Patent Description:
Aspects of the present disclosure relate generally to wireless communication networks, and more particularly, to various schemes for recovery of reference signals (RSs) from dynamic multiplexing of ultra-reliable-low-latency communications (URLLC) and enhanced mobile broadband (eMBB).

For example, a fifth generation (<NUM>) wireless communications technology (which can be referred to as new radio (NR)) is envisaged to expand and support diverse usage scenarios and applications with respect to current mobile network generations. In an aspect, <NUM> communications technology can include: enhanced mobile broadband addressing human-centric use cases for access to multimedia content, services and data; URLLC with certain specifications for latency and reliability; and massive machine type communications, which can allow a very large number of connected devices and transmission of a relatively low volume of non-delay-sensitive information. As the demand for mobile broadband access continues to increase, however, further improvements in NR communications technology and beyond may be desired.

For example, for NR communications technology and beyond, current downlink dynamic multiplexing of URLLC/eMBB may not provide a desired level of reference signal (RS) recovery for efficient operation. Thus, improvements in wireless communication operations may be desired. <NPL>), discusses OMRS Collision Avoidance for multiplexing of eMBB and URLLC. <NPL>), provides a discussion on multiplexing of eMBB and URLLC
<CIT> is prior art according to Article <NUM>(<NUM>) EPC and describes resources being allocated for URLLC data transmission in a manner that minimally impacts eMBB data transmissions.

Various aspects are described for schemes that address the potential puncturing of important reference signals (RSs) for eMBB applications, such as demodulation reference signal (DMRS), channel state information reference signal (CSIRS), and tracking reference signal. The schemes can be used for recovery of eMBB's RS puncturing from dynamic multiplexing of URLLC and eMBB. The schemes may modify an existing RS pattern before puncturing occurs to reduce or minimize the effects of puncturing on the RS symbols within the eMBB traffic. For example, the schemes may modify the existing RS pattern configured for the eMBB traffic before puncturing occurs in response to a presence of the URLLC traffic. The schemes include an over-provisioning scheme. In addition, option not to use (e.g., disable) time-domain orthogonal cover code (TD-OCC) for the RSs.

Additionally, the term "component" as used herein may be one of the parts that make up a system, may be hardware, firmware, and/or software stored on a computer-readable medium, and may be divided into other components.

The present disclosure generally relates to various schemes for recovery of RS from dynamic multiplexing of ultra-reliable-low-latency communications (URLLC) and enhanced mobile broadband (eMBB). Various aspects are described for schemes that address the potential puncturing of important RSs for eMBB applications, such as demodulation reference signal (DMRS), channel state information reference signal (CSIRS), and tracking reference signal (CSIRS for tracking). The schemes can be used for recovery of eMBB's RS puncturing from dynamic multiplexing of URLLC and eMBB. The schemes can include one or more of an indication-based dynamic RS pattern scheme, a block-based scheme, or an over-provisioning scheme. In addition, there can be an option not to use (e.g., disable) time-domain orthogonal cover code (TD-OCC) for the RSs.

Additional features of the present aspects are described in more detail below with respect to <FIG>.

It should be noted that the techniques described herein may be used for various wireless communication networks such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and other systems. The terms "system" and "network" are often used interchangeably. IS-<NUM> Releases <NUM> and A are commonly referred to as CDMA2000 1X, 1X, etc. IS-<NUM> (TIA-<NUM>) is commonly referred to as CDMA2000 1xEV-DO, High Rate Packet Data (HRPD), etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. An OFDMA system may implement a radio technology such as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA), IEEE <NUM> (Wi-Fi), IEEE <NUM> (WiMAX), IEEE <NUM>, Flash-OFDM™, etc. UTRA and E-UTRA are part of Universal Mobile Telecommunication System (UMTS). 3GPP Long Term Evolution (LTE) and LTE-Advanced (LTE-A) are new releases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and GSM are described in documents from an organization named "3rd Generation Partnership Project" (3GPP). The techniques described herein may be used for the systems and radio technologies mentioned above as well as other systems and radio technologies, including cellular (e.g., LTE) communications over a shared radio frequency spectrum band. The description below, however, describes an LTE/LTE-A system for purposes of example, and LTE terminology is used in much of the description below, although the techniques are applicable beyond LTE/LTE-A applications (e.g., to <NUM> networks or other next generation communication systems).

Referring to <FIG>, in accordance with various aspects of the present disclosure, an example wireless communication network <NUM> includes at least one UE <NUM> with a modem <NUM> having a recovery component <NUM> that handles various aspects of processing potential puncturing of important reference signals (RSs) for eMBB applications for situations in which there is dynamic multiplexing of URLLC/eMBB communications in downlink transmissions, including receiving and processing indications associated with a scheme used to address the potential RS puncturing. Further, wireless communication network <NUM> includes at least one base station <NUM> with a modem <NUM> having a recovery component <NUM> that handles various aspects of processing potential puncturing of important reference signals (RSs) for eMBB applications for situations in which there is dynamic multiplexing of URLLC/eMBB communications in downlink transmissions, including generating and transmitting indications associated with a scheme used to address the potential RS puncturing.

