WO2022205452A1

WO2022205452A1 - Reference signal configuration for multi-beam communication in wireless networks

Info

Publication number: WO2022205452A1
Application number: PCT/CN2021/085389
Authority: WO
Inventors: Shujuan Zhang; Zhaohua Lu; Hao Wu; Shijia SHAO; Yu Pan
Original assignee: Zte Corporation
Priority date: 2021-04-02
Filing date: 2021-04-02
Publication date: 2022-10-06
Also published as: CN117083942A

Abstract

Methods, systems, and devices for configuring reference signals for multi-beam communications in mobile cellular networks are described. An example method for wireless communication includes receiving, by a wireless terminal, a control message comprising a configuration indication, and identifying, based on the configuration indication, N reference signal elements, wherein N is a positive integer, and wherein a reference signal element of the N reference signal elements comprises a reference signal resource or a set of reference signal resources.

Description

REFERENCE SIGNAL CONFIGURATION FOR MULTI-BEAM COMMUNICATION IN WIRELESS NETWORKS

TECHNICAL FIELD

This document is directed generally to wireless communications.

BACKGROUND

Wireless communication technologies are moving the world toward an increasingly connected and networked society. The rapid growth of wireless communications and advances in technology has led to greater demand for capacity and connectivity. Other aspects, such as energy consumption, device cost, spectral efficiency, and latency are also important to meeting the needs of various communication scenarios. In comparison with the existing wireless networks, next generation systems and wireless communication techniques will provide support for an increased number of users and devices, as well as support for higher data rates, through beamforming and multi-beam communication techniques.

SUMMARY

This document relates to methods, systems, and devices for configuring reference signals for multi-beam communication in mobile cellular networks, including 5th Generation (5G) and New Radio (NR) communication systems.

In an aspect, a wireless communication method is disclosed. The method includes receiving, by a wireless terminal, a control message comprising a configuration indication, and identifying, based on the configuration indication, N reference signal elements, wherein N is a positive integer, and wherein a reference signal element of the N reference signal elements comprises a reference signal resource or a set of reference signal resources.

In another aspect, a wireless communication method is disclosed. The method includes transmitting, by a network node, a control message comprising a configuration indication, identifying, based on the configuration indication, N reference signal elements, and transmitting the N reference signal elements, wherein N is a positive integer, and wherein a reference signal element of the N reference signal elements comprises a reference signal resource or a set of reference signal resources.

In yet another aspect, a wireless communication method is disclosed. The method includes receiving, by a wireless terminal, a control message comprising N signaled Transmission Configuration Indication (TCI) states, wherein N is a positive integer, and determining, based on one or more reference signal elements, a time unit from which one or more signaled TCI states of the N signaled TCI states are starting to be applied.

In yet another aspect, a wireless communication method is disclosed. The method includes transmitting, by a network node to a wireless device, a control message comprising N signaled Transmission Configuration Indication (TCI) states, wherein N is a positive integer, determining, based on one or more reference signal elements, a time unit from which one or more signaled TCI states of the N signaled TCI states are starting to be applied, and transmitting, to the wireless device, a channel or a signal with a signaled TCI state of the N signal TCI states from the time unit.

In yet another aspect, the above-described methods are embodied in the form of processor-executable code and stored in a computer-readable program medium.

In yet another aspect, a device that is configured or operable to perform the above-described methods is disclosed.

The above and other aspects and their implementations are described in greater detail in the drawings, the descriptions, and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an example of a base station (BS) and user equipment (UE) in wireless communication, in accordance with some embodiments of the presently disclosed technology.

FIG. 2 shows an example of a new Transmission Configuration Indication (TCI) state in mode 2 activated by a Medium Access Control (MAC) -Control Element (CE) starting to be applied after a first synchronization signal block (SSB) transmission.

FIG. 3 shows an example of a new TCI state in mode 1 activated by a MAC-CE starting to be applied after an RX refinement duration and a first SSB transmission.

FIG. 4 shows an example of a MAC-CE with TCI states triggering an aperiodic reference signal (RS) element.

FIG. 5 shows an example of a MAC-CE with TCI states triggering a reference signal element transmitted with multiple transmission occasions.

FIG. 6 shows an example of a pattern of a UE-specific SSB.

FIG. 7 shows an example of a UE determining whether a new TCI state will trigger a reference element based on whether a corresponding SSB transmission is in a window.

FIG. 8 shows an example of mapping between N signaled TCI states and a first N reference element configurations in a predefined reference element configuration list.

FIGS. 9-11 show examples of the activation delay of a new TCI state.

FIG. 12 is a block diagram representation of a portion of an apparatus that can be configured to implement some embodiments of the presently disclosed technology.

FIGS. 13-16 show examples of wireless communication methods corresponding to some embodiments of the presently disclosed technology.

DETAILED DESCRIPTION

5G and NR systems are being configured to support the Quasi Co-Location (QCL) concept, which assists the UE with synchronization, channel estimation and frequency offset error estimation procedures. Two antenna ports are said to be quasi co-located (QCL-ed) if properties of the channel over which a symbol on one antenna port is communicated can be inferred from the channel over which a symbol on the other antenna port is communicated. For example, if a wireless device (e.g., UE) knows that the radio channels corresponding to two different antenna ports is QCL in terms of Doppler shift, then the UE can determine the Doppler shift for one antenna port and then apply the result on both antenna ports for channel estimation. This avoids the UE to calculate Doppler for both antenna port separately.

Another technique that is employed in 5G and NR systems is beam switching, which is implemented by switching TCI states. In existing implementations, the UE determines large-scale properties of a target channel using one or more TCI states corresponding to the channel. Typically, the UE only tracks reference signals in the active TCI state list. In these systems, the gNB can dynamically switch beams among those specified in a beam state list. When a new TCI state is activated by a MAC-CE , the UE needs to wait for a first transmission of a synchronization signal block (SSB) that is quasi-colocated with the reference signal (RS) in the new TCI state. The UE may use the SSB corresponding to the RS in the new TCI state to determine the large-scale properties of the RS in the new TCI state.

