CN117981263A - Performing carrier switching using fallback control information - Google Patents

Abstract

Methods, systems, and devices for wireless communication at a User Equipment (UE) are described. The UE may identify that carrier switching is enabled at the UE for a physical uplink control channel and may receive a control signal lacking an indication for carrier switching. The UE may monitor for downlink transmissions on a primary serving cell of a set of serving cells in a physical uplink control channel set. The UE may then select one of the set of serving cells to send feedback information for the downlink transmission, wherein the selection is based on enabling carrier switching at the UE while the control signal lacks an indication for carrier switching. The UE may send the feedback information for the downlink transmission to the network entity according to the selection.

Description

Performing carrier switching using fallback control information

Cross Reference to Related Applications

This patent application claims priority from U.S. patent application No. 17/855,864, entitled "use of fallback control information to perform carrier switching (PERFORMING CARRIER SWITCHING WITH FALLBACK CONTROL INFORMATION)" filed by HUANG et al at 2022, 7, 1, which claims the benefit of U.S. provisional patent application No. 63/250,852, entitled "use of fallback control information to perform carrier switching (PERFORMING CARRIER SWITCHING WITH FALLBACK CONTROL INFORMATION)" filed by HUANG et al at 2021, 9, 30, each of which is assigned to the assignee of the present application and each of which is expressly incorporated herein by reference.

Technical Field

The following relates to wireless communications at a User Equipment (UE), including performing carrier switching using fallback control information.

Background

Wireless communication systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be able to support communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple access systems include fourth generation (4G) systems, such as Long Term Evolution (LTE) systems, LTE-advanced (LTE-a) systems, or LTE-a Pro systems, and fifth generation (5G) systems, which may be referred to as new air interface (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 network entities or one or more network access nodes, each supporting communication for multiple communication devices, which may be otherwise referred to as User Equipment (UE). In some wireless communication systems, a network entity may configure a UE for sending feedback. For example, the network entity may configure the UE to send feedback to the network entity during the first duration. However, in some cases, there may not be enough available resources for sending feedback. Thus, in some examples, feedback transmission techniques may be defective.

Disclosure of Invention

The described technology relates to improved methods, systems, devices, and apparatuses supporting performing carrier switching using fallback control information. In general, the described techniques provide a User Equipment (UE) that enables physical uplink control channel carrier switching and feedback deferral in the absence of a carrier switch indication in a control signal (e.g., a field in the control signal). The techniques described herein provide for the transmission of feedback information for downlink transmissions. The UE may receive a control signal lacking an indication for carrier switching. In some examples, the UE may monitor a first time slot for downlink transmissions on a primary serving cell (e.g., component carrier) of a plurality of serving cells in a physical uplink control channel group. The UE may be configured to send feedback information for the downlink transmission in one of a set of serving cells. The UE may select a primary component carrier or a secondary component carrier for transmitting the feedback information based on identifying that carrier switching is enabled at the UE and receiving a control signal lacking an indication for carrier switching.

A method for wireless communication at a User Equipment (UE) is described. The method may include: identifying that carrier switching is enabled at the UE for a physical uplink control channel; selecting one of a set of multiple serving cells to send feedback information for downlink transmissions, wherein the selecting is based on enabling carrier switching at the UE and receiving a physical downlink control channel lacking an indication of how to perform the carrier switching; and sending the feedback information for the downlink transmission to the network entity according to the selection.

An apparatus for wireless communication is described. The apparatus may include: a processor; a memory coupled to the processor; and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to: identifying that carrier switching is enabled at the UE for the physical uplink control channel; selecting one of a set of multiple serving cells to send feedback information for downlink transmissions, wherein the selecting is based on enabling carrier switching at the UE and receiving a physical downlink control channel lacking an indication of how to perform the carrier switching; and sending the feedback information for the downlink transmission to the network entity according to the selection.

Another apparatus for wireless communication at a UE is described. The apparatus may include: means for identifying that carrier switching is enabled at the UE for a physical uplink control channel; means for selecting one of a set of multiple serving cells to send feedback information for a downlink transmission, wherein the selecting is based on enabling carrier switching at the UE and receiving a physical downlink control channel lacking an indication of how to perform the carrier switching; and means for sending the feedback information for the downlink transmission to the network entity in accordance with the selection.

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: identifying that carrier switching is enabled at the UE for a physical uplink control channel; selecting one of a set of multiple serving cells to send feedback information for downlink transmissions, wherein the selecting is based on enabling carrier switching at the UE and receiving a physical downlink control channel lacking an indication of how to perform the carrier switching; and sending the feedback information for the downlink transmission to the network entity according to the selection.

In some examples of the methods, apparatus, and non-transitory computer readable media described herein, selecting one of the plurality of serving cells may include operations, features, means, or instructions for: a primary serving cell of the UE is selected to transmit the feedback information for the downlink transmission.

Some examples of the methods, apparatus, and non-transitory computer readable media described herein may also include operations, features, means, or instructions for: identifying, for the primary serving cell, a scheduling conflict between downlink reception and uplink transmission of the feedback information; scanning remaining serving cells of the set of multiple serving cells for availability of uplink resources for transmitting the feedback information according to a predefined ordering associated with a carrier switch time pattern configured for the UE; and selecting the secondary serving cell based on the availability of the uplink resource on the secondary serving cell.

In some examples of the methods, apparatus, and non-transitory computer readable media described herein, selecting one of the plurality of serving cells may include operations, features, means, or instructions for: identifying that the radio resource control signal includes an indication of a carrier switch time pattern; and selecting a primary serving cell or a secondary serving cell to transmit the feedback information based on identifying the carrier switch time pattern.

In some examples of the methods, apparatus, and non-transitory computer readable media described herein, selecting one of the plurality of serving cells may include operations, features, means, or instructions for: identifying that the radio resource control configuration of the UE does not include a carrier switch time pattern; and selecting a primary serving cell of the UE to send the feedback information based on identifying that the radio resource control configuration does not include the carrier switch time pattern.

In some examples of the methods, apparatus, and non-transitory computer readable media described herein, selecting one of the plurality of serving cells may include operations, features, means, or instructions for: identifying that a radio resource control configuration of the UE includes a carrier switch time pattern; identifying that the physical downlink control channel may be received in a UE-specific search space; and selecting a secondary serving cell to send the feedback information based on identifying that the radio resource control configuration includes the carrier switch time pattern and that the physical downlink control channel is likely to be received in the UE-specific search space.

In some examples of the methods, apparatus, and non-transitory computer readable media described herein, selecting one of the plurality of serving cells may include operations, features, means, or instructions for: identifying that a radio resource control configuration of the UE includes a carrier switch time pattern; identifying that the physical downlink control channel may not be received in the UE-specific search space; and selecting a primary serving cell to transmit the feedback information based on identifying that the radio resource control configuration includes the carrier switch time pattern and that the physical downlink control channel is likely to be received in the UE-specific search space. In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the indication of how to perform the carrier switch includes Downlink Control Information (DCI) format 1_0 or 1_1 or 1_2.

A method for wireless communication at a network entity is described. The method may include: identifying that carrier switching is enabled at the UE for the physical uplink control channel; transmitting a physical downlink control channel to the UE that does not include an indication of how to perform the carrier switch; and receiving feedback information for a downlink transmission from the UE, wherein the feedback information is received on one of a set of multiple serving cells configured for the UE based on enabling carrier switching and the physical downlink control channel at the UE.

An apparatus for wireless communication is described. The apparatus may include: a processor; a memory coupled to the processor; and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to: identifying that carrier switching is enabled at the UE for the physical uplink control channel; transmitting a physical downlink control channel to the UE that does not include an indication of how to perform the carrier switch; and receiving feedback information for a downlink transmission from the UE, wherein the feedback information is received on one of a set of multiple serving cells configured for the UE based on enabling carrier switching and the physical downlink control channel at the UE.

Another apparatus for wireless communication at a network entity is described. The apparatus may include: means for identifying that carrier switching is enabled at the UE for the physical uplink control channel; means for transmitting to the UE a physical downlink control channel that does not include an indication of how to perform the carrier switch; and means for receiving feedback information for a downlink transmission from the UE, wherein the feedback information is received on one of a set of multiple serving cells configured for the UE based on enabling carrier switching and the physical downlink control channel at the UE.

A non-transitory computer-readable medium storing code for wireless communication at a network entity is described. The code may include instructions executable by a processor to: identifying that carrier switching is enabled at the UE for the physical uplink control channel; transmitting a physical downlink control channel to the UE that does not include an indication of how to perform the carrier switch; and receiving feedback information for a downlink transmission from the UE, wherein the feedback information is received on one of a set of multiple serving cells configured for the UE based on enabling carrier switching and the physical downlink control channel at the UE.

In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the feedback information may include operations, features, means, or instructions for: the feedback information is received on a primary serving cell of the set of multiple serving cells.

In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the feedback information may include operations, features, means, or instructions for: identifying that the radio resource control signal includes an indication of a carrier switch time pattern; and receiving the feedback information on the primary or secondary serving cell based on the indication identifying that the radio resource control signal includes the carrier switch time pattern.

In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the feedback information may include operations, features, means, or instructions for: identifying that the radio resource control signal does not include an indication of a carrier switch time pattern; and receiving the feedback information on the primary serving cell based on the indication identifying that the radio resource control signal does not include the carrier switch time pattern.

In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the feedback information may include operations, features, means, or instructions for: identifying that the radio resource control signal includes an indication of a carrier switch time pattern; identifying that the physical downlink control channel may be transmitted in a UE-specific search space; and receiving the feedback information on a secondary serving cell based on identifying that the radio resource control signal includes the indication of the carrier switch time pattern and that the physical downlink control channel may be transmitted in the UE-specific search space.

In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the feedback information may include operations, features, means, or instructions for: identifying that the radio resource control signal includes an indication of a carrier switch time pattern; identifying that the physical downlink control channel may not be transmitted in the UE-specific search space; and receiving the feedback information on a primary serving cell based on identifying that the radio resource control signal includes the indication of the carrier switch time pattern and that the physical downlink control channel may be transmitted in the UE-specific search space. In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the indication of how to perform the carrier switch includes DCI format 1_0 or 1_1 or 1_2.

Drawings

Fig. 1 illustrates an example of a wireless communication system supporting performing carrier switching using back-off control information according to examples as disclosed herein.

Fig. 2 illustrates an example of a wireless communication system supporting performing carrier switching using back-off control information in accordance with examples as disclosed herein.

Fig. 3 illustrates an example of a communication scheme supporting performing carrier switching using fallback control information according to examples as disclosed herein.

Fig. 4 illustrates an example of a process flow supporting performing carrier switching using fallback control information according to examples as disclosed herein.

Fig. 5 illustrates an example of a process flow supporting performing carrier switching using fallback control information according to examples as disclosed herein.

Fig. 6 and 7 illustrate block diagrams of devices supporting performing carrier switching using fallback control information according to examples as disclosed herein.

Fig. 8 illustrates a block diagram of a communication manager that supports performing carrier switching using fallback control information in accordance with an example as disclosed herein.

Fig. 9 illustrates a diagram of a system including a device that supports performing carrier switching using fallback control information according to an example as disclosed herein.

Fig. 10 and 11 illustrate block diagrams of devices supporting performing carrier switching using fallback control information according to examples as disclosed herein. Fig. 12 illustrates a block diagram of a communication manager that supports performing carrier switching using fallback control information in accordance with an example as disclosed herein.

Fig. 13 illustrates a diagram of a system including a device that supports performing carrier switching using fallback control information according to an example as disclosed herein.

Fig. 14-17 illustrate flowcharts of methods supporting performing carrier switching using fallback control information according to examples as disclosed herein.

Detailed Description

In a wireless communication system, a network entity may send downlink transmissions to a User Equipment (UE), and the UE may be configured with time and frequency resources for receiving the downlink transmissions. In some examples, the network entity may schedule transmissions via radio resource control signaling (e.g., during a radio resource control configuration period) and may periodically transmit downlink transmissions to the UE according to the radio resource control signaling. The network entity may configure the UE to transmit physical uplink control channel transmissions on a physical uplink control channel group comprising a primary serving cell and one or more secondary serving cells. For example, the network entity may configure the UE to send feedback information (e.g., hybrid automatic repeat request (HARQ) Acknowledgements (ACKs) or Negative Acknowledgement (NACK) feedback) for downlink transmissions. The UE may receive the downlink transmission and may send feedback on one or more uplink symbols using a physical uplink control channel. Transmitting physical uplink control channel transmissions on multiple serving cells (e.g., a primary serving cell and one or more serving cells) may also be referred to herein as physical uplink control channel carrier switching.

