, a device, a computing system, one or more components, or another suitable processing entity configured to perform any of the techniques described herein. For example, the node may be a UE 115. As another example, the node may be a network entity 105. As another example, a first node may be configured to communicate with a second node or a third node. In one aspect of this example, the first node may be a UE 115, the second node may be a network entity 105, and the third node may be a UE 115. In another aspect of this example, the first node may be a UE 115, the second node may be a network entity 105, and the third node may be a network entity 105. In other aspects of this example, the first node, the second node, and the third node may be different relative to these examples. Similarly, references to UE 115, network entity 105, apparatus, device, computing system, etc. may include disclosure of UE 115, network entity 105, apparatus, device, computing system, etc. as nodes. For example, a disclosure that UE 115 is configured to receive information from network entity 105 also discloses that the first node is configured to receive information from a second node.

[0034] In some examples, the network entities 105 may communicate with the core network 130, or communicate with each other, or both. For example, the network entities 105 may communicate with the core network 130 via one or more backhaul communication links 120 (e.g., according to S1, N2, N3 or other interface protocols). In some examples, the network entities 105 may communicate with each other via the backhaul communication link 120 (e.g., according to X2, Xn or other interface protocols) directly (e.g., directly between the network entities 105) or indirectly (e.g., via the core network 130). In some examples, the network entities 105 may communicate with each other via the midhaul communication link 162 (e.g., according to the midhaul interface protocol) or the fronthaul communication link 168 (e.g., according to the fronthaul interface protocol) or any combination thereof. The backhaul communication link 120, the midhaul communication link 162, or the fronthaul communication link 168 may be or include one or more wired links (e.g., electrical links, optical fiber links), one or more wireless links (e.g., radio links, wireless optical links), etc. or various combinations thereof. UE 115 may communicate with core network 130 via communication link 155 .

[0035] One or more of the network entities 105 described herein may include or may be referred to as a base station 140 (e.g., a transceiver base station, a radio base station, an NR base station, an access point, a radio transceiver, a Node B, an evolved Node B (eNB), a next-generation Node B, or a Gigabit Node B (any of which may be referred to as a gNB), a 5G NB, a next-generation eNB (ng-eNB), a Home Node B, a Home Evolved Node B, or other suitable terms). In some examples, the network entity 105 (e.g., a base station 140) may be implemented in an aggregated (e.g., monolithic, stand-alone) base station architecture, which may be configured to utilize a protocol stack physically or logically integrated within a single network entity 105 (e.g., a single RAN node, such as a base station 140).

[0036] In some examples, the network entity 105 may be implemented in a disaggregated architecture (e.g., a disaggregated base station architecture, a disaggregated RAN architecture) that may be configured to utilize a protocol stack that is physically or logically distributed between two or more network entities 105, such as an integrated access backhaul (IAB) network, an open RAN (O-RAN) (e.g., a network configuration sponsored by the O-RAN Alliance), or a virtualized RAN (vRAN) (e.g., a cloud RAN (C-RAN)). For example, the network entity 105 may include one or more of the following: a central unit (CU) 160, a distributed unit (DU) 165, a radio unit (RU) 170, a RAN intelligent controller (RIC) 175 (e.g., a near real-time RIC (near RT RIC), a non-real-time RIC (non-RT RIC)), a service management and orchestration (SMO) 180 system, or any combination thereof. The RU 170 may also be referred to as a radio head, a smart radio head, a remote radio head (RRH), a remote radio unit (RRU), or a transmit receive point (TRP). One or more components of the network entity 105 in the decomposed RAN architecture may be co-located, or one or more components of the network entity 105 may be located in distributed locations (e.g., separate physical locations). In some examples, one or more network entities 105 of the decomposed RAN architecture may be implemented as virtual units (e.g., virtual CU (VCU), virtual DU (VDU), virtual RU (VRU)).

[0037] The functional split between CU 160, DU 165, and RU 170 is flexible and may support different functionalities, depending on which functions (e.g., network layer functions, protocol layer functions, baseband functions, RF functions, and any combination thereof) are performed at CU 160, DU 165, or RU 170. For example, a functional split of a protocol stack may be employed between CU 160 and DU 165 such that CU 160 may support one or more layers of a protocol stack and DU 165 may support one or more different layers of a protocol stack. In some examples, CU 160 may host higher protocol layer (e.g., layer 3 (L3), layer 2 (L2)) functionality and signaling (e.g., radio resource control (RRC), service data adaptation protocol (SDAP), packet data convergence protocol (PDCP)). The CU 160 may be connected to one or more DUs 165 or RUs 170, and the one or more DUs 165 or RUs 170 may host lower protocol layers, such as layer 1 (L1) (e.g., physical (PHY) layer) or L2 (e.g., radio link control (RLC) layer, medium access control (MAC) layer) functionality and signaling, and may each be at least partially controlled by the CU 160. Additionally or alternatively, a functional split of the protocol stack may be employed between the DU 165 and the RU 170, such that the DU 165 may support one or more layers of the protocol stack, and the RU 170 may support one or more different layers of the protocol stack. The DU 165 may support one or more different cells (e.g., via one or more RUs 170). In some cases, the functional split between CU 160 and DU 165 or between DU 165 and RU 170 can be within the protocol layer (e.g., some functions of the protocol layer can be performed by one of CU 160, DU 165, or RU 170, while other functions of the protocol layer are performed by different ones of CU 160, DU 165, or RU 170). CU 160 can be further functionally split into CU control plane (CU-CP) and CU user plane (CU-UP) functions. CU 160 can be connected to one or more DUs 165 via midhaul communication links 162 (e.g., F1, F1-c, F1-u), and DU 165 can be connected to one or more RUs 170 via fronthaul communication links 168 (e.g., open fronthaul (FH) interface). In some examples, midhaul communication link 162 or fronthaul communication link 168 may be implemented based on an interface (e.g., a channel) between layers of a protocol stack supported by respective network entities 105 that communicate via such communication links.

[0038] In some wireless communication systems (e.g., wireless communication system 100), infrastructure and spectrum resources for radio access may support wireless backhaul link capabilities to supplement wired backhaul connections, thereby providing an IAB network architecture (e.g., to core network 130). In some cases, in an IAB network, one or more network entities 105 (e.g., IAB nodes 104) may be partially controlled by each other. One or more IAB nodes 104 may be referred to as donor entities or IAB donors. One or more DUs 165 or one or more RUs 170 may be controlled in part by one or more CUs 160 associated with a donor network entity 105 (e.g., donor base station 140). One or more donor network entities 105 (e.g., IAB donors) may communicate with one or more additional network entities 105 (e.g., IAB nodes 104) via supported access and backhaul links (e.g., backhaul communication links 120). The IAB node 104 may include an IAB mobile terminal (IAB-MT) controlled (e.g., scheduled) by a coupled IAB donor's DU 165. The IAB-MT may include an independent set of antennas for relaying communications with the UE 115, or may share the same antennas of the IAB node 104 (e.g., of the RU 170) for access via the DU 165 of the IAB node 104 (e.g., referred to as a virtual IAB-MT (vIAB-MT)). In some examples, the IAB node 104 may include a DU 165 that supports communication links with additional entities (e.g., IAB node 104, UE 115) within a relay chain or configuration (e.g., downstream) of the access network. In such cases, one or more components of the decomposed RAN architecture (e.g., one or more IAB nodes 104 or components of the IAB node 104) may be configured to operate according to the techniques described herein.

[0039] In the case where the techniques described herein are applied to the context of a disaggregated RAN architecture, one or more components of the disaggregated RAN architecture may be configured to support techniques for voice call hang detection and mitigation as described herein. For example, some operations described as being performed by a UE 115 or a network entity 105 (e.g., a base station 140) may additionally or alternatively be performed by one or more components of the disaggregated RAN architecture (e.g., an IAB node 104, a DU 165, a CU 160, a RU 170, a RIC 175, a SMO 180).

[0040] UE 115 may include or may be referred to as a mobile device, a wireless device, a remote device, a handheld device, or a subscriber device, or some other suitable term, where a "device" may also be referred to as a unit, a station, a terminal, or a client, etc. UE 115 may also include or may be referred to as a personal electronic device, such as a cellular phone, a personal digital assistant (PDA), a tablet computer, a laptop computer, or a personal computer. In some examples, UE 115 may include or may be referred to as a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or a machine type communication (MTC) device, etc., which may be implemented in various objects such as appliances or vehicles, meters, etc.

[0041] The UE 115 described herein may be capable of communicating with various types of devices such as other UEs 115 which may sometimes act as relays, as well as network entities 105 and network equipment including macro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations, etc. Figure 1 shown.

[0042] The UE 115 and the network entity 105 may wirelessly communicate with each other via one or more communication links 125 (e.g., access links) using resources associated with one or more carriers. The term "carrier" may refer to a collection of RF spectrum resources having a physical layer structure defined for supporting the communication link 125. For example, a carrier for the communication link 125 may include a portion of an RF spectrum band (e.g., a bandwidth portion (BWP)) that operates according to one or more physical layer channels for a given radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR). Each physical layer channel may carry acquisition signaling (e.g., synchronization signals, system information), control signaling for coordinating carrier operations, user data, or other signaling. The wireless communication system 100 may support communications with the UE 115 using carrier aggregation or multi-carrier operation. Depending on the carrier aggregation configuration, the UE 115 may be configured to have multiple downlink component carriers and one or more uplink component carriers. Carrier aggregation may be used for both frequency division duplex (FDD) and time division duplex (TDD) component carriers. Communication between the network entity 105 and other devices may refer to communication between these devices and any portion (e.g., entity, sub-entity) of the network entity 105. For example, the terms "send," "receive," or "communicate" when referring to the network entity 105 may refer to any portion of a network entity 105 (e.g., base station 140, CU 160, DU 165, RU 170) of a RAN communicating with another device (e.g., directly or via one or more other network entities 105).

[0043] The signal waveform transmitted via the carrier may include multiple subcarriers (e.g., using multi-carrier modulation (MCM) techniques, such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM)). In a system using MCM technology, a resource element may refer to a symbol period (e.g., the duration of a modulation symbol) and a resource of a subcarrier, in which case the symbol period and the subcarrier spacing may be inversely related. The number of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme, the coding rate of the modulation scheme, or both), so that a relatively high number of resource elements (e.g., in the transmission duration) and a relatively high order modulation scheme may correspond to a relatively high communication rate. Wireless communication resources may refer to a combination of RF spectrum resources, time resources, and spatial resources (e.g., spatial layers or beams), and the use of multiple spatial resources may increase the data rate or data integrity used for communication with UE 115.

