WO2024000441A1

WO2024000441A1 - Multi-cell scheduling and transmission for wireless communications

Info

Publication number: WO2024000441A1
Application number: PCT/CN2022/102923
Authority: WO
Inventors: Jing Shi; Xianghui HAN; Shuaihua KOU; Kai Xiao
Original assignee: Zte Corporation
Priority date: 2022-06-30
Filing date: 2022-06-30
Publication date: 2024-01-04
Also published as: CN117643150A

Abstract

This document generally relates to wireless communication involving a network device that transmits a multi-cell downlink control information (MC-DCI) for scheduling a plurality of co-scheduled cells in one or more search spaces, and a user device that detects the MC-DCI in the one or more search spaces. Additionally, the user device and the network device communicate, such as by transmitting and/or receiving, at least one traffic channel on at least one co-scheduled cell according to a co-scheduled cells indicator in the MC-DCI.

Description

MULTI-CELL SCHEDULING AND TRANSMISSION FOR WIRELESS COMMUNICATIONS

TECHNICAL FIELD

This document is directed generally to wireless communication that involves multi-cell downlink control information (MC-DCI) transmission.

BACKGROUND

In current carrier aggregation (CA) , the scheduling mechanism used for wireless communication only allows scheduling a single-cell traffic channel per a scheduling downlink control information (DCI) . However, a need to have simultaneous scheduling of multiple cells may increase with more available scattered spectrum bands. Ways to optimally determine search spaces and corresponding blind decode (BD) and control channel element (CCE) counts may be desirable.

SUMMARY

This document relates to methods, systems, apparatuses and devices for wireless communication. In some implementations, a method for wireless communication includes: detecting, by a user device, a multi-cell downlink control information (MC-DCI) for scheduling a plurality of co-scheduled cells in one or more search spaces; and communicating, by the user device, at least one traffic channel on at least one actual co-scheduled cell according to a co-scheduled cells indicator in the MC-DCI.

In some other implementations, a method for wireless communication includes: transmitting, by a network device, a MC-DCI for scheduling a plurality of co-scheduled cells in one or more search spaces; and communicating, by the network device, at least one traffic channel on at least one actual co-scheduled cell according to a co-scheduled cells indicator in the MC-DCI.

In some other implementations, a device, such as a network device, is disclosed. The device may include one or more processors and one or more memories, wherein the one or more processors are configured to read computer code from the one or more memories to implement any of the methods above.

In yet some other implementations, a computer program product is disclosed. The computer program product may include a non-transitory computer-readable program medium with computer code stored thereupon, the computer code, when executed by one or more processors, causing the one or more processors to implement any of the methods above.

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 a block diagram of an example of a wireless communication system.

FIG. 2 shows a diagram of a plurality of co-scheduled cells for multi-cell scheduling that includes a multi-cell downlink control information (MC-DCI) transmitted on a scheduling cell.

FIG. 3 shows a flow chart of an example method of wireless communication for MC-DCI transmission.

FIG. 4 shows a flow chart of another example method of wireless communication for MC-DCI transmission.

FIG. 5 shows a diagram of a plurality of co-scheduled cells for multi-cell scheduling that includes a MC-DCI and a single-cell DCI (SC-DCI) transmitted on a scheduling cell.

FIG. 6 shows a diagram of a plurality of co-scheduled cells for multi-cell scheduling that includes a MC-DCI transmitted on a first scheduling cell and a SC-DCI transmitted on a second scheduling cell.

FIG. 7 shows a diagram of a plurality of co-scheduled cells for multi-cell scheduling that includes a first MC-DCI transmitted on a primary cell (PCell) and a second MC-DCI transmitted on a secondary cell (SCell) , where scheduling is not performed with PCell-scheduled-by-SCell scheduling.

FIG. 8 shows a diagram of a plurality of co-scheduled cells for multi-cell scheduling that includes a SC-DCI transmitted on a PCell for PCell self-scheduling, and a MC-DCI transmitted on a scheduling Scell (sSCell) for PCell-scheduled-by-SCell scheduling.

FIG. 9 shows a diagram of a plurality of co-scheduled cells for multi-cell scheduling that includes a first MC-DCI transmitted on a PCell for PCell self scheduling, and a second MC-DCI transmitted on a sSCell for PCell-scheduled-by-SCell scheduling.