In some examples, the network entity may configure the UE to transmit feedback on a different component carrier instead of delaying the transmission of feedback to a subsequent time slot on the primary component carrier. For dynamic switching of carriers, a control signal (e.g., dynamic control information) may include a new field to indicate a target component carrier for sending feedback in response to a downlink transmission. However, in some cases, because the control signal lacks a carrier switch indication of the time slot (e.g., a field in the control signal), the UE may receive the control signal and may not be able to identify the time slot for transmitting the feedback. Instead, the UE may delay the transmission of the feedback to a subsequent time slot in the primary component carrier, which may increase the delay of the feedback report.

To reduce feedback reporting latency, the network entity may configure the UE to send feedback according to different techniques. For the first technique, the UE may determine that a control signal scheduling a downlink transmission lacks an indication (e.g., a field in the control signal) for carrier switching. In such cases, the UE may send feedback on the primary component carrier. For the second technique, the UE may determine that the radio resource control includes a carrier switch time mode. In such cases, the UE may use the secondary component carrier to send feedback according to the carrier switch time pattern. If the UE determines that the radio resource control lacks a carrier switch time mode, the UE may use a primary component carrier to send feedback. For the third technique, the UE may determine that the radio resource control includes a carrier switch time mode and receive a control signal in a UE-specific carrier space. In this case, the UE may use the secondary component carrier to transmit feedback. On the other hand, if the UE determines that the radio resource control includes a carrier switch time pattern and that the control signal is not received in the UE-specific carrier space, the UE may use the primary component carrier to transmit feedback.

The UE supports techniques for performing carrier switching using back-off control information described herein, which may utilize the techniques described herein to achieve power savings and extend battery life while ensuring reliable and efficient communications. Certain aspects of the subject matter described in this disclosure can be implemented to support high reliability and low latency communications, as well as other examples. The described techniques may thus include features for improving power consumption, spectral efficiency, higher data rates, and in some examples may promote efficiency for high reliability and low latency operations, among other benefits.

Aspects of the present disclosure are first described in the context of a wireless communication system. Aspects of the present disclosure are further illustrated and described with reference to communication schemes and process flows. Aspects of the present disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts relating to performing carrier switching using fallback control information.

Fig. 1 illustrates an example of a wireless communication system 100 supporting performing carrier switching using back-off control information according to examples as disclosed herein. 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 LTE-advanced (LTE-a) network, an LTE-a Pro network, or a new air interface (NR) network. In some examples, the wireless communication system 100 may support enhanced broadband communications, ultra-reliable communications, low latency communications, or communications with low cost and low complexity devices, or any combination thereof.

The network entities 105 may be dispersed throughout a geographic region to form the wireless communication system 100 and may be devices in different forms or with different capabilities. The network entity 105 and the UE 115 may communicate wirelessly via one or more communication links 125. Each network entity 105 may provide a coverage area 110 over which the ue 115 and the network entity 105 may establish one or more communication links 125. Coverage area 110 may be an example of a geographic area over which network entity 105 and UE 115 may support signal communications in accordance with one or more radio access technologies.

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 UE 115 may be a different form of device or a device with different capabilities. Some example UEs 115 are illustrated in fig. 1. As shown in fig. 1, the UEs 115 described herein may be capable of communicating with various types of devices, such as other UEs 115, network entities 105, or network equipment (e.g., core network nodes, relay devices, integrated Access and Backhaul (IAB) nodes, or other network equipment).

The network entities 105 may communicate with the core network 130 or with each other or both. For example, the network entity 105 may interact with the core network 130 through one or more backhaul links 120 (e.g., via S1, N2, N3, or other interfaces). The network entities 105 may communicate with each other directly (e.g., directly between the network entities 105) or indirectly (e.g., via the core network 130) or both through the backhaul link 120 (e.g., via X2, xn, or other interface). In some examples, the backhaul link 120 may be or include one or more wireless links.

One or more of the network entities 105 described herein may include or may be referred to by those of ordinary skill in the art as a transceiver base station, a radio network entity, 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 home node B, a home evolved node B, or other suitable terminology.

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 terminology, where "device" may also be referred to as a unit, station, terminal, client, or the like. The UE 115 may also include or be referred to as a personal electronic device, such as a cellular telephone, a Personal Digital Assistant (PDA), a tablet computer, a laptop computer, or a personal computer. In some examples, the 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.

The UEs 115 described herein may be capable of communicating with various types of devices, such as other UEs 115 that 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 network entities, and so forth, as shown in fig. 1.

The UE 115 and the network entity 105 may wirelessly communicate with each other via one or more communication links 125 on one or more carriers. The term "carrier" may refer to a set of radio frequency spectrum resources having a defined physical layer structure for supporting the communication link 125. For example, the carrier for the communication link 125 may include a portion (e.g., a bandwidth portion (BWP)) of a radio frequency spectrum band operating in accordance with one or more physical layer channels of a given radio access technology (e.g., LTE-A, LTE-APro, NR). Each physical layer channel may carry acquisition signaling (e.g., synchronization signals, system information), control signaling to coordinate carrier operation, user data, or other signaling. The wireless communication system 100 may support communication with UEs 115 using carrier aggregation or multi-carrier operation. According to a carrier aggregation configuration, the UE 115 may be configured with a plurality of 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.

In some examples (e.g., in a carrier aggregation configuration), a carrier may also have acquisition signaling or control signaling that coordinates the operation of other carriers. The carrier may be associated with a frequency channel, such as an evolved universal mobile telecommunications system terrestrial radio access (E-UTRA) absolute radio frequency channel number (EARFCN), and may be positioned according to a channel raster for discovery by the UE 115. The carrier may operate in an independent mode in which initial acquisition and connection may be made by the UE 115 via the carrier, or in a non-independent mode in which a connection is anchored using different carriers (e.g., of the same or different radio access technologies).

The communication link 125 shown in the wireless communication system 100 may include an uplink transmission from the UE 115 to the network entity 105 or a downlink transmission from the network entity 105 to the UE 115. The carrier may carry downlink communications or uplink communications (e.g., in FDD mode), or may be configured to carry downlink communications with uplink communications (e.g., in TDD mode).

The carrier may be associated with a particular bandwidth of the radio frequency spectrum, and in some examples, the carrier bandwidth may be referred to as the "system bandwidth" of the carrier or wireless communication system 100. For example, the carrier bandwidth may be one of a plurality of determined bandwidths of a carrier for a particular radio access technology (e.g., 1.4 megahertz (MHz), 3MHz, 5MHz, 10MHz, 15MHz, 20MHz, 40MHz, or 80 MHz). Devices of the wireless communication system 100 (e.g., the network entity 105, the UE 115, or both) may have a hardware configuration that supports communication over a particular carrier bandwidth or may be configurable to support communication over one of a set of carrier bandwidths. In some examples, wireless communication system 100 may include a network entity 105 or UE 115 that supports simultaneous communication via carriers associated with multiple carrier bandwidths. In some examples, each served UE 115 may be configured to operate over part (e.g., sub-band, BWP) or all of the carrier bandwidth.

The signal waveform transmitted on the carrier may include a plurality of subcarriers (e.g., using a multi-carrier modulation (MCM) technique such as Orthogonal Frequency Division Multiplexing (OFDM) or discrete fourier transform spread OFDM (DFT-S-OFDM)). In a system employing MCM techniques, a resource element may include one symbol period (e.g., the duration of one modulation symbol) and one subcarrier, where the symbol period and subcarrier spacing are 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). Thus, the more resource elements that the UE 115 receives, and the higher the order of the modulation scheme, the higher the data rate for the UE 115 may be. The wireless communication resources may refer to a combination of radio frequency spectrum resources, time resources, and spatial resources (e.g., spatial layers or beams), and the use of multiple spatial layers may further improve the data rate or data integrity of the communication with the UE 115.

The time interval for the network entity 105 or UE 115 may be expressed in multiples of a basic time unit, which may refer to, for example, a sampling period of T _s＝1/(Δf_max·N_f) seconds, where Δf _max may represent the maximum supported subcarrier spacing and N _f may represent the maximum supported Discrete Fourier Transform (DFT) size. 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).

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

A subframe, slot, mini-slot, or symbol may be a minimum 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 shortened TTI (sTTI)).

The physical channels may be multiplexed on the carrier according to various techniques. For example, the physical control channels and physical data channels may be multiplexed on the downlink carrier using one or more of Time Division Multiplexing (TDM), frequency Division Multiplexing (FDM), or hybrid TDM-FDM techniques. The control region (e.g., control resource set (CORESET)) of the physical control channel may be defined by a number of symbol periods and may extend across the system bandwidth or a subset of the system bandwidth of the carrier. One or more control regions (e.g., CORESET) may be configured for a group of UEs 115. For example, one or more of UEs 115 may monitor or search the control region for control information based on one or more sets of search spaces, and each set of search spaces may include one or more control channel candidates in one or more aggregation levels arranged in a cascaded manner. The aggregation level of control channel candidates may refer to the number of control channel resources (e.g., control Channel Elements (CCEs)) associated with coding information for a control information format having a given payload size. The set of search spaces may include a common set of search spaces configured to transmit control information to a plurality of UEs 115, and a UE-specific set of search spaces configured to transmit control information to a specific UE 115.

Each 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 for communicating with the network entity 105 (e.g., on a carrier) and may be associated with an identifier (e.g., a Physical Cell Identifier (PCID), a Virtual Cell Identifier (VCID), or others) for distinguishing between neighboring cells. In some examples, a cell may also refer to a geographic coverage area 110 or a portion (e.g., a sector) of geographic coverage area 110 over which a logical communication entity operates. Such cells may range from smaller areas (e.g., structures, subsets of structures) to larger areas, depending on various factors such as the capabilities of the network entity 105. For example, a cell may be or include a building, a subset of buildings, or an outside space between or overlapping geographic coverage areas 110, and so forth.

A macrocell generally covers a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs 115 with service subscription with network providers supporting the macrocell. The small cell may be associated with a lower power network entity 105 than the macro cell, and may operate in the same or different (e.g., licensed, unlicensed) frequency band as the macro cell. The small cell may provide unrestricted access to UEs 115 with a subscription to the service of the network provider, or may provide restricted access to UEs 115 associated with the small cell (e.g., UEs 115 in a Closed Subscriber Group (CSG), UEs 115 associated with users in a home or office). The network entity 105 may support one or more cells and may also use one or more component carriers to support communications on the one or more cells.

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 for different types of devices.

In some examples, the network entity 105 may be mobile and thus provide communication coverage to the mobile geographic coverage area 110. In some examples, different geographic coverage areas 110 associated with different technologies may be supported by the same network entity 105, although the different geographic coverage areas 110 may overlap. In other examples, overlapping geographic 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 geographic coverage areas 110 using the same or different radio access technologies.

Some UEs 115 may be configured to employ a reduced power consumption mode of operation, such as half-duplex communication (e.g., a mode that supports unidirectional communication via transmission or reception but does not support simultaneous transmission and reception). In some examples, half-duplex communications may be performed at a reduced peak rate. Other power saving techniques for UE 115 include: enter a power-saving deep sleep mode when not engaged in active communication, operate over a limited bandwidth (e.g., according to narrowband communication), or a combination of these techniques. For example, some UEs 115 may be configured to operate using a narrowband protocol type that is associated with a defined portion or range (e.g., a set of subcarriers or Resource Blocks (RBs)) within a carrier, within a guard band of a carrier, or outside of a carrier.

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 communications (URLLC). The UE 115 may be designed to support ultra-reliable, low latency, or critical functions. Ultra-reliable communications may include private communications or group communications, 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 are used interchangeably herein.

In some examples, the UE 115 may also be capable of communicating directly with other UEs 115 over a device-to-device (D2D) communication link 135 (e.g., using peer-to-peer (P2P) or D2D protocols). One or more UEs 115 utilizing D2D communication may be located within the geographic coverage area 110 of the network entity 105. Other UEs 115 in the group may be outside of the geographic coverage area 110 of the network entity 105 or otherwise unable to receive transmissions from the network entity 105. In some examples, a group of UEs 115 communicating via D2D communication may utilize a one-to-many (1:M) system in which each UE 115 transmits to each other UE 115 in the group. In some examples, the network entity 105 facilitates scheduling resources for D2D communications. In other cases, D2D communication is performed between these UEs 115 without the involvement of the network entity 105.

