Patent Description:
Some wireless communications systems may support UEs operating in a DRX mode. UEs in a DRX mode may transition between a sleep state for power conservation and an active state for data transmission and reception (during an ON-duration) according to a DRX configuration.

<CIT> discloses a terminal device and an uplink data transmission technology, which can achieve battery consumption reduction and can also process, without delay, various low latency services to be newly provided in <NUM>.

The described techniques relate to improved methods, systems, devices, and apparatuses that support discontinuous reception (DRX) wakeup techniques. In accordance with various aspects, a user equipment (UE) wakes up from a sleep mode of a DRX cycle based on receipt of uplink data, and initiate a transmission to a base station prior to a scheduled ON duration of the DRX cycle and in some cases prior to receiving one or more reference signals after transitioning out of the sleep mode. The UE determines if an elapsed time between a prior receipt of one or more reference signals and the transmission to the base station after waking up from the sleep mode is less than a threshold time value. If the elapsed time is less than the threshold value, the UE transmits an uplink transmission associated with the received uplink data (e.g., a scheduling request or a random access channel (RACH) request message) prior to receiving one or more reference signals that may be used to update transmission parameters for uplink transmissions. If the elapsed time is at or above the threshold value, the UE waits to receive the one or more reference signals and update the transmission parameters prior to the uplink transmission.

A corresponding method of wireless communications at a UE is described.

An apparatus for wireless communications at a UE is described. The apparatus may include a processor, memory coupled with the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to perform the method above specified.

A wireless device, such as a user equipment (UE), may implement a discontinuous reception (DRX) cycle (e.g., a connected mode DRX (C-DRX) mode) where the UE transitions between an active state (e.g., where the UE wakes up to determine if data is available for the UE) and a sleep state (e.g., where the UE shuts down various hardware/processes to conserve power). Such DRX cycles may enable the efficient use of battery power for reception of downlink transmissions. In some cases, a base station and a UE may establish a radio resource control (RRC) connection and the UE may enter a sleep state of the DRX cycle when not actively communicating with the base station. For example, during RRC connection establishment, a DRX configuration, including timing for one or more DRX-On durations, may be configured in an RRC connection setup request or an RRC connection reconfiguration request. Between successive DRX-ON durations, the UE may transition to sleep mode where one or more components of a radio frequency (RF) chain (e.g., a baseband receiver and associated amplifiers) may be powered down to help conserve power. The DRX configuration may determine how frequently the UE is scheduled to wakeup and be available for receiving downlink transmissions in accordance with the configured DRX cycle durations. It is noted that in various examples discussed herein, reference is made to the UE transitioning between sleep and awake modes with the understanding that such modes refer to sleep and awake modes for components of the RF chain, and that other components of the UE (e.g., an applications processor, user interface, etc.) may be active during such sleep and awake modes.

In some cases, in addition to the scheduled wakeup durations of the UE that are configured in the DRX cycle, the UE may also wake up at unscheduled times in response to arrival of uplink data to be transmitted from the UE. For example, a UE may be in a sleep mode of a DRX cycle and, during the sleep mode, uplink data for transmission from the UE arrives in an uplink transmission buffer (e.g., when an application running at the UE generates uplink data to be transmitted from the UE). Such unscheduled wakeup procedures may be referred to in some cases as "rude" wake ups due to their arrival during a DRX sleep cycle rudely awakening the UE. In such cases, the UE may immediately wake up and initiate a procedure to obtain uplink resources for transmission of the uplink data. For example, the UE may power on the RF components that were in sleep mode and transmit a scheduling request (SR) or a random access channel (RACH) request to obtain uplink resources to transmit the uplink data. The transmission of the SR or RACH request by the UE may provide an indication to the base station that the UE is no longer in sleep mode and that the base station can schedule communications with the UE outside of the configured DRX-ON duration.

In some cases, one or more uplink transmission parameters of the UE may become out-of-date due to the UE being in sleep mode and not keeping such parameters updated. For example, one or more of an automatic gain control (AGC) loop, a frequency tracking loop (FTL), or a power delay profile (PDP) loop at a wireless modem of the UE may be periodically updated based on one or more measurements made at the UE of one or more pilot signals or reference signals transmitted by the base station (e.g., a tracking reference signal (TRS), channel state information reference signal (CSI-RS), synchronization signal (SS) in a synchronization signal block (SSB), etc.). In some cases, the UE may update such uplink transmission parameters prior to the uplink transmission to the base station, which may enhance the likelihood of successful reception of the uplink transmission at the base station, at the cost of latency added while the UE performs the update to the uplink transmission parameters.

In accordance with various aspects of the present disclosure, a UE may determine an elapsed time since a prior update of one or more transmission parameters and may initiate an uplink SR or RACH transmission prior to a subsequent update of the transmission parameters if the elapsed time is less than a threshold value. If the elapsed time meets or exceeds the threshold value the UE may wait until the one or more parameters are updated (e.g., wait for a subsequent reference signal from the base station and associated measurement procedures to update the transmission parameters). Such techniques may allow a UE to transmit an SR or RACH request relatively quickly upon the arrival of uplink data, and thus enhance UE performance by reducing latency associated with the uplink transmission. In some cases, the threshold value may be set such that error in one or more tracking loops is likely to be relatively small and thus provide a reliable uplink transmission of the UE. Further, such techniques may allow for update of the one or more transmission parameters in parallel with the SR or RACH transmission, and thus the UE may update the uplink transmission parameters prior to uplink data transmissions that may follow the SR or RACH transmissions. Such techniques may thus provide a key performance indicator (KPI) such as "mobile originated ping latency" that is a relatively low value compared to cases where a UE always waits to update transmission parameters prior to an uplink transmission. Such KPI performance may indicate relatively efficient communications between the UE and base station while also providing relatively low power consumption at the UE.