[0044] The time interval for the network entity 105 or the UE 115 may be expressed as a multiple of a basic time unit, which may be, for example, a sampling period T s =1 / (Δf max ·N f ) seconds, for which Δf max It can represent the supported subcarrier spacing, and N f The supported discrete Fourier transform (DFT) size may be indicated. The time intervals of the communication resources may be organized according to radio frames each having a specified duration (e.g., 10 milliseconds (ms)). Each radio frame may be identified by a system frame number (SFN) (e.g., ranging from 0 to 1023).

[0045] Each frame may include multiple consecutively numbered subframes or time slots, and each subframe or time slot may have the same duration. In some examples, the frame may be divided into subframes (e.g., in the time domain), and each subframe may be further divided into a certain number of time slots. Alternatively, each frame may include a variable number of time slots, and the number of time slots may depend on the subcarrier spacing. Each time slot may include a certain number of symbol periods (e.g., depending on the length of the cyclic prefix appended in front of each symbol period). In some wireless communication systems 100, the time slot may be further divided into a plurality of micro time slots associated with one or more symbols. Excluding the cyclic prefix, each symbol period may be associated with one or more (e.g., N f The duration of a symbol period may depend on the subcarrier spacing or the operating frequency band.

[0046] A subframe, slot, mini-slot, or symbol may be the smallest scheduling unit (e.g., in the time domain) of the wireless communication system 100 and may be referred to as a transmission time interval (TTI). In some examples, the TTI duration (e.g., the number of symbol periods in a TTI) may be variable. Additionally or alternatively, the smallest scheduling unit of the wireless communication system 100 may be dynamically selected (e.g., in a burst of a shortened TTI (sTTI)).

[0047] According to various techniques, physical channels may be multiplexed using carriers for communication. Physical control channels and physical data channels may be multiplexed for signaling via downlink carriers, for example, using one or more of a time division multiplexing (TDM) technique, a frequency division multiplexing (FDM) technique, or a hybrid TDM-FDM technique. A control region (e.g., a control resource set (CORESET)) of a physical control channel may be defined by a set of symbol periods and may extend across a system bandwidth of a carrier or a subset of that system bandwidth. One or more control regions (e.g., CORESETs) may be configured for a set of UEs 115. For example, one or more UEs in UE 115 may monitor or search a control region to obtain control information according to one or more search space sets, and each search space set may include one or more control channel candidates in one or more aggregation levels arranged in a cascaded manner. The aggregation level of a control channel candidate may refer to the amount of control channel resources (e.g., control channel elements (CCEs)) associated with coded information for a control information format having a given payload size. The search space sets may include a common search space set configured for transmitting control information to multiple UEs 115 , and a UE-specific search space set for transmitting control information to a specific UE 115 .

[0048] The network entity 105 may provide communication coverage via one or more cells (e.g., macro cells, small cells, hot spots, or other types of cells, or any combination thereof). The term "cell" may refer to a logical communication entity used to communicate with the network entity 105 (e.g., using a carrier), and may be associated with an identifier (e.g., a physical cell identifier (PCID), a virtual cell identifier (VCID), or other cell identifier) ​​used to distinguish adjacent cells. In some examples, a cell may also refer to a coverage area 110 or a portion of a coverage area 110 (e.g., a sector) on which the logical communication entity operates. Depending on various factors such as the capabilities of the network entity 105, such cells may range from smaller areas (e.g., structures, subsets of structures) to larger areas. For example, a cell may be or may include a building, a subset of a building, or an external space between or overlapping coverage areas 110, and the like.

[0049] A macro cell generally covers a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access to a UE 115 that has a service subscription with a network provider that supports the macro cell. A small cell may be associated with a lower power network entity 105 (e.g., a lower power base station 140) than a macro cell, and the small cell may operate using the same or different (e.g., licensed, unlicensed) frequency band as the macro cell. A small cell may provide unrestricted access to a UE 115 that has a service subscription with a network provider, or may provide restricted access to a UE 115 associated with a small cell (e.g., a UE 115 in a closed subscriber group (CSG), a UE 115 associated with a user in a home or office). A network entity 105 may support one or more cells, and may also use one or more component carriers to support communications via one or more cells.

[0050] In some examples, a carrier may support multiple cells, and different cells may be configured according to different protocol types (e.g., MTC, narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB)) that may provide access to different types of devices.

[0051] In some examples, the network entities 105 (e.g., base stations 140, RUs 170) may be mobile and thus provide communication coverage for mobile coverage areas 110. In some examples, different coverage areas 110 associated with different technologies may overlap, but the different coverage areas 110 may be supported by the same network entity 105. In some other examples, overlapping coverage areas 110 associated with different technologies may be supported by different network entities 105. The wireless communication system 100 may include, for example, a heterogeneous network in which different types of network entities 105 provide coverage for various coverage areas 110 using the same or different radio access technologies.

[0052] The wireless communication system 100 may be configured to support ultra-reliable communication or low-latency communication or various combinations thereof. For example, the wireless communication system 100 may be configured to support ultra-reliable low-latency communication (URLLC). UE 115 may be designed to support ultra-reliable or low-latency or critical functions. Ultra-reliable communication may include private communication or group communication, and may be supported by one or more services (such as push-to-talk, video, or data). Support for ultra-reliable, low-latency functions may include prioritization of services, and such services may be used for public safety or general commercial applications. The terms ultra-reliable, low-latency, and ultra-reliable low-latency may be used interchangeably herein.

[0053] In some examples, a UE 115 may be configured to support communication directly with other UEs 115 via a device-to-device (D2D) communication link 135 (e.g., according to a peer-to-peer (P2P), D2D, or sidelink protocol). In some examples, one or more UEs 115 in a group that are performing D2D communication may be within a coverage area 110 of a network entity 105 (e.g., a base station 140, a RU 170), which may support aspects of such D2D communication configured (e.g., scheduled) by the network entity 105. In some examples, one or more UEs 115 in such a group may be outside of the coverage area 110 of the network entity 105, or may otherwise be unable or not configured to receive transmissions from the network entity 105. In some examples, a group of UEs 115 communicating via D2D communication may support a one-to-many (1:M) system, in which each UE 115 transmits to each of the other UEs 115 in the group. In some examples, network entity 105 may facilitate scheduling of resources for D2D communications. In some other examples, D2D communications may be performed between UEs 115 without involving network entity 105.

[0054] The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The core network 130 may be an evolved packet core (EPC) or a 5G core (5GC), which may include at least one control plane entity (e.g., a mobility management entity (MME), an access and mobility management function (AMF)) for managing access and mobility and at least one user plane entity (e.g., a serving gateway (S-GW), a packet data network (PDN) gateway (P-GW), or a user plane function (UPF)) for routing packets or interconnecting to an external network. The control plane entity may manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management of UE 115 served by a network entity 105 (e.g., a base station 140) associated with the core network 130. User IP packets may be delivered through the user plane entity, which may provide IP address allocation and other functions. The user plane entity may be connected to the IP service 150 of one or more network operators. IP services 150 may include access to the Internet, an intranet, an IP Multimedia Subsystem (IMS), or packet-switched streaming services.

[0055] The wireless communication system 100 may operate using one or more frequency bands that may be in the range of 300 megahertz (MHz) to 300 gigahertz (GHz). Generally speaking, the region from 300 MHz to 3 GHz is referred to as the ultra-high frequency (UHF) region or decimeter band because the wavelength ranges from about one decimeter to one meter in length. UHF waves may be blocked or redirected by buildings and environmental features (which may be referred to as clusters), but these waves may be sufficient to penetrate structures so that macro cells provide services to UEs 115 located indoors. Communications using UHF waves may be associated with smaller antennas and shorter ranges (e.g., less than 100 kilometers) compared to communications using lower frequencies and longer waves in the high frequency (HF) or very high frequency (VHF) portions of the spectrum below 300 MHz.

[0056] The wireless communication system 100 may utilize licensed and unlicensed RF spectrum bands. For example, the wireless communication system 100 may use unlicensed bands (such as the 5 GHz Industrial, Scientific, and Medical (ISM) band) to employ license assisted access (LAA), LTE unlicensed (LTE-U) radio access technology, or NR technology. When operating using unlicensed RF spectrum bands, devices such as network entity 105 and UE 115 may employ carrier sensing for conflict detection and avoidance. In some examples, operations using unlicensed bands may be based on carrier aggregation configuration (e.g., LAA) in conjunction with component carriers operating using licensed bands. Operations using unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, and the like.

[0057] The network entity 105 (e.g., base station 140, RU 170) or UE 115 may be equipped with multiple antennas that can be used to employ technologies such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communication, or beamforming. The antennas of the network entity 105 or UE 115 may be located in one or more antenna arrays or antenna panels, which may support MIMO operations or transmit or receive beamforming. For example, one or more base station antennas or antenna arrays may be co-located at an antenna assembly, such as an antenna tower. In some examples, antennas or antenna arrays associated with the network entity 105 may be located at different geographical locations. The network entity 105 may include an antenna array having a collection of multiple rows and columns of antenna ports that the network entity 105 can use to support beamforming for communications with the UE 115. Similarly, the UE 115 may include one or more antenna arrays that may support various MIMO or beamforming operations. Additionally or alternatively, the antenna panel may support RF beamforming for signals sent via the antenna ports.

[0058] Beamforming (which may also be referred to as spatial filtering, directional transmission, or directional reception) is a signal processing technique that may be used at a transmitting device or a receiving device (e.g., a network entity 105, a UE 115) to shape or direct an antenna beam (e.g., a transmit beam, a receive beam) along a spatial path between the transmitting device and the receiving device. Beamforming may be achieved by combining signals conveyed via antenna elements of an antenna array so that some signals propagating along a particular orientation relative to the antenna array experience constructive interference, while other signals experience destructive interference. Adjustments to signals conveyed via antenna elements may include the transmitting device or the receiving device applying an amplitude offset, a phase offset, or both to signals carried via antenna elements associated with the device. Adjustments associated with each of these antenna elements may be defined by a set of beamforming weights associated with a particular orientation (e.g., relative to the antenna array of the transmitting device or the receiving device or relative to some other orientation).