The new TCI state is an active TCI state, which is added to the active TCI state list after the activation delay of the new TCI state second instance, as shown in FIG. 2. As shown therein, the activation delay is the interval between first instance and second instance. The Physical Downlink Shared Channel (PDSCH) with the MAC-CE carrying the new TCI state ends at the first instance, and the new TCI state starts to be applied from the second instance. The new TCI state starting to be applied means that the UE can receive a channel and/or a signal with the new TCI state. That is, the QCL-RS of the channel and/or signal is the RS in the new TCI state. The activation delay includes a duration that corresponds to waiting for the first SSB transmission associated with the new TCI state, as shown in FIG. 2. As described earlier, the activation delay of the new TCI state will be too large when the period of SSB is large. This results in the beam switching speed to be slow, and if the beam cannot be switched in time, a radio link failure results.

In another scenario, if the new TCI state is a TCI state in mode 1 (e.g., an unknown TCI state) with QCL-Type D, the activation delay of the new TCI state will be larger than an activation delay for a TCI state in mode 2 (e.g., a new known TCI state) , as shown in FIG. 3. Compared with the scenario in FIG. 2, the activation delay for an unknown new TCI state includes an additional duration of T _L1-RSRP which is used by the UE to get a receive (Rx) beam refinement. The duration T _L1-RSRP includes one or more periods of SSB or CSI-RS corresponding to the RS in the new TCI state. The activation delay of a new unknown TCI state will typically be larger.

FIG. 1 shows an example of a wireless communication system (e.g., an LTE, 5G or New Radio (NR) cellular network) that includes a BS 120 and one or more user equipment (UE) 111, 112 and 113. In some embodiments, the downlink transmissions (141, 142, 143) include a control message comprising a configuration indication, which is followed by the identified reference signal elements. The UEs subsequently transmit (131, 132, 133) data to the BS 120 using at least one of the reference signal elements. The UE may be, for example, a smartphone, a tablet, a mobile computer, a machine to machine (M2M) device, a terminal, a mobile device, an Internet of Things (IoT) device, and so on.

As discussed earlier, when a new TCI state is activated by a Medium Access Control (MAC) -Control Element (CE) or Downlink Control Information (DCI) , the new TCI state will start to be applied after a first SSB transmission associated with the new TCI state. The activation delay of the new TCI state will be too large if the period of SSB is large. Embodiments of the disclosed technology provide methods and systems to reduce the activation delay of the new TCI state.

The present document uses section headings and sub-headings for facilitating easy understanding and not for limiting the scope of the disclosed techniques and embodiments to certain sections. Accordingly, embodiments disclosed in different sections can be used with each other. Furthermore, the present document uses examples from the 3GPP New Radio (NR) network architecture and 5G protocol only to facilitate understanding and the disclosed techniques and embodiments may be practiced in other wireless systems that use different communication protocols than the 3GPP protocols.

Example embodiments for configuring TCI states

In some embodiments, a DCI or a MAC-CE with TCI state indication can trigger UE to receive one or more reference signal resources (e.g., the reference signal elements) , each of which can be aperiodic as shown in FIG. 4, or can be transmitted with multiple transmission occasions as shown in FIG. 5. As shown in FIG. 5, when it is transmitted with multiple transmission occasions, the periodic offset and/or the number of the transmission occasions (denoted M) can be configured, predefined, or based on whether the new TCI state is in mode 1 (e.g., an unknown TCI state) . The reference signal resource can be Channel State Information (CSI) -Reference Signal (RS) or a Synchronization Signal Block (SSB) . In an example, the triggered SSB may be a UE-Specific SSB with pattern as shown in FIG. 6. The triggered SSB is also referred to as an SSB-like-CSI-RS, which has a pattern similar to the SSB as shown in FIG. 6. In another example, the pattern of a SSB-like-CSI-RS is identical to that of a Secondary Synchronization Signal (SSS) and/or a Primary Synchronization Signal (PSS) , but without the PBCH in FIG. 6.

In some embodiments, the DCI or MAC-CE with the TCI state indication can also trigger one or more reference signal resource sets (e.g., the reference signal elements) . The number of reference signal resources in a reference signal resource set is predefined or depends on whether the TCI state corresponding to the reference signal resource set is in mode 1 (e.g., an unknown TCI state) .

In some embodiments, a TCI state is known if the following conditions are met-during the period from the last transmission of the RS resource used for the L1-RSRP measurement reporting for the TCI state to the completion of active TCI state switch, i.e., the time when the TCI state is available such as second instance as shown in FIG. 2, wherein the RS resource for L1-RSRP measurement is the RS in the TCI state or QCL-ed to the TCI state. Herein, the TCI state switch command is received within 1280ms from the last transmission of the RS resource for beam reporting or measurement, and the UE has sent at least one L1-RSRP report for the TCI state before the TCI state switch command, e.g., the MAC-CE, as shown in FIG. 2. The TCI state and the SSB associated with the TCI state remain detectable during the TCI state switching period, and the SNR of the TCI state ≥ -3dB. Otherwise, the TCI state is unknown. In an example, the modes of a TCI state include known and unknown. In another example, additional modes can be introduced. For example, the mode of the TCI state can be determined based on whether the corresponding SSB of the TCI state is in a window or in an SSB pool.

In an example, the MAC-CE/DCI triggers one or more CSI-RS resource sets each of which comprises four CSI-RS resources. The four CSI-RS resources are in two continuous slots each of which comprise two of the four CSI-RS resources. The reference signal resource can be a TRS, which implies the trs-info parameter of the CSI-RS set is set to be true.

In the examples shown in FIGS. 4 and 5, the signaling with the TCI state indication is a MAC-CE. The triggered reference signal resource is after an acknowledgement (ACK) message for the PDSCH. When the signaling is a DCI, the interval between the DCI and the triggered reference signal resource does not comprise an ACK for the DCI. In other examples, whether the interval between DCI and triggered reference signal resource comprises an ACK for the DCI is based on specific configuration.

In some embodiments, the reference signal resource/resource set (e.g., reference signal elements) is triggered by the MAC-CE/DCI when a predefined condition is satisfied. The predefined condition being satisfied is based on at least one of following: a feature (or property) of the TCI states included in the MAC-CE, an indication in the MAC-CE/DCI, whether there is a SSB transmission in a time window, or whether there is an SSB transmission in an SSB pool. For example, when at least one of following condition is satisfied, the MAC-CE/DCI triggers the reference signal resource/resource set.