FIG. 10 shows a diagram of a plurality of co-scheduled cells for multi-cell scheduling that includes a first MC-DCI transmitted on a PCell for PCell self scheduling, and a second MC-DCI transmitted on a sSCell for PCell-scheduled-by-SCell scheduling, where the second MC-DCI is also transmitted to schedule the sSCell.

DETAILED DESCRIPTION

The present description describes various embodiments of systems, apparatuses, devices, and methods for wireless communications involving multi-cell downlink control information (MC-DCI) communication.

Fig. 1 shows a diagram of an example wireless communication system 100 including a plurality of communication nodes (or just nodes) that are configured to wirelessly communicate with each other. In general, the communication nodes include at least one user device 102 and at least one network device 104. The example wireless communication system 100 in Fig. 1 is shown as including two user devices 102, including a first user device 102 (1) and a second user device 102 (2) , and one device 104. However, various other examples of the wireless communication system 100 that include any of various combinations of one or more user devices 102 and/or one or more network devices 104 may be possible.

In general, a user device as described herein, such as the user device 102, may include a single electronic device or apparatus, or multiple (e.g., a network of) electronic devices or apparatuses, capable of communicating wirelessly over a network. A user device may comprise or otherwise be referred to as a user terminal, a user terminal device, or a user equipment (UE) . Additionally, a user device may be or include, but not limited to, a mobile device (such as a mobile phone, a smart phone, a smart watch, a tablet, a laptop computer, vehicle or other vessel (human, motor, or engine-powered, such as an automobile, a plane, a train, a ship, or a bicycle as non-limiting examples) or a fixed or stationary device, (such as a desktop computer or other computing device that is not ordinarily moved for long periods of time, such as appliances, other relatively heavy devices including Internet of things (IoT) , or computing devices used in commercial or industrial environments, as non-limiting examples) . In various embodiments, a user device 102 may include transceiver circuitry 106 coupled to an antenna 108 to effect wireless communication with the network device 104. The transceiver circuitry 106 may also be coupled to a processor 110, which may also be coupled to a memory 112 or other storage device. The memory 112 may store therein instructions or code that, when read and executed by the processor 110, cause the processor 110 to implement various ones of the methods described herein.

Additionally, in general, a network device as described herein, such as the network device 104, may include a single electronic device or apparatus, or multiple (e.g., a network of) electronic devices or apparatuses, and may comprise one or more wireless access nodes, base stations, or other wireless network access points capable of communicating wirelessly over a network with one or more user devices and/or with one or more other network devices 104. For example, the network device 104 may comprise a 4G LTE base station, a 5G NR base station, a 5G central-unit base station, a 5G distributed-unit base station, a next generation Node B (gNB) , an enhanced Node B (eNB) , or other similar or next-generation (e.g., 6G) base stations, in various embodiments. A network device 104 may include transceiver circuitry 114 coupled to an antenna 116, which may include an antenna tower 118 in various approaches, to effect wireless communication with the user device 102 or another network device 104. The transceiver circuitry 114 may also be coupled to one or more processors 120, which may also be coupled to a memory 122 or other storage device. The memory 122 may store therein instructions or code that, when read and executed by the processor 120, cause the processor 120 to implement one or more of the methods described herein.

In various embodiments, two communication nodes in the wireless system 100-such as a user device 102 and a network device 104, two user devices 102 without a network device 104, or two network devices 104 without a user device 102-may be configured to wirelessly communicate with each other in or over a mobile network and/or a wireless access network according to one or more standards and/or specifications. In general, the standards and/or specifications may define the rules or procedures under which the communication nodes can wirelessly communicate, which, in various embodiments, may include those for communicating in millimeter (mm) -Wave bands, and/or with multi-antenna schemes and beamforming functions. In addition or alternatively, the standards and/or specifications are those that define a radio access technology and/or a cellular technology, such as Fourth Generation (4G) Long Term Evolution (LTE) , Fifth Generation (5G) New Radio (NR) , or New Radio Unlicensed (NR-U) , as non-limiting examples.