[0059] The wireless communication system 100 may be a packet-based network that operates according to a layered protocol stack. In the user plane, communications at the bearer or PDCP layer may be IP-based. The RLC layer may perform packet segmentation and reassembly to communicate via logical channels. The MAC layer may perform priority processing and multiplexing of logical channels into transport channels. The MAC layer may also implement error detection techniques, error correction techniques, or both to support retransmission to improve link efficiency. In the control plane, the RRC layer may provide the establishment, configuration, and maintenance of an RRC connection that supports a radio bearer for user plane data between the UE 115 and the network entity 105 or the core network 130. The PHY layer may map a transport channel to a physical channel.

[0060] In some cases, UE 115 may establish a packet-based voice call with a peer device (e.g., a different UE 115 or other packet-based voice call device such as an Internet-connected VoIP phone) via a wireless communication system. The packet-based voice call may be evaluated by UE 115 at one or more times to determine the presence of a voice call pause. In the case of a voice call pause being detected, one or more mitigation actions may be taken, such as triggering a handover to a different serving cell at the physical layer of UE 115, which may help avoid the termination of the call and help enhance the user experience. In some cases, a voice call pause may be identified based on a threshold of a voice pause, wherein the threshold is based on the number of voice call packets expected to be received during an active call state of a packet-based voice call during an evaluation period. In the case where the number of voice call packets received during the evaluation period is below a threshold, a handover from a first serving cell to a different serving cell may be initiated.

[0061] Figure 2An example of a wireless communication system 200 supporting techniques for voice call hang detection and mitigation according to one or more aspects of the present disclosure is illustrated. The wireless communication system 200 may include a network entity 105-a and a UE 115-a, which may be represented as shown in FIG. Figure 1 1 and 115. In this example, the UE 115-a may communicate with the network entity 105-a within the coverage area 110-a via a downlink carrier 205 and an uplink carrier 210 (which may be different carriers operating using FDD, or the same carrier operating using TDD, for example).

[0062] In some cases, UE 115-a may communicate with the network entity 105-a and associated networks (e.g., Figure 1 130) with a peer device (e.g., another UE, a VoIMS-enabled device, etc.). In some cases, the packet-based voice call may be managed at an RTP application at an application layer of the UE 115-a, and the UE 115-a may receive downlink voice call packets 215 (e.g., RTP packets, RTCP reports, or both from the peer device) via the downlink carrier 205. As part of the packet-based voice call, the UE 115-a may send uplink voice call packets 220 (e.g., RTP packets, RTCP reports, or both from the UE 115-a) via the uplink carrier 210. According to various aspects as discussed herein, the UE 115-a may evaluate the downlink voice call packets 215 and determine the presence or absence of a voice call pause. In the event that a voice call pause is detected, the UE 115-a may send a measurement report 225 to the network entity 105-a that triggers a handover of the UE 115-a. In some cases, the network entity 105-a may send a handover command 230 to the UE 115-a to trigger a handover from a first serving cell to a different serving cell or to a different RAT (e.g., served by a different network entity in a wireless communication network different from the wireless communication system 200).

[0063] In some cases, a threshold for a voice pause for a packet-based voice call may be identified based at least in part on the number of voice call packets expected to be received during an active call state of the packet-based voice call during an evaluation period. In response to the number of voice call packets received from a peer device during the evaluation period being below a threshold, UE 115-a may trigger a handover. For example, UE 115-a may receive an indication of the number of packets sent from a peer device for a packet-based voice call (e.g., in an RTCP transmitter report (SR)), and may initiate a handover based at least in part on the ratio of the number of voice call packets received from a peer device to the number of packets sent from a peer device during the evaluation period. Various examples of setting a threshold and determining the presence of a voice call pause are discussed herein.

[0064] For example, the threshold may be adaptive based on the number of voice packets indicated in the RTCP SR, the SID interval (e.g., a SID frame is sent at the SID interval to indicate that there is no voice to be sent from the peer device), a default mixed voice mode (e.g., 40% talking, 40% listening, 20% silence), or any combination thereof. In some cases, the threshold may be determined for each evaluation period based on the estimated voice activity, and if the number of voice packets received during the evaluation period is less than the threshold (e.g., if less than 20% of the expected voice packets are received), the UE 115-a may enter a voice pause mode. In the event that a voice call is determined to have been paused, the RTP application at the application layer may trigger the UE 115-a lower layers (e.g., RRC / MAC layers) to initiate a handover of the UE 115-a to a different serving cell. In some cases, the lower layers may force the sending of a measurement report 225 to initiate the handover, such as by triggering the sending of a measurement report 225 to initiate the handover by making a one-time adjustment to the RSRP increment.

[0065] Figure 3 An example of a flowchart 300 supporting techniques for voice call stall detection and mitigation in accordance with one or more aspects of the present disclosure is illustrated. The flowchart 300 may be found at Figure 1 and Figure 2 For example, flowchart 300 may illustrate operations at a UE (e.g., UE 115), which may be as described in reference Figure 1 and Figure 2 Examples of corresponding devices described. The following alternative examples can be implemented, in which some steps are performed in a different order than described or not performed at all. In some cases, the operation may include additional features not mentioned below, or additional operations may be added.

[0066] At 305, the UE may start a voice call stall evaluation based on the presence of an active voice call in a connected state. In some cases, the voice call stall evaluation may be performed at an upper layer (e.g., an application layer) of the UE, such as an RTP application operating at the application layer of the UE. In some cases, the voice call stall evaluation is performed for an active voice call, and not for a voice call in a held state.

[0067] At 310, the UE may determine whether RTCP information with a transmitter report (SR) is received at the UE. In some cases, the RTP application at the UE may receive the RTCP SR and determine various information items from the SR, such as an identification of the transmitter, one or more timestamps associated with the RTP communication, a packet count of the transmitter (e.g., a 32-bit field in the SR indicating the total number of RTP data packets sent by the transmitter since the start of transmission until the time the SR was generated), an octet count of the transmitter, or any combination thereof.

[0068] At 315, if it is determined that RTCP with SR is not received, the UE may determine whether RTCP with SR is not received within a time threshold associated with the SR (e.g., 6 seconds). If less than the time threshold has passed since the previous RTCP SR was received, the UE continues the operation at box 310. At 320, if the time threshold since the RTCP SR was received meets or exceeds the time threshold, the UE may apply a default hybrid voice mode to the RTP packets received during the evaluation period. In some cases, the hybrid voice mode may be 40% speaking, 40% listening, and 20% silence. In some cases, the hybrid voice mode may be adaptive based on a pattern associated with the voice call (e.g., since the start of the voice call) or a pattern of the most recent portion of the voice call (e.g., a pattern of the previous 10 second period). In some cases, machine learning (ML) or artificial intelligence (AI) techniques may be used to determine the adaptive hybrid voice mode.

[0069] At 325, the UE may compare the received RTP packet with a threshold value (e.g., threshold value M). In some cases, the threshold value may be an adaptive threshold value that is separately identified for each evaluation period, as discussed in various aspects of this document. At 330, the UE determines whether the number of RTP packets for the voice call is below the threshold value. At 335, if the number of RTP packets received during the evaluation period is less than the threshold value, the UE may identify that the voice call is paused. At 340, if the number of RTP packets received during the evaluation period is equal to or higher than the threshold value, the UE may identify that the voice call is not in a voice call pause. At 345, the UE may indicate to the access stratum (AS) layer whether the call state has changed (e.g., if the call state is a voice call pause, this may initiate the sending of a measurement report to trigger a handover of the UE). Operations may then continue at 310 for subsequent evaluation periods.

[0070] At 350, in the event that the UE receives an RTCP with an SR at 310, the UE determines whether the gap with the previously received RTCP with an SR is less than a time period (e.g., 5 seconds). If the gap with the previously received RTCP is less than the time period, the UE may continue operation at 310. At 355, if the gap with the previously received RTCP meets or exceeds the time period, the UE may calculate a converted RTP activity ratio. In some cases, the converted RTP activity ratio may be calculated based on a total expected number of RTP packets in an evaluation window (e.g., based on a packet count in an RTCP SR). In some cases, the converted RTP activity ratio may be calculated as an expected number of RTP packets (e.g., based on a difference in packet counts between RTCP SRs at the beginning and end of an evaluation period) divided by an evaluation window size that is adjusted based on the voice packets and SID intervals reported in the RTCP SR. In one example, such a ratio may be calculated as:

[0071] Converted RTP activity ratio = expected number of RTPs in the evaluation window / (evaluation window size * 50) * (X / 160ms)

[0072] Where the evaluation window size is 5s to 6s based on RTCP reception, the expected number of RTPs in the evaluation window is the difference between the two "transmitter's packet counts" in the RTCP SR at the start and end of the evaluation window, 50 is the total number of RTPs in one second if all RTP packets are voice packets, X is the SID interval, and X / 160 provides a conversion to 160ms SID interval.

[0073] For example, if the evaluation window size = 5s, when the SID interval = 160ms and the peer UE is not talking (e.g., the evaluation window is all SID frames, corresponding to 31.25 SID frames), the converted RTP activity ratio = 31 / 250*(160ms / 160ms) = 12.4%. In another example, the evaluation window side is 5 seconds and the SID interval is one second, and the peer UE is not talking (e.g., the evaluation window is all SID frames, corresponding to 5 SID frames), the converted RTP activity ratio = 5 / 250*(1000ms / 160ms) = 12.5%. In some cases, the SID interval (X) may be determined based on a coding rate associated with a voice call (e.g., Adaptive Multi-Rate (AMR), AMR-WB, Enhanced Voice Service (EVS) without Discontinuous Reception (DRX) may have X=160 ms; and EVS with DTX may set X to one of the most recently received SID interval, the average SID interval in an evaluation window, the maximum SID interval in an evaluation window, or the minimum SID interval in an evaluation window). In some cases, when the SID interval (X) becomes higher, fewer RTP packets are expected to be received, which results in a lower pause threshold and a more stringent trigger indicating a pause; and when the SID interval (X) becomes lower, more RTP packets are expected to be received, which results in a higher pause threshold and a less stringent trigger indicating a pause.

[0074] At 360, the UE may determine whether the calculated converted RTP activity ratio is less than 13%. In some cases, an RTP activity ratio equal to or higher than 13% may indicate that the evaluation period is not a full SID period. At 365, if it is determined that the converted RTP activity ratio is less than 13%, the UE may identify that the voice call is not in a voice call pause (e.g., if the peer user is not speaking and the evaluation period includes all SID frames, a pause is not triggered). If it is determined at 360 that the converted RTP activity ratio is equal to or higher than 13%, the operation at 325 may be performed.