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 (5 GC), which may include at least one control plane entity (e.g., a Mobility Management Entity (MME), an access and mobility management function (AMF)) that manages 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)) that routes packets or interconnects to external networks. The control plane entity may manage non-access stratum (NAS) functions such as mobility, authentication, and bearer management for UEs 115 served by the network entity 105 associated with the core network 130. User IP packets may be communicated through a user plane entity that may provide IP address assignment, as well as other functions. The user plane entity may be connected to IP services 150 for one or more network operators. IP services 150 may include access to the internet, one or more intranets, an IP Multimedia Subsystem (IMS), or a packet switched streaming service.

Some network devices, such as network entity 105, may include subcomponents, such as access network entity 140, which may be an example of an Access Node Controller (ANC). Each access network entity 140 may communicate with UEs 115 through one or more other access network transmitting entities 145, which may be referred to as radio heads, intelligent radio heads, or transmission/reception points (TRPs). Each access network transmitting entity 145 may include one or more antenna panels. In some configurations, the various functions of each access network entity 140 or network entity 105 may be distributed across various network devices (e.g., radio heads and ANCs) or incorporated into a single network device (e.g., network entity 105).

The wireless communication system 100 may operate using one or more frequency bands, typically in the range of 300 megahertz (MHz) to 300 gigahertz (GHz). Generally, the region from 300MHz to 3GHz is referred to as the Ultra High Frequency (UHF) region or decimeter range because the wavelength range is about one decimeter to one meter. Although UHF waves may be blocked or redirected by building and environmental features, these waves may be sufficiently transparent to the structure for the macro cell to provide service to UEs 115 located indoors. Transmission of UHF waves may be associated with smaller antennas and shorter ranges (e.g., less than 100 km) than transmission of smaller frequencies and longer wavelengths using the High Frequency (HF) or Very High Frequency (VHF) portions of the spectrum below 300 MHz.

The wireless communication system 100 may utilize both the licensed radio frequency spectrum band and the unlicensed radio frequency spectrum band. For example, the wireless communication system 100 may employ Licensed Assisted Access (LAA), LTE unlicensed (LTE-U) radio access technology, or NR technology in unlicensed frequency bands, such as the 5GHz industrial, scientific, and medical (ISM) frequency bands. Devices such as network entity 105 and UE 115 may employ carrier sensing for collision detection and avoidance when operating in the unlicensed radio frequency spectrum band. In some examples, operation in the unlicensed frequency band may be based on a carrier aggregation configuration (e.g., LAA) in conjunction with component carriers operating in the licensed frequency band. Operations in the unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, among others.

The network entity 105 or UE 115 may be equipped with multiple antennas that may be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communication, or beamforming. The antennas of network entity 105 or UE 115 may be located within one or more antenna arrays or antenna panels, which may support MIMO operation or transmit or receive beamforming. For example, one or more network entity 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 network entity 105 may be located at different geographic locations. The network entity 105 may have an antenna array with a plurality of rows and columns of antenna ports that the network entity 105 may use to support beamforming for communication with the UE 115. Also, UE 115 may have one or more antenna arrays that may support various MIMO or beamforming operations. Additionally or alternatively, the antenna panel may support radio frequency beamforming for signals transmitted via the antenna ports.

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., network entity 105, UE 115) to shape or steer antenna beams (e.g., transmit beams, receive beams) along a spatial path between the transmitting device and the receiving device. Beamforming may be achieved by: signals transmitted via antenna elements of the antenna array are combined such that some signals propagating in a particular direction relative to the antenna array experience constructive interference, while other signals experience destructive interference. The adjusting of the signal transmitted via the antenna element may include: the transmitting device or the receiving device applies an amplitude offset, a phase offset, or both to the signal carried via the antenna element associated with the device. The adjustment associated with each of these antenna elements may be defined by a set of beamforming weights associated with a particular orientation (e.g., with respect to an antenna array of the transmitting device or the receiving device or with respect to some other orientation).

The network entity 105 or UE 115 may use beam sweep techniques as part of the beam forming operation. For example, network entity 105 may perform beamforming operations for directional communications with UE 115 using multiple antennas or antenna arrays (e.g., antenna panels). Some signals (e.g., synchronization signals, reference signals, beam selection signals, or other control signals) may be transmitted multiple times by the network entity 105 in different directions. For example, the network entity 105 may transmit signals according to different sets of beamforming weights associated with different transmit directions. The beam directions may be identified (e.g., by a transmitting device (such as network entity 105) or by a receiving device (such as UE 115)) using transmissions in different beam directions for later transmission or reception by network entity 105.

Some signals, such as data signals associated with a particular receiving device, may be transmitted by network entity 105 in a single beam direction (e.g., a direction associated with a receiving device, such as UE 115). In some examples, the beam direction associated with transmission in a single beam direction may be determined based on signals that have been transmitted in one or more beam directions. For example, UE 115 may receive one or more of the signals transmitted by network entity 105 in different directions and may report an indication to network entity 105 that UE 115 received the signal with the highest signal quality or other acceptable signal quality.

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 Packet Data Convergence Protocol (PDCP) layer may be IP-based. The Radio Link Control (RLC) layer may perform packet segmentation and reassembly to communicate over logical channels. The Medium Access Control (MAC) layer may perform priority handling and multiplexing of logical channels to transport channels. The MAC layer may also use error detection techniques, error correction techniques, or both to support retransmissions at the MAC layer to improve link efficiency. In the control plane, the radio resource control protocol layer may provide for the establishment, configuration and maintenance of radio resource control connections between the UE 115 and the network entity 105 or the core network 130 supporting radio bearers for user plane data. At the physical layer, transport channels may be mapped to physical channels.

The UE 115 and the network entity 105 may support retransmission of data to increase the likelihood that the data is successfully received. HARQ feedback is a technique for increasing the likelihood that data is properly received over the communication link 125. HARQ may include a combination of error detection (e.g., using Cyclic Redundancy Check (CRC)), forward Error Correction (FEC), and retransmission (e.g., automatic repeat request (ARQ)). HARQ may improve throughput at the MAC layer under poor radio conditions (e.g., low signal-to-noise conditions). In some examples, a device may support a simultaneous slot HARQ feedback in which the device may provide HARQ feedback in one particular time slot for data received in a previous symbol in the time slot. In other cases, the device may provide HARQ feedback in a subsequent time slot or according to some other time interval.

In accordance with one or more aspects described herein, the UE 115 may identify that carrier switching is enabled at the UE 115 for a physical uplink control channel and may receive a control signal lacking an indication (e.g., a field in the control signal) for carrier switching. The UE 115 may monitor for downlink transmissions on a primary serving cell of a set of serving cells in a physical uplink control channel set. The UE 115 may then select one of the set of serving cells to send feedback information for the downlink transmission, where the selection is based on enabling carrier switching at the UE while the control signal lacks an indication for carrier switching. After selecting the serving cell, the UE 115 may send feedback information for the downlink transmission to the network entity 105. In some examples, UE 115 may identify whether the radio resource control signal includes an indication of a carrier switch time mode. The UE 115 may select a secondary serving cell to send feedback information based on identifying that the radio resource control signal includes an indication of a carrier switch time pattern. Alternatively, the UE 115 may select a primary serving cell to send the feedback information based on an indication identifying that the radio resource control signal does not include a carrier switch time pattern.

Fig. 2 illustrates an example of a wireless communication system 200 that supports performing carrier switching using back-off control information in accordance with examples as disclosed herein. The wireless communication system 200 may implement or be implemented by aspects of the wireless communication system 100. For example, wireless communication system 200 may include UE 115-a and network entity 105-a, which may be examples of corresponding devices described with reference to fig. 1. The UE 115-a and the network entity 105-a may communicate over a communication link 220-a (e.g., downlink) and a communication link 220-b (e.g., uplink), which may be examples of the communication link 125 described with reference to fig. 1. The UE 115-a and the network entity 105-a may communicate within a geographic coverage area 110-a of the network entity 105-a, which may be an example of the geographic coverage area 110 described with reference to fig. 1. In wireless communication system 200, UE 115-a may use physical uplink control channel carrier switching and feedback deferral techniques to send feedback information 215 to network entity 105-a.

In some examples, UE 115-a may receive the downlink transmission and may send feedback on one or more uplink symbols after receiving the downlink transmission. For example, if the network entity 105-a sends a downlink transmission to the UE 115-a in a first time slot, the network entity 105-a may configure the UE 115-a to send feedback information for the transmission in a target time slot subsequent to the first time slot. In some cases, the network entity 105-a may send a transmission to the UE 115-a on a primary serving cell (e.g., primary component carrier), and the UE 115-a may be configured to send feedback information to the network entity 105-a.

However, in some cases, the TDD configuration may prevent the UE 115-a from sending feedback information to the network entity 105-a in the target time slot. For example, if the target time slot is designated as a downlink time slot, the UE 115-a may not be able to transmit feedback information in the target time slot. In other words, there may not be enough available uplink resources in the target slot for the UE to send feedback information. In such cases, UE 115-a may defer (e.g., delay) the transmission of the feedback information to a subsequent second time slot. Deferring the sending of feedback information may increase the latency associated with reporting feedback information to a network entity.

To reduce the feedback delay, the UE 115-a may send the feedback information based on attempting to delay the sending of the feedback information to a different serving cell before delaying the sending of the feedback information to a subsequent second time slot on the primary serving cell. For example, if there are not enough uplink resources available in the primary serving cell for the UE to send feedback information (e.g., if the UE identifies a scheduling conflict associated with a target time slot on the primary serving cell), but there are enough uplink resources available on the secondary serving cell for sending feedback information, the UE may send feedback information on the secondary serving cell. Thus, the UE may avoid incurring additional delay associated with delaying the transmission of feedback information to a subsequent second time slot.

In some examples, the UE may select a secondary serving cell from a physical uplink control channel group including a primary serving cell (e.g., primary component carrier) and one or more secondary serving cells (e.g., secondary component carriers). Additionally or alternatively, the UE may select one of the serving cells based on a time pattern associated with the physical uplink control channel group. In TDD configuration uplink carrier aggregation (where all component carriers in a physical uplink control channel group are TDD configuration carriers), the network entity 105-a may configure the TDD configuration mode in an interleaved or complementary manner. The UE 115-a and the network entity 105-a may support two carrier switching modes: semi-static switching mode and dynamic switching mode. For semi-static handover mode, the UE 115-a may send feedback without a control indication. In such cases, the network entity 105-a may indicate the component carrier switch time mode via a radio resource control configuration. For dynamic switching mode, the UE 115-a may send feedback with control indication. In such cases, the control indication may include a field (e.g., a cell field indicator) that indicates the component carrier switch time mode. However, in some cases, the control signal may lack a carrier switch indication. In such cases, the UE 115-a may receive the control signal and may not be able to identify the time slot for transmitting the feedback. In contrast, UE 115-a may delay the transmission of the feedback to a subsequent time slot in the primary component carrier, which may increase the delay of the feedback report.

Aspects of the present disclosure provide techniques for selecting one of these secondary cells to send feedback when a control signal (e.g., DCI format 1_0 or 1_1 or 1_2) lacks a carrier switch indication (e.g., a field in the control signal). In wireless communication system 200, network entity 105-a may send control signaling 205 to UE 115-a. The control signaling 205 may include radio resource control signaling, dynamic signaling (e.g., downlink control information, MAC control element CE, or both). The Physical Downlink Control Channel (PDCCH) may carry dynamic signaling (e.g., downlink control information). In some examples, carrier switching may be enabled at UE 115-a for a physical uplink control channel. The control signaling 205 may schedule a downlink transmission 210 from the network entity 105-a to the UE 115-a in a first time slot. In some cases, the control signaling 205 may lack an indication for carrier switching. UE 115-a may receive downlink transmission 210 on a primary component carrier. In some cases, UE 115-a may not be able to send feedback information 215 in the primary component carrier. For example, there may be a scheduling conflict with the target slot that prevents the UE 115-a from transmitting feedback information 215 in the primary component carrier.

According to examples as disclosed herein, UE 115-a may use one or more feedback deferral techniques to transmit feedback information 215 in a time slot with available uplink resources. The UE 115-a may select one of a set of serving cells (including a primary component carrier and one or more secondary component carriers) to send feedback information for the downlink transmission. In some examples, the selection may be based on enabling carrier switching at the UE 115-a while the control signal lacks an indication (e.g., field) for carrier switching. In some examples, UE 115-a may determine whether the radio resource control signal includes an indication of a carrier switch time mode.