Condition 1. There is at least one new TCI state in the DCI/MAC-CE. A TCI state is a new TCI state corresponds to the TCI state not being in an active TCI state list and the TCI state is not activated before the DCI/MAC-CE. The active TCI state list comprises at least one of a TCI state activated/applied before the DCI/MAC-CE and the TCI states that are designated for PDSCH and/or Physical Downlink Control Channel (PDCCH) . In an example, a first DCI/MAC-CE activates TCI states 1-5 at a first time, and a second DCI/MAC-CE activates TCI states 1-4, 6 and 7 at a second time; herein, TCI states 6 and 7 are the new TCI states.

Condition 2. There is at least one new unknown TCI state in the DCI/MAC-CE. As shown in FIG. 5, a number of transmission occasions of the triggered reference signal resources corresponding to a new unknown TCI state is larger than the number of transmission occasions of the triggered reference signal resources corresponding to a new known TCI state.

Condition 3. The DCI/MAC-CE further indicates that it will trigger the reference signal resource/resource set. The indication of the DCI/MAC-CE may be a single bit that indicates whether the DCI/MAC-CE will trigger the reference signal resource/resource set. Alternatively, the indication of the DCI/MAC-CE may be one or more bits which indicate which TCI states will trigger a corresponding reference signal resource/resource set. Each of the one or more bits corresponds to a TCI state in the TCI state list included in the DCI/MAC-CE. In an example, the one or more bits can be a bitmap, and each of the one or more bits is associated with a TCI state in the DCI/MAC-CE.

Condition 4. There is at least one new TCI state for which triggered the reference signal resource/resource set is configured. As shown in Table 1, TCI state n is configured not only with QCL-RS but also with parameter of the triggered reference signal resource/resource set. If the TCI state n is a new TCI state in the MAC-CE/DCI, the MAC-CE/DCI will trigger the reference signal resource/resource set corresponding to the TCI state n.

Table 1

Condition 5. There is at least one new TCI state and an SSB transmission corresponding to the new TCI state that is not within a window and/or not in an SSB pool that is based on a communication time of the MAC-CE/DCI and a predefined time length, e.g., one of window 1, window 2, or window 3, as shown in FIG. 7. The SSB corresponding to a TCI state comprises an SSB in the new TCI state or an SSB which is QCL-ed with RS in the TCI state. In an example, the SSB pool includes one or more SSBs. The UE can be configured to track the one or more SSBs in the one or more SSBs.

In some embodiments, the SSB is QCL-ed with RS in the TCI state with respect to a type A channel property or a type C channel property. The type A channel property includes a Doppler shift, a Doppler spread, an average delay, or a delay spread. The type C channel property includes a Doppler shift or an average delay.

Still referring to FIG. 7, if the SSB corresponding to the new TCI state is SSB 2, then the reference signal resource corresponding to the new TCI state will not be triggered because the SSB2 is in the window, i.e., window 2. If the SSB corresponding to the new TCI state is SSB 3, then the reference signal resource corresponding to the new TCI state will be triggered because the SSB3 is not in window 2. Both window 1 and window 2 start a time after the slot comprising the MAC-CE/DCI. Window 2 starts from the end of slot with the MAC-CE/DCI, whereas window 1 starts from the end of slot with the ACK for the MAC-CE/DCI. The window can also starts 3ms after the ACK for the MAC-CE/DCI. Window 3 starts a time before the slot that includes the MAC-CE/DCI.

Condition 6. There is at least one new TCI state in the MAC-CE/DCI and the period of the QCL-RS of the new TCI state is greater than a predefined length.

In some embodiments, the number of reference signal resources (or resource sets) triggered by the MAC-CE/DCI (and denoted Z) is determined by TCI states with predefined feature (e.g., the signaled TCI state) that includes one of following cases.

Case 1. The MAC-CE/DCI triggers a reference signal resource/resource set for each new TCI state in the MAC-CE/DCI.

Case 2. The MAC-CE/DCI triggers a reference signal resource/resource set for each unknown TCI state in the MAC-CE/DCI.

Case 3. The MAC-CE/DCI triggers a reference signal resource/resource set for each TCI state in a TCI state set. The TCI state set includes new TCI states in the MAC-CE/DCI. If two new TCI states with at least one of same QCL RS or with QCL-RSes satisfying QCL-ed relationship, or corresponding to the same SSB, the two new TCI states are assumed to be one TCI state, or equivalently, one of the two TCI states is deleted from the TCI state set.

Tables 2-4 show examples of TCI states. In an example, one of TCI state k and TCI state j will be deleted from the TCI state set because they have same QCL-RS 1. In another example, one of TCI state k and TCI state i will be deleted from the TCI state set because QCL-RS1 and QCL-RS 5 is QCL-ed with respect to QCL-Type A.

Table 2

TCI state k
Information 1	(QCL-RS 1, QCL-Type A)
Information 2	(QCL-RS 2, QCL-Type D)

Table 3

TCI state j
Information 1	(QCL-RS 1, QCL-Type A)
Information 2	(QCL-RS 3, QCL-Type D)

Table 4

TCI state i
Information 1	(QCL-RS 5, QCL-Type A)
Information 2	(QCL-RS 4, QCL-Type D)

Case 4. The MAC-CE/DCI indicates which TCI states trigger a reference signal resource/resource set. For example, the MAC-CE/DCI includes X TCI state. It further indicates Y TCI states of the X TCI states. Each of the Y TCI states will trigger a triggered reference signal resource/resource set. X, Y is an integer. Y is smaller than or equal to the X. Y can be 0.

Case 5. RRC signaling configures TCI state with a parameter of the triggered reference signal resource/resource set as shown in Table 1. If the TCI state is in the DCI/MAC-CE and is a new TCI state or an unknown new TCI state, the reference signal resource/resource set associated with the TCI state will be triggered. For a new TCI state/unknown TCI state without the reference signal resource/resource set, will not trigger the reference signal resource/resource set after the MAC-CE/DCI.