For instance, the methods described may be performed in an order different from that described, and various operations may be added, omitted, or combined.

Aspects of the disclosure are initially described in the context of a wireless communications system. Example timelines and process flows illustrating aspects of the discussed techniques are then described. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to DRX wakeup techniques.

<FIG> illustrates an example of a wireless communications system <NUM> that supports DRX wakeup techniques in accordance with aspects of the present disclosure. The wireless communications system <NUM> includes base stations <NUM>, UEs <NUM>, and a core network <NUM>. In some examples, the wireless communications system <NUM> may be a Long Term Evolution (LTE) network, an LTE-Advanced (LTE-A) network, an LTE-A Pro network, or a New Radio (NR) network. In some cases, wireless communications system <NUM> may support enhanced broadband communications, ultra-reliable (e.g., mission critical) communications, low latency communications, or communications with low-cost and low-complexity devices.

In some examples, half-duplex communications may be performed at a reduced peak rate.

For example, wireless communications system <NUM> may use a transmission scheme between a transmitting device (e.g., a base station <NUM>) and a receiving device (e.g., a UE <NUM>), where the transmitting device is equipped with multiple antennas and the receiving device is equipped with one or more antennas.

A carrier may be associated with a pre-defined frequency channel (e.g., an evolved universal mobile telecommunication system terrestrial radio access (E-UTRA) absolute radio frequency channel number (EARFCN)), and may be positioned according to a channel raster for discovery by UEs <NUM>. In some examples, signal waveforms transmitted over a carrier may be made up of multiple sub-carriers (e.g., using multi-carrier modulation (MCM) techniques such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM)).

The organizational structure of the carriers may be different for different radio access technologies (e.g., LTE, LTE-A, LTE-A Pro, NR).

In some cases, UEs <NUM> and base stations <NUM> may be configured with DRX cycles that allow one or more UEs <NUM> to transition to a power-saving sleep mode between ON durations of the DRX cycles. In some cases, a UE <NUM> may wake up from sleep mode of a DRX cycle based on receipt of uplink data, and initiate a transmission to a base station <NUM> prior to a scheduled ON duration of the DRX cycle and in some cases prior to updating one or more transmission parameters after transitioning out of the sleep mode. In some cases, the UE <NUM> initiate the transmission prior to updating the one or more transmission parameters if an elapsed time since a prior update is less than a threshold time value. If the elapsed time is less than the threshold time value, the UE <NUM> may transmit an uplink transmission associated with the received uplink data (e.g., an SR or RACH request message) prior to receiving one or more reference signals that may be used to update the transmission parameters. If the elapsed time is at or above the threshold value, the UE <NUM> may wait to receive the one or more reference signals and update the transmission parameters prior to the uplink transmission.

<FIG> illustrates an example of a wireless communications system <NUM> that supports DRX wakeup techniques in accordance with aspects of the present disclosure. In some examples, wireless communications system <NUM> may implement aspects of wireless communications system <NUM>. For example, the wireless communications system <NUM> may include a base station <NUM>-a and a UE <NUM>-a, which may be examples of the corresponding devices described with reference to <FIG>. Some examples of the wireless communications system <NUM> may support DRX techniques for reduced power consumption at the UE <NUM>-a.

The base station <NUM>-a may provide a network coverage for UE <NUM>-a within geographic coverage area <NUM>-a. In some examples, UE <NUM>-a may support DRX operation for improved power efficiency. For example, a UE <NUM>-a may operate according to a DRX configuration in which the UE <NUM>-a monitors for communications during periodic ON-durations, and transitions to a low power sleep mode between the periodic ON-durations. The time period between the start of each ON-duration may be referred to as a cycle duration. Further, in some cases, DRX cycles may have an identified starting location (e.g., at the start of an identified slot within a subframe), and a configurable ON-duration (e.g., <NUM> slots) that starts at an offset (e.g., <NUM> slots) relative to the identified starting location.

The base station <NUM>-a may transmit downlink communications <NUM> to the UE <NUM>-a, and the UE <NUM>-a may transmit uplink communications <NUM> to the base station <NUM>-a. In some cases, as will be discussed in more detail with respect to <FIG>, the base station <NUM>-a and UE <NUM>-a, when performing an RRC connection establishment or reestablishment, may configure a DRX configuration in which the UE <NUM>-a may transition to a sleep mode between ON durations of the DRX cycle in order to reduce power consumption. In some cases, the UE <NUM>-a may set one or more uplink and/or downlink transmission parameters for communications with the base station <NUM>-a based on measurements that are made from one or more periodic pilot signals <NUM> that are transmitted by the base station <NUM>-a (e.g., one or more TRS, CSI-RS, SSB transmissions, or combinations thereof). For example, the UE <NUM>-a may maintain one or more tracking loops associated with the one or more transmission or reception parameters (e.g., one or more AGC, FTL, PDP loops, or combinations thereof) that may be updated based on measurements of the one or more periodic pilot signals <NUM>.