The wireless communication network <NUM> may include one or more base stations <NUM>, one or more UEs <NUM>, and a core network <NUM>. The core network <NUM> may provide user authentication, access authorization, tracking, internet protocol (IP) connectivity, and other access, routing, or mobility functions. The base stations <NUM> may interface with the core network <NUM> through backhaul links <NUM> (e.g., S1, etc.). The base stations <NUM> may perform radio configuration and scheduling for communication with the UEs <NUM>, or may operate under the control of a base station controller (not shown). In various examples, the base stations <NUM> may communicate, either directly or indirectly (e.g., through core network <NUM>), with one another over backhaul links <NUM> (e.g., X1, etc.), which may be wired or wireless communication links.

The base stations <NUM> may wirelessly communicate with the UEs <NUM> via one or more base station antennas. In some examples, base stations <NUM> may be referred to as a base transceiver station, a radio base station, an access point, an access node, a radio transceiver, a NodeB, eNodeB (eNB), gNB, Home NodeB, a Home eNodeB, a relay, or some other suitable terminology. The geographic coverage area <NUM> for a base station <NUM> may be divided into sectors or cells making up only a portion of the coverage area (not shown). The wireless communication network <NUM> may include base stations <NUM> of different types (e.g., macro base stations or small cell base stations, described below). Additionally, the plurality of base stations <NUM> may operate according to different ones of a plurality of communication technologies (e.g., <NUM> (New Radio or "NR"), fourth generation (<NUM>)/LTE, <NUM>, Wi-Fi, Bluetooth, etc.), and thus there may be overlapping geographic coverage areas <NUM> for different communication technologies.

In some examples, the wireless communication network <NUM> may be or include one or any combination of communication technologies, including a NR or <NUM> technology, a Long Term Evolution (LTE) or LTE-Advanced (LTE-A) or MuLTEfire technology, a Wi-Fi technology, a Bluetooth technology, or any other long or short range wireless communication technology. In LTE/LTE-A/MuLTEfire networks, the term evolved node B (eNB) may be generally used to describe the base stations <NUM>, while the term UE may be generally used to describe the UEs <NUM>. The wireless communication network <NUM> may be a heterogeneous technology network in which different types of eNBs provide coverage for various geographical regions. For example, each eNB or base station <NUM> may provide communication coverage for a macro cell, a small cell, or other types of cell. The term "cell" is a 3GPP term that can be used to describe a base station, a carrier or component carrier associated with a base station, or a coverage area (e.g., sector, etc.) of a carrier or base station, depending on context.

A macro cell may generally cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs <NUM> with service subscriptions with the network provider.

A small cell may include a relative lower transmit-powered base station, as compared with a macro cell, that may operate in the same or different frequency bands (e.g., licensed, unlicensed, etc.) as macro cells. A femto cell may also cover a small geographic area (e.g., a home) and may provide restricted access and/or unrestricted access by UEs <NUM> having an association with the femto cell (e.g., in the restricted access case, UEs <NUM> in a closed subscriber group (CSG) of the base station <NUM>, which may include UEs <NUM> for users in the home, and the like).

The communication networks that may accommodate some of the various disclosed examples may be packet-based networks that operate according to a layered protocol stack and data in the user plane may be based on the IP. A user plane protocol stack (e.g., packet data convergence protocol (PDCP), radio link control (RLC), MAC, etc.), may perform packet segmentation and reassembly to communicate over logical channels. For example, a MAC layer may perform priority handling and multiplexing of logical channels into transport channels. The MAC layer may also use hybrid automatic repeat/request (HARQ) to provide retransmission at the MAC layer to improve link efficiency. In the control plane, the RRC protocol layer may provide establishment, configuration, and maintenance of an RRC connection between a UE <NUM> and the base stations <NUM>. The RRC protocol layer may also be used for core network <NUM> support of radio bearers for the user plane data. At the physical (PHY) layer, the transport channels may be mapped to physical channels.

The UEs <NUM> may be dispersed throughout the wireless communication network <NUM>, and each UE <NUM> may be stationary or mobile. A UE <NUM> may also include or be referred to by those skilled in the art as a mobile station, a subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a mobile device, a wireless device, a wireless communications device, a remote device, a mobile subscriber station, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, a user agent, a mobile client, a client, or some other suitable terminology. A UE <NUM> may be a cellular phone, a smart phone, a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a tablet computer, a laptop computer, a cordless phone, a smart watch, a wireless local loop (WLL) station, an entertainment device, a vehicular component, a customer premises equipment (CPE), or any device capable of communicating in wireless communication network <NUM>. Additionally, a UE <NUM> may be Internet of Things (IoT) and/or machine-to-machine (M2M) type of device, e.g., a low power, low data rate (relative to a wireless phone, for example) type of device, that may in some aspects communicate infrequently with wireless communication network <NUM> or other UEs. A UE <NUM> may be able to communicate with various types of base stations <NUM> and network equipment including macro eNBs, small cell eNBs, macro gNBs, small cell gNBs, relay base stations, and the like.