Additionally, in the wireless system 100, the communication nodes are configured to wirelessly communicate signals between each other. In general, a communication in the wireless system 100 between two communication nodes can be or include a transmission or a reception, and is generally both simultaneously, depending on the perspective of a particular node in the communication. For example, for a given communication between a first node and a second node where the first node is transmitting a signal to the second node and the second node is receiving the signal from the first node, the first node may be referred to as a source or transmitting node or device, the second node may be referred to as a destination or receiving node or device, and the communication may be considered a transmission for the first node and a reception for the second node. Of course, since communication nodes in a wireless system 100 can both send and receive signals, a single communication node may be both a transmitting/source node and a receiving/destination node simultaneously or switch between being a source/transmitting node and a destination/receiving node.

Also, particular signals can be characterized or defined as either an uplink (UL) signal, a downlink (DL) signal, or a sidelink (SL) signal. An uplink signal is a signal transmitted from a user device 102 to a network device 104. A downlink signal is a signal transmitted from a network device 104 to a user device 102. A sidelink signal is a signal transmitted from a one user device 102 to another user device 102, or a signal transmitted from one network device 104 to a another network device 104. Also, for sidelink transmissions, a first/source user device 102 directly transmits a sidelink signal to a second/destination user device 102 without any forwarding of the sidelink signal to a network device 104.

Additionally, signals communicated between communication nodes in the system 100 may be characterized or defined as a data signal or a control signal. In general, a data signal is a signal that includes or carries data, such multimedia data (e.g., voice and/or image data) , and a control signal is a signal that carries control information that configures the communication nodes in certain ways in order to communicate with each other, or otherwise controls how the communication nodes communicate data signals with each other. Also, certain signals may be defined or characterized by combinations of data/control and uplink/downlink/sidelink, including uplink control signals, uplink data signals, downlink control signals, downlink data signals, sidelink control signals, and sidelink data signals.

For at least some specifications, such as 5G NR, data and control signals are transmitted and/or carried on physical channels. Generally, a physical channel corresponds to a set of time-frequency resources used for transmission of a signal. Different types of physical channels may be used to transmit different types of signals. For example, physical data channels (or just data channels) , also herein called traffic channels, are used to transmit data signals, and physical control channels (or just control channels) are used to transmit control signals. Example types of traffic channels (or physical data channels) include, but are not limited to, a physical downlink shared channel (PDSCH) used to communicate downlink data signals, a physical uplink shared channel (PUSCH) used to communicate uplink data signals, and a physical sidelink shared channel (PSSCH) used to communicate sidelink data signals. In addition, example types of physical control channels include, but are not limited to, a physical downlink control channel (PDCCH) used to communicate downlink control signals, a physical uplink control channel (PUCCH) used to communicate uplink control signals, and a physical sidelink control channel (PSCCH) used to communicate sidelink control signals. As used herein for simplicity, unless specified otherwise, a particular type of physical channel is also used to refer to a signal that is transmitted on that particular type of physical channel, and/or a transmission on that particular type of transmission. As an example illustration, a PDSCH refers to the physical downlink shared channel itself, a downlink data signal transmitted on the PDSCH, or a downlink data transmission. Accordingly, a communication node transmitting or receiving a PDSCH means that the communication node is transmitting or receiving a signal on a PDSCH.

Additionally, for at least some specifications, such as 5G NR, and/or for at least some types of control signals, a control signal that a communication node transmits may include control information comprising the information necessary to enable transmission of one or more data signals between communication nodes, and/or to schedule one or more data channels (or one or more transmissions on data channels) . For example, such control information may include the information necessary for proper reception, decoding, and demodulation of a data signals received on physical data channels during a data transmission, and/or for uplink scheduling grants that inform the user device about the resources and transport format to use for uplink data transmissions. In some embodiments, the control information includes downlink control information (DCI) that is transmitted in the downlink direction from a network device 104 to a user device 102. In other embodiments, the control information includes uplink control information (UCI) that is transmitted in the uplink direction from a user device 102 to a network device 104, or sidelink control information (SCI) that is transmitted in the sidelink direction from one user device 102 (1) to another user device 102 (2) .