In some cases as discussed herein, the UE <NUM>-a may receive uplink data that is to be transmitted to the base station <NUM>-a, such as in an uplink buffer of the UE <NUM>-a. Upon receipt of the uplink data, the UE <NUM>-a may transmit an uplink request <NUM> to the base station <NUM>-a, such as an SR on a physical uplink control channel (PUCCH) or RACH request, to request uplink resources for transmission of the uplink data received in the uplink buffer of the UE <NUM>-a. In some systems, such as in NR systems, the periodic pilot signals <NUM> of the base station <NUM>-a (e.g., SSB/TRS transmissions) may be relatively scarce relative to pilots of other systems (e.g., LTE pilot signals), such as once every <NUM>. In such cases, if the UE <NUM>-a were to wait for a subsequent periodic pilot signal <NUM> after arrival of uplink data in order to update its transmission/reception parameters, the UE <NUM>-a could wait for up to <NUM>, and an average of <NUM>, which may add a significant amount of latency to the timing of the associated uplink request <NUM>. Thus, in such cases, waiting for SSB or TRS in order to update the one or more UE <NUM>-a tracking loops can become a dominant factor in the duration of the wakeup process.

Thus, techniques as discussed herein may provide that the UE <NUM>-a may initiate the transmission of the uplink request <NUM>, and/or transmission/reception of other physical channels, prior to receiving a subsequent periodic pilot signal <NUM> from the base station <NUM>-a if an elapsed time since a prior tracking loop update is less than a threshold time value. If the elapsed time is at or above the threshold value, the UE <NUM>-a may wait to receive the one or more periodic pilot signals <NUM> and update the transmission parameters prior to the transmission of the uplink request <NUM>.

<FIG> illustrate examples of uplink transmission timelines <NUM> and <NUM>, respectively, that support DRX wakeup techniques in accordance with aspects of the present disclosure. In some examples, uplink transmission timeline <NUM> and <NUM> may implement aspects of wireless communications system <NUM> or <NUM>. In the example of <FIG>, a base station (e.g., a base station <NUM> of <FIG> or <FIG>) may transmit one or more reference signals <NUM> according to a configuration for periodic reference signal transmissions. In this example, a first reference signal <NUM>-a and a second reference signal <NUM>-b may be transmitted by the base station.

A UE that may be operating according to a DRX configuration may monitor for some or all of the periodic reference signals <NUM> and may update one or more uplink or downlink transmission parameters based on measurements of the periodic reference signals <NUM>. In this example, the UE may monitor for and measure the first reference signal <NUM>-a and may then transition to a sleep mode <NUM>. The UE, in this example, may initiate a timer associated with the first reference signal <NUM>-a, and a time threshold <NUM> may be set against the timer, where if the UE determines an uplink transmission is needed (e.g., due to receipt of uplink data for transmission), the UE may initiate an uplink transmission prior to receipt of the second reference signal <NUM>-b, as is illustrated in <FIG>. In the example of <FIG>, the UE does not receive uplink data to be transmitted, and may remain in the sleep mode <NUM> until the start of ON duration <NUM> that is established in the DRX configuration. The UE may then monitor for a physical downlink control channel (PDCCH) downlink transmission <NUM> during the ON duration <NUM> to determine if downlink or uplink resources are configured for the UE.

In the example of <FIG>, after the UE transitions to sleep mode <NUM>, the UE may identify an uplink data arrival <NUM> or other need to access uplink resources. For example, the UE may determine that data has arrived in an uplink transmission buffer from an application processor that is running at the UE or is otherwise connected to the UE. In this example, the uplink data arrival <NUM> may occur prior to the expiration of the time threshold <NUM>, and the UE may transmit uplink transmission <NUM>, such as an SR (e.g., if a PUCCH is configured with SR resources) or a random access request (RAR) using identified RACH resources. The uplink transmission <NUM> may be transmitted prior to receipt and measurement of the second reference signal <NUM>-b based on the uplink data arrival <NUM> being prior to the expiration of the time threshold <NUM>. In other cases, the uplink data arrival <NUM> may occur after expiration of the time threshold <NUM>, in which case the UE may wait to receive and measure the second reference signal <NUM>-b before the uplink transmission <NUM>. In some cases, the starting time of the uplink transmission <NUM> may be compared to the time threshold <NUM> to determine whether the UE is to wait for the second reference signal <NUM>-b or not. In the example of <FIG>, the UE may then transition to an awake mode <NUM> and may monitor for the second reference signal <NUM>-b and perform one or more update procedures based on the second reference signal <NUM>-b. The UE may, in the awake mode <NUM>, monitor for PDCCH transmission <NUM>, which may occur in the prior scheduled ON duration <NUM>, or may occur prior to the scheduled ON duration <NUM>.