UE <NUM> may be configured to establish one or more wireless communication links <NUM> with one or more base stations <NUM>. The wireless communication links <NUM> shown in wireless communication network <NUM> may carry uplink (UL) transmissions from a UE <NUM> to a base station <NUM>, or downlink (DL) transmissions, from a base station <NUM> to a UE <NUM>. The downlink transmissions may also be called forward link transmissions while the uplink transmissions may also be called reverse link transmissions. Each wireless communication link <NUM> may include one or more carriers, where each carrier may be a signal made up of multiple sub-carriers (e.g., waveform signals of different frequencies) modulated according to the various radio technologies described above. Each modulated signal may be sent on a different sub-carrier and may carry control information (e.g., reference signals, control channels, etc.), overhead information, user data, etc. In an aspect, the wireless communication links <NUM> may transmit bidirectional communications using frequency division duplex (FDD) (e.g., using paired spectrum resources) or time division duplex (TDD) operation (e.g., using unpaired spectrum resources). Frame structures may be defined for FDD (e.g., frame structure type <NUM>) and TDD (e.g., frame structure type <NUM>). Moreover, in some aspects, the wireless communication links <NUM> may represent one or more broadcast channels.

In some aspects of the wireless communication network <NUM>, base stations <NUM> or UEs <NUM> may include multiple antennas for employing antenna diversity schemes to improve communication quality and reliability between base stations <NUM> and UEs <NUM>. Additionally or alternatively, base stations <NUM> or UEs <NUM> may employ multiple input multiple output (MIMO) techniques that may take advantage of multi-path environments to transmit multiple spatial layers carrying the same or different coded data.

Wireless communication network <NUM> may support operation on multiple cells or carriers, a feature which may be referred to as carrier aggregation (CA) or multi-carrier operation. A carrier may also be referred to as a component carrier (CC), a layer, a channel, etc. The terms "carrier," "component carrier," "cell," and "channel" may be used interchangeably herein. A UE <NUM> may be configured with multiple downlink CCs and one or more uplink CCs for carrier aggregation. The base stations <NUM> and UEs <NUM> may use spectrum up to Y MHz (e.g., Y = <NUM>, <NUM>, <NUM>, or <NUM>) bandwidth per carrier allocated in a carrier aggregation of up to a total of Yx MHz (x = number of component carriers) used for transmission in each direction. Allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or less carriers may be allocated for DL than for UL).

The wireless communication network <NUM> may further include base stations <NUM> operating according to Wi-Fi technology, e.g., Wi-Fi access points, in communication with UEs <NUM> operating according to Wi-Fi technology, e.g., Wi-Fi stations (STAs) via communication links in an unlicensed frequency spectrum (e.g., <NUM>). When communicating in an unlicensed frequency spectrum, the STAs and AP may perform a clear channel assessment (CCA) or listen before talk (LBT) procedure prior to communicating in order to determine whether the channel is available.

Additionally, one or more of base stations <NUM> and/or UEs <NUM> may operate according to a NR or <NUM> technology referred to as millimeter wave (mmW or mmwave) technology. For example, mmW technology includes transmissions in mmW frequencies and/or near mmW frequencies. Extremely high frequency (EHF) is part of the radio frequency (RF) in the electromagnetic spectrum. For example, the super high frequency (SHF) band extends between <NUM> and <NUM>, and may also be referred to as centimeter wave. Communications using the mmW and/or near mmW radio frequency band has extremely high path loss and a short range. As such, base stations <NUM> and/or UEs <NUM> operating according to the mmW technology may utilize beamforming in their transmissions to compensate for the extremely high path loss and short range.

Additional aspects are provided below regarding various schemes for recovering puncturing that may happen on any type of reference signal (RS) of eMBB, where the puncturing will happen from a URLLC transmission.

Referring to <FIG>, a diagram <NUM> is shown that illustrates examples of a mini-slot <NUM>, which can be the smallest scheduling unit for NR. Mini-slots are a methodology used to schedule low latency users (e.g., URLLC users) because they may only need a small amount of data and they may need it fast. The mini-slot <NUM> could have control at the beginning, and/or at the end, or no control at all. The mini-slot <NUM> could have a duration as small as <NUM> symbol (e.g., <NUM> OFDM symbol). The mini-slot can potentially have a pilot in the first symbol, and data in the remaining symbols. The mini-slot <NUM> can have a subcarrier spacing (SCS) or numerology different than the regular eMBB slot. For example, as illustrated in <FIG>, an eMBB slot <NUM> can have an SCS of f0, which may be, for example, <NUM>. The eMBB slot <NUM> can have <NUM> OFDM symbols. As illustrated, the mini-slot <NUM> may have a length of <NUM> eMBB OFDM symbols. The mini-slot <NUM> may have an SCS of either <NUM> (<NUM> symbols) or <NUM> (<NUM> symbols). The DMRS of the mini-slot may be generally positioned at the beginning. In addition, because scalable numerology is supported in <NUM>, a change in symbol duration can occur with a change in SCS.

Referring to <FIG>, a diagram <NUM> is shown in connection with the efficient support of URLLC and eMBB services on shared resources. Dynamic resource sharing is one very important design issue for NR. One way to support URLLC is to enable dynamic multiplexing with eMBB. The sporadic URLLC transmission bursts may preempt parts of the already scheduled eMBB transmissions to UEs. In the downlink (DL), this can be accomplished by using slots <NUM> for the eMBB transmissions and mini-slots <NUM> for URLLC transmissions. One example is illustrated in <FIG>. In that example, there are <NUM> aggregated <NUM>-symbol slots <NUM> with SCS = <NUM> that are used to carry the eMBB transmissions and one <NUM>-symbol mini-slot <NUM> with the same SCS that is used for URLLC.