In some embodiments, the parameter of the triggered reference signal resource/resource set is determined using at least one of following methods. In an example, the parameter includes one or more of a sequence parameter, a time-domain resource parameter (e.g., OFDM symbol, slot of the resource/resource set) , a frequency-domain resource parameter (e.g., subcarrier, Physical Resource Block (PRB) of the resource/resource set) , a power parameter, a QCL-RS parameter, or a repetition parameter that can be on or off.

Method 1. The parameter of the triggered reference signal resource/resource set is based on the TCI state included in the DCI/MAC-CE and corresponding to the triggered reference signal resource/resource set. The DCI/MAC-CE indicates which TCI states are used to get the parameter of the triggered reference signal resource/resource set. For example, one or more of a sequence parameter, a time-domain resource parameter, a frequency-domain resource parameter, or a power parameter can be the same as the parameter of a QCL-RS in the TCI state which is one of a new TCI state, an unknown TCI state, a TCI state with an associated triggered reference signal resource/resource set. In this case, the QCL-RS of the triggered reference signal resource is the QCL-RS in the TCI state.

Method 2. The parameter of the triggered reference signal resource can also be configured with the TCI state as shown in Table 1. The parameter is based on the configured parameter associated with a TCI state corresponding to the triggered reference signal resource/resource set.

Method 3. First, the number Z (also referred to as N in this document) of triggered reference signal resources/resource sets is determined, e.g., using the methods described above in Cases 1-5. Then, a first type of parameter of the Z triggered reference signal resources/resource sets is determined based on the first Z reference signal resources/resource sets (e.g., the first N reference signal element configurations) in a reference signal resources/resource sets list (e.g., the reference signal element configuration list) which is predefined or configured. The QCL-RSs of the Z triggered reference signal resources/resource set are determined based on Z TCI states in the DCI or MAC-CE. In other words, the first type of parameter does not include the QCL-RS of the Z triggered reference signal resources/resource set. The mapping of the Z triggered reference signal resources/resource set and Z TCI states is in an order or based on a rule. A TCI state of the Z TCI states (e.g., the one or more signaled TCI states) is new, unknown, with a predefined feature TCI state (also referred to as a signaled TCI state) , or with an indication in the DCI/MAC-CE as described in Conditions 1-6.

As shown in the example in FIG. 8, the new TCI state {TCI state 2, TCI state 4} is mapped to the first two configured triggered reference resource/resource set at a time t1, and the new TCI state {TCI state 8, TCI state 29, TCI state 40, TCI state 49, TCI state 58} is mapped to first five configured triggered reference resources/resource sets at a time t2.

In some embodiments, the Z triggered reference signal resources/resource set is in one or more time units starting from a first time unit after the MAC-CE/DCI. The time unit can be a slot, a sub-slot, or an OFDM symbol.

In some embodiments, the first time unit is determined based on an interval, which includes one of following: a first interval between the channel carrying the MAC-CE/DCI (e.g., the first instance shown in FIGS. 4 or 5) and the reference signal resource/resource set (e.g., the fourth instance shown in FIGS. 4 or 5) , a second interval between the ACK message for PDSCH or PDCCH and the reference signal element, or a third interval between 3ms after the ACK message for PDSCH or PDCCH and the reference signal element. Herein, the PDSCH carries the MAC-CE, or the PDSCH is scheduled by the DCI, or the PDCCH carries the DCI.

In other embodiments, the interval is determined based on an interval associated with a channel or a signal scheduled by the control message. For example, if the control message is DCI, the interval of the Z reference signal resource/resource set is determined to be the interval of a PDSCH/PUCCH/CSI-RS scheduled by the DCI. Herein, the interval of the PDSCH is the time offset between the PDCCH and the PDSCH, the interval of the PUCCH is the time offset between the PDSCH and the PUCCH, and the interval of the PUCCH is the time offset between the PDCCH and the CSI-RS.

In yet other embodiments, the time unit is determined based on a time of a channel or a signal scheduled by the control message. For example, if the control message is the DCI, the channel or signal scheduled by the DCI includes the PDSCH, the PUCCH, and/or the CSI-RS scheduled by the DCI.

Example embodiments for reducing the activation delay

In some embodiments, the activation delay of a new TCI state will not include a duration associated with waiting for a first transmission of SSB corresponding to the new TCI state when the new TCI state corresponds to a triggered reference signal resource/resource set as shown in FIGS. 9-11. However, it will includes a duration T _RS that corresponds to waiting for the transmission of the triggered reference signal resource/resource set corresponding to the new TCI state as shown in FIGS. 9-11. The new TCI state will be applied after the triggered reference signal resource/resource set.

In FIG. 9, the new TCI state is applied starting from slot n + T _HARQ + T _{predefined-length2} + (T _RS + T _{predefined-length1}) /NR slot length, wherein T _HARQ is duration from slot n of PDSCH with MAC-CE to slot with ACK for the PDSCH, T _{predefined-length2} is a predefined time length, e.g., 3ms. T _RS is the duration from ACK to slot with the triggered reference signal resource/resource set. T _{predefined-length1} is a predefined time length, e.g., 2ms. Alternatively, T _{predefined-length1} comprises a duration of triggered reference signal resource/resource set and a predefined time length which starts from the end of the triggered reference signal resource/resource set. The triggered reference signal resource/resource set is after n + T _HARQ + T _{predefined-length2}.

In FIG. 10, the new TCI state is applied starting from slot n + T _HARQ + (T _RS +T _{predefined-length1}) /NR slot length. The triggered reference signal resource/resource set is after n +T _HARQ .

In FIG. 11, the new TCI state is applied starting from slot n + T _HARQ + T _{predefined-length2} + (M×T _RS + T _{predefined-length1}) /NR slot length. The new TCI state is applied starting from a time unit after M occasions of the triggered reference signal resource/resource set. If the new TCI state does not trigger a reference signal resource/resource set and there is an SSB in a time window as shown in FIG. 7, the new TCI state is available in slot n+ T _HARQ + T _{predefined-length2} + (T _SSB + T _{predefined-length1}) /NR slot length, wherein T _SSB is a duration that corresponds to waiting for an SSB of the new TCI state. In other embodiments, the new TCI state is available in slot n+T _HARQ + T _{predefined-length2} + (min (T _SSB, T _RS) + T _{predefined-length1}) /NR slot length, wherein min (T _SSB, T _RS) is the minimum value between T _SSB and T _RS. In some embodiments, the UE determines a time from which a TCI state starts to be applied based on a reference signal element which includes the triggered reference signal element by the TCI state or the corresponding SSB not being triggered by the TCI state.

