Patent Description:
<NPL>, provides remaining details of QCL assumptions. <CIT> discloses a method and device for processing quasi-colocation information. The method comprises: a base station divides M demodulation pilot ports into N demodulation pilot port groups G1,. , and GN, where N1 demodulation port groups are signal demodulation port groups, N2 demodulation port groups are scrambling demodulation port groups, M, N1, and N2 are positive integers, and <NUM> < N ≤ M; and the base station transmits quasi-colocation information of the N demodulation pilot port groups to a terminal. The described technical solution solves the problem in the prior art in which the terminal cannot acquire quasi-colocation parameter information of an interfering DMRS and, as a result, cannot acquire the time offset and frequency offset of an interfering channel and correct the time offset and frequency offset of the frequency interfering with DMRS estimation, thus allowing the terminal to accurately acquire the quasi-colocation information of an interference and to accurately eliminate the impact of the interference, and increasing the performance of a radio communication system.

After considering this discussion, and particularly after reading the section entitled "Detailed Description" one will understand how the features of this disclosure provide advantages that include improved communications between a base station and user equipment in a wireless network.

Certain aspects provide a method for wireless communication by a base station (BS) in accordance with claim <NUM>. The method generally includes generating quasi-colocation (QCL) information indicating a first QCL assumption for a first group of demodulation reference signal (DM-RS) ports and a second QCL assumption for a second group of DM-RS ports; and transmitting the QCL information to at least one user equipment (UE) for use in processing one or more transmission associated with at least one of the first group of DM-RS ports and the second group of DM-RS ports.

Certain aspects provide a method for wireless communication by a user equipment (UE) in accordance with claim <NUM>. The method generally includes obtaining quasi-colocation (QCL) information indicating a first QCL assumption for a first group of demodulation reference signal (DM-RS) ports and a second QCL assumption for a second group of DM-RS ports; and receiving transmissions associated with the first group of DM-RS ports and the second group of DM-RS ports based on the QCL information.

Aspects of the present disclosure also provide various apparatuses, means, and computer program products corresponding to the methods and operations described above.

Aspects of the present disclosure provide apparatus, methods, processing systems, and computer readable mediums for signaling quasi-colocation (QCL) information for demodulation reference signals (DM-RS) associated with multiple transmission-reception points (multi-TRP) or multiple antenna panels (multi-panel). Aspects of the present disclosure provide signaling, to a UE, QCL assumptions linked to multiple antenna port groups. For example, a UE may receive, from a BS, QCL information associated with multiple antenna groups, and the UE may apply the QCL assumptions to receive transmissions via the multiple antenna port groups such as multi-TRP/multi-panel transmissions.

The wireless communication network <NUM> may be a New Radio (NR) or <NUM> network that supports multiple DM-RS port groups for QCL assumptions. For example, UE 120a may receive, from BS 110a, QCL information corresponding to multiple antenna groups, such as demodulation reference signal (DM-RS) port groups. The QCL information may enable the UE 120a to apply QCL assumptions to multi-TRP/multi-panel transmissions, such as transmissions from BS 110a and BS 110b or transmissions from multiple antenna panels ofBS 110a.

As illustrated in <FIG>, the wireless network <NUM> may include a number of base stations (BSs) <NUM> and other network entities. A BS may be a station that communicates with user equipments (UEs). Each BS <NUM> may provide communication coverage for a particular geographic area. In 3GPP, the term "cell" can refer to a coverage area of a Node B (NB) and/or a Node B subsystem serving this coverage area, depending on the context in which the term is used. In NR systems, the term "cell" and next generation NodeB (gNB), new radio base station (NR BS), <NUM> NB, access point (AP), or transmission reception point (TRP) may be interchangeable. In some examples, the base stations may be interconnected to one another and/or to one or more other base stations or network nodes (not shown) in wireless communication network <NUM> through various types of backhaul interfaces, such as a direct physical connection, a wireless connection, a virtual network, or the like using any suitable transport network.

NR may utilize OFDM with a cyclic prefix (CP) on the uplink and downlink and include support for half-duplex operation using TDD.