In <FIG>, eMBB users may use SLOT <NUM> and SLOT <NUM> and the eNB may determine that there is data for a URLLC transmission in one slot <NUM> that cannot wait until a next opportunity (e.g., a next slot). Thus, the eNB schedules the mini-slot <NUM> for URLLC such that the URLLC user gets the data it needs fast, that is, the eNB gives priority to the URLLC user even though the eMBB user was already scheduled to use those resources. The eMBB user takes a hit in performance as a result. Therefore, in an aspect, an indication to the eMBB user that the preemption/dynamic multiplexing/puncturing is taking place may allow the eMBB user to recover from that issue. There may be different times at which such an indication can be provided to the eMBB user.

Referring to <FIG>, a diagram <NUM> is shown describing aspects in connection with DL URLLC/eMBB dynamic multiplexing and indication design. In <FIG>, there is shown an indication-based multiplexing approach, which is beneficial for both URLLC and eMBB UEs at the cost of indicator overhead. The indication <NUM> shown is a current indication (current with respect to URLLC) that is transmitted on the indication channel <NUM> whenever puncturing by URLLC occurs. The indication channel <NUM> shown in <FIG> is frequency-division multiplexed (FDM) with the actual slot.

Referring to <FIG>, a diagram <NUM> is shown describing aspects in connection with DL lJRLLC/eMBB dynamic multiplexing and indication design. Like <FIG>, there is shown an indication-based multiplexing approach, which is beneficial for both URLLC and eMBB UEs at the cost of indicator overhead. The indication <NUM> shown is a post-indication for both URLLC and the eMBB. For example, the indication <NUM> may be transmitted in an eMBB slot subsequent to an eMBB slot in which the puncturing occurs.

Referring to <FIG>, a diagram <NUM> is shown describing aspects in connection with DL URLLC/eMBB dynamic multiplexing and indication design. Like <FIG> and <FIG>, there is shown an indication-based multiplexing approach, which is beneficial for both URLLC and eMBB UEs at the cost of indicator overhead. The indication <NUM> shown is a post-indication for the URLLC and current with respect to the eMBB. That is, the indication <NUM> may be transmitted within the eMBB slot that is punctured.

One of the issues with the puncturing or preemption described above is that the puncturing may occur when reference signals (RSs) are scheduled to be transmitted for the eMBB user. Referring to <FIG>, diagrams <NUM> and <NUM> are shown to describe URLLC puncturing of eMBB RSs. In these diagrams, URLLC transmission on the DL may puncture the RS of the eMBB UE. The RSs can be one or more of DMRS, CSIRS, tracking RS (CSI RS for tracking), or general RS. The tracking RS may be used for Doppler estimation and/or delay spread estimation. As shown in diagram <NUM>, a mini-slot control monitoring is done at several locations in the eMBB slots to see if an URLLC user is asking for the channel and therefore these locations will be associated with the use of a mini-slot for the URLLC user.

Some mini-slots may puncture data and not RSs. However, there could be the case that a mini-slot punctures RS symbols. If, for example, a DMRS is lost due to puncturing, channel estimation for the entire slot may be inaccurate and demodulation would result in the wrong data. Similarly, puncturing CSIRS symbols could result in bad or inaccurate CSI, and puncturing tracking RS symbols could result in incorrect delay spread, or Doppler spread calculations. The eMBB performance can be recovered by using any one of the solutions/schemes described below. These solutions/schemes can be used for any of the RSs described above.

Referring to <FIG>, a diagram <NUM> is shown in connection with an indication-based dynamic RS pattern scheme or solution that can be applied to address potential RS puncturing by URLLC/eMBB dynamic multiplexing. If RS has to be punctured, eNB (e.g., base station or gNB) can re-schedule the RS, even in the same slot. For example, the RS <NUM> can be moved to the next symbol or to a few symbols later in the slot, and the eNB can notify the eMBB UEs via current indication <NUM> or a post-indication as described above. In the scenario of a current indication <NUM>, the RS puncturing notification can be embedded inside the current indication.

In the example shown in diagram <NUM>, two symbols are punctured by URLLC. An additional RS <NUM> is sent (e.g., at symbol <NUM>) because URLLC punctured the previous RS <NUM> (e.g., at symbol <NUM>). This additional RS <NUM> is not scheduled if URLLC puncturing has not occurred. Moreover, the base station or gNB can embed inside the indication <NUM> that the UE is to expect a new RS. The location of the new RS in case of such notification can be pre-configured semi-statically, (with L2 (MAC CE) or L3 (RRC) signaling), or it can even be embedded inside the indication <NUM>.

When a current indication is used, the indication <NUM> provides information as to where the puncturing occurs, but there also needs to be some form of knowing where the additional RS <NUM> that is going to be sent will be in the slot. That information may have been configured already in a semi-static manner. For example, going back to the example in <FIG>, once the RS <NUM> in symbol <NUM> was punctured, the location for the additional RS <NUM> was configured to be symbol <NUM>. To take the example further, if the additional RS <NUM> in symbol <NUM> were also to be punctured, there may be a configured subsequent symbol (e.g., symbol <NUM>, <NUM>, or <NUM>) where an additional RS would be scheduled. This changing of the RS positions may be referred to a dynamic RS pattern given that the locations of the RS symbols may change dynamically based on where the URLLC transmission takes place within a slot.