In some embodiments, if the MAC-CE/DCI includes more than one new TCI state, the more than one new TCI state can be applied from a same time corresponding to the end of Z reference signal resources/resource sets. Alternatively, each of the more than one new TCI state will be applied from a respective time after a reference signal resource/resource set corresponding to the one TCI state.

Example embodiments and methods of the disclosed technology

FIG. 12 is a block diagram representation of a portion of an apparatus, in accordance with some embodiments of the presently disclosed technology. An apparatus 1205, such as a base station or a wireless device (or UE) , can include processor electronics 1210 such as a microprocessor that implements one or more of the techniques presented in this document. The apparatus 1205 can include transceiver electronics 1215 to send and/or receive wireless signals over one or more communication interfaces such as antenna (s) 1220. The apparatus 1205 can include other communication interfaces for transmitting and receiving data. Apparatus 1205 can include one or more memories (not explicitly shown) configured to store information such as data and/or instructions. In some implementations, the processor electronics 1210 can include at least a portion of the transceiver electronics 1215. In some embodiments, at least some of the disclosed techniques, modules or functions are implemented using the apparatus 1205.

FIG. 13 shows an example of a wireless communication method 1300. The method 1300 includes, at operation 1310, receiving, by a wireless terminal, a control message comprising a configuration indication.

The method 1300 includes, at operation 1320, identifying, based on the configuration indication, N reference signal elements, N being a positive integer, and a reference signal element of the N reference signal elements comprising a reference signal resource or a set of reference signal resources.

In some embodiments, the method 1300 further includes the operations of receiving the N reference signal elements, and transmitting, based on at least one of the N reference signal elements, a channel state information (CSI) message or a hybrid automatic repeat request (HARQ) acknowledgement (ACK) message for a Physical Downlink Shared Channel (PDSCH) using a Transmission Configuration Indication (TCI) state determined based on the at least one of the N reference signal elements.

FIG. 14 shows an example of a wireless communication method 1400. The method 1400 includes, at operation 1410, transmitting, by a network node, a control message comprising a configuration indication.

The method 1400 includes, at operation 1420, identifying, based on the configuration indication, N reference signal elements, N being a positive integer.

The method 1400 includes, at operation 1430, transmitting the N reference signal elements, a reference signal element of the N reference signal elements comprising a reference signal resource or a set of reference signal resources.

In some embodiments, the reference signal resource comprises a channel state information reference signal (CSI-RS) resource or a synchronization signal block (SSB) resource.

In some embodiments, a trs-info parameter for the set of reference signal resources is set to true.

In some embodiments, a number of reference signal resources included in the set is predetermined or based on whether a Transmission Configuration Indication (TCI) state corresponding to the set is in a first mode. In an example, the first mode (denoted mode 1) can correspond to an unknown TCI state. Similarly, a second mode (denoted mode 2) can correspond to a new TCI state, and so on.

In some embodiments, the reference signal element is aperiodic with one or more transmission occasions.

In some embodiments, a parameter associated with the multiple transmission occasions is determined based on at least one of a signaling, a predetermined value, or whether a Transmission Configuration Indication (TCI) state corresponding to the reference signal element being in a first mode. In an example, the signaling is a received signaling at the wireless device. In another example, the signaling is a transmitted signaling at the network node.

In some embodiments, the parameter comprises at least one of a number of the multiple transmission occasions, a periodicity, or an offset of the periodicity.

In some embodiments, the N reference signal elements are in one or more time units starting from a first time unit after the control message.

In some embodiments, the first time unit is based on an interval, and wherein the interval is based on (i) a first interval between the control message and the N reference signal elements, (ii) a second interval between an acknowledgement (ACK) message corresponding to the control message and the N reference signal elements, or (iii) a third interval between 3ms after the ACK message and the N reference signal elements.

In some embodiments, the interval is based on an interval associated with a channel or a signal scheduled by the control message.

In some embodiments, the first time unit is based on a time of a channel or a signal scheduled by the control message.

In some embodiments, the configuration indication indicates one or more Transmission Configuration Indication (TCI) states, and wherein each of the one or more TCI states corresponds to one of the N reference signal elements.

In some embodiments, the one or more TCI states belong to a list of TCI states included in the control message.

In some embodiments, the configuration indication comprises one or more bits, and wherein each of the one or more bits is associated with a TCI state in the control message.

In some embodiments, the one or more bits satisfying at least one of the following conditions: a number of the one or more bits is based on a number of TCI states in a list, a number of the one or more bits is based on a maximum number of TCI states in a list, or a value of N is equal to a number of one-valued bits in the one or more bits, wherein the list comprises the TCI states in the control message.

In some embodiments, the configuration indication comprises one or more signaled Transmission Configuration Indication (TCI) states.

In some embodiments, a signaled TCI state of the one or more signaled TCI states comprises a new TCI state.

In some embodiments, a signaled TCI state of the one or more signaled TCI states comprises a quasi-colocation reference signal (QCL-RS) with a period that is greater than a predefined duration.

In some embodiments, a signaled TCI state of the one or more signaled TCI states comprises a TCI state configured with a parameter of one of the N reference signal elements.

In some embodiments, a signaled TCI state of the one or more signaled TCI states comprises a TCI state associated with a bit with a value that indicates that the TCI state corresponds to one of the N reference signal elements.

In some embodiments, a signaled TCI state of the one or more signaled TCI states comprises a quasi-colocation reference signal (QCL-RS) with a corresponding synchronization signal block (SSB) , wherein the corresponding SSB is not within a time window or is not within an SSB pool.

In some embodiments, the corresponding SSB is quasi-colocated with the QCL-RS with respect to a first type of channel property or a second type of channel property.