<FIG> illustrates example components of BS <NUM> and UE <NUM> (as depicted in <FIG>), which may be used to implement aspects of the present disclosure. For example, antennas <NUM>, processors <NUM>, <NUM>, <NUM>, and/or controller/processor <NUM> of the UE <NUM> and/or antennas <NUM>, processors <NUM>, <NUM>, <NUM>, and/or controller/processor <NUM> of the BS <NUM> may be used to perform the various techniques and methods described herein (<FIG> and <FIG>). For example, UE <NUM> may receive, from BS <NUM>, QCL information corresponding to multiple antenna groups, such as demodulation DM-RS port groups. The QCL information may enable the UE <NUM> to apply QCL assumptions to receive transmissions via the multiple antenna port groups, such as multi-TRP/multi-panel transmissions.

Each slot may include a variable number of symbol periods (e.g., <NUM>, <NUM>, or <NUM> symbols) depending on the subcarrier spacing.

Aspects of the present disclosure provide techniques for providing quasi-colocation (QCL) signaling for groups of demodulation reference signal (DM-RS) ports across scenarios involving multiple cells and/or multiple panels (multi-panel), such as coordinated multipoint (CoMP) scenarios in which a UE is connected to multiple transmit receive points (TRPs).

QCL assumptions generally refer to assumptions that, for a set of signals or channels considered to be QCL related (or simply "QCL'd" for short), certain characteristics derived for (measured from) one of the signals or channels may be applied to the other. As an example, if PDSCH DMRS is QCL'd with other DL RS, a UE may process PDSCH and measure the associated DM-RS based on characteristics/measurements of the other DL RS.

In some cases, QCL assumptions for receptions/transmissions of signals and channels may be signaled via a mechanism referred to as Transmission Configuration Indicator (TCI) states. <FIG> illustrates an example TCI state used to configure a DM-RS port group via control signaling, in accordance with certain aspects of the present disclosure. In this example, the TCI state includes a single QCL configuration having at least two types of QCL information, which may provide QCL assumptions for two different DL reference signals. In some cases, a UE may be configured with various TCI states via radio resource control (RRC) signaling, while one of the actual TCI states may be indicated by an N bit DCI field for PDSCH. In some other cases, a UE may be configured with a subset of various TCI states (e.g., up to <NUM> TCI states) via MAC control signaling (e.g., a MAC control element (MAC-CE)), and downlink control signaling (e.g., DCI) may be used to select a TCI state out of the subset (e.g., <NUM> bits may be used to identify which TCI state is enabled).

<FIG> illustrates an example of QCL information that may be included in a QCL configuration, in accordance with certain aspects of the present disclosure. The QCL assumptions may be grouped into different types that correspond to the parameters that may be assumed QCL'd for a set of QCL'd signals. For example, for a set of QCL'd signals, Type A may indicate that Doppler shift, Doppler spread, average delay, delay spread can be assumed QCL'd, while Type B may indicate only Doppler shift and Doppler spread, Type C may indicate a still different set of parameters. In some cases, spatial QCL assumptions may be indicated, for example, by Type D. Spatial QCL may mean a (Tx or Rx) beam selected based on a certain signal measurement may be applied to the QCL related signal. As an example, the QCL assumptions may provide a QCL relationship between a DM-RS and at least one of a channel state information reference signal (CSI-RS) or a synchronization signal (SS). As used herein, a set of QCL'd signals refers to the QCL relationship between those signals (e.g., Doppler shift, Doppler spread, average delay, and/or delay spread).

One limitation of the current QCL configuration is that only one TCI state consisting of a single QCL assumption is provided per DL transmission. That is, all the DM-RS ports have the same QCL assumptions. In some cases, multiple DM-RS port groups are configured for a DL transmission, but the current QCL configuration only supports signaling of a single QCL assumption. Aspects of the present disclosure, however, extend the QCL configuration to allow signaling of QCL assumptions linked to multiple antenna port groups. As such, the QCL signaling described herein may be applied in multi-TRP/multi-panel scenarios, such as CoMP deployments where multiple transmission reception points (TRPs) communicate with a UE.