In addition, for at least some configurations, including some using 4G and 5G, for carrier aggregation (CA) , the scheduling mechanism used in the wireless communication system 100, such as by the user device 102 and the network device 104, allows scheduling single-cell traffic channels (e.g., PUSCH/PDSCH) per one scheduling DCI. Such a single DCI configured to schedule only one cell is referred to as a single-cell DCI (SC-DCI) . In order to reduce control overhead while performing simultaneous scheduling in multiple cells, multi-cell scheduling traffic channel scheduling may be performed using a single scheduling DCI. Such a single DCI that schedules in multiple cells is referred to as a multi-cell DCI (MC-DCI) . A MC-DCI effectively merges multiple DCIs used for each scheduled cell into a single DCI.

In a first case (Case 1) for multi-cell scheduling, one scheduled cell is, or can be, configured with a single scheduling cell. Herein, the term scheduling cell refers to a cell in or on which a DCI is transmitted and/or detected. Fig. 2 shows a schematic diagram illustrating an example of the first case for multi-cell scheduling. In the example in Fig. 2, Cell 1 is a scheduling cell in which a MC-DCI is communicated (transmitted and received/detected) to schedule a traffic channel PxSCH in each of a plurality of co-scheduled cells Cell 1, Cell 2, Cell 3, and Cell 4. That is, MC-DCI is communicated to schedule traffic channel PxSCH 1 in Cell 1, traffic channel PxSCH 2 in Cell 2, traffic channel PxSCH 3 in Cell 3, and traffic channel PxSCH 4 in Cell 4. PxSCH is used to denote either a PDSCH or a PUSCH. Also, in Case 1, at least one of the devices in the wireless communication system (e.g., at least one of the user device 102 or the network device 104) , may count a number of blind decodes (BDs) and/or a number of control channel elements (CCEs) . That is, at least one device in the wireless communication system 100 (e.g., at least one of the user device 102 or the network device 104) may know a maximum number

of monitored PDCCH candidates per slot or span (e.g., a span of symbols) for a downlink (DL) bandwidth part (BWP) with a sub-carrier spacing (SCS) configuration P∈^0, 1, 2, 3` for a single serving cell. In addition, the user device 102 may keep track of a blind decode (BD) count. Each time a user device 102 blindly detects or decodes, or at least attempts to detect or decode, or otherwise monitors a PDCCH candidate carrying a DCI (e.g., a MC-DCI) per such a slot/span, the user device 102 may increase a BD count, and may be configured to perform a number of blind decodes up to the maximum number

In addition or alternatively, at least one device in the wireless communication system 100 (e.g., at least one of the user device 102 or the network device 104) may know a maximum number

of non-overlapped CCEs that the user device 102 can monitor per slot/span for a DL BWP with a SCS configuration P∈^0, 1, 2, 3` for a single serving cell. Each time a user device 102 identifies a CCE in such a slot/span, the user device 102 may increase a CCE count, and may be configured to not to identify more than the maximum number

Additionally, in various embodiments for Case 1, the user device 102 may perform (e.g., by incrementing) a BD count or a CCE count according to one of various options. In a first option (Option 1) , the user device 102 may perform a BD count and/or a CCE count in each scheduled cell. That is, the user device 102 counts the blind decodes and/or the CCEs of the PDCCHs carrying the MC-DCIs transmitted on the scheduling cell in each UE-specific search space (USS) corresponding to each scheduled cell. In a second option (Option 2) , the user device 102 may count blind decodes and/or CCEs in only one scheduled cell. That is, the user device 102 may count blind decodes and/or CCEs of PDCCHs carrying MC-DCIs transmitted on the scheduling cell in a USS corresponding to only one scheduled cell. A third option (Option 3) is similar to the first option, except that the user device 102 scales the BD and/or CCE counting according to the number of co-scheduled cells. In a fourth option (Option 4) , the user device 102 counts BDs and/or CCEs for the scheduling cell instead of for each of the scheduled cells.

In at least some examples, the maximum number

of monitored PDDCH candidates per slot/span for a DL BWP with a SCS configuration P∈^0, 1, 2, 3` for a single serving cell is determined according to the below Table 1, where P∈^0, 1, 2, 3` corresponds to 15 kiloHertz (kHz) , 30 kHz, 60 kHz, and 120 kHz, respectively.

Table 1

Also, in at least some examples, the maximum number

of non-overlapped CCEs per slot/span for a DL BWP with a SCS configuration P∈^0, 1, 2, 3` for a single serving cell is determined according to the below Table 2.