In some examples, the time threshold <NUM> may be a time value that is selected to provide a relatively reliable uplink transmission <NUM> and downlink transmission <NUM>. For example, the time threshold <NUM> may be a preconfigured time threshold (e.g., <NUM>) that is based on a worst-case timing drift due to temperature variation of UE components. In other cases, the time threshold <NUM> may be preconfigured to span a certain number of reference signal <NUM> transmissions (e.g., no more than <NUM> or <NUM> reference signal transmissions). In other cases, the time threshold <NUM> may be set based on conditions at the UE, such as based on a current temperature indicated by one or more components of the UE (e.g., a temperature indicated by an RF baseband processor, low noise amplifier (LNA) component, antenna module, etc.). For example, a first time threshold (e.g., <NUM>) may be set if the current temperature is less than a predetermined value, and a second time threshold (e.g., <NUM>) may be set if the current temperature is above the predetermined value (e.g., due to a larger amount of timing drift at higher temperatures). Thus, if a time since a prior loop update is less than the time threshold <NUM>, the UE may skip the loop update for any common C-DRX configuration, and move directly to the uplink transmission <NUM>.

Thus, the latency associated with the uplink transmission <NUM> may be improved relative to cases where the UE would wait to make an uplink transmission. For example, rather than waiting for an average of <NUM> for a SSB/TRS and then performing measurement and processing that may add additional time (e.g., an additional <NUM>-<NUM> to perform measurement, clock programming, firmware processing, and RF chain configuration), the UE may skip to the processing operations that may reduce latency, on average, by more than half relative to waiting for a subsequent SSB/TRS. As indicated herein, in some aspects, the time threshold <NUM> may be selected to provide a potential timing error that is relatively low and within requirements of the UE. Further, in a worst case a retransmission of the uplink transmission <NUM> (and/or a downlink transmission) may be required, which may still occur, on average, prior to receipt of the second reference signal <NUM>-b, and thus still provide lower latency than waiting for the second reference signal <NUM>-b prior to the SR/RAR transmission.

<FIG> illustrates an example of a process flow <NUM> that supports DRX wakeup techniques in accordance with aspects of the present disclosure. The process flow <NUM> may include a base station <NUM>-b and a UE <NUM>-b, which may be examples of the corresponding devices described with reference to <FIG>. In some examples, the process flow <NUM> may implement aspects of the wireless communications systems <NUM> and <NUM>. For example, the base station <NUM>-b and the UE <NUM>-b may support DRX operations as discussed herein.

In the following description of the process flow <NUM>, the operations between the base station <NUM>-b and the UE <NUM>-b may be transmitted in a different order than the exemplary order shown, or the operations performed by the base station <NUM>-b and the UE <NUM>-b may be performed in different orders or at different times. Certain operations may also be left out of the process flow <NUM>, or other operations may be added to the process flow <NUM>.

The process flow <NUM> may, in some examples, commence at <NUM> with the base station <NUM>-b establishing a connection with the UE <NUM>-b (e.g., performing a cell acquisition procedure, a random access procedure, an RRC connection procedure, an RRC configuration procedure).

At <NUM>, the base station <NUM>-b may determine a DRX configuration (e.g., C-DRX configuration) for the UE <NUM>-b. In some cases, the base station <NUM>-b may determine the DRX configuration to provide ON-durations at the UE <NUM>-b that correspond with a determined traffic periodicity, which may reduce power consumption at the UE <NUM>-b. At <NUM>, the base station <NUM>-b may transmit DRX configuration information to the UE <NUM>-b. In some cases, the DRX configuration may be provided in RRC signaling. In some cases, as part of the connection establishment, the UE <NUM>-b may indicate a capability for DRX configurations, and the base station <NUM>-b may enable this capability with the DRX configuration information. Additionally or alternatively, all or part of the DRX configuration information may be provided in downlink control information (DCI) or in one or more MAC-CEs.

At <NUM>, the UE <NUM>-b may determine the DRX configuration. In some cases, the UE <NUM>-b may determine the DRX configuration based on RRC signaling from the base station <NUM>-b. At <NUM>, the base station <NUM>-b may transmit periodic reference signals (e.g., SSB, TRS, CSI-RS transmissions, or combinations thereof), and the UE <NUM>-b may monitor for one or more of the periodic reference signals. At <NUM>, the UE <NUM>-b may perform reference signal measurements and update one or more tracking loops, and initiate DRX procedures based on the DRX configuration. Such DRX procedures may include the UE <NUM>-b transitioning to a sleep mode between ON-durations, and transitioning to an awake mode to monitor for downlink transmissions from the base station <NUM>-b during ON-durations.

At <NUM>, the UE <NUM>-b may detect an uplink data arrival. In some cases, the uplink data arrival may be indicated by the presence of data in an uplink transmit buffer of the UE <NUM>-b. For example, an application running at an application processor associated with the UE <NUM>-a, while the UE <NUM>-b is in a DRX sleep mode, may generate uplink data that is to be transmitted to the base station <NUM>-b. The arrival of the uplink data may cause the UE <NUM>-b to transition out of the sleep mode and into an awake state for transmission of a request to obtain resources for transmission of the uplink data and reception of downlink transmissions.

At <NUM>, the UE <NUM>-b may determine that a time threshold since the prior reference signal measurement or tracking loop update has not elapsed. In some cases, such a determination may be made based on a timer that is started at each tracking loop update. In some cases, a time of a prior reference signal measurement or tracking loop update may be recorded and compared to a subsequent time associated with the uplink data arrival or expected transmission time of the uplink request to determine if the time threshold has elapsed.