<FIG> is a flow diagram illustrating example operations <NUM> that may be performed, for example, by a base station (e.g., BS <NUM>), for configuring DM-RS transmissions with QCL information that supports multi-TRP transmissions, in accordance with certain aspects of the present disclosure.

Operations <NUM> may begin, at <NUM>, where the BS generates quasi-colocation (QCL) information indicating a first QCL assumption for a first group of demodulation reference signal (DM-RS) ports and a second QCL assumption for a second group of DM-RS ports. At <NUM>, the BS transmits the QCL information to at least one user equipment (UE) for use in processing one or more transmission associated with at least one of the first group of DM-RS ports and the second group of DM-RS ports.

<FIG> is a flow diagram illustrating example operations <NUM> that may be performed, for example, by a user equipment (e.g., UE <NUM>), for configuring DM-RS transmissions with QCL information that supports multi-TRP/multi-panel transmissions, in accordance with certain aspects of the present disclosure.

Operations <NUM> may begin, at <NUM>, where the UE obtains quasi-colocation (QCL) information indicating a first QCL assumption for a first group of demodulation reference signal (DM-RS) ports and a second QCL assumption for a second group of DM-RS ports. At <NUM>, the UE receives transmissions associated with the first group of DM-RS ports and the second group of DM-RS ports based on the QCL information.

The QCL information may be transmitted to the UE via control signaling such as radio resource control (RRC) signaling (e.g., RRC element), medium access control (MAC) signaling (e.g., MAC control element (MAC-CE)), or downlink control signaling (e.g., downlink control information (DCI)). For example, the UE may be initially configured with various TCI states (e.g., up to <NUM> TCI states per DL transmission) via RRC signaling, and DCI signaling may be used to select one or more of the TCI states (e.g., <NUM> bits may be used to select the TCI states used for the DL transmissions). The UE may determine QCL assumptions associated with the DM-RS port groups based on the QCL information signaled to the UE. The UE may then monitor and receive transmissions associated with the DM-RS port groups based on the QCL assumptions.

In certain aspects, the QCL information may be indicated via a TCI state having at least a first QCL configuration and a second QCL configuration. <FIG> illustrates an example TCI state used to configure DM-RS port groups via control signaling, in accordance with certain aspects of the present disclosure. As illustrated in <FIG>, the TCI state may provide the QCL assumptions for at least two DM-RS port groups. For example, the UE may assume that the first QCL configuration (qcl-Config1) provides the QCL assumptions for the first group of DM-RS ports, and that the second QCL configuration (qcl-Config2) provides the QCL assumptions for the second group of DM-RS ports. In situations where one of the QCL configuration provides no QCL information (i.e., the field is reserved), the first QCL configuration may be applied to the QCL assumptions for the first and second group of DM-RS ports, or vice versa. In other aspects, the first QCL configuration may be applied to the QCL assumptions for the first group of DM-RS ports, and a default QCL configuration may be applied to the QCL assumptions for the second group of DM-RS ports, or vice versa.

If the UE is configured with only one DM-RS port group, all the ports are QCL'd with the same QCL information in the TCI state. As examples, if the UE obtains only one QCL configuration, then that QCL configuration is applied to the configured DM-RS port group. If the UE obtains two QCL configurations, then the UE may apply the first QCL configuration to the configured DM-RS port group. In other aspects, the UE may apply the QCL configuration based on the index of the DM-RS port group. For example, if the configured DM-RS port group has an index indicating that it is the first DM-RS port group, the UE may apply the first QCL configuration to the configured DM-RS port group, and if the configured DM-RS port group has an index indicating that it is the second DM-RS port group, then the UE may apply the second QCL configuration to the configured DM-RS port group.