[0075] Thus, using such techniques, voice call pauses can be evaluated based on an adaptive threshold calculated for each evaluation period, wherein the UE determines that the voice call is paused when the number of RTP packets received in the evaluation window is less than a threshold (M). If the evaluation is triggered by RTCP with SR (e.g., when the gap with the previous RTCP with SR is 5 seconds or more), the UE calculates the converted RTP activity ratio and calculates the number of expected RTP packets in the evaluation window based on the packet count of the transmitter in the RTCP SR. The UE can calculate the threshold (M) based on the number of expected RTP packets and the target RTP loss rate (e.g., a loss rate of 80%, so that if the number of received RTP packets is less than 20% of the number of expected RTP packets, a pause is identified). In some cases, the number of voice packets received in the evaluation window is determined by counting the received RTP packets with RTP timestamps in the RTP timestamps of the RTCP SR packets that fall at the boundary of the evaluation window. In addition, in the case where the converted RTP activity ratio is less than 13%, the UE declares no pause because the peer side is not talking. However, if no SR report is received, the UE may perform a voice call hang evaluation based on expiration of the timer, wherein a mixed voice mode (e.g., 40% listening, 20% silence, 40% talking, or a 40 / 20 / 40 mixed mode) is assumed for the evaluation window, and the threshold is determined based on the assumed mixed voice mode.

[0076] For example, with such a mixed voice mode, the expected number of voice packets (in a 6s evaluation window with a 20ms frame rate) will be: 2400ms / 20ms+3600ms / Xms=120+3600 / X. Table 1 illustrates examples of thresholds (M) for different scenarios with a 20ms frame, a five-second evaluation window when RTCP SR is available, and a six-second evaluation window when RTCP SR is not available:

[0077]

[0078] Table 1 - M values ​​with and without RTCP SR, and RTP loss rate targets

[0079] Table 2 illustrates examples of threshold values ​​(M) for different scenarios with different SID intervals with a five-second evaluation window when RTCP SR is available:

[0080]

[0081] Table 2 - M values ​​and RTP loss rate targets in different scenarios based on RTCP SR

[0082] In some cases, after detecting a voice call pause, the UE may trigger a handover or movement to another RAT (e.g., a second RAT) or to another cell of the RAT for initiating a voice call (e.g., a first RAT). In some cases, when no cell in the first RAT is available for handover, the UE may trigger a handover or movement to the second RAT. In some cases, an inter-RAT handover or an intra-RAT handover may be triggered by sending a measurement report, which triggers the handover of the UE when received at the network entity. In some cases, the UE may send a measurement report by overriding the measurement report criteria that triggers the sending of the measurement report. For example, the UE may be configured to send a measurement report when the reference signal received power (RSRP) of the target cell exceeds the RSRP of the serving cell by 3 dB, and in the case of an indication of a voice call pause, the value may be adjusted so that the measurement report is sent if the RSRP of the target cell exceeds the RSRP of the serving cell by at least -3 dB. Therefore, in the case of detecting a voice call pause, a measurement report that triggers a handover may be sent more quickly. The network entity that receives the measurement report from the UE may then trigger a handover procedure.

[0083] 4A to 4D An example of a timing diagram 400 that supports techniques for voice call stall detection and mitigation in accordance with one or more aspects of the present disclosure is illustrated. The timing diagram 400 may be found at reference Figure 1 and Figure 2 The present invention is implemented in various aspects of the present disclosure.

[0084] exist Figure 4A In the first example timing diagram 400-a of FIG. 4 , a first RTCP SR 405 and a second RTCP SR 410 may be received at a UE, where a voice call hang evaluation window 415 is five seconds for an evaluation based on an RTCP SR. In this example, consecutive RTCP SRs 405 and 410 may be sent at five-second intervals, and the UE may evaluate the voice call hang based on the received SRs.

[0085] exist Figure 4B In a second example timing diagram 400-b of FIG. 400, a first RTCP SR 405 and a second RTCP SR 410 may be received at a UE, where a voice call hang evaluation window 415 is five seconds based on the RTCP SR. In this example, the SRs are sent at one-second intervals, and multiple additional RTCP SRs 420-a to 420-e may be sent. In such a case, the UE may evaluate the voice call hang based on the first RTCP SR 405 and the most recently received SR (in this example, the second RTCP SR 410) before the end of the evaluation window 415.

[0086] exist Figure 4CIn the third example timing diagram 400-c of FIG. 4 , a first RTCP SR 405 and a second RTCP SR 410 may be received at a UE having a voice call stall evaluation window 430 of six seconds based on no RTCP SR reception within the evaluation window 430. In this example, the first RTCP SR 405 is received at the beginning of the voice call stall evaluation window 430, but a time period 425 greater than six seconds elapses before the second RTCP SR 410 is received. In such a case, a forced evaluation 435 may be performed at the end of the voice call stall evaluation window 430. Furthermore, in such a case, the UE may again evaluate the voice call stall based on receiving the second RTCP SR 410.

[0087] exist Figure 4D In the fourth example timing diagram 400-d of , no RTCP SR may be received at the UE, and based on no RTCP SR reception within the evaluation window 430, a first forced voice call pause evaluation 440 may be performed with a six-second voice call pause evaluation window 430. In this example, no RTCP SR is received within the six-second voice call pause evaluation window 430, and the UE may perform a second forced voice call pause evaluation 445 based on expiration of the voice call pause evaluation window 430.

[0088] Figure 5 An example of a process flow 500 supporting techniques for voice call hang detection and mitigation in accordance with one or more aspects of the present disclosure is illustrated. The process flow 500 may include reference Figures 1 to 4D For example, process flow 500 may illustrate communication between UE 115-b and network entity 105-b, which may be reference Figure 1 and Figure 2 Examples of corresponding devices described. The following alternative examples can be implemented, in which some steps are performed in a different order than described or not performed at all. In some cases, the steps may include additional features not mentioned below, or further steps may be added.

[0089] The network entity 105-b and the UE 115-b may establish a connection for communication at 505. In some cases, the connection establishment may be performed according to a connection establishment technique for the wireless communication system (eg, via an RRC connection establishment or re-establishment procedure).

[0090] At 510, the network entity 105-b may send information indicating the voice call initiation to the UE 115-b. In some cases, the voice call initiation may be provided by an RTP application running at a higher layer (e.g., at the RTP layer or application layer) at the UE 115-b and the network entity 105-b. At 515 through 520, the UE 115-b and the network entity 105-b may exchange RTP packets, RTCP SRs, or any combination thereof as part of the packet-based voice call.

[0091] The UE may determine a voice call stall condition at 525. The voice call stall condition may be determined according to various techniques as discussed herein, such as an adaptive threshold based on RTP packets received in an evaluation period.

[0092] At 530, UE 115-b may modify measurement report triggering criteria based on the voice call stall condition. In some cases, the application layer indicating the voice call stall condition may cause lower layers (e.g., RRC layer or MAC layer) at UE 115-b to modify the measurement report triggering criteria. At 535, UE 115-b may format the measurement report to trigger a handover of the UE, and at 540, UE 115-b may send the measurement report to network entity 105-b.

[0093] At 545, the network entity 105-b may determine handover parameters for the UE 115-b in response to the measurement report. In some cases, the network entity 105-b may coordinate with another network entity (e.g., a target cell of the same RAT or a different RAT) to support a handover of the UE 115-b to the other network entity. At 550, the network entity 105-b may send a handover command to the UE 115-b indicating a handover to a different cell or RAT. At 555, the UE 115-b may initiate a handover procedure.

[0094] Figure 6 A block diagram 600 of a device 605 supporting techniques for voice call stall detection and mitigation according to one or more aspects of the present disclosure is shown. The device 605 may be an example of aspects of a UE 115 as described herein. The device 605 may include a receiver 610, a transmitter 615, and a communication manager 620. The device 605 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0095] The receiver 610 may provide means for receiving information (such as packets, user data, control information, or any combination thereof) associated with various information channels (e.g., control channels, data channels, information channels related to techniques for voice call stall detection and mitigation). The information may be communicated to other components of the device 605. The receiver 610 may utilize a single antenna or a collection of multiple antennas.

[0096] The transmitter 615 may provide means for transmitting signals generated by other components of the device 605. For example, the transmitter 615 may transmit information (such as packets, user data, control information, or any combination thereof) associated with various information channels (e.g., control channels, data channels, information channels related to techniques for voice call stall detection and mitigation). In some examples, the transmitter 615 may be co-located with the receiver 610 in a transceiver module. The transmitter 615 may utilize a single antenna or a collection of multiple antennas.

[0097] The communication manager 620, the receiver 610, the transmitter 615, or various combinations thereof, or various components thereof, may be examples of means for performing various aspects of the techniques for voice call stall detection and mitigation as described herein. For example, the communication manager 620, the receiver 610, the transmitter 615, or various combinations thereof, or components thereof, may support methods for performing one or more of the functions described herein.

[0098] In some examples, the communication manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof may be implemented in hardware (e.g., in a communication management circuit). The hardware may include a processor, a digital signal processor (DSP), a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, a microcontroller, discrete gate or transistor logic, discrete hardware components, or any combination thereof that is configured to or otherwise supports components for performing the functions described in the present disclosure. In some examples, the processor and a memory coupled to the processor may be configured to perform one or more of the functions described herein (e.g., by executing instructions stored in the memory by the processor).

[0099] Additionally or alternatively, in some examples, the communication manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof may be implemented in code executed by a processor (e.g., as communication management software or firmware). If implemented in code executed by a processor, the functionality of the communication manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof may be performed by a general purpose processor (e.g., configured as or otherwise supporting means for performing the functionality described in the present disclosure), a DSP, a CPU, an ASIC, an FPGA, a microcontroller, or any combination of these or other programmable logic devices.

[0100] In some examples, communication manager 620 can be configured to perform various operations (e.g., receive, obtain, monitor, output, send) using or otherwise cooperating with receiver 610, transmitter 615, or both. For example, communication manager 620 can receive information from receiver 610, transmit information to transmitter 615, or be integrated in conjunction with receiver 610, transmitter 615, or both to obtain information, output information, or perform various other operations as described herein.