At <NUM>, based on the determination that the time threshold has not elapsed, the UE <NUM>-b may transmit an uplink request, such as an SR or RACH transmission, prior to monitoring for and measuring a subsequent reference signal transmission from the base station <NUM>-b. In this example, at <NUM>, the UE <NUM>-b may perform one or more reference signal measurements and update one or more transmission parameters based on tracking loop updated, in parallel with the downlink reception and uplink transmission processes.

<FIG> illustrates an example of a process flow <NUM> that supports DRX wakeup techniques in accordance with aspects of the present disclosure. The process flow <NUM> may include a base station <NUM>-c and a UE <NUM>-c, which may be examples of the corresponding devices described with reference to <FIG>. In some examples, the process flow <NUM> may implement aspects of the wireless communications systems <NUM> and <NUM>. For example, the base station <NUM>-c and the UE <NUM>-c may support DRX operations as discussed herein.

In the following description of the process flow <NUM>, the operations between the base station <NUM>-c and the UE <NUM>-c may be transmitted in a different order than the exemplary order shown, or the operations performed by the base station <NUM>-c and the UE <NUM>-c may be performed in different orders or at different times. Certain operations may also be left out of the process flow <NUM>, or other operations may be added to the process flow <NUM>.

The process flow <NUM> may, in some examples, commence at <NUM> with the base station <NUM>-c establishing a connection with the UE <NUM>-c (e.g., performing a cell acquisition procedure, a random access procedure, an RRC connection procedure, an RRC configuration procedure).

At <NUM>, the base station <NUM>-c may determine a DRX configuration for the UE <NUM>-c. In some cases, the base station <NUM>-c may determine the DRX configuration to provide ON-durations at the UE <NUM>-c that correspond with the determined traffic periodicity, which may reduce power consumption at the UE <NUM>-c. At <NUM>, the base station <NUM>-c may transmit DRX configuration information to the UE <NUM>-c. In some cases, the DRX configuration may be provided in RRC signaling. In some cases, as part of the connection establishment, the UE <NUM>-c may indicate a capability for DRX configurations, and the base station <NUM>-c may enable this capability with the DRX configuration information. Additionally or alternatively, all or part of the DRX configuration information may be provided in DCI or in one or more MAC-CEs.

At <NUM>, the UE <NUM>-c may determine the DRX configuration. In some cases, the UE <NUM>-c may determine the DRX configuration based on RRC signaling from the base station <NUM>-c. At <NUM>, the base station <NUM>-c may transmit periodic reference signals (e.g., SSB, TRS, CSI-RS transmissions, or combinations thereof), and the UE <NUM>-c may monitor for one or more of the periodic reference signals. At <NUM>, the UE <NUM>-c may perform reference signal measurements and update one or more tracking loops, and initiate DRX procedures based on the DRX configuration. Such DRX procedures may include the UE <NUM>-c transitioning to a sleep mode between ON-durations, and transitioning to an awake mode to monitor for downlink transmissions from the base station <NUM>-c during ON-durations.

At <NUM>, the UE <NUM>-c may detect an uplink data arrival. In some cases, the uplink data arrival may be indicated by the presence of data in an uplink transmit buffer of the UE <NUM>-c. For example, an application running at an application processor of the UE <NUM>-a, while the UE <NUM>-c is in a DRX sleep mode, may generate uplink data that is to be transmitted to the base station <NUM>-c. The arrival of the uplink data may cause the UE <NUM>-c to transition out of the sleep mode and into an awake state for transmission of a request to obtain resources for transmission of the uplink data.

At <NUM>, the UE <NUM>-c may determine that a time threshold since the prior reference signal measurement or tracking loop update has elapsed. In some cases, such a determination may be made based on a timer that is started at each tracking loop update. In some cases, a time of a prior reference signal measurement or tracking loop update may be recorded and compared to a subsequent time associated with the uplink data arrival or expected transmission time of the uplink request to determine if the time threshold has elapsed.

At <NUM>, based on the determination that the time threshold has elapsed, the UE <NUM>-c may wait for a best reference signal transmission from the base station <NUM>-c. At <NUM>, the base station <NUM>-c may transmit the subsequent reference signal (e.g., SSB/TRS), which may be received at the UE <NUM>-c.

At <NUM>, the UE <NUM>-c may perform reference signal measurements and determine one or more uplink/downlink transmission/reception parameters based on the reference signal measurements. At <NUM>, the UE <NUM>-c may transmit an uplink request, such as an SR or RACH transmission to the base station <NUM>-c.

<FIG> shows a block diagram <NUM> of a device <NUM> that supports DRX wakeup techniques in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a UE <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communications manager <NUM>, and a transmitter <NUM>. The device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The receiver <NUM> may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to DRX wakeup techniques, etc.). Information may be passed on to other components of the device <NUM>. The receiver <NUM> may be an example of aspects of the transceiver <NUM> described with reference to <FIG>. The receiver <NUM> may utilize a single antenna or a set of antennas.