Referring to <FIG>, a diagram <NUM> is shown in connection with an indication-based dynamic RS pattern scheme or solution that can be applied to address potential RS puncturing by URLLC/eMBB dynamic multiplexing. In this example, the indication channel <NUM> is at the end of the slot and, consequently, a post-indication approach is being used. If RS <NUM> has to be punctured, NB (e.g., base station or gNB) can re-schedule the RS <NUM>. For example, the RS <NUM> can be moved to the next symbol or to a few symbols later in the slot as an additional RS <NUM>, and the eNB can notify the eMBB UEs via post indication.

In the example shown in diagram <NUM>, the additional RS <NUM> is sent because URLLC punctured the previous RS <NUM>. This additional RS <NUM>. is not scheduled if RS puncturing due to the URCCL transmission has not occurred. Since the UE is expecting the indication in the end of the slot, it is likely that the UE has not yet started the demodulation/decoding of data. When the UE receives the indication channel <NUM>, the UE sees that actually the first RS <NUM> has been corrupted and there is a new additional RS <NUM> scheduled. The UE has buffered the symbols, and can throw away the bad measurement(s) and repeat the channel estimation and data demodulation and decoding procedures with the uncorrupted additional RS <NUM>. Moreover, the base station <NUM> or gNB can embed inside the indication channel <NUM> that the UE has received an additional RS <NUM> in a new location, and that the previous RS <NUM> is corrupted.

Referring to <FIG>, a diagram <NUM> is shown in connection with a block-based scheme or solution that can be applied to address potential RS puncturing by URLLC/eMBB dynamic multiplexing. This scheme, as well as the scheme described below with respect to <FIG>, modify or change an existing RS pattern <NUM> to avoid, reduce, or minimize the effects of puncturing on RSs in the eMBB slot. For example, the block-based scheme may modify an existing RS pattern configured for the eMBB traffic before puncturing occurs in response to a presence of the URLLC traffic.

In this scheme, the gNB can spread the fixed RS symbols within a slot, then URLLC puncturing may only occur in gaps between RSs (e.g., in data symbols). It is very likely that one symbol delayed puncturing (RS symbol blocking) may not have much of an effect on URLLC performance, so a delay of one symbol for URLLC to avoid puncturing eMBB RS symbols can be tolerated. In this scheme, it is important to ensure that there are no time-domain consecutive RS symbols, to minimize the probability of long delay of URLLC.

The example modified RS pattern <NUM> shown in diagram <NUM> of <FIG> illustrates the different arrangement of RSs to allow for multiple symbols between RSs that can be used for URLLC transmissions. In this example modified RS pattern <NUM>, there can be mini-slots of two symbols (e.g., symbols <NUM> and <NUM>) and mini-slots of <NUM> symbols (e.g., symbols <NUM>, <NUM>, <NUM>) used without puncturing any of the RS symbols present. Further, since each of the RS is only one symbol long, the maximum delay in scheduling the URLLC transmission is one symbol.

The scheme described in connection with <FIG> can be assumed as the default scheme (in those instances when multiple schemes may be supported). The UE can safely use the RSs without worrying that any RS was punctured. No need of blindly figuring out whether an RS was punctured.

There may be some notification or pre-configuration indicating how the RS pattern is to change in the block-based scheme. For example, the base station <NUM> may transmit a notification to eMBB UEs when there is a lot of sporadic URLLC traffic. That is, when a number or frequency of URLLC traffic satisfies a threshold, the base station <NUM> may transmit a notification indicating that the existing RS pattern <NUM> is to be changed to the modified RS pattern <NUM>. This notification or pre-configuration can be made in a semi-static manner.

Referring to <FIG>, a diagram <NUM> is shown in connection with an over-provisioning scheme or solution that can be applied to address potential RS puncturing by URLLC/eMBB dynamic multiplexing. The over-provisioning scheme may modify an existing RS pattern configured for the eMBB traffic before puncturing occurs in response to a presence of the URLLC traffic.

In this scheme, the gNB can schedule more RS symbols than what is needed, assuming some probability of URLLC traffic needed to be transmitted and some probability of that URLLC traffic indeed puncturing at least one of the RS symbols. In this case, the gNB does not schedule more RSs depending on actual RS puncturing by the already transmitted URLLC traffic, but the gNB preemptively schedules the additional RSs. For example, the existing RS pattern <NUM> may include RS in two symbols (e.g., <NUM> and <NUM>). Based on a URLLC traffic pattern, the gNB may determine to change the RS pattern to the modified RS pattern <NUM>, which includes RS in four symbols (e.g., <NUM>, <NUM>, <NUM>, and <NUM>). The gNB can notify the UE that this scheme is chosen. For example, the base station <NUM> may transmit a notification to eMBB UEs when there is a lot of sporadic URLLC traffic. That is, when a number or frequency of URLLC traffic satisfies a threshold, the base station <NUM> may transmit a notification indicating that the existing RS pattern <NUM> is to be changed to the modified RS pattern <NUM>. The eMBB UEs might need to do some blind estimations to determine whether some of the RSs were corrupted.

Referring to <FIG>, a diagram <NUM> is shown in connection with the removal or disabling of time-domain orthogonal cover code (TD-OCC) for the RSs. There is an option to not use TD-OCC for RSs (even if they are consecutive). For CSIRS for example, a <NUM>-symbol CSIRS may be transmitted. In a first option, the <NUM> symbols may be spread apart, similar to the block-based scheme discussed with respect to <FIG>. In another option, the <NUM> symbols may remain consecutive but without TD-OCC. The TD-OCC may be removed because if TD-OCC is applied and one symbol is punctured, all four symbols may be punctured. The disabling of TD-OCC can be enabled when there is significant URLLC traffic (e.g., an amount or rate of URLLC traffic satisfies a threshold).