Table 2

Additionally, in various embodiments, if a user device 102 is configured with

downlink cells with DL BWPs having a given SCS configuration P, where

where a DL BWP of an activated cell is the active DL BWP of the activated cell, and a DL BWP of a deactivated cell is the DL BWP with index provided by firstActiveDownlinkBWP-Id for the deactivated cell, the user device 102 may not be required to monitor more than

PDCCH candidates or more than

non-overlapped CCEs per slot on the active DL BWP (s) of the scheduling cell (s) from the

downlink cells.

Also, in at least some embodiments, a user device 102 has a DCI size budget per serving cell. For at least some implementations of such a DCI size budget, the maximum total number of different DCI sizes that the user device 102 monitors or handles is not more than 4 per cell, and/or the maximum total number of different DCI sizes with Cell Radio Network Temporary Identifier (C-RNTI) that the user device 102 is configured to monitor or handle is not more than 3 per cell.

Fig. 3 is a flow chart of an example method 300 of wireless communication for MC-DCI transmission. At block 302, a user device 102 may detect a MC-DCI for scheduling a plurality of co-scheduled cells. At block 304, the user device 102 may communicate, such as by receiving and/or transmitting, at least one traffic channel on at least one actual co-scheduled cell according to a co-scheduled cells indicator in the MC-DCI.

Fig. 4 is a flow chart of another example method 400 of wireless communication for MC-DCI transmission. At block 402, a network device 104 may transmit a MC-DCI for scheduling a plurality of co-scheduled cells in one or more search spaces. At block 404, the network device may communicate, such as by receiving and/or transmitting, at least one traffic channel on at least one co-scheduled cell according to a co-scheduled cells indicator in the MC-DCI.

As used herein, the plurality of co-scheduled cells scheduled by a MC-DCI may be cells that can be, or are capable of being, scheduled by one or the same MC-DCI. An actual co-scheduled cell is a cell that is actually being scheduled by the MC-DCI. Also, a co-scheduled cells indicator included in a MC-DCI indicates which of the plurality of co-scheduled cells are the actual co-scheduled cells, i.e., are actually being scheduled by the MC-DCI.

To briefly illustrate as an example, suppose four cells are capable of being scheduled by a MC-DCI, including Cell 1, Cell 2, Cell 3, and Cell 4. In event that a given MC-DCI schedules Cell 1 and Cell 2 but not Cell 3 and Cell 4,

Cells

1 and 2 are the actual co-scheduled cells, and the co-scheduled cells indicator has a value that indicates Cell 1 and Cell 2, but not Cell 3 and Cell 4. In this example, at

blocks

302 and 402, the user device 302 may detect, and the network device 104 may transmit, a MC-DCI that has a co-scheduled cells indicator that indicates Cell 1 and Cell 2. In turn, at

blocks

304 and 404, the user device 102 and the network device 104 communicate at least one traffic channel according to the co-scheduled cells

indicator indicating Cells

1 and 2, such as by the user device 102 transmitting and the network device 104 receiving a PUSCH, or the user device 102 receiving and the network device 104 transmitting a PDSCH, on

Cells

1 and 2.

Additionally, in some embodiments of the method 300 and/or the method 400, a MC-DCI that is transmitted may include a co-scheduled cells indicator that indicates a combination of one more co-scheduled cells scheduled, or to be scheduled, by the MC-DCI. For a given MC-DCI, the co-scheduled cells indicator may have one of a plurality of values, with each value corresponding to a unique or different combination of one or more co-scheduled cells. For example, the co-scheduled cells indicator values may be n-bit values, where each n-bit value corresponds to a different combination. For a given MC-DCI having a co-scheduled cells indicator having a particular value, the co-scheduled cells in the combination corresponding to the particular value are the actual co-scheduled cells.