In some embodiments, the time window is based on a time of the control message and a predefined time duration.

In some embodiments, a signaled TCI state of the one or more signaled TCI states is at least one of a new TCI state, an unknown TCI state, a TCI state comprising a quasi-colocation reference signal (QCL-RS) with a period that is greater than a predefined duration, a TCI state configured with a parameter of one of the N reference signal elements, a TCI state associated with a bit with a value that indicates that the TCI state corresponds to another of the N reference signal elements, or a TCI state comprising a QCL-RS with a corresponding synchronization signal block (SSB) that is not within a time window or not in an SSB pool.

In some embodiments, N is based on a number of the one or more signaled TCI states in the control message.

In some embodiments, upon a determination that a first signaled TCI state and a second signaled TCI state satisfy a condition, the number of signaled TCI states in the control message only accounts for the first signaled TCI state.

In some embodiments, the condition comprises the first and second signaled TCI states corresponding to a same SSB or the QCL-RS of the first and second signaled TCI states being quasi-colocated.

In some embodiments, each of the N reference signal elements corresponds to a respective signaled TCI state of the one or more signaled TCI states.

In some embodiments, a parameter of the N reference signal elements is based on a first N reference signal element configurations in a predefined reference signal element configuration list, and wherein each of the N reference signal elements is mapped to one of the first N reference signal element configurations.

In some embodiments, one or more quasi-colocation reference signals (QCL-RSs) of one of the N reference signal elements is based on one or more QCL-RSs in the signaled TCI state corresponding to the reference signal element.

In some embodiments, a parameter of one of the N reference signal elements is based on a parameter of one or more quasi-colocation reference signals (QCL-RSs) included in the signaled TCI state corresponding to the reference signal element.

In some embodiments, a parameter of one of the N reference signal elements is based on a configured parameter associated with the signaled TCI state corresponding to the reference signal element.

In some embodiments, a number of the one or more signaled TCI states is N, and wherein the one or more signaled TCI states are included in a TCI state list in the control message.

In some embodiments, each of the N reference signal elements corresponds to a signaled TCI state of the N signaled TCI states, and wherein each of the N signaled TCI states corresponds to a reference signal element of the N reference signal elements.

In some embodiments, the parameter comprises at least one of a sequence parameter, a time-domain resource parameter, a frequency-domain resource parameter, a power parameter, a repetition parameter, or a quasi-colocation reference signal (QCL-RS) parameter.

In some embodiments, the configuration indication comprises a bit indicating whether the control message triggers at least one of the N reference signal elements.

In some embodiments, the control message comprises a downlink control information (DCI) or a medium access control (MAC) control element (CE) .

In some embodiments, a signaled TCI state corresponding to one of the N reference signal elements starts to be applied after the reference signal element, and wherein the signaled TCI state is included in the one or more signaled TCI states.

In some embodiments, a signaled TCI state corresponding to one of the N reference signal elements starts to be applied a predefined duration after the reference signal element, and wherein the signaled TCI states is included in the one or more signaled TCI states.

In some embodiments, the one or more signaled TCI states start to be applied after the N reference signal elements.

FIG. 15 shows an example of a wireless communication method 1500. The method 1500 includes, at operation 1510, receiving, by a wireless terminal, a control message comprising N signaled Transmission Configuration Indication (TCI) states, N being a positive integer.

The method 1500 includes, at operation 1520, determining, based on one or more reference signal elements, a time unit from which one or more signaled TCI states of the N signaled TCI states are starting to be applied.

FIG. 16 shows an example of a wireless communication method 1600. The method 1600 includes, at operation 1610, transmitting, by a network node to a wireless device, a control message comprising N signaled Transmission Configuration Indication (TCI) states, N being a positive integer.

The method 1600 includes, at operation 1620, determining, based on one or more reference signal elements, a time unit from which one or more signaled TCI states of the N signaled TCI states are starting to be applied.

The method 1600 includes, at operation 1630, transmitting, to the wireless device, a channel or a signal with a signaled TCI state of the N signal TCI states from the time unit.

In some embodiments, the time unit is a time unit from which one signaled TCI state of the N signaled TCI states starts to be applied.

In some embodiments, the time unit is a time unit after a predefined time duration after a reference signal element of the one or more reference signal elements, and wherein the reference signal element corresponds to the one signaled TCI state.

In some embodiments, the time unit is a time unit from which the N signaled TCI states start to be applied, and wherein all of the N signaled TCI states start to be applied at a same time.

In some embodiments, the time unit is a time unit after a predefined time duration after the one or more reference signal elements.

In some embodiments, a signaled TCI state of the N signaled TCI states comprises at least one of a new TCI state, a TCI state in a first mode, a TCI state comprising a quasi-colocation reference signal (QCL-RS) with a period that is greater than a predefined duration, a TCI state configured with a parameter of the reference signal element, a TCI state associated with a one-valued bit that indicates whether the TCI state corresponds to the reference signal element, a TCI state comprising a QCL-RS with a corresponding synchronization signal block (SSB) that is not within a time window, or a TCI state comprising a QCL-RS with a corresponding SSB that is not within an SSB pool.

In some embodiments, the one or more reference signal elements comprises a reference signal element triggered by the control message.

In some embodiments, the one or more reference signal elements comprises a reference signal element not triggered by the control message.

In some embodiments, the one or more reference signal elements comprises the reference signal element not triggered by the control message and a reference signal element triggered by the control message.

In some embodiments, the one or more reference signal elements comprises a reference signal resource or a reference signal resource set.

In some embodiments, a number of the one or more reference signal elements is based on a value of N.

In some embodiments, each of the one or more reference signal elements corresponds to a signaled TCI state of the N signaled TCI states.

Some of the embodiments described herein are described in the general context of methods or processes, which may be implemented in one embodiment by a computer program product, embodied in a computer-readable medium, including computer-executable instructions, such as program code, executed by computers in networked environments. A computer-readable medium may include removable and non-removable storage devices including, but not limited to, Read Only Memory (ROM) , Random Access Memory (RAM) , compact discs (CDs) , digital versatile discs (DVD) , etc. Therefore, the computer-readable media can include a non-transitory storage media. Generally, program modules may include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. Computer-or processor-executable instructions, associated data structures, and program modules represent examples of program code for executing steps of the methods disclosed herein. The particular sequence of such executable instructions or associated data structures represents examples of corresponding acts for implementing the functions described in such steps or processes.