[0101] According to examples as disclosed herein, the communication manager 620 may support wireless communications at a UE. For example, the communication manager 620 may be configured to or otherwise support a component for establishing a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system. The communication manager 620 may be configured to or otherwise support a component for identifying a threshold for voice pauses for a packet-based voice call, the threshold being based on the number of voice call packets expected to be received during an active call state of a packet-based voice call during an evaluation period. The communication manager 620 may be configured to or otherwise support a component for initiating a handover of the UE from a first wireless network entity to a different wireless network entity in response to the number of voice call packets received from a peer device during the evaluation period being lower than the threshold for voice pauses for a packet-based voice call.

[0102] By including or configuring a communications manager 620 according to examples as described herein, the device 605 (e.g., a processor controlling the receiver 610, the transmitter 615, the communications manager 620, or a combination thereof or otherwise coupled thereto) may support techniques for voice call stall evaluation based on a threshold of a number of voice packets received during an evaluation period, which may mitigate gaps in voice calls to provide an enhanced user experience, enhanced reliability of packet-based voice calls, and / or provide enhanced network efficiency through fewer call failures or call terminations.

[0103] Figure 7A block diagram 700 of a device 705 supporting techniques for voice call stall detection and mitigation according to one or more aspects of the present disclosure is shown. The device 705 may be an example of aspects of the device 605 or UE 115 as described herein. The device 705 may include a receiver 710, a transmitter 715, and a communication manager 720. The device 705 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0104] The receiver 710 may provide means for receiving information (such as packets, user data, control information, or any combination thereof) associated with various information channels (e.g., control channels, data channels, information channels related to techniques for voice call stall detection and mitigation). The information may be communicated to other components of the device 705. The receiver 710 may utilize a single antenna or a collection of multiple antennas.

[0105] The transmitter 715 may provide means for transmitting signals generated by other components of the device 705. For example, the transmitter 715 may transmit information (such as packets, user data, control information, or any combination thereof) associated with various information channels (e.g., control channels, data channels, information channels related to techniques for voice call stall detection and mitigation). In some examples, the transmitter 715 may be co-located with the receiver 710 in a transceiver module. The transmitter 715 may utilize a single antenna or a collection of multiple antennas.

[0106] Device 705 or its various components may be examples of components for performing various aspects of the technology for voice call stall detection and mitigation as described herein. For example, communication manager 720 may include RTP call manager 725, voice call stall threshold manager 730, handover manager 735, or any combination thereof. Communication manager 720 may be an example of various aspects of communication manager 620 as described herein. In some examples, communication manager 720 or its various components may be configured to perform various operations (e.g., receive, obtain, monitor, output, send) using or otherwise cooperating with receiver 710, transmitter 715, or both. For example, communication manager 720 may receive information from receiver 710, transmit information to transmitter 715, or integrate with receiver 710, transmitter 715, or both in combination to obtain information, output information, or perform various other operations as described herein.

[0107] According to examples as disclosed herein, the communication manager 720 may support wireless communications at the UE. The RTP call manager 725 may be configured to or otherwise support a component for establishing a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system. The voice call pause threshold manager 730 may be configured to or otherwise support a component for identifying a threshold for voice pauses for a packet-based voice call, the threshold being based on the number of voice call packets expected to be received during an active call state of a packet-based voice call during an evaluation period. The handover manager 735 may be configured to or otherwise support a component for initiating a handover of the UE from the first wireless network entity to a different wireless network entity in response to the number of voice call packets received from the peer device during the evaluation period being lower than the threshold for voice pauses for the packet-based voice call.

[0108] Figure 8 A block diagram 800 of a communication manager 820 supporting techniques for voice call stall detection and mitigation according to one or more aspects of the present disclosure is shown. The communication manager 820 may be an example of aspects of the communication manager 620, the communication manager 720, or both as described herein. The communication manager 820 or its various components may be examples of components for performing various aspects of the techniques for voice call stall detection and mitigation as described herein. For example, the communication manager 820 may include an RTP call manager 825, a voice call stall threshold manager 830, a handover manager 835, an RCTP report manager 840, a voice call stall timer 845, a measurement report manager 850, or any combination thereof. Each of these components may communicate directly or indirectly with each other (e.g., via one or more buses).

[0109] According to examples as disclosed herein, the communication manager 820 may support wireless communications at the UE. The RTP call manager 825 may be configured to or otherwise support a component for establishing a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system. The voice call pause threshold manager 830 may be configured to or otherwise support a component for identifying a threshold for a voice pause for a packet-based voice call, the threshold being based on the number of voice call packets expected to be received during an active call state of a packet-based voice call during an evaluation period. The handover manager 835 may be configured to or otherwise support a component for initiating a handover of the UE from the first wireless network entity to a different wireless network entity in response to the number of voice call packets received from the peer device during the evaluation period being lower than the threshold for a voice pause for a packet-based voice call.

[0110] In some examples, RCTP report manager 840 may be configured to or otherwise support means for receiving from a peer device an indication of a number of packets sent from the peer device for a packet-based voice call, and wherein initiating handover of the UE is based on a ratio of the number of voice call packets received from the peer device to the number of packets sent from the peer device during an evaluation period. In some examples, the indication of the number of packets sent from the peer device is received in an RTCP transmitter report from the peer device.

[0111] In some examples, the voice call stall timer 845 may be configured or otherwise support means for determining that the time elapsed since receiving a report associated with a packet-based voice call exceeds a time threshold, and wherein the initiating UE handover is based on a number of voice call packets received from a peer device and an estimated number of voice call packets associated with an assumed mixed voice mode for an evaluation period. In some examples, the report associated with the packet-based voice call is an RTCP report. In some examples, the threshold is based on a SID interval of the packet-based voice call, wherein a higher SID interval has a lower threshold and a lower SID interval has a higher threshold.

[0112] In some examples, the voice call pause threshold manager 830 may be configured as or otherwise support a component for estimating, for an evaluation period, a ratio of an expected number of packets sent from a peer device during an evaluation period to a maximum number of packets that can be sent during the evaluation period, and wherein the threshold is determined based on the estimated ratio. In some examples, a value of the ratio less than the silence threshold indicates that the peer device is silent and the UE will refrain from triggering a handover during the evaluation period. In some examples, the number of voice call packets received from a peer device during the evaluation period is based on voice call packets having an RTP timestamp within the evaluation period.

[0113] In some examples, identifying a threshold for voice pauses and supporting initiating a handover of the UE is performed as part of a voice call pause evaluation, and in the method, the RCTP report manager 840 may be configured to or otherwise support a component for receiving at least one RTCP transmitter report indicating the number of RTP voice packets sent during an evaluation period. In some examples, identifying a threshold for voice pauses and supporting initiating a handover of the UE is performed as part of a voice call pause evaluation, and in the method, the voice call pause threshold manager 830 may be configured to or otherwise support a component for initiating a voice call pause evaluation in response to at least one RTCP transmitter report, wherein the threshold is based on the number of RTP voice packets indicated in the transmitter report and the number of SID frames within the evaluation period.

[0114] In some examples, the threshold for identifying voice pauses and supporting initiating a handover of the UE is performed as part of a voice call pause evaluation, and in the method, the voice call pause timer 845 may be configured as or otherwise support a component for determining that a certain period of time has passed since a previous evaluation period and no RTCP transmitter report has been received during the period of time. In some examples, the threshold for identifying voice pauses and supporting initiating a handover of the UE is performed as part of a voice call pause evaluation, and in the method, the voice call pause threshold manager 830 may be configured as or otherwise support a component for initiating a voice call pause evaluation in response to the determination, wherein the threshold is based on an assumed mixed voice mode of the packet-based voice call. In some examples, the threshold for identifying a voice pause for a packet-based voice call is an adaptive threshold based on the amount of voice activity present during the evaluation period.

[0115] In some examples, handover manager 835 may be configured or otherwise support means for receiving a handover message indicating a handover of a UE from a first wireless network entity to a second wireless network entity, wherein the second wireless network entity uses the same RAT as the first wireless network entity or a different RAT than the first wireless network entity.

[0116] In some examples, to support initiating a handover of the UE, the measurement report manager 850 may be configured as or otherwise support means for modifying criteria for sending a measurement report to the first wireless network entity that triggers the handover of the UE, wherein the measurement report is an inter-RAT measurement report or an intra-RAT measurement report based on measured channel conditions associated with wireless network entities of two or more RATs. In some examples, the handover manager 835 may be configured as or otherwise support means for sending a measurement report to the first wireless entity.

[0117] Fig. 9A diagram of a system 900 including a device 905 supporting techniques for voice call stall detection and mitigation according to one or more aspects of the present disclosure is shown. The device 905 may be an example of a device 605, a device 705, or a UE 115 as described herein, or include components thereof. The device 905 may communicate (e.g., wirelessly) with one or more network entities 105, one or more UEs 115, or any combination thereof. The device 905 may include components for two-way voice and data communications, including components for sending and receiving communications, such as a communication manager 920, an input / output (I / O) controller 910, a transceiver 915, an antenna 925, a memory 930, a code 935, and a processor 940. These components may be electronically communicated or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus 945).

[0118] I / O controller 910 can manage input signals and output signals of device 905. I / O controller 910 can also manage peripheral devices that are not integrated into device 905. In some cases, I / O controller 910 can represent a physical connection or port to an external peripheral device. In some cases, I / O controller 910 can utilize an operating system, such as Or another known operating system. Additionally or alternatively, I / O controller 910 may represent or interact with a modem, keyboard, mouse, touch screen, or similar device. In some cases, I / O controller 910 may be implemented as part of a processor (such as processor 940). In some cases, a user may interact with device 905 via I / O controller 910 or via hardware components controlled by I / O controller 910.

[0119] In some cases, the device 905 may include a single antenna 925. However, in some other cases, the device 905 may have more than one antenna 925, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 915 may communicate bidirectionally via one or more antennas 925, a wired or wireless link, as described herein. For example, the transceiver 915 may represent a wireless transceiver and may communicate bidirectionally with another wireless transceiver. The transceiver 915 may also include a modem for: modulating packets; providing the modulated packets to one or more antennas 925 for transmission; and demodulating packets received from one or more antennas 925. The transceiver 915 or the transceiver 915 and one or more antennas 925 may be examples of transmitters 615, transmitters 715, receivers 610, receivers 710, or any combination thereof or components thereof as described herein.