In other aspects, when dealing with DMRS, and the rank of the transmission is large, then the block-based scheme may be preferred. No DMRS should be punctured (even if there is retransmission (reTx)) because the DMRS are placed in an "optimal" arrangement in the slot. That is, a large or high rank transmission (e.g., high spectral efficiency slots) needs good channel quality and good channel estimation. Even if there is a DMRS reTx, the location of the retransmission might not be the best. For example, the original location of DMRS in the slot may have been selected to allow the UE to perform interpolation in order to obtain a good channel estimation.

Similarly, if a UE moves at a very high speed where the channel decorrelates very fast, the selected scheme may depend on the Doppler/mobility of the eMBB user (in which case already there is a need for many DMRS) and the over-provisioning scheme may not be applicable. In this case, the block-based scheme may again be preferred.

When multiple schemes are supported, it may be possible to switch between the schemes that are supported. For example, the gNB schedules an RS resource, and then, through L1 or L2 or L3 signaling, the gNB notifies the UE which scheme may be implemented as a scheme for recovery if puncturing of that specific RS resource is expected. For the same UE, for different RS resources, different schemes could be applied. For example, the DMRS resource may be dynamically re-scheduled based on an indication based dynamic RS pattern scheme, but the CSIRS resource can use the over-provisioning scheme.

The chosen scheme can be cell-specific/UE-specific/RS-resource-specific. For example, the scheme that is chosen can be the same for all the UEs in a cell, can be selected specifically for a UE based on certain conditions or criteria, or can be selected specifically for a type of RS resource.

Referring to <FIG>, one example of an implementation of UE <NUM> may include a variety of components, some of which have already been described above, but including components such as one or more processors <NUM> and memory <NUM> and transceiver <NUM> in communication via one or more buses <NUM>, which may operate in conjunction with modem <NUM> and recovery component <NUM> to enable one or more of the functions described herein related to schemes for recovery of RS from dynamic multiplexing of URLLC and eMBB. Further, the one or more processors <NUM>, modem <NUM>, memory <NUM>, transceiver <NUM>, RF front end <NUM> and one or more antennas <NUM>, may be configured to support voice and/or data calls (simultaneously or non-simultaneously) in one or more radio access technologies.

In an aspect, the one or more processors <NUM> can include a modem <NUM> that uses one or more modem processors. The various functions related to recovery component <NUM> may be included in modem <NUM> and/or processors <NUM> and, in an aspect, can be executed by a single processor, while in other aspects, different ones of the functions may be executed by a combination of two or more different processors. For example, in an aspect, the one or more processors <NUM> may include any one or any combination of a modem processor, or a baseband processor, or a digital signal processor, or a transmit processor, or a receiver processor, or a transceiver processor associated with transceiver <NUM>. In other aspects, some of the features of the one or more processors <NUM> and/or modem <NUM> associated with recovery component <NUM> may be performed by transceiver <NUM>.

Also, memory <NUM> may be configured to store data used herein and/or local versions of applications <NUM> or recovery component <NUM> and/or one or more of its subcomponents being executed by at least one processor <NUM>. Memory <NUM> can include any type of computer-readable medium usable by a computer or at least one processor <NUM>, such as random access memory (RAM), read only memory (ROM), tapes, magnetic discs, optical discs, volatile memory, non-volatile memory, and any combination thereof. In an aspect, for example, memory <NUM> may be a non-transitory computer-readable storage medium that stores one or more computer-executable codes defining recovery component <NUM> and/or one or more of its subcomponents, and/or data associated therewith, when UE <NUM> is operating at least one processor <NUM> to execute recovery component <NUM> and/or one or more of its subcomponents.

Receiver <NUM> may include hardware, firmware, and/or software code executable by a processor for receiving data, the code comprising instructions and being stored in a memory (e.g., computer-readable medium). Additionally, receiver <NUM> may process such received signals, and also may obtain measurements of the signals, such as, but not limited to, Ec/Io, SNR, RSRP, RSSI, etc. Transmitter <NUM> may include hardware, firmware, and/or software code executable by a processor for transmitting data, the code comprising instructions and being stored in a memory (e.g., computer-readable medium). A suitable example of transmitter <NUM> may include, but is not limited to, an RF transmitter.

Recovery component <NUM> can include one or more subcomponents to perform aspects of eMBB RS recovery from the perspective of a UE. For example, recovery component <NUM> can include a scheme identification <NUM> that can identify a supported scheme for handling recovery of eMBB's RS puncturing from dynamic multiplexing of URLLC and eMBB. The recovery component <NUM> can receive information or indications/notifications with information that can be used to identify or select a scheme. In this regard, the recovery component <NUM> can include an indication <NUM> that can receive, process, or otherwise handle different indications/notifications. For example, the indication <NUM> can process notifications used for semi-static pre-configuration, as well as current indications and post-indications as described above with respect to <FIG>, <FIG>, and <FIG>. Moreover, the indication <NUM> can process indications associated with the disabling or removal of TD-OCC. Scheme-related indications and TD-OCC-related indications can be provided separately or together.