Some of the disclosed embodiments can be implemented as devices or modules using hardware circuits, software, or combinations thereof. For example, a hardware circuit implementation can include discrete analog and/or digital components that are, for example, integrated as part of a printed circuit board. Alternatively, or additionally, the disclosed components or modules can be implemented as an Application Specific Integrated Circuit (ASIC) and/or as a Field Programmable Gate Array (FPGA) device. Some implementations may additionally or alternatively include a digital signal processor (DSP) that is a specialized microprocessor with an architecture optimized for the operational needs of digital signal processing associated with the disclosed functionalities of this application. Similarly, the various components or sub-components within each module may be implemented in software, hardware or firmware. The connectivity between the modules and/or components within the modules may be provided using any one of the connectivity methods and media that is known in the art, including, but not limited to, communications over the Internet, wired, or wireless networks using the appropriate protocols.

While this document contains many specifics, these should not be construed as limitations on the scope of an invention that is claimed or of what may be claimed, but rather as descriptions of features specific to particular embodiments. Certain features that are described in this document in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable sub-combination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a sub-combination or a variation of a sub-combination. Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results.

Only a few implementations and examples are described and other implementations, enhancements and variations can be made based on what is described and illustrated in this disclosure.

Claims

A method of wireless communication, comprising:

receiving, by a wireless terminal, a control message comprising a configuration indication; and

identifying, based on the configuration indication, N reference signal elements,

wherein N is a positive integer, and

wherein a reference signal element of the N reference signal elements comprises a reference signal resource or a set of reference signal resources.
The method of claim 1, further comprising:

receiving the N reference signal elements; and

transmitting, based on at least one of the N reference signal elements, a channel state information (CSI) message or a hybrid automatic repeat request (HARQ) acknowledgement (ACK) message for a Physical Downlink Shared Channel (PDSCH) using a Transmission Configuration Indication (TCI) state determined based on the at least one of the N reference signal elements.
A method of wireless communication, comprising:

transmitting, by a network node, a control message comprising a configuration indication;

identifying, based on the configuration indication, N reference signal elements; and

transmitting the N reference signal elements,

wherein N is a positive integer, and

wherein a reference signal element of the N reference signal elements comprises a reference signal resource or a set of reference signal resources.
The method of any of claims 1 to 3, wherein the reference signal resource comprises a channel state information reference signal (CSI-RS) resource or a synchronization signal block (SSB) resource.
The method of any of claims 1 to 3, wherein a trs-info parameter for the set of reference signal resources is set to true.
The method of any of claims 1 to 3, wherein a number of reference signal resources included in the set is predetermined or based on whether a Transmission Configuration Indication (TCI) state corresponding to the set is in a first mode.
The method of any of claims 1 to 3, wherein the reference signal element is aperiodic with one or more transmission occasions.
The method of claim 7, wherein a parameter associated with the multiple transmission occasions is determined based on at least one of a signaling, a predetermined value, or whether a Transmission Configuration Indication (TCI) state corresponding to the reference signal element being in a first mode.
The method of claim 8, wherein the parameter comprises at least one of a number of the multiple transmission occasions, a periodicity, or an offset of the periodicity.
The method of any of claims 1 to 3, wherein the N reference signal elements are in one or more time units starting from a first time unit after the control message.
The method of claim 10, wherein the first time unit is based on an interval, and wherein the interval is based on (i) a first interval between the control message and the N reference signal elements, (ii) a second interval between an acknowledgement (ACK) message corresponding to the control message and the N reference signal elements, or (iii) a third interval between 3ms after the ACK message and the N reference signal elements.
The method of claim 11, wherein the interval is based on an interval associated with a channel or a signal scheduled by the control message.
The method of claim 10, wherein the first time unit is based on a time of a channel or a signal scheduled by the control message.
The method of any of claims 1 to 3, wherein the configuration indication indicates one or more Transmission Configuration Indication (TCI) states, and wherein each of the one or more TCI states corresponds to one of the N reference signal elements.
The method of claim 14, wherein the one or more TCI states belong to a list of TCI states included in the control message.
The method of claim 14, wherein the configuration indication comprises one or more bits, and wherein each of the one or more bits is associated with a TCI state in the control message.
The method of claim 16, wherein the one or more bits satisfying at least one of the following conditions:

a number of the one or more bits is based on a number of TCI states in a list,

a number of the one or more bits is based on a maximum number of TCI states in a list, or