[0120] The memory 930 may include random access memory (RAM) and read-only memory (ROM). The memory 930 may store computer-readable, computer-executable code 935 including instructions that, when executed by the processor 940, cause the device 905 to perform various functions described herein. The code 935 may be stored in a non-transitory computer-readable medium, such as a system memory or another type of memory. In some cases, the code 935 may not be directly executed by the processor 940, but may (e.g., when compiled and executed) cause the computer to perform the functions described herein. In some cases, the memory 930 may also include, among other things, a basic I / O system (BIOS) that may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0121] The processor 940 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, the processor 940 may be configured to operate a memory array using a memory controller. In some other cases, the memory controller may be integrated into the processor 940. The processor 940 may be configured to execute computer-readable instructions stored in a memory (e.g., a memory 930) so that the device 905 performs various functions (e.g., functions or tasks that support techniques for voice call pause detection and mitigation). For example, the device 905 or a component of the device 905 may include a processor 940 and a memory 930 coupled to or coupled to the processor 940, and the processor 940 and the memory 930 are configured to perform the various functions described herein.

[0122] According to examples as disclosed herein, the communication manager 920 may support wireless communications at a UE. For example, the communication manager 920 may be configured to or otherwise support a component for establishing a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system. The communication manager 920 may be configured to or otherwise support a component for identifying a threshold for voice pauses for a packet-based voice call, the threshold being based on the number of voice call packets expected to be received during an active call state of a packet-based voice call during an evaluation period. The communication manager 920 may be configured to or otherwise support a component for initiating a handover of the UE from the first wireless network entity to a different wireless network entity in response to the number of voice call packets received from the peer device during the evaluation period being lower than the threshold for voice pauses for the packet-based voice call.

[0123] By including or configuring a communications manager 920 according to examples as described herein, the device 905 may support techniques for voice call stall evaluation based on a threshold of a number of voice packets received during an evaluation period, which may mitigate gaps in voice calls to provide an enhanced user experience, enhanced reliability of packet-based voice calls, and / or provide enhanced network efficiency through fewer call failures or call terminations.

[0124] In some examples, the communication manager 920 may be configured to perform various operations (e.g., receive, monitor, transmit) using or otherwise cooperating with the transceiver 915, one or more antennas 925, or any combination thereof. Although the communication manager 920 is illustrated as a separate component, in some examples, one or more functions described with reference to the communication manager 920 may be supported or performed by the processor 940, the memory 930, the code 935, or any combination thereof. For example, the code 935 may include instructions that can be executed by the processor 940 to cause the device 905 to perform various aspects of the techniques for voice call stall detection and mitigation as described herein, or the processor 940 and the memory 930 may be otherwise configured to perform or support such operations.

[0125] Fig.10 A flow chart illustrating a method 1000 for supporting techniques for voice call stall detection and mitigation according to one or more aspects of the present disclosure is shown. The operations of the method 1000 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1000 may be implemented by a UE or a component thereof as described in reference to Figures 1 to 9 The UE 115 described herein may be executed. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0126] At 1005, the method may include establishing a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system. The operations of 1005 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1005 may be performed as described in reference to Figure 8 The RTP call manager 825 is used to execute.

[0127] At 1010, the method may include identifying a threshold for voice pauses for the packet-based voice call, the threshold being based on a number of voice call packets expected to be received during an active call state for the packet-based voice call during an evaluation period. The operations of 1010 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1010 may be performed as described in reference to Figure 8 The voice call pause threshold manager 830 is used for execution.

[0128] At 1015, the method may include initiating a handover of the UE from the first wireless network entity to a different wireless network entity in response to a number of voice call packets received from the peer device during the evaluation period being below a threshold for a voice pause for a packet-based voice call. The operations of 1015 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1015 may be performed as described in reference to Figure 8 The handover manager 835 is used to perform the above operation.

[0129] In some cases, initiating the handover may include sending a measurement report that triggers the handover, and in one example, at 1020, the method may include modifying criteria for sending a measurement report to the first wireless network entity that triggers the handover of the UE, wherein the measurement report is an inter-RAT measurement report or an intra-RAT measurement report based on measured channel conditions associated with wireless network entities of two or more RATs. The operations of 1020 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1020 may be performed as described in reference to Figure 8 The measurement report manager 850 is used to perform the above-mentioned operation.

[0130] At 1025, in the event that the handover is initiated by such measurement report transmission, the method may include transmitting the measurement report to the first wireless entity. The operations of 1025 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1025 may be performed as described in reference to Figure 8 The handover manager 835 is used to perform the above operation.

[0131] At 1030, the method may include receiving a handover message indicating a handover of the UE from the first wireless network entity to the second wireless network entity, wherein the second wireless network entity uses the same RAT as the first wireless network entity or a different RAT than the first wireless network entity. The operations of 1030 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1030 may be performed as described in reference to Figure 8 The handover manager 835 is used to perform the above operation.

[0132] Fig.11 A flow chart illustrating a method 1100 for supporting techniques for voice call stall detection and mitigation according to one or more aspects of the present disclosure is shown. The operations of the method 1100 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1100 may be implemented by a UE or a component thereof as described in reference to Figures 1 to 9 The UE 115 described herein may be executed. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0133] At 1105, the method may include establishing a packet-based voice call with a peer device via a first wireless network entity of the wireless communication system. The operations of 1105 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1105 may be performed as described in reference to Figure 8 The RTP call manager 825 is used to execute.

[0134] At 1110, the method may include receiving from a peer device an indication of a number of packets sent from the peer device for a packet-based voice call. The operations of 1110 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1110 may be performed as described in reference to Figure 8 The RCTP report manager 840 is used to execute.

[0135] At 1115, the method may include identifying a threshold for voice pauses for the packet-based voice call, the threshold being based on a number of packets for the packet-based voice call sent from the peer device during the evaluation period. The operations of 1115 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1115 may be performed as described in reference to Figure 8 The voice call pause threshold manager 830 is used for execution.

[0136] At 1120, the method may include initiating a handover of the UE from the first wireless network entity to a different wireless network entity in response to a number of voice call packets received from the peer device during the evaluation period being below a threshold for a voice pause for a packet-based voice call. The operations of 1120 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1120 may be performed as described in reference to Figure 8 The handover manager 835 is described. In some cases, the handover of the initiating UE is based on the ratio of the number of voice call packets received from the peer device to the number of packets sent from the peer device during the evaluation period.

[0137] Fig.12 A flow chart illustrating a method 1200 for supporting techniques for voice call stall detection and mitigation according to one or more aspects of the present disclosure is shown. The operations of the method 1200 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1200 may be implemented by a UE or a component thereof as described in reference to Figures 1 to 9 The UE 115 described herein may be executed. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0138] At 1205, the method may include establishing a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system. The operations of 1205 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1205 may be performed as described in reference to Figure 8 The RTP call manager 825 is used to execute.

[0139] At 1210, the method may include determining that a time elapsed since receiving a report associated with a packet-based voice call exceeds a time threshold. The operations of 1210 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1210 may be performed as described in reference to Figure 8 The voice call pause timer 845 is used for execution.

[0140] At 1215, the method may include identifying a threshold for voice pauses for the packet-based voice call, the threshold being based on a number of voice call packets expected to be received during an active call state for the packet-based voice call during an evaluation period. The operations of 1215 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1215 may be performed as described in reference to Figure 8 The voice call pause threshold manager 830 is used for execution.

[0141] At 1220, the method may include initiating a handover of the UE from the first wireless network entity to a different wireless network entity in response to a number of voice call packets received from the peer device during the evaluation period being below a threshold for a voice pause for a packet-based voice call. The operations of 1220 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1220 may be performed as described in reference to Figure 8 The handover manager 835 is described. In some cases, the initiating UE's handover is based on the number of voice call packets received from the peer device and the estimated number of voice call packets associated with the assumed mixed voice mode for the evaluation period.

[0142] Fig.13 A flow chart illustrating a method 1300 for supporting techniques for voice call stall detection and mitigation according to one or more aspects of the present disclosure is shown. The operations of the method 1300 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1300 may be implemented by a UE or a component thereof as described in reference to Figures 1 to 9 The UE 115 described herein may be executed. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0143] At 1305, the method may include establishing a packet-based voice call with a peer device via a first wireless network entity of the wireless communication system. The operations of 1305 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1305 may be performed as described in reference to Figure 8 The RTP call manager 825 is used to execute.

[0144] At 1310, the method may include estimating, for the evaluation period, a ratio of an expected number of packets to be sent from the peer device during the evaluation period to a maximum number of packets that can be sent during the evaluation period. The operations of 1310 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1310 may be performed as described in reference to Figure 8 The voice call pause threshold manager 830 is used for execution.

[0145] At 1315, the method may include identifying a threshold for voice pauses for the packet-based voice call based on a number of voice call packets expected to be received based on the estimated ratio during an active call state for the packet-based voice call during an evaluation period. The operations of 1315 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1315 may be performed as described in reference to Figure 8 The voice call pause threshold manager 830 is used for execution.

[0146] At 1320, the method may include initiating a handover of the UE from the first wireless network entity to a different wireless network entity in response to a number of voice call packets received from the peer device during the evaluation period being below a threshold for a voice pause for a packet-based voice call. The operations of 1320 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1320 may be performed as described in reference to Figure 8 The handover manager 835 is used to perform the above operation.

[0147] Fig.14 A flow chart illustrating a method 1400 for supporting techniques for voice call stall detection and mitigation according to one or more aspects of the present disclosure is shown. The operations of the method 1400 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1400 may be implemented by a UE or a component thereof as described in reference to Figures 1 to 9 The UE 115 described herein may be executed. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0148] At 1405, the method may include establishing a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system. The operations of 1405 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1405 may be performed as described in reference to Figure 8 The RTP call manager 825 is used to execute.

[0149] At 1410, the method may include receiving at least one RTCP transmitter report indicating the number of RTP voice packets sent during the evaluation period. The operations of 1410 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1410 may be performed as described in reference to Figure 8 The RCTP report manager 840 is used to execute.

[0150] At 1415, the method may include initiating a voice call stall evaluation in response to at least one RTCP transmitter report. The operations of 1415 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1415 may be performed as described in reference to Figure 8 The voice call pause threshold manager 830 is used for execution.

[0151] At 1420, the method may include identifying a threshold for voice pauses for the packet-based voice call, the threshold being based on a number of voice call packets expected to be received during an active call state for the packet-based voice call during an evaluation period. The operations of 1420 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1420 may be performed as described in reference to Figure 8 The threshold is performed by the voice call pause threshold manager 830. In some cases, the threshold is based on the number of RTP voice packets indicated in the transmitter report and the number of SID frames within the evaluation period.