The communications manager <NUM> may determine a first set of parameters for wireless communications with a base station based on a first reference signal. In some cases, the first reference signal may be received from the base station and may be associated with a first time. The communications manager <NUM> may transition into a sleep mode of a DRX cycle, where the DRX cycle includes an ON-duration during which the UE is to wake up from the sleep mode to monitor for transmissions from the base station, and where the UE transitions to the sleep mode after the ON-duration. In some examples, the communications manager <NUM> may transition into the sleep mode after the first time. The communications manager <NUM> may identify, while in the sleep mode, that uplink data is present for transmission from the UE. In some cases, the identifying may be associated with a second time. In some examples, the communications manager <NUM> may determine an elapsed time between the first time and the second time. The communications manager <NUM> may transmit a request to the base station for uplink resources for transmission of the uplink data, where the request is transmitted before receiving a subsequent reference signal. In some cases, the communications manager <NUM> may transmit the request based on the elapsed time being less than a threshold value. In some cases, the subsequent reference signal may be received from the base station. The communications manager <NUM> may be an example of aspects of the communications manager <NUM> described herein.

If implemented in code executed by a processor, the functions of the communications manager <NUM>, or its sub-components may be executed by a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in the present disclosure.

The actions performed by the communications manager <NUM> as described herein may be implemented to realize one or more potential advantages. For example, transmitting a request to the base station for uplink resources for transmission of the uplink data before receiving a subsequent reference signal may allow the UE to decrease latency of communications between the UE and the base station. In some examples, transmitting the request to the base station before receiving the subsequent reference signal may further potentially reduce power consumption by decreasing the time a UE waits before transmitting uplink data.

A processor of the device <NUM> (e.g., a processor controlling the receiver <NUM>, the communications manager <NUM>, the transmitter <NUM>, or a combination thereof) may reduce latency associated with transmitting uplink data by performing an unscheduled wakeup procedure. For example, by transmitting the request to the base station before receiving the subsequent reference signal, the device <NUM> may reduce processing overhead (e.g., time or some other overhead) associated with transmitting uplink data. Additionally or alternatively, the processor may provide for relatively low power consumption at the UE (e.g., by decreasing the time a UE waits before transmitting uplink data.

<FIG> shows a block diagram <NUM> of a device <NUM> that supports DRX wakeup techniques in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a device <NUM>, or a UE <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communications manager <NUM>, and a transmitter <NUM>. The device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The communications manager <NUM> may be an example of aspects of the communications manager <NUM> as described herein. The communications manager <NUM> may include a loop update manager <NUM>, a DRX manager <NUM>, an uplink data identification component <NUM>, a DRX timer <NUM>, and an uplink transmission manager <NUM>. The communications manager <NUM> may be an example of aspects of the communications manager <NUM> described herein.

The loop update manager <NUM> may determine a first set of parameters for wireless communications with a base station based on a first reference signal. In some cases, the first reference signal may be received from the base station and may be associated with a first time.

The DRX manager <NUM> may transition into a sleep mode of a DRX cycle, where the DRX cycle includes an ON-duration during which the UE is to wake up from the sleep mode to monitor for transmissions from the base station, and where the UE transitions to the sleep mode after the ON-duration. In some cases, the DRX manager <NUM> may transition into the sleep mode after the first time.

The uplink data identification component <NUM> may identify, while in the sleep mode, that uplink data is present for transmission from the UE. In some cases, the identifying may be associated with a second time.

The DRX timer <NUM> may determine an elapsed time between the first time and the second time.

The uplink transmission manager <NUM> may transmit a request to the base station for uplink resources for transmission of the uplink data, where the request is transmitted before receiving a subsequent reference signal. In some cases, the uplink transmission manager <NUM> may transmit the request based on the elapsed time being less than a threshold value. In some cases, the subsequent reference signal may be received from the base station.

<FIG> shows a block diagram <NUM> of a communications manager <NUM> that supports DRX wakeup techniques in accordance with aspects of the present disclosure. The communications manager <NUM> may be an example of aspects of a communications manager <NUM>, a communications manager <NUM>, or a communications manager <NUM> described herein. The communications manager <NUM> may include a loop update manager <NUM>, a DRX manager <NUM>, an uplink data identification component <NUM>, a DRX timer <NUM>, an uplink transmission manager <NUM>, and a reference signal manager <NUM>. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses).

The loop update manager <NUM> may determine a first set of parameters for wireless communications with a base station based on a first reference signal. In some cases, the first reference signal may be received from the base station and may be associated with a first time. In some examples, the loop update manager <NUM> may determine a second set of parameters for wireless communications with the base station based on a subsequent reference signal received from the base station. In some cases, the first set of parameters includes one or more timing parameters, gain control parameters, frequency tracking parameters, power parameters, or any combinations thereof. In some cases, the UE updates one or more tracking loops based on the first set of parameters.

The DRX timer <NUM> may determine an elapsed time between the first time and the second time. In some examples, the DRX timer <NUM> may determine that the elapsed time exceeds or does not exceed the threshold value. In some cases, the threshold value is a predetermined time value. In some examples, the threshold value is based on the elapsed time. In some cases, the threshold value is based on one or more UE operating conditions. In some cases, the one or more UE operating conditions include a temperature of RF communications components at the UE, a rate of change of one or more of the first set of parameters across two or more tracking loops, a rate of change of a distance between the UE and the base station, or any combinations thereof. In some cases, the threshold value is selected to provide a timing error of a frequency tracking loop that is within a specified maximum timing error. In some examples, the DRX timer <NUM> may determine a maximum timing error of a frequency tracking loop and select the threshold value based on the maximum timing error.