UE 115-a may select a primary component carrier to send feedback information 215 based on an indication identifying that the radio resource control signal does not include a carrier switch time pattern. Alternatively, the UE 115-a may select the secondary component carrier to send the feedback information 215 based on an indication identifying that the radio resource control signal includes a carrier switch time pattern. In some examples, if the radio resource control signal includes an indication of a carrier switch time mode, the UE 115-a may further determine whether the control signal is received in a UE-specific search space. The UE 115-a may select a secondary component carrier to send feedback information based on identifying that the radio resource control signal includes an indication of a carrier switch time pattern and receiving the control signal in a UE-specific search space. Alternatively, the UE 115-a may select a primary component carrier to send feedback information based on identifying that the radio resource control signal includes an indication of a carrier switch time pattern and receiving the control signal in a UE-specific search space.

The use of carrier switching and feedback deferral techniques for control signals lacking an indication for carrier switching may enable UE 115-a to send feedback information 215 to network entity 105-a with the benefits of reduced latency and increased efficiency, among other benefits. For example, the described techniques may enable a UE 115-a to transmit feedback information 215 in a target time slot on a different serving cell, rather than delaying the transmission of feedback information 215 to a subsequent second time slot on the same serving cell.

Fig. 3 illustrates an example of a communication scheme 300 supporting performing carrier switching using fallback control information according to examples as disclosed herein. Communication scheme 300 may implement or be implemented by aspects of wireless communication system 100 or wireless communication system 200. For example, the communication scheme 300 may be implemented by the UE 115 or the network entity 105 (which may be examples of corresponding devices described with reference to fig. 1 and 2). In communication scheme 300, UE 115 may defer transmission of feedback information 310 from slot 325-b to slot 325-c based on time pattern 330 and the TDD configuration of primary serving cell 315-a.

In the example of fig. 3, the network entity 105 may send a downlink transmission 305 to the UE 115. The network entity 105 may schedule downlink transmissions 305 via control signaling (which may include radio resource control signaling, downlink control information, and MAC control elements). In some cases, the PDCCH may carry control signaling. In some examples, the control signaling may also configure the UE 115 to send feedback information 310 for the downlink transmission 305. For example, the control signaling may indicate at least one of a timing offset 335 between the reception of the downlink transmission 305 and the transmission of the feedback information 310. In some examples, the UE 115 may be configured with a time pattern 330 associated with the physical uplink control channel group 320, a TDD configuration of each serving cell 315 in the physical uplink control channel group 320, or a combination thereof. The timing offset 335 may indicate a number of time slots between the time slot 325-a in which the network entity 105 sent the downlink transmission 305 and the time slot 325-b in which the UE 115 was scheduled to send the feedback information 310.

The time pattern 330 may indicate a target serving cell 315 (e.g., from the physical uplink control channel group 320) for each of the time slots 325. For example, the time pattern may indicate that secondary serving cell 315-b (e.g., secondary Component Carrier (SCC) -1) is the target serving cell 315 for timeslots 325-a, 325-e and 325-h, that secondary serving cell 315-c (e.g., SCC-2) is the target serving cell 315 for timeslots 325-b and 325-f, and that primary serving cell 315-a (e.g., primary Component Carrier (PCC)) is the target serving cell 315 for timeslots 325-c, 325-d and 325-g. Although three serving cells 315 in the physical uplink control channel group 320 are illustrated, it should be understood that the physical uplink control channel group 320 may include any number of serving cells 315. Likewise, it should be appreciated that the temporal pattern 330 may include any number of target serving cells 315 arranged in any order.

The TDD configuration of the serving cell 315 may indicate a slot type for each of the slots 325. For example, the TDD configuration of the primary serving cell 315-a can indicate that the slot 325-a is a downlink slot (e.g., a slot with downlink resources), the slot 325-c is a special slot (e.g., a slot with uplink resources and downlink resources), and the slot 325-d is an uplink slot (e.g., a slot with uplink resources). Although a particular combination of uplink, downlink, and special slots is illustrated, it should be appreciated that the TDD configuration associated with the serving cell 315 may include any number of different slot types arranged in any combination.

In some cases, if the network entity 105 configures the UE 115 to transmit feedback information 310 in slot 325-b on the primary serving cell 315-a, but the TDD configuration associated with the primary serving cell 315-a indicates that slot 325-b is a downlink slot, the UE 115 may not be able to transmit feedback information 310 in slot 325-b. In other words, there may not be sufficient uplink resources available on the primary serving cell 315-a in the slot 325-b for transmitting the feedback information 310. In such cases, UE 115 may delay the transmission of feedback information 310 to a different time slot 325. For example, UE 115 may defer transmission of feedback information 310 to slot 325-c because slot 325-c has sufficient uplink resources on primary serving cell 315-a to transmit feedback information 310. Deferring the transmission of feedback information 310 to time slots 325-c as shown in fig. 3 may increase the latency associated with reporting feedback information 310 to network entity 105.

According to the described techniques, UE 115 may send feedback information 310 with reduced latency and greater efficiency based on using physical uplink control channel carrier switching in combination with feedback deferral techniques (as described with reference to fig. 1 and 2). If carrier switching is enabled at UE 115, UE 115 may defer feedback transmission. In some examples, the control signal scheduling the downlink transmission may not include an indication for carrier switching. In such cases, based on one or more techniques, UE 115 may send feedback on primary serving cell 315-a or on one of secondary serving cells 315-b and 315-c. In some examples, UE 115 may select primary serving cell 315-a to send feedback information 310 based on an indication identifying that the radio resource control signal does not include a carrier switch time pattern. Alternatively, the UE 115 may select the secondary serving cell 315-b or 315-c to send the feedback information 310 based on an indication identifying that the radio resource control signal includes a carrier switch time pattern.

In some examples, if the radio resource control signal includes an indication of a carrier switch time mode, the UE 115 may further determine whether the control signal is received in a UE-specific search space. The UE 115 may select the primary serving cell 315-a or the secondary serving cell 315-b or 315-c to send feedback information based on identifying that the radio resource control signal includes an indication of a carrier switch time pattern and determining whether the control signal is received in a UE-specific search space. In some examples, if both secondary serving cell 315-b and secondary serving cell 315-c do not have sufficient available uplink resources in slot 325-b for transmitting feedback information 310, UE 115 may trigger a feedback deferral of feedback information 310 to slot 325-c and may perform another physical uplink control channel carrier switching procedure to determine if serving cell 315 has sufficient available uplink resources in slot 325-c for transmitting feedback information 310 in physical uplink control channel group 320.

For example, if UE 115 determines that there are not enough available uplink resources in slot 325-b for transmitting feedback information 310 on primary serving cell 315-a (e.g., target serving cell 315 for slot 325-c, as indicated in time pattern 330), UE 115 may scan for other serving cells (e.g., secondary serving cell 315-b and secondary serving cell 315-c) in physical uplink control channel group 320 before deferring transmission of feedback information 310 to slot 325-c. If UE 115 determines that there are sufficient uplink resources available for transmitting feedback information 310 in slot 325-b (e.g., a target slot for feedback information 310, as indicated by timing offset 335) on secondary serving cell 315-b or secondary serving cell 315-c, UE 115 may delay the transmission of feedback information 310 to secondary serving cell 315-b or secondary serving cell 315-c (e.g., based on a preconfigured ordering for serving cell 315). That is, rather than delaying the transmission of feedback information 310 to slot 325-c, UE 115 may transmit feedback information 310 in slot 325-b on a different serving cell 315. Thus, among other benefits, UE 115 may transmit feedback information 310 with reduced latency.

Fig. 4 illustrates an example of a process flow 400 supporting performing carrier switching using fallback control information in accordance with examples as disclosed herein. The process flow 400 may be implemented by one or more wireless devices (such as UEs), which may be examples of UEs 115 as described with reference to fig. 1. In some examples, the process flow 400 may include one or more operations and procedures associated with the network entity 105 and the UE 115, which may be examples of those operations and procedures discussed with reference to fig. 2 and 3. Although specific operations may be discussed below, the operations may be performed in a different order than the example order shown, or the operations performed by a device may be performed by a different device or at a different time.

At 405, the UE115 may receive a control signal from the network entity 105 that lacks an indication (e.g., a field in a control signal) for carrier switching. In some examples, the UE115 may identify that carrier switching is enabled at the UE115 for the physical uplink control channel. In some examples, the UE115 may monitor for downlink transmissions on at least one serving cell (e.g., a primary serving cell) of a set of serving cells in a physical uplink control channel set. For example, UE115 may monitor for downlink transmissions of the primary component carrier.

At 410, UE 115 may identify that the radio resource control signal includes an indication of a carrier switch time pattern. The UE 115 may select one of the set of serving cells to send feedback information for the downlink transmission, where the selection is based on enabling carrier switching at the UE while the control signal lacks an indication for carrier switching.

At 415, if the UE 115 determines that the radio resource control signal includes an indication of a carrier switch time mode, the UE 115 may select a secondary serving cell (e.g., secondary component carrier) to send feedback information. At 420, if the UE 115 determines that the radio resource control signal does not include an indication of a carrier switch time mode, the UE 115 may select a primary serving cell (e.g., primary component carrier) to send feedback information.

Fig. 5 illustrates an example of a process flow 500 supporting performing carrier switching using fallback control information according to examples as disclosed herein. Process flow 500 may be implemented by one or more wireless devices (such as UEs), which may be examples of UEs 115 as described with reference to fig. 1. In some examples, the process flow 500 may include one or more operations and procedures associated with the network entity 105 and the UE 115, which may be examples of those operations and procedures discussed with reference to fig. 2 and 3. Although specific operations may be discussed below, the operations may be performed in a different order than the example order shown, or the operations performed by a device may be performed by a different device or at a different time.

At 505, UE 115 may receive a control signal from network entity 105 lacking an indication for carrier switching. In some examples, the UE 115 may identify that carrier switching is enabled at the UE 115 for the physical uplink control channel. In some examples, the UE 115 may monitor for downlink transmissions on at least one serving cell (e.g., a primary serving cell) of a set of serving cells in a physical uplink control channel set. For example, UE 115 may monitor for downlink transmissions of the primary component carrier.

At 510, UE 115 may identify that the radio resource control signal includes an indication of a carrier switch time pattern. The UE 115 may select one of the set of serving cells to send feedback information for the downlink transmission, where the selection is based on enabling carrier switching at the UE while the control signal lacks an indication for carrier switching.

At 515, if the UE 115 determines that the radio resource control signal includes an indication of a carrier switch time mode, the UE 115 may determine whether the control signal is received in a UE-specific search space.

At 520, if the UE 115 determines that the radio resource control signal does not include an indication of a carrier switch time mode, the UE 115 may select a primary serving cell (e.g., primary component carrier) to send feedback information.

At 525, if the UE 115 determines that the radio resource control signal includes an indication of a carrier switch time mode and the control signal is received in a UE-specific search space, the UE 115 may select a secondary serving cell (e.g., a second component carrier) to send the feedback information.

At 530, if the UE 115 determines that the radio resource control signal includes an indication of a carrier switch time mode, but the control signal is not received in the UE-specific search space, the UE 115 may select a primary serving cell (e.g., primary component carrier) to transmit the feedback information.

Fig. 6 illustrates a block diagram 600 of an apparatus 605 that supports performing carrier switching using fallback control information according to an example as disclosed herein. The device 605 may be an example of aspects of the 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 be in communication with each other (e.g., via one or more buses).

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 performing carrier switching using fallback control information). Information may be passed to other components of the device 605. The receiver 610 may utilize a single antenna or a set of multiple antennas.

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 performing carrier switching using fallback control information). 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 set of multiple antennas.

The communication manager 620, receiver 610, transmitter 615, or various combinations thereof, or various components thereof, may be examples of means for performing aspects of performing carrier switching using fallback control information as described herein. For example, the communication manager 620, the receiver 610, the transmitter 615, or various combinations or components thereof may support methods for performing one or more of the functions described herein.

In some examples, the communication manager 620, receiver 610, transmitter 615, or various combinations or components thereof may be implemented in hardware (e.g., in communication management circuitry). The hardware may include processors, digital Signal Processors (DSPs), application Specific Integrated Circuits (ASICs), field Programmable Gate Arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combinations thereof, configured as or otherwise supporting means for performing the functions described in the present disclosure. In some examples, a processor and a memory coupled to the processor may be configured to perform one or more of the functions described herein (e.g., by the processor executing instructions stored in the memory).