a value of N is equal to a number of one-valued bits in the one or more bits,

wherein the list comprises the TCI states in the control message.
The method of any of claims 1 to 3, wherein the configuration indication comprises one or more signaled Transmission Configuration Indication (TCI) states.
The method of claim 18, wherein a signaled TCI state of the one or more signaled TCI states comprises a new TCI state.
The method of claim 18, wherein a signaled TCI state of the one or more signaled TCI states comprises a quasi-colocation reference signal (QCL-RS) with a period that is greater than a predefined duration.
The method of claim 18, wherein a signaled TCI state of the one or more signaled TCI states comprises a TCI state configured with a parameter of one of the N reference signal elements.
The method of claim 18, wherein a signaled TCI state of the one or more signaled TCI states comprises a TCI state associated with a bit with a value that indicates that the TCI state corresponds to one of the N reference signal elements.
The method of claim 18, wherein a signaled TCI state of the one or more signaled TCI states comprises a quasi-colocation reference signal (QCL-RS) with a corresponding synchronization signal block (SSB) , wherein the corresponding SSB is not within a time window or is not within an SSB pool.
The method of claim 23, wherein the corresponding SSB is quasi-colocated with the QCL-RS with respect to a first type of channel property or a second type of channel property.
The method of claim 23, wherein the time window is based on a time of the control message and a predefined time duration.
The method of any of claims 18 to 25, wherein a signaled TCI state of the one or more signaled TCI states is at least one of a new TCI state, an unknown TCI state, a TCI state comprising a quasi-colocation reference signal (QCL-RS) with a period that is greater than a predefined duration, a TCI state configured with a parameter of one of the N reference signal elements, a TCI state associated with a bit with a value that indicates that the TCI state corresponds to another of the N reference signal elements, or a TCI state comprising a QCL-RS with a corresponding synchronization signal block (SSB) that is not within a time window or not in an SSB pool.
The method of any of claims 18 to 26, wherein N is based on a number of the one or more signaled TCI states in the control message.
The method of claim 27, wherein upon a determination that a first signaled TCI state and a second signaled TCI state satisfy a condition, the number of signaled TCI states in the control message only accounts for the first signaled TCI state.
The method of claim 28, wherein the condition comprises the first and second signaled TCI states corresponding to a same SSB or the QCL-RS of the first and second signaled TCI states being quasi-colocated.
The method of any of claims 18 to 29, wherein each of the N reference signal elements corresponds to a respective signaled TCI state of the one or more signaled TCI states.
The method of claim 30, wherein a parameter of the N reference signal elements is based on a first N reference signal element configurations in a predefined reference signal element configuration list, and wherein each of the N reference signal elements is mapped to one of the first N reference signal element configurations.
The method of claim 30, wherein one or more quasi-colocation reference signals (QCL-RSs) of one of the N reference signal elements is based on one or more QCL-RSs in the signaled TCI state corresponding to the reference signal element.
The method of claim 30, wherein a parameter of one of the N reference signal elements is based on a parameter of one or more quasi-colocation reference signals (QCL-RSs) included in the signaled TCI state corresponding to the reference signal element.
The method of claim 30, wherein a parameter of one of the N reference signal elements is based on a configured parameter associated with the signaled TCI state corresponding to the reference signal element.
The method of any of claims 18 to 34, wherein a number of the one or more signaled TCI states is N, and wherein the one or more signaled TCI states are included in a TCI state list in the control message.
The method of claim 35, wherein each of the N reference signal elements corresponds to a signaled TCI state of the N signaled TCI states, and wherein each of the N signaled TCI states corresponds to a reference signal element of the N reference signal elements.
The method of claim 31, 33 or 34, wherein the parameter comprises at least one of a sequence parameter, a time-domain resource parameter, a frequency-domain resource parameter, a power parameter, a repetition parameter, or a quasi-colocation reference signal (QCL-RS) parameter.
The method of any of claims 1 to 3, wherein the configuration indication comprises a bit indicating whether the control message triggers at least one of the N reference signal elements.
The method of any of claims 1 to 38, wherein the control message comprises a downlink control information (DCI) or a medium access control (MAC) control element (CE) .
The method of any of claims 18 to 38, wherein a signaled TCI state corresponding to one of the N reference signal elements starts to be applied after the reference signal element, and wherein the signaled TCI state is included in the one or more signaled TCI states.
The method of any of claims 18 to 38, wherein a signaled TCI state corresponding to one of the N reference signal elements starts to be applied a predefined duration after the reference signal element, and wherein the signaled TCI states is included in the one or more signaled TCI states.
The method of any of claims 18 to 38, wherein the one or more signaled TCI states start to be applied after the N reference signal elements.
A method of wireless communication, comprising:

receiving, by a wireless terminal, a control message comprising N signaled Transmission Configuration Indication (TCI) states, wherein N is a positive integer; and

determining, based on one or more reference signal elements, a time unit from which one or more signaled TCI states of the N signaled TCI states are starting to be applied.
A method of wireless communication, comprising:

transmitting, by a network node to a wireless device, a control message comprising N signaled Transmission Configuration Indication (TCI) states, wherein N is a positive integer;

determining, based on one or more reference signal elements, a time unit from which one or more signaled TCI states of the N signaled TCI states are starting to be applied; and

transmitting, to the wireless device, a channel or a signal with a signaled TCI state of the N signal TCI states from the time unit.
The method of claim 43 or 44, wherein the time unit is a time unit from which one signaled TCI state of the N signaled TCI states starts to be applied.
The method of claim 45, wherein the time unit is a time unit after a predefined time duration after a reference signal element of the one or more reference signal elements, and wherein the reference signal element corresponds to the one signaled TCI state.
The method of claim 43 or 44, wherein the time unit is a time unit from which the N signaled TCI states start to be applied, and wherein all of the N signaled TCI states start to be applied at a same time.
The method of claim 43 or 44, wherein the time unit is a time unit after a predefined time duration after the one or more reference signal elements.
The method of any of claim 43 to 48, wherein a signaled TCI state of the N signaled TCI states comprises at least one of a new TCI state, a TCI state in a first mode, a TCI state comprising a quasi-colocation reference signal (QCL-RS) with a period that is greater than a predefined duration, a TCI state configured with a parameter of the reference signal element, a TCI state associated with a one-valued bit that indicates whether the TCI state corresponds to the reference signal element, a TCI state comprising a QCL-RS with a corresponding synchronization signal block (SSB) that is not within a time window, or a TCI state comprising a QCL-RS with a corresponding SSB that is not within an SSB pool.
The method of any of claims 43 to 48, wherein the one or more reference signal elements comprises a reference signal element triggered by the control message.
The method of any of claims 43 to 48, wherein the one or more reference signal elements comprises a reference signal element not triggered by the control message.
The method of claim 51, wherein the one or more reference signal elements comprises the reference signal element not triggered by the control message and a reference signal element triggered by the control message.
The method of any of claims 43 to 48, wherein the one or more reference signal elements comprises a reference signal resource or a reference signal resource set.
The method of claim 53, wherein the reference signal resource comprises a channel state information reference signal (CSI-RS) resource or a synchronization signal block (SSB) resource.
The method of any of claims 43 to 48, wherein a number of the one or more reference signal elements is based on a value of N.
The method of any of claims 43 to 48, wherein each of the one or more reference signal elements corresponds to a signaled TCI state of the N signaled TCI states.
A wireless communications apparatus comprising a processor and a memory, wherein the processor is configured to read code from the memory and implement a method recited in any of claims 1 to 56.
A computer program product comprising a computer-readable program medium code stored thereupon, the code, when executed by a processor, causing the processor to implement a method recited in any of claims 1 to 56.