The recovery component <NUM> can also include one or more subcomponents associated with different recovery schemes. For example, recovery component <NUM> can include an indication-based dynamic RS pattern scheme <NUM>, a block-based scheme <NUM>, and an over-provisioning RS scheme <NUM>. In some implementations, a subset of these subcomponents can be used. The recovery component <NUM> can also include a TF-OCC <NUM> subcomponent to handle the removal of TD-OCC for some RSs.

Referring to <FIG>, one example of an implementation of base station <NUM> may include a variety of components, some of which have already been described above, but including components such as one or more processors <NUM> and memory <NUM> and transceiver <NUM> in communication via one or more buses <NUM>, which may operate in conjunction with modem <NUM> and recovery component <NUM> to enable one or more of the functions described herein related to schemes for recovery of RS from dynamic multiplexing of URLLC and eMBB.

Recovery component <NUM> can include one or more subcomponents to perform aspects of eMBB RS recovery from the perspective of a base station. For example, recovery component <NUM> can include scheme identification <NUM> that can identify a supported scheme for handling recovery of eMBB's RS puncturing from dynamic multiplexing of URLLC and eMBB. The recovery component <NUM> can generate and transmit information or indications/notifications with information that can be used to identify or select a scheme. In this regard, the recovery component <NUM> can include an indication <NUM> that can generate, process, or otherwise handle different indications/notifications. For example, the indication <NUM> can provide notifications used for semi-static pre-configuration, as well as current indications and post-indications as described above with respect to <FIG>, <FIG>, and <FIG>. Moreover, the indication <NUM> can provide indications associated with the disabling or removalof TD-OCC. Scheme-related indications and TD-OCC-related indications can be provided separately or together.

The recovery component <NUM> can also include one or more subcomponents associated with different recovery schemes. For example, recovery component <NUM> can include an indication-based dynamic RS pattern scheme <NUM>, a block-based scheme <NUM>, and an over-provisioning RS scheme <NUM>. In some implementations, a subset of these subcomponents can be used. The recovery component <NUM> can also include a TD-OCC <NUM> subcomponent to handle the removal of TD-OCC for some RSs.

Referring to <FIG>, for example, a method <NUM> of wireless communication in operating base station <NUM> according to the above-described aspects is illustrated for handling recovery of eMBB's RS puncturing from dynamic multiplexing of URLLC and eMBB.

For example, at <NUM>, the method <NUM> includes identifying, at a base station, at least one scheme for handling puncturing of RS symbols in eMBB traffic by URLLC traffic. In an aspect, the scheme can be preemptive to handle potential puncturing events. That is, each of the at least one scheme_may modify an existing RS pattern before puncturing occurs to reduce or minimize the effects of puncturing on the RS symbols within the eMBB traffic. For instance, in an aspect, the base station <NUM> may execute the processor <NUM>, the modem <NUM>, and/or one or more subcomponents of the recovery component <NUM> (e.g., scheme identification <NUM>), as described herein.

At <NUM>, the method <NUM> includes performing, at the base station, the at least one scheme in connection with downlink transmission. For instance, in an aspect, the base station <NUM> may execute the processor <NUM>, the modem <NUM>, and/or one or more subcomponents of the recovery component <NUM>, as described herein.

In another aspect of the method <NUM>, the RS symbols in the eMBB traffic are associated with one or more of demodulation reference signal (DMRS), a channel state information reference signal (CSIRS), a tracking reference signal, or a general reference signal.

In another aspect of the method <NUM>, identifying the scheme includes, at <NUM>, selecting the at least one scheme from a plurality of schemes supported by the base station based on a pattern of the URLLC traffic. For example, the base station <NUM> includes support in the recovery component <NUM> for one or more schemes, including support provided by the indication-based dynamic RS pattern scheme <NUM>, the block-based scheme <NUM>, and the over-provisioning RS scheme <NUM>. The scheme identification <NUM> may select the at least one scheme based on a pattern of the URLLC traffic. For example, if a volume of URLLC traffic satisfies a threshold, the scheme identification <NUM> may select the block-based scheme <NUM> or the over-provisioning RS scheme <NUM>.

In another aspect of the method <NUM>, identifying the scheme can include, at <NUM>, identifying a block-based scheme in which RS symbols within a slot for the eMBB traffic are spread apart for potential puncturing by the URLLC traffic to occur on data symbols between the RS symbols (see e.g., <FIG>). For example, the scheme identification <NUM> may identify the block-based scheme <NUM>. In an aspect, the block-based scheme <NUM> can be identified or selected as the scheme when the eMBB traffic is a high rank transmission or when operating conditions involve high speed operations. In another aspect, the block-based scheme may include no time-domain consecutive RS symbols in the eMBB traffic.

In another aspect of the method <NUM>, identifying the scheme can include, at <NUM>, identifying an over-provisioning RS scheme in which additional RS symbols are preemptively scheduled by the base station within a slot for the eMBB traffic before URLLC traffic is scheduled within the slot (see e.g., <FIG>). For example, the scheme identification <NUM> may identify the over-provisioning RS scheme <NUM>.

In another aspect of the method <NUM>, at <NUM>, the method can further include disabling or removing the use of a time-domain orthogonal covered code (TD-OCC) in connection with the eMBB traffic, and at <NUM> transmitting an indication that the TD-OCC is disabled or removed (see e.g., <FIG>). For example, the TD-OCC <NUM> may disable or remove the use of TD-OCC in connection with the eMBB traffic, and transmit an indication <NUM> that the TD-OCC is disabled or removed.