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

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

According to examples as disclosed herein, the communication manager 620 may support wireless communication at the UE. For example, the communication manager 620 may be configured or otherwise support means for identifying that carrier switching is enabled at the UE for the physical uplink control channel. The communication manager 620 may be configured as or otherwise support means for receiving control signals from a network entity that lack an indication for carrier switching. The communication manager 620 may be configured as or otherwise support means for monitoring for downlink transmissions on a primary serving cell of a set of multiple serving cells in a physical uplink control channel set. The communication manager 620 may be configured as or otherwise support means for selecting one of the plurality of serving cells to send feedback information for downlink transmissions, wherein the selecting is based on enabling carrier switching at the UE and receiving a physical downlink control channel lacking an indication of how to perform carrier switching. The communication manager 620 may be configured as or otherwise support means for sending feedback information for downlink transmissions to the network entity in accordance with the selection.

By including or configuring the communication manager 620 according to examples as described herein, the device 605 (e.g., a processor controlling or otherwise coupled with the receiver 610, the transmitter 615, the communication manager 620, or a combination thereof) may support techniques for reducing processing, reducing power consumption, and more efficiently utilizing communication resources.

Fig. 7 illustrates a block diagram 700 of a device 705 that supports performing carrier switching using fallback control information according to an example as disclosed herein. Device 705 may be an example of aspects of device 605 or UE 115 as described herein. 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 be in communication with each other (e.g., via one or more buses).

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 performing carrier switching using fallback control information). Information may be passed to other components of device 705. Receiver 710 may utilize a single antenna or a set of multiple antennas.

Transmitter 715 may provide a means for transmitting signals generated by other components of 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 performing carrier switching using fallback control information). 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 set of multiple antennas.

The device 705, or various components thereof, may be an example of means for performing various aspects of performing carrier switching using fallback control information as described herein. For example, communication manager 720 may include a carrier switching component 725, a control signal receiving component 730, a transmission monitoring component 735, a selection component 740, a feedback transmitting component 745, or any combination thereof. Communication manager 720 may be an example of aspects of communication manager 620 as described herein. In some examples, communication manager 720 or various components thereof may be configured to perform various operations (e.g., receive, monitor, transmit) using or otherwise in conjunction with receiver 710, transmitter 715, or both. For example, the communication manager 720 may receive information from the receiver 710, send information to the transmitter 715, or be integrated with the receiver 710, the transmitter 715, or both to receive information, send information, or perform various other operations as described herein.

According to examples as disclosed herein, the communication manager 720 may support wireless communication at the UE. The carrier switching component 725 may be configured as or otherwise support means for identifying that carrier switching is enabled at the UE for the physical uplink control channel. The control signal receiving component 730 may be configured as or otherwise support means for receiving a control signal from a network entity lacking an indication for carrier switching. The transmission monitoring component 735 may be configured as or otherwise support means for monitoring for downlink transmissions on a primary serving cell of a set of multiple serving cells in a physical uplink control channel set. The selection component 740 can be configured as or otherwise support means for selecting one of the plurality of serving cells to send feedback information for downlink transmissions, wherein the selection is based on enabling carrier switching at the UE and receiving a physical downlink control channel lacking an indication of how to perform carrier switching. The feedback sending component 745 may be configured as or otherwise support means for sending feedback information for downlink transmissions to the network entity in accordance with the selection.

Fig. 8 illustrates a block diagram 800 of a communication manager 820 that supports performing carrier switching using fallback control information in accordance with an example as disclosed herein. Communication manager 820 may be an example of aspects of communication manager 620, communication manager 720, or both, as described herein. Communication manager 820 or various components thereof may be an example of means for performing aspects of performing carrier switching using fallback control information as described herein. For example, communication manager 820 can include a carrier switching component 825, a control signal receiving component 830, a transmission monitoring component 835, a selection component 840, a feedback transmission component 845, a time mode component 850, a scheduling conflict component 855, a scanning component 860, or any combination thereof. Each of these components may communicate with each other directly or indirectly (e.g., via one or more buses).

According to examples as disclosed herein, communication manager 820 may support wireless communication at a UE. Carrier switching component 825 may be configured as or otherwise support means for identifying that carrier switching is enabled at the UE for the physical uplink control channel. The control signal receiving component 830 may be configured as or otherwise support means for receiving a control signal from a network entity that lacks an indication for carrier switching. The transmit monitoring component 835 may be configured as or otherwise support means for monitoring for downlink transmissions on a primary serving cell of a set of multiple serving cells in a physical uplink control channel set. The selection component 840 may be configured as or otherwise support means for selecting one of the plurality of serving cells to send feedback information for downlink transmissions, wherein the selection is based on enabling carrier switching at the UE and receiving a physical downlink control channel lacking an indication of how to perform carrier switching. The feedback sending component 845 may be configured as or otherwise support means for sending feedback information for downlink transmissions to the network entity in accordance with the selection.

In some examples, to support selection of one of the plurality of serving cells, the selection component 840 may be configured as or otherwise support means for selecting a primary serving cell of the UE to send feedback information for downlink transmissions.

In some examples, to support selection of one of the plurality of serving cells, the time mode component 850 may be configured as or otherwise support means for identifying that the radio resource control signal includes an indication of carrier switch time mode. In some examples, to support selection of one of the plurality of cells, the selection component 840 may be configured as or otherwise support means for selecting a primary cell or a secondary cell to send feedback information based on identifying that the radio resource control signal includes an indication of a carrier switch time pattern.

In some examples, the scheduling conflict component 855 may be configured as or otherwise support means for identifying a scheduling conflict between downlink reception and uplink transmission of feedback information for a primary serving cell. In some examples, the scanning component 860 may be configured as or otherwise support means for: scanning remaining serving cells of the set of multiple serving cells for availability of uplink resources for transmitting the feedback information according to a predefined ordering associated with a carrier switch time pattern configured for the UE; and selecting the secondary serving cell based on the availability of uplink resources on the secondary serving cell.

In some examples, to support selection of one of the plurality of serving cells, the time mode component 850 may be configured as or otherwise support means for identifying a carrier switch time mode configured for the UE by radio resource control signaling. In some examples, to support selection of one of the plurality of cells, the selection component 840 may be configured as or otherwise support means for selecting a primary or secondary cell to send feedback information based on identifying a carrier switch time pattern.

In some examples, to support selection of one of the plurality of serving cells, the time mode component 850 may be configured as or otherwise support means for identifying that the radio resource control configuration of the UE does not include a carrier switch time mode. In some examples, to support selection of one of the plurality of serving cells, the selection component 840 may be configured as or otherwise support means for selecting a primary serving cell of the UE to send feedback information based on identifying that the radio resource control configuration does not include a carrier switch time pattern.

In some examples, to support selection of one of the plurality of serving cells, the time mode component 850 may be configured as or otherwise support means for identifying that the radio resource control configuration of the UE includes a carrier switch time mode. In some examples, to support selection of one of the plurality of serving cells, control signal receiving component 830 may be configured as or otherwise support means for identifying receipt of a control signal in a UE-specific search space. In some examples, to support selection of one of the plurality of serving cells, the selection component 840 may be configured as or otherwise support means for selecting a secondary serving cell to send feedback information based on identifying that the radio resource control signal includes an indication of a carrier switch time pattern and receiving the control signal in a UE-specific search space.

In some examples, to support selection of one of the plurality of serving cells, the time mode component 850 may be configured as or otherwise support means for identifying that the radio resource control configuration includes a carrier switch time mode. In some examples, to support selection of one of the plurality of serving cells, control signal receiving component 830 may be configured as or otherwise support means for identifying that no control signal was received in the UE-specific search space. In some examples, to support selection of one of the plurality of serving cells, the selection component 840 may be configured as or otherwise support means for selecting a primary serving cell to send feedback information based on identifying a carrier switch time pattern and receiving a control signal in a UE-specific search space. In some examples, the indication of how to perform carrier switching includes DCI format 1_0 or 1_1 or 1_2.

Fig. 9 illustrates a diagram of a system 900 including a device 905 that supports performing carrier switching using fallback control information according to an example as disclosed herein. The device 905 may be, or include components of, an example of the device 605, the device 705, or the UE 115 as described herein. The device 905 may communicate wirelessly with one or more network entities 105, 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 communications manager 920, an input/output (I/O) controller 910, a transceiver 915, an antenna 925, a memory 930, code 935, and a processor 940. These components may be in electronic communication or otherwise (e.g., operatively, communicatively, functionally, electronically, electrically) coupled via one or more buses (e.g., bus 945).

The I/O controller 910 may manage input and output signals for the device 905. The I/O controller 910 may also manage peripheral devices that are not integrated into the device 905. In some cases, the I/O controller 910 may represent a physical connection or port to an external peripheral device. In some cases, I/O controller 910 may utilize an operating system such as Or another known operating system. Additionally or alternatively, the 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 the device 905 via the I/O controller 910 or via hardware components controlled by the I/O controller 910.

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 that is capable of sending or receiving multiple wireless transmissions simultaneously. As described herein, the transceiver 915 may communicate bi-directionally via one or more antennas 925, wired or wireless links. For example, transceiver 915 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 915 may also include a modem to: modulating the packet to provide the modulated packet to one or more antennas 925 for transmission; and demodulates 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 a transmitter 615, a transmitter 715, a receiver 610, a receiver 710, or any combination thereof or components thereof as described herein.

Memory 930 may include Random Access Memory (RAM) and Read Only Memory (ROM). The memory 930 may store computer-readable, computer-executable code 935 comprising instructions that, when executed by the processor 940, cause the device 905 to perform the various functions described herein. Code 935 may be stored in a non-transitory computer readable medium such as system memory or another type of memory. In some cases, while code 935 may not be directly executable by processor 940, the computer (e.g., when compiled and executed) may be caused to perform the functions described herein. In some cases, memory 930 may include, among other things, a basic I/O system (BIOS) that may control basic hardware or software operations, such as interactions with peripheral components or devices.

Processor 940 may include intelligent hardware devices (e.g., general purpose processors, DSPs, CPUs, microcontrollers, ASICs, FPGAs, programmable logic devices, discrete gate or transistor logic components, discrete hardware components, or any combinations thereof). In some cases, processor 940 may be configured to operate the memory array using a memory controller. In some other cases, the memory controller may be integrated into the processor 940. Processor 940 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 930) to cause device 905 to perform various functions (e.g., functions or tasks that support performing carrier switching using fallback control information). For example, the device 905 or components of the device 905 may include a processor 940 and a memory 930 coupled to the processor 940, the processor 940 and the memory 930 configured to perform various functions described herein.

According to examples as disclosed herein, the communication manager 920 may support wireless communication at the UE. For example, the communication manager 920 may be configured or otherwise enabled to identify that carrier switching is enabled at the UE for the physical uplink control channel. The communication manager 920 may be configured as or otherwise support means for receiving a control signal from a network entity lacking an indication for carrier switching. The communication manager 920 may be configured as or otherwise support means for monitoring for downlink transmissions on a primary serving cell of a set of multiple serving cells in a physical uplink control channel set. The communication manager 920 may be configured as or otherwise support means for selecting one of the plurality of serving cells to send feedback information for downlink transmissions, wherein the selecting is based on enabling carrier switching at the UE and receiving a physical downlink control channel lacking an indication of how to perform carrier switching. The communication manager 920 may be configured as or otherwise support means for sending feedback information for downlink transmissions to the network entity in accordance with the selection.

By including or configuring the communication manager 920 according to examples as described herein, the device 905 may support techniques for improving communication reliability, reducing latency, improving user experience associated with reduced processing, reducing power consumption, and more efficiently utilizing communication resources.

In some examples, the communication manager 920 may be configured to perform various operations (e.g., receive, monitor, transmit) using or otherwise in conjunction with the transceiver 915, one or more antennas 925, or any combination thereof. Although communication manager 920 is shown as a separate component, in some examples, one or more functions described with reference to communication manager 920 may be supported or performed by processor 940, memory 930, code 935, or any combination thereof. For example, code 935 may include instructions executable by processor 940 to cause device 905 to perform aspects of performing carrier switching using fallback control information as described herein, or the processor 940 and memory 930 may be otherwise configured to perform or support such operations.

Fig. 10 illustrates a block diagram 1000 of a device 1005 supporting performing carrier switching using fallback control information in accordance with an example as disclosed herein. Device 1005 may be an example of aspects of network entity 105 as described herein. The device 1005 may include a receiver 1010, a transmitter 1015, and a communication manager 1020. The device 1005 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

The receiver 1010 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 performing carrier switching using fallback control information). Information may be passed to other components of the device 1005. The receiver 1010 may utilize a single antenna or a set of multiple antennas.