[0152] At 1425, the method may include initiating a handover of the UE from the first wireless network entity to a different wireless network entity in response to a number of voice call packets received from the peer device during the evaluation period being below a threshold for a voice pause for a packet-based voice call. The operations of 1425 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1425 may be performed as described in reference to Figure 8 The handover manager 835 is used to perform the above operation.

[0153] Fig.15 A flow chart illustrating a method 1500 for supporting techniques for voice call stall detection and mitigation according to one or more aspects of the present disclosure is shown. The operations of the method 1500 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1500 may be implemented by a UE or a component thereof as described in reference to Figures 1 to 9The UE 115 described herein may be executed. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0154] At 1505, the method may include establishing a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system. The operations of 1505 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1505 may be performed as described in reference to Figure 8 The RTP call manager 825 is used to execute.

[0155] At 1510, the method may include determining that a certain period of time has passed since a previous evaluation period and that no RTCP transmitter reports have been received during the period of time. The operations of 1510 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1510 may be performed as described in reference to Figure 8 The voice call pause timer 845 is used for execution.

[0156] At 1515, the method may include initiating a voice call pause evaluation in response to the determination. The operations of 1515 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1515 may be performed as described in reference to Figure 8 The voice call pause threshold manager 830 is used for execution.

[0157] At 1520, the method may include identifying a threshold for voice pauses for the packet-based voice call, the threshold being based on a number of voice call packets expected to be received during an active call state for the packet-based voice call during an evaluation period. The operations of 1520 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1520 may be performed as described in reference to Figure 8 The voice call pause threshold manager 830 may be used to perform the above-described voice call pause threshold manager 830. In some cases, the threshold is based on an assumed mixed speech pattern of the packet-based voice call.

[0158] At 1525, the method may include initiating a handover of the UE from the first wireless network entity to a different wireless network entity in response to a number of voice call packets received from the peer device during the evaluation period being below a threshold for a voice pause for a packet-based voice call. The operations of 1525 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1525 may be performed as described in reference to Figure 8 The handover manager 835 is used to perform the above operation.

[0159] The following provides an overview of various aspects of the disclosure:

[0160] Aspect 1: A method for wireless communication at a UE, comprising: establishing a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system; identifying a threshold for voice pauses for the packet-based voice call, the threshold being based at least in part on a number of voice call packets expected to be received during an active call state of the packet-based voice call during an evaluation period; and in response to the number of voice call packets received from the peer device during the evaluation period being lower than the threshold for voice pauses for the packet-based voice call, initiating a handover of the UE from the first wireless network entity to a different wireless network entity.

[0161] Aspect 2: The method according to Aspect 1 further includes: receiving from the peer device an indication of the number of packets sent from the peer device for the packet-based voice call, and wherein the handover of the UE is initiated at least in part based on a ratio of the number of voice call packets received from the peer device to the number of packets sent from the peer device during the evaluation period.

[0162] Aspect 3: The method of aspect 2, wherein the indication of the number of packets sent from the peer device is received in an RTCP transmitter report from the peer device.

[0163] Aspect 4: The method according to any one of Aspects 1 to 3 further includes: determining that the time elapsed since the report associated with the packet-based voice call was received exceeds a time threshold, and wherein the handover of the UE is initiating at least in part based on the number of voice call packets received from the peer device and the estimated number of voice call packets associated with the assumed mixed voice mode of the evaluation period.

[0164] Aspect 5: The method according to aspect 4, wherein the report associated with the packet-based voice call is an RTCP report.

[0165] Aspect 6: The method according to any one of aspects 1 to 5, wherein the threshold is based at least in part on a SID interval of the packet-based voice call, wherein a higher SID interval has a lower threshold and a lower SID interval has a higher threshold.

[0166] Aspect 7: The method according to any one of Aspects 1 to 6 further includes: estimating, for the evaluation period, a ratio of an expected number of packets sent from the peer device during the evaluation period to a maximum number of packets that can be sent during the evaluation period, and wherein the threshold is determined at least in part based on the estimated ratio.

[0167] Aspect 8: The method according to aspect 7, wherein a value of the ratio less than a silence threshold indicates that the peer device is silent, and the UE will refrain from triggering the handover during the evaluation period.

[0168] Aspect 9: The method according to any one of aspects 1 to 8, wherein the number of voice call packets received from the peer device during the evaluation period is based at least in part on voice call packets having an RTP timestamp within the evaluation period.

[0169] Aspect 10: A method according to any one of Aspects 1 to 9, wherein identifying the threshold of the voice pause and initiating the handover of the UE are performed as part of a voice call pause evaluation, and wherein the method further comprises: receiving at least one RTCP transmitter report indicating the number of RTP voice packets sent during the evaluation period; and initiating the voice call pause evaluation in response to the at least one RTCP transmitter report, wherein the threshold is based at least in part on the number of RTP voice packets indicated in the transmitter report and the number of SID frames within the evaluation period.

[0170] Aspect 11: A method according to any one of Aspects 1 to 10, wherein identifying the threshold of the voice pause and initiating the handover of the UE are performed as part of a voice call pause evaluation, and wherein the method further comprises: determining that a certain time period has passed since a previous evaluation period and no RTCP transmitter report has been received within the time period; and initiating the voice call pause evaluation in response to the determination, wherein the threshold is based at least in part on an assumed mixed voice mode of the packet-based voice call.

[0171] Aspect 12: The method according to any one of aspects 1 to 11, wherein the threshold for identifying the speech pause of the packet-based voice call is an adaptive threshold based on the amount of speech activity present during the evaluation period.

[0172] Aspect 13: The method according to any one of Aspects 1 to 12 also includes: receiving a handover message indicating the handover of the UE from the first wireless network entity to the second wireless network entity, wherein the second wireless network entity uses the same RAT as the first wireless network entity or a RAT different from the first wireless network entity.

[0173] Aspect 14: A method according to Aspect 13, wherein initiating the handover of the UE includes: modifying the criteria for sending a measurement report to the first wireless network entity that triggers the handover of the UE, wherein the measurement report is an inter-RAT measurement report or an intra-RAT measurement report based at least in part on measured channel conditions associated with wireless network entities of two or more RATs.

[0174] Aspect 15: An apparatus for performing wireless communications at a UE, comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method according to any one of Aspects 1 to 14.

[0175] Aspect 16: An apparatus for wireless communication at a UE, comprising at least one component for performing the method according to any one of aspects 1 to 14.

[0176] Aspect 17: A non-transitory computer-readable medium storing a code for wireless communication at a UE, the code comprising instructions executable by a processor to perform the method according to any one of aspects 1 to 14.

[0177] It should be noted that the methods described herein describe possible implementations, and that the various operations and steps may be rearranged or otherwise modified and that other implementations are possible. Furthermore, aspects from two or more methods may be combined.

[0178] Although aspects of LTE, LTE-A, LTE-A Pro, or NR systems may be described for example purposes, and LTE, LTE-A, LTE-A Pro, or NR terminology may be used in much of the description, the techniques described herein may also be applicable to networks other than LTE, LTE-A, LTE-A Pro, or NR networks. For example, the described techniques may be applicable to various other wireless communication systems, such as Ultra Mobile Broadband (UMB), Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, and other systems and radio technologies not explicitly mentioned herein.

[0179] The information and signals described herein may be represented using any of a variety of different techniques and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips mentioned throughout the specification may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0180] The various illustrative blocks and components described in conjunction with the disclosure herein may be implemented or performed using a general purpose processor, DSP, ASIC, CPU, FPGA or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in an alternative, the processor may be any processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0181] The functions described herein may be implemented using hardware, software executed by a processor, firmware, or any combination thereof. When implemented using software executed by a processor, the functions may be stored as one or more instructions or codes of a computer-readable medium or sent using one or more instructions or codes of a computer-readable medium. Other examples and specific implementations are within the scope of the present disclosure and the appended claims. For example, due to the nature of software, the functions described herein may be implemented using software executed by a processor, hardware, firmware, hard wiring, or a combination of any of these items. Features that implement the functions may also be physically located at different locations, including being distributed so that the various parts of the functions are implemented at different physical locations.

[0182] Computer-readable medium includes both non-transient computer storage medium and communication medium, and it includes any medium that facilitates computer program to be transmitted from one position to another position.Non-transient storage medium can be any available medium that can be accessed by general or special-purpose computer.By way of example and not limitation, non-transient computer-readable medium can include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disc (CD) ROM or other optical disc storage device, disk storage device or other magnetic storage device, or can be used for carrying or storing desired program code components and any other non-transient medium that can be accessed by general or special-purpose computer or general or special-purpose processor in the form of instruction or data structure.In addition, any connection is appropriately referred to as computer-readable medium.For example, if software is sent from website, server or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) or wireless technology such as infrared, radio and microwave, then coaxial cable, fiber optic cable, twisted pair, DSL or wireless technology such as infrared, radio and microwave are included in the definition of computer-readable medium. Disks and optical disks used herein include CDs, laser optical disks, optical optical disks, digital versatile disks (DVDs), floppy disks, and Blu-ray disks. Disks can reproduce data magnetically, and optical disks can reproduce data optically using lasers. Combinations of the above are also included within the scope of computer-readable media.

[0183] As used herein (including in the claims), "or" used in a list of items (e.g., a list of items followed by a phrase such as "at least one of" or "one or more of") indicates an inclusive list, so that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). In addition, as used herein, the phrase "based on" should not be interpreted as a reference to a closed set of conditions. For example, an example step described as "based on condition A" can be based on both condition A and condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase "based on" should be interpreted in the same manner as the phrase "based at least in part on."

[0184] The term "determining" encompasses a variety of actions, and thus, "determining" may include calculating, computing, processing, deriving, investigating, looking up (such as via looking up in a table, database or other data structure), ascertaining, and the like. Furthermore, "determining" may include receiving (e.g., receiving information), accessing (e.g., accessing data stored in a memory), etc. Additionally, "determining" may include parsing, obtaining, selecting, choosing, establishing, and other such similar actions.

[0185] In the drawings, similar components or features may have the same reference label. In addition, various components of the same type may be distinguished by following the reference label with a dash and a second label to distinguish between similar components. If only the first reference label is used in the specification, the description may apply to any of the similar components having the same first reference label, regardless of the second or other subsequent reference labels.