The uplink transmission manager <NUM> may transmit, based on the elapsed time being less than a threshold value, a request to the base station for uplink resources for transmission of the uplink data, where the request is transmitted before receiving a subsequent reference signal from the base station. In some examples, the uplink transmission manager <NUM> may transmit, based on the elapsed time exceeding the threshold value, the request to the base station for uplink resources for transmission of the uplink data after determining a second set of parameters.

In some examples, the uplink transmission manager <NUM> may receive, from the base station, an uplink grant for the transmission of the uplink data. In some examples, the uplink transmission manager <NUM> may transmit at least a portion of the uplink data to the base station based on the uplink grant.

In some cases, the request to the base station is transmitted using one or more of random access channel resources or physical uplink control channel resources allocated for scheduling request transmissions.

The reference signal manager <NUM> may monitor, before or after transmitting the request to the base station, for the subsequent reference signal from the base station. In some cases, the first reference signal and the subsequent reference signal from the base station include one or more of a synchronization signal or a tracking reference signal. In some cases, the first reference signal and the subsequent reference signal are transmitted in synchronization signal block (SSB) transmissions or tracking reference signal (TRS) transmissions of the base station, and where the elapsed time is measured from a receipt of a SSB or TRS used to update the first set of parameters.

<FIG> shows a diagram of a system <NUM> including a device <NUM> that supports DRX wakeup techniques in accordance with aspects of the present disclosure. The device <NUM> may be an example of or include the components of device <NUM>, device <NUM>, or a UE <NUM> as described herein. The device <NUM> may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including a communications manager <NUM>, an I/O controller <NUM>, a transceiver <NUM>, an antenna <NUM>, memory <NUM>, and a processor <NUM>. These components may be in electronic communication via one or more buses (e.g., bus <NUM>).

The communications manager <NUM> may determine a first set of parameters for wireless communications with a base station based on a first reference signal received from the base station that is associated with a first time, transition, after the first time, into a sleep mode of a DRX cycle, where the DRX cycle includes an ON-duration during which the UE is to wake up from the sleep mode to monitor for transmissions from the base station, and where the UE transitions to the sleep mode after the ON-duration, identify, while in the sleep mode, that uplink data is present for transmission from the UE, the identifying associated with a second time, determine an elapsed time between the first time and the second time, and transmit, based on the elapsed time being less than a threshold value, a request to the base station for uplink resources for transmission of the uplink data, where the request is transmitted before receiving a subsequent reference signal from the base station.

The memory <NUM> may include RAM and ROM.

The processor <NUM> may include an intelligent hardware device, (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, the processor <NUM> may be configured to operate a memory array using a memory controller. In other cases, a memory controller may be integrated into the processor <NUM>. The processor <NUM> may be configured to execute computer-readable instructions stored in a memory (e.g., the memory <NUM>) to cause the device <NUM> to perform various functions (e.g., functions or tasks supporting DRX wakeup techniques).

<FIG> shows a block diagram <NUM> of a device <NUM> that supports DRX wakeup techniques in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a base station <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communications manager <NUM>, and a transmitter <NUM>. The device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The communications manager <NUM> may configure a first UE with a DRX configuration that is based on a DRX cycle that includes an ON-duration during which the UE is to wake up from a sleep mode to monitor for transmissions from the base station, discontinue the DRX configuration of the first UE, and receive, prior to an expected ON-duration, an uplink transmission from the first UE that indicates the UE has uplink data for transmission. The communications manager <NUM> may be an example of aspects of the communications manager <NUM> described herein.

<FIG> shows a block diagram <NUM> of a device <NUM> that supports DRX wakeup techniques in accordance with aspects of the present disclosure. The device <NUM> may be an example of aspects of a device <NUM>, or a base station <NUM> as described herein. The device <NUM> may include a receiver <NUM>, a communications manager <NUM>, and a transmitter <NUM>. The device <NUM> may also include a processor. Each of these components may be in communication with one another (e.g., via one or more buses).

The communications manager <NUM> may be an example of aspects of the communications manager <NUM> as described herein. The communications manager <NUM> may include a DRX manager <NUM> and an uplink transmission manager <NUM>. The communications manager <NUM> may be an example of aspects of the communications manager <NUM> described herein.

The DRX manager <NUM> may configure a first UE with a DRX configuration that is based on a DRX cycle that includes an ON-duration during which the UE is to wake up from a sleep mode to monitor for transmissions from the base station and discontinue the DRX configuration of the first UE.

The uplink transmission manager <NUM> may receive, prior to an expected ON-duration, an uplink transmission from the first UE that indicates the UE has uplink data for transmission.

<FIG> shows a block diagram <NUM> of a communications manager <NUM> that supports DRX wakeup techniques in accordance with aspects of the present disclosure. The communications manager <NUM> may be an example of aspects of a communications manager <NUM>, a communications manager <NUM>, or a communications manager <NUM> described herein. The communications manager <NUM> may include a DRX manager <NUM> and an uplink transmission manager <NUM>. Each of these modules may communicate, directly or indirectly, with one another (e.g., via one or more buses).

The DRX manager <NUM> may configure a first UE with a DRX configuration that is based on a DRX cycle that includes an ON-duration during which the UE is to wake up from a sleep mode to monitor for transmissions from the base station. In some examples, the DRX manager <NUM> may discontinue the DRX configuration of the first UE. The uplink transmission manager <NUM> may receive, prior to an expected ON-duration, an uplink transmission from the first UE that indicates the UE has uplink data for transmission.