The transmitter 1015 may provide a means for transmitting signals generated by other components of the device 1005. For example, the transmitter 1015 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 performing carrier switching using fallback control information). In some examples, the transmitter 1015 may be co-located with the receiver 1010 in a transceiver module. The transmitter 1015 may utilize a single antenna or a set of multiple antennas.

The communication manager 1020, receiver 1010, transmitter 1015, or various combinations thereof, or various components thereof, may be examples of means for performing aspects of performing carrier switching using fallback control information as described herein. For example, communication manager 1020, receiver 1010, transmitter 1015, or various combinations or components thereof, may support methods for performing one or more of the functions described herein.

In some examples, the communication manager 1020, the receiver 1010, the transmitter 1015, or various combinations or components thereof, may be implemented in hardware (e.g., in communication management circuitry). The hardware may include processors, DSP, ASIC, FPGA or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination thereof configured as or otherwise supporting the means for performing the functions described in this disclosure. In some examples, a processor and a memory coupled to the processor may be configured to perform one or more of the functions described herein (e.g., by the processor executing instructions stored in the memory).

Additionally or alternatively, in some examples, the communication manager 1020, receiver 1010, transmitter 1015, or various combinations or components thereof, may be implemented in code (e.g., as communication management software or firmware) that is executed by a processor. If implemented in code executed by a processor, the functions of communication manager 1020, receiver 1010, transmitter 1015, or various combinations or components thereof, may be performed by a general purpose processor, DSP, CPU, ASIC, FPGA, or any combination of these or other programmable logic devices (e.g., configured as or otherwise supporting means for performing the functions described in this disclosure).

In some examples, communication manager 1020 may be configured to perform various operations (e.g., receive, monitor, transmit) using or otherwise in conjunction with receiver 1010, transmitter 1015, or both. For example, communication manager 1020 may receive information from receiver 1010, send information to transmitter 1015, or be integrated with receiver 1010, transmitter 1015, or both to receive information, send information, or perform various other operations as described herein.

According to examples as disclosed herein, communication manager 1020 may support wireless communication at a network entity. For example, communication manager 1020 may be configured as or otherwise support means for identifying that carrier switching is enabled at the UE for the physical uplink control channel. The communication manager 1020 may be configured as or otherwise support means for transmitting to the UE a physical downlink control channel that does not include an indication of how to perform carrier switching. The communication manager 1020 may be configured as or otherwise support means for sending downlink transmissions to a UE on a primary serving cell of a set of multiple serving cells in a physical uplink control channel set. The communication manager 1020 may be configured as or otherwise support means for receiving feedback information for downlink transmissions from a UE, wherein the feedback information is received on one of the set of multiple serving cells configured for the UE based on enabling carrier switching and a physical downlink control channel at the UE.

By including or configuring the communication manager 1020 according to examples as described herein, the device 1005 (e.g., a processor controlling or otherwise coupled with the receiver 1010, the transmitter 1015, the communication manager 1020, or a combination thereof) can support techniques for reducing processing, reducing power consumption, and more efficiently utilizing communication resources.

Fig. 11 illustrates a block diagram 1100 of a device 1105 supporting performing carrier switching using fallback control information in accordance with an example as disclosed herein. Device 1105 may be an example of aspects of device 1005 or network entity 105 as described herein. The device 1105 may include a receiver 1110, a transmitter 1115, and a communication manager 1120. The device 1105 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

The receiver 1110 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 performing carrier switching using fallback control information). Information may be passed to other components of the device 1105. Receiver 1110 may utilize a single antenna or a set of multiple antennas.

The transmitter 1115 may provide a means for transmitting signals generated by other components of the device 1105. For example, the transmitter 1115 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 performing carrier switching using fallback control information). In some examples, the transmitter 1115 may be co-located with the receiver 1110 in a transceiver module. The transmitter 1115 may utilize a single antenna or a set of multiple antennas.

The device 1105 or various components thereof may be an example of means for performing aspects of performing carrier switching using fallback control information as described herein. For example, the communication manager 1120 can include a carrier switching component 1125, a control signaling component 1130, a downlink transmission component 1135, a feedback receiving component 1140, or any combination thereof. Communication manager 1120 may be an example of aspects of communication manager 1020 as described herein. In some examples, the communication manager 1120 or various components thereof may be configured to perform various operations (e.g., receive, monitor, transmit) using or otherwise in conjunction with the receiver 1110, the transmitter 1115, or both. For example, the communication manager 1120 may receive information from the receiver 1110, send information to the transmitter 1115, or be integrated with the receiver 1110, the transmitter 1115, or both to receive information, send information, or perform various other operations as described herein.

According to examples as disclosed herein, the communication manager 1120 may support wireless communication at a network entity. Carrier switching component 1125 may be configured as or otherwise support means for identifying that carrier switching is enabled at the UE for the physical uplink control channel. Control signal transmission component 1130 may be configured as or otherwise support means for transmitting a physical downlink control channel to a UE that does not include an indication of how to perform carrier switching. The downlink transmission component 1135 may be configured as, or otherwise support, means for sending downlink transmissions to the UE on a primary serving cell of a set of multiple serving cells in a physical uplink control channel set. The feedback reception component 1140 may be configured as or otherwise support means for receiving feedback information for downlink transmissions from a UE, wherein the feedback information is received on one of the set of multiple serving cells configured for the UE based on enabling carrier switching and physical downlink control channels at the UE.

Fig. 12 illustrates a block diagram 1200 of a communication manager 1220 that supports performing carrier switching using fallback control information, according to examples as disclosed herein. Communication manager 1220 may be an example of aspects of communication manager 1020, communication manager 1120, or both, as described herein. The communication manager 1220 or various components thereof may be an example of means for performing various aspects of performing carrier switching using fallback control information as described herein. For example, the communication manager 1220 can include a carrier switching component 1225, a control signaling component 1230, a downlink transmission component 1235, a feedback receiving component 1240, a time mode component 1245, or any combination thereof. Each of these components may communicate with each other directly or indirectly (e.g., via one or more buses).

According to examples as disclosed herein, the communication manager 1220 may support wireless communication at a network entity. Carrier switching component 1225 may be configured as or otherwise support means for identifying that carrier switching is enabled at the UE for the physical uplink control channel. The control signal transmission component 1230 may be configured as or otherwise support means for transmitting control signals to the UE that lack an indication for carrier switching. The downlink transmission component 1235 may be configured as or otherwise support means for sending downlink transmissions to the UE on a primary serving cell of a set of multiple serving cells in a physical uplink control channel set. The feedback receiving component 1240 may be configured as or otherwise support means for receiving feedback information for downlink transmissions from a UE, wherein the feedback information is received on one of the identified plurality of serving cells based on enabling carrier switching at the UE while the control signal lacks an indication for carrier switching.

In some examples, to support receiving feedback information, feedback receiving component 1240 may be configured as or otherwise support means for receiving feedback information on a primary serving cell in the set of multiple serving cells. In some examples, to support receiving feedback information, the time mode component 1245 may be configured as or otherwise support means for identifying that the radio resource control signal includes an indication of a carrier switch time mode. In some examples, to support receiving feedback information, feedback receiving component 1240 may be configured or otherwise support means for receiving feedback information on a primary or secondary serving cell based on identifying that a radio resource control signal includes an indication of a carrier switch time pattern.

In some examples, to support receiving feedback information, the time mode component 1245 may be configured as or otherwise support means for identifying that the radio resource control signal does not include an indication of carrier switch time mode. In some examples, to support receiving feedback information, feedback receiving component 1240 may be configured or otherwise support means for receiving feedback information on a primary serving cell based on identifying that a radio resource control signal does not include an indication of a carrier switch time pattern.

In some examples, to support receiving feedback information, the time mode component 1245 may be configured as or otherwise support means for identifying that the radio resource control signal includes an indication of a carrier switch time mode. In some examples, to support receiving feedback information, control signal transmission component 1230 may be configured as or otherwise support means for identifying transmission of control signals in a UE-specific search space. In some examples, to support receiving feedback information, feedback receiving component 1240 may be configured or otherwise support means for receiving feedback information on a secondary serving cell based on identifying that a radio resource control signal includes an indication of a carrier switch time pattern and transmitting a control signal in a UE-specific search space.

In some examples, to support receiving feedback information, the time mode component 1245 may be configured as or otherwise support means for identifying that the radio resource control signal includes an indication of a carrier switch time mode. In some examples, to support receiving feedback information, the control signal transmission component 1230 may be configured or otherwise support means for identifying that no control signal was transmitted in the UE-specific search space. In some examples, to support receiving feedback information, feedback receiving component 1240 may be configured or otherwise support means for receiving feedback information on a primary serving cell based on identifying that a radio resource control signal includes an indication of a carrier switch time pattern and transmitting the control signal in a UE-specific search space.

Fig. 13 illustrates a diagram of a system 1300 that includes a device 1305 that supports performing carrier switching using fallback control information according to an example as disclosed herein. Device 1305 may be or include an example of device 1005, device 1105, or network entity 105 as described herein. Device 1305 may communicate wirelessly with one or more network entities 105, UEs 115, or any combination thereof. Device 1305 may include components for bi-directional voice and data communications, including components for sending and receiving communications, such as a communications manager 1320, a network communications manager 1310, a transceiver 1315, an antenna 1325, memory 1330, code 1335, a processor 1340, and an inter-station communications manager 1345. These components may be in electronic communication or otherwise (e.g., operatively, communicatively, functionally, electronically, electrically) coupled via one or more buses (e.g., bus 1350).

The network communication manager 1310 may manage communications (e.g., via one or more wired backhaul links) with the core network 130. For example, the network communication manager 1310 may manage delivery of data communications for client devices, such as one or more UEs 115.

In some cases, device 1305 may include a single antenna 1325. However, in some other cases, device 1305 may have more than one antenna 1325 that is capable of sending or receiving multiple wireless transmissions simultaneously. As described herein, the transceiver 1315 may communicate bi-directionally via one or more antennas 1325, wired or wireless links. For example, transceiver 1315 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. Transceiver 1315 may also include a modem to: modulating the packet to provide the modulated packet to one or more antennas 1325 for transmission; and demodulates packets received from one or more antennas 1325. The transceiver 1315 or transceiver 1315 and one or more antennas 1325 may be examples of a transmitter 1015, a transmitter 1115, a receiver 1010, a receiver 1110, or any combination thereof or components thereof as described herein.

The memory 1330 may include RAM and ROM. Memory 1330 may store computer-readable, computer-executable code 1335 comprising instructions that, when executed by processor 1340, cause device 1305 to perform the various functions described herein. Code 1335 may be stored in a non-transitory computer readable medium such as system memory or another type of memory. In some cases, while code 1335 may not be directly executable by processor 1340, the computer (e.g., when compiled and executed) may be caused to perform the functions described herein. In some cases, memory 1330 may include, among other things, a BIOS that may control basic hardware or software operations, such as interactions with peripheral components or devices.

Processor 1340 may include intelligent hardware devices (e.g., a general purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, discrete gate or transistor logic components, discrete hardware components, or any combination thereof). In some cases, processor 1340 may be configured to operate the memory array using a memory controller. In some other cases, the memory controller may be integrated into the processor 1340. Processor 1340 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 1330) to cause device 1305 to perform various functions (e.g., functions or tasks that support performing carrier switching using fallback control information). For example, device 1305 or a component of device 1305 may include a processor 1340 and a memory 1330 coupled with processor 1340, the processor 1340 and memory 1330 configured to perform the various functions described herein.

The inter-station communication manager 1345 may manage communications with other network entities 105 and may include a controller or scheduler for controlling communications with UEs 115 in cooperation with other network entities 105. For example, inter-station communication manager 1345 may coordinate scheduling of transmissions to UEs 115 for various interference mitigation techniques, such as beamforming or joint transmission. In some examples, the inter-station communication manager 1345 may provide an X2 interface within the LTE/LTE-a wireless communication network technology to provide communication between the network entities 105.

According to examples as disclosed herein, the communication manager 1320 may support wireless communication at a network entity. For example, the communication manager 1320 may be configured or otherwise support means for identifying that carrier switching is enabled at the UE for the physical uplink control channel. The communication manager 1320 may be configured as or otherwise support means for transmitting control signals to the UE that lack an indication for carrier switching. The communication manager 1320 may be configured as or otherwise support means for sending downlink transmissions to a UE on a primary serving cell of a set of multiple serving cells in a physical uplink control channel set. The communication manager 1320 may be configured to receive feedback information for a downlink transmission from a UE based on enabling carrier switching at the UE while the control signal lacks an indication for carrier switching, the feedback information being received on one of the identified plurality of serving cells.