For aspects, the QCL information may be indicated via a plurality of TCI states, and each of the TCI states comprises a QCL configuration. For example, the TCI state shown in <FIG> may be used as one of the plurality of TCI states. As an example, an indication having the plurality of TCI states, each of the TCI states having a QCL configuration associated with a DM-RS port group, may be signaled, by the BS, to the UE via a control message, such as a RRC message, MAC-CE message, or DCI message. That is, the plurality of TCI states supporting multi-TRP/multi-panel transmissions may be signaled via a single indicator included in a control message transmitted to the UE. The UE may receive the control message having the TCI states and determine the QCL assumptions for the DM-RS port groups based on the TCI states.

For aspects, the QCL information may be indicated via a TCI state having a single QCL configuration. The UE may assume that the QCL configuration applies to the QCL assumptions for the first and second group of DM-RS ports. In other aspects, the UE may assume that the QCL configuration applies to the QCL assumptions for the first group of DM-RS ports, and that a default QCL configuration applies to the QCL assumptions for the second group of DM-RS ports.

In certain aspects, the UE may determine QCL assumptions for the DM-RS port groups based on a cell identification (cell ID). For instance, the UE may be connected to a TRP having a certain cell ID as configured via RRC signaling. If the cell ID provided in a TCI state is the same as the cell ID provided in the RRC signaling, the QCL configuration provided in the TCI state is applied to the first DM-RS port group, and a default QCL configuration is applied to the second DM-RS port group. In other aspects, if the cell ID provided in the TCI state is different from the cell ID provided in the RRC signaling, the QCL configuration provided in the TCI state is applied to the second DM-RS port group, and a default QCL configuration is applied to the first DM-RS port group.

In certain aspects, the UE may report its capability of supporting DM-RS port groups with different QCL assumptions to the BS. Based on this reporting, higher-layer signaling may provide a maximum number of supported DM-RS port groups to the UE. In aspects, the BS may provide the UE with an indication of the maximum number of supported DM-RS port groups. The UE may determine the payload size of downlink control signaling (e.g., DCI) based at least in part on the configured maximum number of supported DM-RS port groups. The UE may also determine how to apply the QCL assumptions included in the one or more TCI state(s) based on the maximum number of supported DM-RS port groups as further described herein.

As examples, if the maximum number of supported DM-RS port groups is set to <NUM>, and one QCL assumption is provided in the TCI state(s), then the UE applies the QCL configuration to the sole DM-RS port group configured. If the maximum number of supported DM-RS port groups is set to <NUM>, and two QCL assumptions are provided in the TCI state(s), then the UE may assume the first QCL configuration applies to the sole DM-RS port group configured. If the maximum number of supported DM-RS port groups is set to <NUM>, and two QCL assumptions are provided in the TCI state(s), then the UE may apply the QCL assumption with a cell ID and bandwidth part (BWP) ID that matches the cell ID and BWP ID of the DM-RS port group.

As other examples, if the maximum number of supported DM-RS port groups is set to <NUM>, only one DM-RS port group is configured, and one QCL assumption is provided in the TCI state(s), then the UE applies the QCL assumption to the configured DM-RS port group. In other aspects, if the maximum number of supported DM-RS port groups is set to <NUM>, only one DM-RS port group is configured, and one QCL assumption is provided in the TCI state(s), then the UE applies the QCL assumption to the first DM-RS port group, if the QCL assumption is from the first QCL configuration, or applies the QCL assumption to the second DM-RS port group, if the QCL assumption is from the second QCL configuration. Otherwise, the UE applies a default QCL assumption to the DM-RS port group.

In certain aspects, if the maximum number of supported DM-RS port groups is set to <NUM>, only one DM-RS port group is configured, and two QCL assumptions are provided in the TCI state(s), then the UE may apply the QCL assumption to the first DM-RS port group, if the QCL assumption is from the first QCL configuration, or the UE may apply the QCL assumption to the second DM-RS port group, if the QCL assumption is from the second QCL configuration. In other aspects, if the maximum number of supported DM-RS port groups is set to <NUM>, only one DM-RS port group is configured, and two QCL assumptions are provided in the TCI state(s), then the UE may apply the QCL assumption with a cell ID and BWP ID that matches the cell ID and BWP ID of the corresponding DM-RS port group.