<FIG> shows a diagram of a system <NUM> including a device <NUM> that supports DRX wakeup techniques in accordance with aspects of the present disclosure. The device <NUM> may be an example of or include the components of device <NUM>, device <NUM>, or a base station <NUM> as described herein. The device <NUM> may include components for bi-directional voice and data communications including components for transmitting and receiving communications, including a communications manager <NUM>, a network communications manager <NUM>, a transceiver <NUM>, an antenna <NUM>, memory <NUM>, a processor <NUM>, and an inter-station communications manager <NUM>. These components may be in electronic communication via one or more buses (e.g., bus <NUM>).

The communications manager <NUM> may configure a first UE with a DRX configuration that is based on a DRX cycle that includes an ON-duration during which the UE is to wake up from a sleep mode to monitor for transmissions from the base station, discontinue the DRX configuration of the first UE, and receive, prior to an expected ON-duration, an uplink transmission from the first UE that indicates the UE has uplink data for transmission.

The processor <NUM> may include an intelligent hardware device, (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, the processor <NUM> may be configured to operate a memory array using a memory controller. In some cases, a memory controller may be integrated into processor <NUM>. The processor <NUM> may be configured to execute computer-readable instructions stored in a memory (e.g., the memory <NUM>) to cause the device <NUM> to perform various functions (e.g., functions or tasks supporting DRX wakeup techniques).

<FIG> shows a flowchart illustrating a method <NUM> that supports DRX wakeup techniques in accordance with aspects of the present disclosure. The operations of method <NUM> may be implemented by a UE <NUM> or its components as described herein. For example, the operations of method <NUM> may be performed by a communications manager as described with reference to <FIG>. In some examples, a UE may execute a set of instructions to control the functional elements of the UE to perform the functions described below. Additionally or alternatively, a UE may perform aspects of the functions described below using special-purpose hardware.

At <NUM>, the UE may determine a first set of parameters for wireless communications with a base station based on a first reference signal. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a loop update manager as described with reference to <FIG>.

At <NUM>, the UE may transition into a sleep mode of a DRX cycle, where the DRX cycle includes an ON-duration during which the UE is to wake up from the sleep mode to monitor for transmissions from the base station, and where the UE transitions to the sleep mode after the ON-duration. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a DRX manager as described with reference to <FIG>.

At <NUM>, the UE may identify, while in the sleep mode, that uplink data is present for transmission from the UE. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by an uplink data identification component as described with reference to <FIG>.

At <NUM>, the UE may transmit a request to the base station for uplink resources for transmission of the uplink data, where the request is transmitted before receiving a subsequent reference signal. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by an uplink transmission manager as described with reference to <FIG>.

At <NUM>, the UE may monitor, after transmitting the request to the base station, for the subsequent reference signal. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a reference signal manager as described with reference to <FIG>.

At <NUM>, the UE may determine a second set of parameters for wireless communications with the base station based on the subsequent reference signal. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a loop update manager as described with reference to <FIG>.

At <NUM>, the UE may receive, from the base station, an uplink grant for the transmission of the uplink data. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by an uplink transmission manager as described with reference to <FIG>.

At <NUM>, the UE may transmit at least a portion of the uplink data to the base station based on the uplink grant. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by an uplink transmission manager as described with reference to <FIG>.

At <NUM>, the UE may determine a first time associated with the first reference signal and a second time associated with the identifying. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a DRX timer as described with reference to <FIG>.

At <NUM>, the UE may determine an elapsed time between the first time and the second time that exceeds a threshold value. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a DRX timer as described with reference to <FIG>.

At <NUM>, the UE may monitor for a subsequent reference signal. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by a reference signal manager as described with reference to <FIG>.

At <NUM>, the UE may transmit, based on the elapsed time exceeding the threshold value, the request to the base station for uplink resources for transmission of the uplink data after determining the second set of parameters. The operations of <NUM> may be performed according to the methods described herein. In some examples, aspects of the operations of <NUM> may be performed by an uplink transmission manager as described with reference to <FIG>.

Other examples and implementations are within the scope of the present disclosure.

By way of example, and not limitation, non-transitory computer-readable media may include random-access memory (RAM), read-only memory (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.

Claim 1:
A method for wireless communications at a user equipment, UE, (<NUM>), the method comprising:
receiving, from a base station (<NUM>), a first reference signal (<NUM>-a) associated with a first time;
transitioning into a sleep mode (<NUM>) of a discontinuous reception cycle, wherein the discontinuous reception cycle includes an ON-duration (<NUM>) during which the UE (<NUM>) is to wake up from the sleep mode (<NUM>) to monitor for transmissions from the base station (<NUM>), and wherein the UE (<NUM>) transitions to the sleep mode (<NUM>) after the ON-duration (<NUM>);
identifying, while in the sleep mode (<NUM>), that uplink data (<NUM>) is present for transmission from the UE (<NUM>), wherein the identifying is associated with a second time;
determining an elapsed time between the first time and the second time; and
transmitting a request (<NUM>) to the base station (<NUM>) for uplink resources for transmission of the uplink data (<NUM>), wherein the request (<NUM>) is transmitted before receiving a subsequent reference signal (<NUM>-b) and based at least in part on the elapsed time being less than a threshold value (<NUM>).