By including or configuring the communication manager 1320 in accordance with examples as described herein, the device 1305 may support techniques for improving communication reliability, reducing latency, improving user experience associated with reduced processing, reducing power consumption, more efficient utilization of communication resources, improving coordination among devices, extending battery life, and improving utilization of processing capabilities.

In some examples, the communication manager 1320 may be configured to perform various operations (e.g., receive, monitor, transmit) using or otherwise in conjunction with the transceiver 1315, one or more antennas 1325, or any combination thereof. Although communication manager 1320 is shown as a separate component, in some examples, one or more of the functions described with reference to communication manager 1320 may be supported or performed by processor 1340, memory 1330, code 1335, or any combination thereof. For example, code 1335 may include instructions executable by processor 1340 to cause device 1305 to perform aspects of carrier switching using fallback control information as described herein, or the processor 1340 and memory 1330 may be otherwise configured to perform or support such operations.

Fig. 14 illustrates a flow chart of a method 1400 of supporting performing carrier switching using fallback control information according to an example as disclosed herein. The operations of method 1400 may be implemented by a UE or components thereof as described herein. For example, the operations of method 1400 may be performed by UE 115 as described with reference to fig. 1-9. In some examples, the UE may execute a set of instructions to control functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform aspects of the described functionality.

At 1405, the method may include: carrier switching is identified as being enabled at the UE for the physical uplink control channel. 1405 may be performed according to examples as disclosed herein. In some examples, aspects of the operation of 1405 may be performed by carrier switching component 825 as described with reference to fig. 8.

At 1415, the method may include: a serving cell of a set of multiple serving cells is selected to transmit feedback information for downlink transmissions, wherein the selection is based on enabling carrier switching at the UE while a physical downlink control channel lacks a field for carrier switching. 1415 may be performed according to examples as disclosed herein. In some examples, aspects of the operation of 1415 may be performed by the selection component 840 as described with reference to fig. 8.

At 1420, the method may include: feedback information for the downlink transmission is sent to the network entity in accordance with the selection. Operations of 1420 may be performed according to examples as disclosed herein. In some examples, aspects of the operation of 1420 may be performed by the feedback sending component 845 as described with reference to fig. 8.

Fig. 15 illustrates a flow chart of a method 1500 of supporting performing carrier switching using fallback control information according to an example as disclosed herein. The operations of method 1500 may be implemented by a UE or components thereof as described herein. For example, the operations of the method 1500 may be performed by the UE 115 as described with reference to fig. 1-9. In some examples, the UE may execute a set of instructions to control functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform aspects of the described functionality.

At 1505, the method may include: carrier switching is identified as being enabled at the UE for the physical uplink control channel. The operations of 1505 may be performed according to examples as disclosed herein. In some examples, aspects of the operation of 1505 may be performed by carrier switching component 825 as described with reference to fig. 8.

At 1515, the method may include: the carrier switching time pattern configured for the UE is identified through RRC signaling. Operations of 1515 may be performed according to examples as disclosed herein. In some examples, aspects of the operation of 1515 may be performed by the temporal pattern component 850 as described with reference to fig. 8.

At 1520, the method can include: the secondary serving cell is selected to transmit feedback information based on identifying that the RRC configuration includes a carrier switch time mode. Operations of 1520 may be performed according to examples as disclosed herein. In some examples, aspects of the operation of 1520 may be performed by the selection component 840 as described with reference to fig. 8.

At 1525, the method may comprise: feedback information for the downlink transmission is sent to the network entity in accordance with the selection. Operations of 1525 may be performed according to examples as disclosed herein. In some examples, aspects of the operation of 1525 may be performed by the feedback transmission component 845 as described with reference to fig. 8.

Fig. 16 illustrates a flow diagram of a method 1600 that supports performing carrier switching using fallback control information in accordance with an example as disclosed herein. The operations of method 1600 may be implemented by a network entity or component thereof as described herein. For example, the operations of method 1600 may be performed by network entity 105 as described with reference to fig. 1-5 and 10-13. In some examples, a network entity may execute a set of instructions to control functional elements of the network entity to perform the described functions. Additionally or alternatively, the network entity may use dedicated hardware to perform aspects of the described functionality.

At 1605, the method may include: carrier switching is identified as being enabled at the UE for the physical uplink control channel. The operations of 1605 may be performed according to examples as disclosed herein. In some examples, aspects of the operation of 1605 may be performed by carrier switching component 1225 as described with reference to fig. 12.

At 1610, the method may include: a physical downlink control channel is transmitted to the UE that does not include an indication of how to perform carrier switching. The operations of 1610 may be performed according to examples as disclosed herein. In some examples, aspects of the operation of 1610 may be performed by a control signaling component 1230 as described with reference to fig. 12.

At 1615, the method may include: feedback information for the downlink transmission is received from the UE, wherein the feedback information is received on one of a set of multiple serving cells configured for the UE based on enabling carrier switching and a physical downlink control channel at the UE. 1615 may be performed according to examples as disclosed herein. In some examples, aspects of the operation of 1615 may be performed by feedback receiving component 1240 as described with reference to fig. 12.

Fig. 17 illustrates a flow diagram of a method 1700 of supporting performing carrier switching using fallback control information according to an example as disclosed herein. The operations of method 1700 may be implemented by a network entity or component thereof as described herein. For example, the operations of the method 1700 may be performed by the network entity 105 as described with reference to fig. 1-5 and 10-13. In some examples, a network entity may execute a set of instructions to control functional elements of the network entity to perform the described functions. Additionally or alternatively, the network entity may use dedicated hardware to perform aspects of the described functionality.

At 1705, the method may include: carrier switching is identified as being enabled at the UE for the physical uplink control channel. 1705 may be performed according to examples as disclosed herein. In some examples, aspects of the operation of 1705 may be performed by carrier switching component 1225 as described with reference to fig. 12.

At 1710, the method may include: a physical downlink control channel is transmitted to the UE that does not include an indication of how to perform carrier switching. Operations of 1710 may be performed according to examples as disclosed herein. In some examples, aspects of the operation of 1710 may be performed by the control signaling component 1230 as described with reference to fig. 12.

At 1715, the method may include: the identification of the radio resource control signal includes an indication of a carrier switch time pattern. 1715 may be performed according to examples as disclosed herein. In some examples, aspects of the operation of 1715 may be performed by the time mode component 1245 as described with reference to fig. 12.

At 1720, the method may include: a physical downlink control channel is identified for transmission in a UE-specific search space. Operations of 1720 may be performed according to examples as disclosed herein. In some examples, aspects of the operation of 1720 may be performed by control signaling component 1230 as described with reference to fig. 12.

At 1725, the method may include: feedback information is received on the secondary serving cell based on identifying that the radio resource control signal includes an indication of a carrier switch time pattern and transmitting a physical downlink control channel in a UE-specific search space. 1725 may be performed according to examples as disclosed herein. In some examples, aspects of the operation of 1725 may be performed by feedback receiving component 1240 as described with reference to fig. 12.

The following provides an overview of aspects of the disclosure:

Aspect 1: a method for wireless communication at a UE, the method comprising: identifying that carrier switching is enabled at the UE for a physical uplink control channel; selecting one of a plurality of serving cells to send feedback information for downlink transmissions, wherein the selecting is based at least in part on enabling carrier switching at the UE and receiving a physical downlink control channel lacking an indication of how to perform the carrier switching; and transmitting the feedback information for the downlink transmission to the network entity according to the selection.

Aspect 2: the method of aspect 1, wherein selecting one of the plurality of serving cells further comprises: a primary serving cell of the UE is selected to transmit the feedback information for the downlink transmission.

Aspect 3: the method of any one of aspects 1-2, the method further comprising: identifying, for the primary serving cell, a scheduling conflict between downlink reception and uplink transmission of the feedback information; scanning remaining ones of the plurality of serving cells for availability of uplink resources for transmitting the feedback information according to a predefined ordering associated with the carrier switch time pattern configured for the UE; and selecting the secondary serving cell based on the availability of the uplink resources on the secondary serving cell.

Aspect 4: the method of any of aspects 1-3, wherein selecting one of the plurality of serving cells further comprises: identifying a carrier switch time pattern configured for the UE by radio resource control signaling; and selecting a primary or secondary serving cell to send the feedback information based at least in part on identifying the carrier switch time pattern.

Aspect 5: the method of any one of aspects 1-4, wherein selecting one of the plurality of serving cells further comprises: identifying that a radio resource control configuration of the UE does not include a carrier switch time pattern; and selecting a primary serving cell of the UE to send the feedback information based at least in part on identifying that the radio resource control configuration does not include the carrier switch time pattern.

Aspect 6: the method of any one of aspects 1-5, wherein selecting one of the plurality of serving cells further comprises: identifying that a radio resource control configuration of the UE includes a carrier switch time pattern; identifying that a control signal is received in a UE-specific search space; and selecting a secondary serving cell to send the feedback information based at least in part on identifying that the RRC configuration includes the carrier switch time pattern and receiving the control signal in the UE-specific search space.

Aspect 7: the method of any one of aspects 1-6, wherein selecting one of the plurality of serving cells further comprises: identifying that the radio resource control configuration includes a carrier switch time pattern; identifying that the control signal was not received in the UE-specific search space; and selecting a primary serving cell to send the feedback information based at least in part on identifying that the radio resource control configuration includes the carrier switch time pattern and receiving the control signal in the UE-specific search space.

Aspect 8: the method of any one of aspects 1 to 7, the indication of how to perform the carrier switch comprising a Downlink Control Information (DCI) format 1_0 or 1_1 or 1_2.

Aspect 9: a method for wireless communication at a network entity, the method comprising: identifying that carrier switching is enabled at the UE for the physical uplink control channel; transmitting to the UE a physical downlink control channel that does not include an indication of how long to perform the carrier switch; and receiving feedback information for a downlink transmission from the UE, wherein the feedback information is received on one of a plurality of serving cells configured for the UE based at least in part on enabling carrier switching and the physical downlink control channel at the UE.

Aspect 10: the method of aspect 9, wherein receiving the feedback information further comprises: the feedback information is received on a primary serving cell of the plurality of serving cells.

Aspect 11: the method of any of aspects 9-10, wherein receiving the feedback information further comprises: identifying that the radio resource control signal includes an indication of a carrier switch time pattern; and receiving the feedback information on a primary or secondary serving cell based at least in part on the indication identifying that the radio resource control signal includes the carrier switch time pattern.

Aspect 12: the method of any of aspects 9-11, wherein receiving the feedback information further comprises: identifying that the radio resource control signal does not include an indication of a carrier switch time pattern; and receiving the feedback information on a primary serving cell based at least in part on the indication identifying that the radio resource control signal does not include the carrier switch time mode.

Aspect 13: the method of any of aspects 9-12, wherein receiving the feedback information further comprises: identifying that the radio resource control signal includes an indication of a carrier switch time pattern; identifying to transmit the physical downlink control channel in a UE-specific search space; and receiving the feedback information on a secondary serving cell based at least in part on identifying that the radio resource control signal includes the indication of the carrier switch time pattern and transmitting the physical downlink control channel in the UE-specific search space.

Aspect 14: the method of any of aspects 9-13, wherein receiving the feedback information further comprises: identifying that the radio resource control signal includes an indication of a carrier switch time pattern; identifying that the physical downlink control channel is not transmitted in a UE-specific search space; and receiving the feedback information on a primary serving cell based at least in part on identifying that the radio resource control signal includes the indication of the carrier switch time pattern and transmitting the physical downlink control channel in the UE-specific search space.

Aspect 15: the method of any one of aspects 9 to 14, the indication of how to perform the carrier switch comprising a Downlink Control Information (DCI) format 1_0 or 1_1 or 1_2.

Aspect 16: an apparatus for wireless communication, the apparatus comprising: a processor; a memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method according to any one of aspects 1 to 8.

Aspect 17: an apparatus for wireless communication, the apparatus comprising at least one means for performing the method of any one of aspects 1-8.

Aspect 18: a non-transitory computer readable medium storing code for wireless communication at a UE, the code comprising instructions executable by a processor to perform the method of any one of aspects 1-8.

Aspect 19: an apparatus for wireless communication, the apparatus comprising: a processor; a memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method according to any one of aspects 9 to 15.

Aspect 20: an apparatus for wireless communication, the apparatus comprising at least one means for performing the method of any one of aspects 9-15.

Aspect 21: a non-transitory computer readable medium storing code for wireless communication at a network entity, the code comprising instructions executable by a processor to perform the method of any one of aspects 9 to 15.