In yet another aspect of the method <NUM>, identifying the scheme can include identifying one or more of a scheme specified for particular cell (e.g., cell-specific scheme), a scheme specified for a particular UE (e.g., a UE-specific scheme), or a scheme specified for a particular RS resource (e.g., an RS-source-specific scheme, where the RS source can be, for example, DMRS, CSIRS, tracking RS, and/or general RS).

Referring to <FIG>, for example, a method <NUM> of wireless communication in operating UE <NUM> according to the above-described aspects is illustrated for handling recovery of eMBB's RS puncturing from dynamic multiplexing of URLLC and eMBB.

For example, at <NUM>, the method <NUM> includes receiving, at a UE, an indication of at least one scheme for handling puncturing of RS symbols in eMBB traffic by URLLC traffic. The at least one scheme can be preemptive to handle potential puncturing events. That is, each of the at least one scheme may modify an existing RS pattern before puncturing occurs to reduce or minimize the effects of puncturing on the RS symbols within the eMBB traffic. For instance, in an aspect, the UE <NUM> may execute the processor <NUM>, the modem <NUM>, one or more subcomponents of the recovery component <NUM>, the transceiver <NUM>, and/or the RF front end <NUM>, as described herein.

At <NUM>, the method <NUM> includes performing, at the UE, the at least one scheme in connection with downlink transmission. For instance, in an aspect, the UE <NUM> may execute the processor <NUM>, the modem <NUM>, and/or one or more subcomponents of the recovery component <NUM>, as described herein.

In another aspect of the method <NUM>, the RS symbols in the eMBB traffic can be associated with one or more of a demodulation reference signal (DMRS), a channel state information reference signal (CSIRS), a tracking reference signal, or a general reference signal.

In another aspect of the method <NUM>, the indication can identify the scheme from a plurality of schemes supported by the UE. For example, the UE <NUM> includes support in the recovery component <NUM> for one or more schemes, including support provided by the indication-based dynamic RS pattern scheme <NUM>, the block-based scheme <NUM>, and the over-provisioning RS scheme <NUM>. In another aspect of the method <NUM>, the scheme can be an indication-based RS pattern scheme in which a pattern of RS symbols in a slot for the eMBB traffic is changed based at least in part on the URLLC traffic. The pattern of RS symbols can be changed based on a pre-configured pattern (see e.g., <FIG> and <FIG> where the location or pattern of RS symbols changes in response to potential puncturing by a URLLC mini-slot). In this case, performing the indication-based RS pattern scheme can include, at <NUM>, buffering the symbols in the slot for the eMBB traffic, and at <NUM>, demodulating data in the slot for the eMBB traffic based on the dynamically changed pattern of RS symbols.

In another aspect of the method <NUM>, the scheme can be a block-based scheme in which RS symbols within a slot for the eMBB traffic are spread apart for potential puncturing by the URLLC traffic to occur on data symbols between the RS symbols (see e.g., <FIG>). For example, the scheme identification <NUM> may identify or select the block-based scheme <NUM>. The block-based scheme <NUM> can be associated with the eMBB traffic when the eMBB traffic is a high rank transmission or when operating conditions involve high speed operations.

In another aspect of the method <NUM>, the scheme can be an over-provisioning RS scheme in which additional RS symbols are preemptively scheduled by the base station within slot for the eMBB traffic (see e.g., <FIG>). For example, the scheme identification <NUM> may identify or select the over-provisioning RS scheme <NUM>.

In another aspect of the method <NUM>, the method can further include, at <NUM>, receiving an indication to disable or remove time-domain orthogonal covered code (TD-OCC), and at <NUM>, disabling or removing TD-OCC in response to the indication (see e.g., <FIG>). For example, the TD-OCC may receive the indication <NUM> to disable or remove TD-OCC and disable or remove TD-OCC in response to the indication <NUM>.

Although the operations or methods described above are presented in a particular order and/or as being performed by an example component, it should be understood that the ordering of the actions and the components performing the actions may be varied, depending on the implementation. In addition, aspects of any one of the methods described above can be combined with aspects of any other of the methods.

Information and signals may be represented using any of variety of different technologies and techniques.

The various illustrative blocks and components described in connection with the disclosure herein may be implemented or performed with a specially-programmed device, such as but not limited to processor, a digital signal processor (DSP), an ASIC, a FPGA or other programmable logic device, a discrete gate or transistor logic, a discrete hardware component, or any combination thereof designed to perform the functions described herein.

Claim 1:
A method for wireless communications, comprising:
identifying (<NUM>), at a base station, at least one scheme supported by the base station for handling puncturing of reference signal, RS, symbols in enhanced mobile broadband, eMBB, traffic by ultra-reliable-low-latency communications, URLLC, traffic, wherein each of the at least one scheme modifies an existing RS pattern configured for the eMBB traffic before puncturing occurs in response to a presence of the URLLC traffic, wherein identifying the at least one scheme comprises selecting the at least one scheme from a plurality of schemes supported by the base station based on a pattern of the URLLC traffic, wherein the selected scheme comprises identifying an over-provisioning RS scheme in which additional RS symbols are preemptively scheduled by the base station within a slot for the eMBB traffic before URLLC traffic is scheduled within the slot; and
performing (<NUM>), at the base station, the at least one scheme in connection with downlink transmissions.