[0186] The descriptions set forth herein in conjunction with the accompanying drawings describe example configurations and do not represent all examples that may be implemented or within the scope of the claims. The term "example" as used herein means "used as an example, instance, or illustration," rather than "preferred" or "advantageous over other examples." The specific implementation includes specific details to provide an understanding of the described techniques. However, these techniques may be practiced without these specific details. In some cases, known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described examples.

[0187] The description herein is provided to enable one of ordinary skill in the art to implement or use the present disclosure. Various modifications to the present disclosure will be apparent to one of ordinary skill in the art, and the general principles defined herein may be applied to other variations without departing from the scope of the present disclosure. Thus, the present disclosure is not limited to the examples and designs described herein, but should be granted the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for wireless communication at a user equipment (UE), comprising: establishing a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system; identifying a threshold for voice pauses for the packet-based voice call, the threshold being based at least in part on a number of voice call packets expected to be received during an active call state for the packet-based voice call during an evaluation period; as well as In response to the number of voice call packets received from the peer device during the evaluation period being below the threshold for the voice pause for the packet-based voice call, initiating a handover of the UE from the first wireless network entity to a different wireless network entity.

2. The method according to claim 1, further comprising: receiving from the peer device an indication of a number of packets sent from the peer device for the packet-based voice call, and wherein initiating the handover of the UE is based at least in part on a ratio of the number of voice call packets received from the peer device to the number of packets sent from the peer device during the evaluation period.

3. The method of claim 2, wherein the indication of the number of packets sent from the peer device is received in a Real-time Transport Control Protocol (RTCP) transmitter report from the peer device.

4. The method according to claim 1, further comprising: determining that a time elapsed since receiving a report associated with the packet-based voice call exceeds a time threshold, and wherein initiating the handover of the UE is based at least in part on the number of voice call packets received from the peer device and an estimated number of voice call packets associated with an assumed mixed voice mode for the evaluation period.

5. The method of claim 4, wherein the report associated with the packet-based voice call is a Real-time Transport Control Protocol (RTCP) report.

6. The method of claim 1, wherein the threshold is based at least in part on a silence indicator (SID) interval of the packet-based voice call, wherein a higher SID interval has a lower threshold and a lower SID interval has a higher threshold.

7. The method according to claim 1, further comprising: A ratio of an expected number of packets sent from the peer device during the evaluation period to a maximum number of packets that can be sent during the evaluation period is estimated for the evaluation period, and wherein the threshold is determined based at least in part on the estimated ratio.

8. The method of claim 7, wherein a value of the ratio less than a silence threshold indicates that the peer device is silent and the UE will refrain from triggering the handover during the evaluation period.

9. The method of claim 1, wherein the number of voice call packets received from the peer device during the evaluation period is based at least in part on voice call packets having a real-time transport protocol (RTP) timestamp within the evaluation period.

10. The method of claim 1, wherein identifying the threshold of the voice pause and initiating the handover of the UE are performed as part of a voice call pause evaluation, and wherein the method further comprises: receiving at least one real-time transport control protocol (RTCP) transmitter report indicating a number of real-time transport protocol (RTP) voice packets sent during the evaluation period; as well as The voice call stall evaluation is initiated in response to the at least one RTCP transmitter report, wherein the threshold is based at least in part on the number of RTP voice packets indicated in the transmitter report and a number of silence indicator (SID) frames within the evaluation period.

11. The method of claim 1 , wherein identifying the threshold of the voice pause and initiating the handover of the UE are performed as part of a voice call pause evaluation, and wherein the method further comprises: determining that a certain period of time has elapsed since a previous evaluation period and no real-time transport control protocol (RTCP) transmitter reports have been received during the period of time; as well as The voice call pause evaluation is initiated in response to the determination, wherein the threshold is based at least in part on an assumed mixed voice pattern of the packet-based voice call.

12. The method of claim 1, wherein the threshold for identifying the speech pauses of the packet-based voice call is an adaptive threshold based on an amount of speech activity present during the evaluation period.

13. The method according to claim 1, further comprising: A handover message is received indicating a handover of the UE from the first wireless network entity to a second wireless network entity, wherein the second wireless network entity uses a same radio access technology (RAT) as the first wireless network entity or a different RAT than the first wireless network entity.

14. The method of claim 13, wherein initiating the handover of the UE comprises: Modifying criteria for sending a measurement report to the first wireless network entity that triggers handover of the UE, wherein the measurement report is an inter-RAT measurement report or an intra-RAT measurement report based at least in part on measured channel conditions associated with wireless network entities of two or more RATs.

15. An apparatus for wireless communication at a user equipment (UE), comprising: processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to: establishing a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system; identifying a threshold for voice pauses for the packet-based voice call, the threshold being based at least in part on a number of voice call packets expected to be received during an active call state for the packet-based voice call during an evaluation period; as well as In response to the number of voice call packets received from the peer device during the evaluation period being below the threshold for the voice pause for the packet-based voice call, initiating a handover of the UE from the first wireless network entity to a different wireless network entity.

16. The apparatus of claim 15, wherein the instructions are further executable by the processor to cause the apparatus to: receiving from the peer device an indication of a number of packets sent from the peer device for the packet-based voice call, and wherein the initiation of the handover of the UE is based at least in part on a ratio of the number of voice call packets received from the peer device to the number of packets sent from the peer device during the evaluation period.

17. The apparatus of claim 16, wherein the indication of the number of packets sent from the peer device is received in a Real-time Transport Control Protocol (RTCP) transmitter report from the peer device.

18. The apparatus of claim 15, wherein the instructions are further executable by the processor to cause the apparatus to: determining that a time elapsed since receiving a report associated with the packet-based voice call exceeds a time threshold, and wherein the initiation of the handover of the UE is based at least in part on the number of voice call packets received from the peer device and an estimated number of voice call packets associated with an assumed mixed voice mode for the evaluation period.

19. The apparatus of claim 18, wherein the report associated with the packet-based voice call is a Real-time Transport Control Protocol (RTCP) report.

20. The apparatus of claim 15, wherein the threshold is based at least in part on a silence indicator (SID) interval of the packet-based voice call, wherein a higher SID interval has a lower threshold and a lower SID interval has a higher threshold.

21. The apparatus of claim 15, wherein the instructions are further executable by the processor to cause the apparatus to: A ratio of an expected number of packets sent from the peer device during the evaluation period to a maximum number of packets that can be sent during the evaluation period is estimated for the evaluation period, and wherein the threshold is determined based at least in part on the estimated ratio.

22. The apparatus of claim 15, wherein the instructions for identifying the threshold of the voice pause and the instructions for initiating the handover of the UE are performed as part of a voice call pause evaluation, and wherein the instructions are further executable by the processor to cause the apparatus to: receiving at least one Real-time Transport Control Protocol (RTCP) transmitter report indicating a number of Real-time Transport Protocol (RTP) voice packets sent during the evaluation period; and The voice call stall evaluation is initiated in response to the at least one RTCP transmitter report, wherein the threshold is based at least in part on the number of RTP voice packets indicated in the transmitter report and a number of silence indicator (SID) frames within the evaluation period.

23. The apparatus of claim 15, wherein the instructions for identifying the threshold of the voice pause and the instructions for initiating the handover of the UE are performed as part of a voice call pause evaluation, and wherein the instructions are further executable by the processor to cause the apparatus to: determining that a certain period of time has elapsed since a previous evaluation period and no real-time transport control protocol (RTCP) transmitter reports have been received during the period of time; and The voice call pause evaluation is initiated in response to the determination, wherein the threshold is based at least in part on an assumed mixed voice pattern of the packet-based voice call.

24. The apparatus of claim 15, wherein the instructions are further executable by the processor to cause the apparatus to: A handover message is received indicating a handover of the UE from the first wireless network entity to a second wireless network entity, wherein the second wireless network entity uses a same radio access technology (RAT) as the first wireless network entity or a different RAT than the first wireless network entity.

25. An apparatus for wireless communication at a user equipment (UE), comprising: means for establishing a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system; means for identifying a threshold for voice pauses for the packet-based voice call, the threshold being based at least in part on a number of voice call packets expected to be received during an active call state of the packet-based voice call during an evaluation period; and Means for initiating handover of the UE from the first wireless network entity to a different wireless network entity in response to the number of voice call packets received from the peer device during the evaluation period being below the threshold for the voice pause of the packet-based voice call.

26. The apparatus according to claim 25, further comprising: means for receiving from the peer device an indication of a number of packets sent from the peer device for the packet-based voice call, and wherein initiation of the handover of the UE is based at least in part on a ratio of the number of voice call packets received from the peer device to the number of packets sent from the peer device during the evaluation period.

27. The apparatus of claim 25, wherein the identification of the threshold and the initiation of the handover of the UE are performed as part of a voice call stall evaluation, and wherein the apparatus further comprises: means for receiving at least one Real-time Transport Control Protocol (RTCP) transmitter report indicating a number of Real-time Transport Protocol (RTP) voice packets sent during the evaluation period; and means for initiating the voice call stall evaluation in response to the at least one RTCP transmitter report, wherein the threshold is based at least in part on the number of RTP voice packets indicated in the transmitter report and a number of silence indicator (SID) frames within the evaluation period.

28. A non-transitory computer-readable medium storing code for wireless communication at a user equipment (UE), the code comprising instructions executable by a processor to: establishing a packet-based voice call with a peer device via a first wireless network entity of a wireless communication system; identifying a threshold for voice pauses for the packet-based voice call, the threshold being based at least in part on a number of voice call packets expected to be received during an active call state for the packet-based voice call during an evaluation period; as well as In response to the number of voice call packets received from the peer device during the evaluation period being below the threshold for the voice pause for the packet-based voice call, initiating a handover of the UE from the first wireless network entity to a different wireless network entity.

29. The non-transitory computer readable medium of claim 28, wherein the instructions are further executable by the processor to: receiving from the peer device an indication of a number of packets sent from the peer device for the packet-based voice call, and wherein initiating the handover of the UE is based at least in part on a ratio of the number of voice call packets received from the peer device to the number of packets sent from the peer device during the evaluation period.

30. The non-transitory computer readable medium of claim 28, wherein the instructions are further executable by the processor to: determining that a time elapsed since receiving a report associated with the packet-based voice call exceeds a time threshold, and wherein initiating the handover of the UE is based at least in part on the number of voice call packets received from the peer device and an estimated number of voice call packets associated with an assumed mixed voice mode for the evaluation period.

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