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

Although aspects of the LTE, LTE-A, LTE-a Pro or NR system may be described for exemplary 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.

The information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

The various illustrative blocks and components described in connection with the disclosure herein may be implemented or performed with 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. Although a general purpose processor may be a microprocessor, in the alternative, the processor may be any processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. When implemented in software for execution by a processor, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Other examples and 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, hardwired or a combination of any of these. Features that implement the functions may also be physically located at different locations, including portions that are distributed such that the functions are implemented at different physical locations.

Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. Non-transitory storage media can be any available media that can be accessed by a general purpose or special purpose computer. By way of example, and not limitation, non-transitory computer readable media can comprise RAM, ROM, electrically Erasable Programmable ROM (EEPROM), flash memory, compact Disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that can be used to carry or store desired program code means in the form of instructions or data structures and that can be accessed by a general purpose or special purpose computer, or a general purpose or special purpose processor. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital Subscriber Line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of computer-readable medium. Disk and disc, as used herein, includes CD, laser disc, optical disc, digital Versatile Disc (DVD), floppy disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.

As used herein (including in the claims), an "or" used in an item enumeration (e.g., an item enumeration accompanied by a phrase such as "at least one of … …" or "one or more of … …") indicates an inclusive enumeration, such that, for example, enumeration 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). Furthermore, as used herein, the phrase "based on" should not be construed as a reference to a closed set of conditions. For example, example steps described as "based on condition a" may 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".

The term "determining" encompasses a wide variety of actions, and as such, "determining" may include calculating, computing, processing, deriving, exploring, looking up (such as via looking up in a table, database or other data structure), ascertaining and the like. In addition, "determining" may include receiving (such as receiving information), accessing (such as accessing data in memory), and the like. Additionally, "determining" may include parsing, selecting, choosing, establishing, and other such similar actions.

In the drawings, similar components or features may have the same reference numerals. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If only the first reference number is used in the specification, the description may be applied to any one of the similar components having the same first reference number, regardless of the second reference number or other subsequent reference numbers.

The description set forth herein in connection with the appended drawings describes example configurations and is not intended to represent all examples that may be practiced or otherwise within the scope of the claims. The term "example" as used herein means "serving as an example, instance, or illustration," rather than "preferred" or "advantageous over other examples. The detailed description includes specific details for providing an understanding of the technology. However, the techniques may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form in order to avoid obscuring the concepts of the examples.

The description herein is provided to enable any person skilled in the art to make or use the disclosure. Various modifications to the disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not intended to be limited to the examples and designs described herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (30)

1. A method for wireless communication at a User Equipment (UE), the method comprising:

Identifying that carrier switching is enabled at the UE for a physical uplink control channel;

selecting one of a plurality of serving cells to send feedback information for downlink transmissions, wherein the selecting is based at least in part on enabling carrier switching at the UE and receiving a physical downlink control channel lacking an indication of how to perform the carrier switching; and

And sending the feedback information for the downlink transmission to a network entity according to the selection.

2. The method of claim 1, wherein selecting one of the plurality of serving cells further comprises:

A primary serving cell of the UE is selected to transmit the feedback information for the downlink transmission.

3. The method of claim 2, the method further comprising:

Identifying, for the primary serving cell, a scheduling conflict between downlink reception and uplink transmission of the feedback information; and

Scanning remaining ones of the plurality of serving cells for availability of uplink resources for transmitting the feedback information according to a predefined ordering associated with a carrier switch time pattern configured for the UE; and

The secondary serving cell is selected according to the availability of the uplink resources on the secondary serving cell.

4. The method of claim 1, wherein selecting one of the plurality of serving cells further comprises:

identifying a carrier switch time pattern configured for the UE by Radio Resource Control (RRC) signaling; and

The method further includes selecting a primary serving cell or a secondary serving cell to send the feedback information based at least in part on the indication identifying the carrier switch time pattern.

5. The method of claim 1, wherein selecting one of the plurality of serving cells further comprises:

identifying that a Radio Resource Control (RRC) configuration of the UE does not include a carrier switch time pattern; and

The method further includes selecting a primary serving cell of the UE to send the feedback information based at least in part on identifying that the RRC configuration does not include the carrier switch time mode.

6. The method of claim 1, wherein selecting one of the plurality of serving cells further comprises:

identifying that a Radio Resource Control (RRC) configuration of the UE includes a carrier switch time mode;

identifying that the physical downlink control channel is received in a UE-specific search space; and

A secondary serving cell is selected to transmit the feedback information based at least in part on identifying that the RRC configuration includes the carrier switch time pattern and receiving the physical downlink control channel in the UE-specific search space.

7. The method of claim 1, wherein selecting one of the plurality of serving cells further comprises:

identifying that a Radio Resource Control (RRC) configuration of the UE includes a carrier switch time mode;

identifying that the physical downlink control channel was not received in the UE-specific search space; and

A primary serving cell is selected to transmit the feedback information based at least in part on the carrier switch time pattern and the physical downlink control channel received in the UE-specific search space.

8. The method of claim 1, wherein the indication of how to perform the carrier switch comprises Downlink Control Information (DCI) format 1_0 or 1_1 or 1_2.

9. A method for wireless communication at a network entity, the method comprising:

identifying that carrier switching is enabled at a User Equipment (UE) for a physical uplink control channel;

Transmitting to the UE a physical downlink control channel that does not include an indication of how to perform the carrier switch; and

Feedback information for a downlink transmission is received from the UE, wherein the feedback information is received on one of a plurality of serving cells configured for the UE based at least in part on enabling carrier switching and the physical downlink control channel at the UE.

10. The method of claim 9, wherein receiving the feedback information further comprises:

The feedback information is received on a primary serving cell of the plurality of serving cells.

11. The method of claim 9, wherein receiving the feedback information further comprises:

Identifying that the radio resource control signal includes an indication of a carrier switch time pattern; and

The feedback information is received on a primary serving cell or a secondary serving cell based at least in part on identifying that the radio resource control signal includes the indication of the carrier switch time pattern.

12. The method of claim 9, wherein receiving the feedback information further comprises:

Identifying that the radio resource control signal does not include an indication of a carrier switch time pattern; and

The feedback information is received on a primary serving cell based at least in part on identifying that the radio resource control signal does not include the indication of the carrier switch time mode.

13. The method of claim 9, wherein receiving the feedback information further comprises:

identifying that the radio resource control signal includes an indication of a carrier switch time pattern;

identifying to transmit the physical downlink control channel in a UE-specific search space; and

The feedback information is received on a secondary serving cell based at least in part on identifying that the radio resource control signal includes the indication of the carrier switch time pattern and transmitting the physical downlink control channel in the UE-specific search space.

14. The method of claim 9, wherein receiving the feedback information further comprises:

identifying that the radio resource control signal includes an indication of a carrier switch time pattern;

Identifying that the physical downlink control channel is not transmitted in a UE-specific search space; and

The feedback information is received on a primary serving cell based at least in part on identifying that the radio resource control signal includes the indication of the carrier switch time pattern and transmitting the physical downlink control channel in the UE-specific search space.

15. The method of claim 9, wherein the indication of how to perform the carrier switch comprises Downlink Control Information (DCI) format 1_0 or 1_1 or 1_2.

16. An apparatus for wireless communication, the apparatus comprising:

A processor;

a memory coupled with the processor; and

Instructions stored in the memory and executable by the processor to cause the apparatus to:

identifying that carrier switching is enabled at a User Equipment (UE) for a physical uplink control channel;

selecting one of a plurality of serving cells to send feedback information for downlink transmissions, wherein the selecting is based at least in part on enabling carrier switching at the UE and receiving a physical downlink control channel lacking an indication of how to perform the carrier switching; and

And sending the feedback information for the downlink transmission to the network entity according to the selection.

17. The apparatus of claim 16, wherein the instructions for selecting one of the plurality of serving cells are further executable by the processor to cause the apparatus to:

A primary serving cell of the UE is selected to transmit the feedback information for the downlink transmission.

18. The apparatus of claim 16, wherein the instructions for selecting one of the plurality of serving cells are further executable by the processor to cause the apparatus to:

Identifying that the radio resource control signal includes an indication of a carrier switch time pattern; and

A primary or secondary serving cell is selected to transmit the feedback information based at least in part on identifying that the radio resource control signal includes the indication of the carrier switch time mode.

19. The device of claim 18, wherein the instructions are further executable by the processor to cause the device to:

Identifying, for the primary serving cell, a scheduling conflict between downlink reception and uplink transmission of the feedback information; and

Scanning remaining ones of the plurality of serving cells for availability of uplink resources for transmitting the feedback information according to a predefined ordering associated with the carrier switch time pattern configured for the UE; and

The secondary serving cell is selected according to the availability of the uplink resources on the secondary serving cell.

20. The apparatus of claim 16, wherein the instructions for selecting one of the plurality of serving cells are further executable by the processor to cause the apparatus to:

identifying that a Radio Resource Control (RRC) configuration of the UE does not include a carrier switch time pattern; and

The method further includes selecting a primary serving cell of the UE to send the feedback information based at least in part on identifying that the RRC configuration does not include the carrier switch time mode.

21. The apparatus of claim 16, wherein the instructions for selecting one of the plurality of serving cells are further executable by the processor to cause the apparatus to:

identifying that a Radio Resource Control (RRC) configuration of the UE includes a carrier switch time mode;

identifying that the physical downlink control channel is received in a UE-specific search space; and

A secondary serving cell is selected to transmit the feedback information based at least in part on identifying that the RRC configuration includes the carrier switch time pattern and receiving the physical downlink control channel in the UE-specific search space.

22. The apparatus of claim 16, wherein the instructions for selecting one of the plurality of serving cells are further executable by the processor to cause the apparatus to:

identifying that a Radio Resource Control (RRC) configuration of the UE includes a carrier switch time mode;

identifying that the physical downlink control channel was not received in the UE-specific search space; and

A primary serving cell is selected to transmit the feedback information based at least in part on the carrier switch time pattern and the physical downlink control channel received in the UE-specific search space.

23. The apparatus of claim 16, wherein the indication of how to perform the carrier switch comprises Downlink Control Information (DCI) format 1_0 or 1_1 or 1_2.

24. An apparatus for wireless communication, the apparatus comprising:

A processor;

a memory coupled with the processor; and

Instructions stored in the memory and executable by the processor to cause the apparatus to:

identifying that carrier switching is enabled at a User Equipment (UE) for a physical uplink control channel;

Transmitting to the UE a physical downlink control channel that does not include an indication of how to perform the carrier switch; and

Feedback information for a downlink transmission is received from the UE, wherein the feedback information is received on one of a plurality of serving cells configured for the UE based at least in part on enabling carrier switching and the physical downlink control channel at the UE.

25. The device of claim 24, wherein the instructions for receiving the feedback information are further executable by the processor to cause the device to:

The feedback information is received on a primary serving cell of the plurality of serving cells.

26. The device of claim 24, wherein the instructions for receiving the feedback information are further executable by the processor to cause the device to:

Identifying that the radio resource control signal includes an indication of a carrier switch time pattern; and

The feedback information is received on a primary serving cell or a secondary serving cell based at least in part on identifying that the radio resource control signal includes the indication of the carrier switch time pattern.

27. The device of claim 24, wherein the instructions for receiving the feedback information are further executable by the processor to cause the device to:

Identifying that the radio resource control signal does not include an indication of a carrier switch time pattern; and

The feedback information is received on a primary serving cell based at least in part on identifying that the radio resource control signal does not include the indication of the carrier switch time mode.

28. The device of claim 24, wherein the instructions for receiving the feedback information are further executable by the processor to cause the device to:

identifying that the radio resource control signal includes an indication of a carrier switch time pattern;

identifying to transmit the physical downlink control channel in a UE-specific search space; and

The feedback information is received on a secondary serving cell based at least in part on identifying that the radio resource control signal includes the indication of the carrier switch time pattern and transmitting the physical downlink control channel in the UE-specific search space.

29. The device of claim 24, wherein the instructions for receiving the feedback information are further executable by the processor to cause the device to:

identifying that the radio resource control signal includes an indication of a carrier switch time pattern;

Identifying that the physical downlink control channel is not transmitted in a UE-specific search space; and

The feedback information is received on a primary serving cell based at least in part on identifying that the radio resource control signal includes the indication of the carrier switch time pattern and transmitting the physical downlink control channel in the UE-specific search space.

30. The apparatus of claim 24, wherein the indication of how to perform the carrier switch comprises Downlink Control Information (DCI) format 1_0 or 1_1 or 1_2.