As further examples, if the maximum number of supported DM-RS port groups is set to <NUM>, two DM-RS port groups are configured, and only one QCL assumption is provided in the TCI state(s), then the UE may apply the same QCL assumption to both groups. In other aspects, if the maximum number of supported DM-RS port groups is set to <NUM>, two DM-RS port groups are configured, and only one QCL assumption is provided in the TCI state(s), then the UE may apply the QCL assumption to the corresponding DM-RS port group and apply a default QCL assumption to the other DM-RS port group.

In aspects, the maximum number of supported DM-RS port groups may also be indicated by a maximum number of QCL configurations per DL transmissions. That is, the maximum number of QCL configurations per DL transmissions may be used as higher layer signaling and provided to the UE in determining how to apply the QCL assumptions as described herein.

<FIG> illustrates a communications device <NUM> (such as a BS <NUM> or a UE <NUM>) that may include various components (e.g., corresponding to means-plus-function components) configured to perform operations for the techniques disclosed herein, such as the operations illustrated in <FIG> and <FIG>. The communications device <NUM> includes a processing system <NUM> coupled to a transceiver <NUM> (e.g., a transmitter and/or receiver). The transceiver <NUM> is configured to transmit and receive signals for the communications device <NUM> via an antenna <NUM>, such as the various signal described herein.

The processing system <NUM> includes a processor <NUM> coupled to a computer-readable medium/memory <NUM> via a bus <NUM>. In certain aspects, the computer-readable medium/memory <NUM> is configured to store instructions that when executed by processor <NUM>, cause the processor <NUM> to perform the operations illustrated in <FIG> and <FIG>, or other operations for performing the various techniques discussed herein.

In certain aspects, the processing system <NUM> further includes a transmit/receive component <NUM> for performing the operations illustrated in <FIG> and <FIG>. Additionally, the processing system <NUM> includes a generating component <NUM> for performing the operations illustrated in <FIG> and <FIG>. Additionally, the processing system <NUM> includes an obtaining component <NUM> for performing the operations illustrated in <FIG> and <FIG>. The transmit/receive component <NUM>, generating component <NUM>, and obtaining component <NUM> may be coupled to the processor <NUM> via bus <NUM>. In certain aspects, the transmit/receive component <NUM>, generating component <NUM>, and obtaining component <NUM> may be hardware circuits. In certain aspects, the transmit/receive component <NUM>, generating component <NUM>, and obtaining component <NUM> may be software components that are executed and run on processor <NUM>.

Generally, where there are operations illustrated in figures, those operations may have corresponding counterpart means-plus-function components.

In the case of a user equipment <NUM> (see <FIG>), a user interface (e.g., keypad, display, mouse, joystick, etc.) may also be connected to the bus.

For example, such a computer program product may comprise a computer-readable medium having instructions stored (and/or encoded) thereon, the instructions being executable by one or more processors to perform the operations described herein and illustrated in <FIG> and <FIG>.

Claim 1:
A method of wireless communication by a base station, BS (<NUM>), comprising:
receiving from at least one UE, a UE capability of supporting demodulation reference signal DM-RS port groups with different QCL assumptions;
generating (<NUM>) quasi-colocation, QCL information indicating a first QCL assumption for a first group of demodulation reference signal, DM-RS ports and a second QCL assumption for a second group of DM-RS ports, wherein the QCL information is indicated via a plurality of transmission configuration indicator, TCI states, each of the TCI states comprises a QCL configuration and wherein transmitting the QCL information comprises transmitting the plurality of TCI states via control signaling including at least one of a radio resource control, RRC element, a medium access control, MAC element, or downlink control information, DCI, the control signaling having a payload size based at least in part on a maximum number of supported DM-RS port groups, and wherein the maximum number of supported DM-RS port groups is determined based on, receiving from the at least one UE, the UE capability of supporting DM-RS port groups with different QCL assumptions;
transmitting (<NUM>) the QCL information to the at least one user equipment, UE (<NUM>) for use in processing one or more transmission associated with at least one of the first group of DM-RS ports and the second group of DM-RS ports.