Also, in various embodiments of the method 300 and/or the method 400, the plurality of possible co-schedule cells indicator values that may be included in or indicated by a MC-DCI may be embodied in or represented by a co-scheduled cells indictor table or other data structure, which devices in the wireless communication system 100 may access or use to generate, communicate, and/or process MC-DCIs. For example, a given co-scheduled cells indicator value in or for a MC-DCI may point to a particular row in such a co-scheduled cells indicator table. In addition or alternatively, a co-scheduled cells indicator table may be configured by RRC signaling. Table 3, below, provides an example co-scheduled cells indicator table of co-scheduled cell indicator values and corresponding combinations of one or more actual co-scheduled cells.

co-scheduled cells indicator

CIF Value combination

000	0
001	1
010	2
011	3
100	0, 1
101	2, 3
110	0, 1, 2
111	0, 1, 2, 3

Table 3: Code-point indicator for the co-scheduled cells

In the example corresponding to Table 3, the maximum number of co-scheduled cells that can be scheduled by a MC-DCI is four, including Cell 0, Cell 1, Cell 2, and Cell 3. Additionally, the example in Table 3 shows each co-scheduled cells indicator having a unique or different 3-bit value, each corresponding to a different combination of actual co-scheduled. Accordingly, for example, a MC-DCI having a co-scheduled cells indicator of ‘101’ indicates that the combination of

Cells

2 and 3 are the actual co-scheduled cell being scheduled by the MC-DCI.

Additionally, in various embodiments, such as the example indicated by Table 3, each co-scheduled indicator value and associated co-scheduled cell combination may correspond to a respective one of a plurality of carrier indicator field (CIF) values. For example, in Table 3, each co-scheduled cell indicator value and corresponding co-scheduled cell combination corresponds to a respective one of CIF values 1 to 7.

In addition or alternatively, in various embodiments, correspondences between co-scheduled cell indicator values, co-scheduled cell combinations, CIF values, and/or a co-scheduled cell indicator table organizing or representing the values and co-scheduled cell combinations may be configured according to at least one of the following schemes.

In a first scheme, a scheduling cell may be configured with a co-scheduled cell indicator table. For example, if schedulingCellInfo = own (which means that the cell is a scheduling cell) , then the co-scheduled cell indicator table is configured in the scheduling cell for scheduling a set of scheduled cells, or the scheduling cell may be provided with the rows indicating the correspondences, from which the scheduling cell may generate or derive the co-scheduled cells indicator table.

In a second scheme, each co-scheduled cell is configured with only those rows of a co-scheduled cells indicator table for which the co-scheduled cell is at least part of the combination of one or more of the plurality of co-scheduled cells indicated by the row. For example, if schedulingCellInfo = other for a given scheduled cell, then for this scheduled cell, partial rows including the scheduled cell of the co-scheduled cells table are configured for this scheduled cell. For example, suppose the co-scheduled cells indicator Table 3 has or corresponds to code-points or row indices 0-7, where each code-point or row index points or corresponds to one of the 8 rows in Table 3. Accordingly, code-points or

row indices

1, 4, 6, 7 are configured for Cell 1 since Cell 1 is part of the combinations for those rows. Similarly, code-points or row indices 2, 5, 6, 7 are configured for Cell 2 since Cell 2 is part of the combinations for those rows.

In a third scheme, a co-scheduled cells indicator table is configured in a cell group. For example, a configuration of the co-scheduled cells indicator table is configured in the CellGroupConfig, the MAC-CellGroupConfig, and/or the PhysicalCellGroupConfig.

After a device in the wireless communication system 100 (e.g., the network device 102 or the user device 102) configures a co-scheduled cells indicator table, the network device 104 and the user device 102 may communicate one or more MC-DCIs to schedule multiple cells according each row of the co-scheduled cells indicator table.

Additionally, in various embodiments of the method 300 and/or the method 400, in event that a PDSCH is scheduled and/or communicated on each co-scheduled cell by a MC-DCI, when the user device 102 detects the MC-DCI (e.g. having DCI format 1_X) scheduling a set of co-scheduled PDSCHs, the user device 102 provides corresponding hybrid automatic repeat request acknowledgement (HARQ-ACK) information in a PUCCH transmission within uplink (UL) slot n+k, where k is a number of slots and is indicated by the PDSCH-to-HARQ feedback timing indicator field in the DCI format and n is the last UL slot that overlaps with the DL slot n _D for the reference PDSCH reception. The network device 104 and/or the user device 102 may determine the reference PDSCH among the configured maximum co-scheduled cells or the actual co-scheduled cells according to one of the following schemes. In a first scheme, the last PDSCH of the multi- PDSCH on the co-scheduled cells is the reference PDSCH. In a second scheme, a PDSCH on a predefined or configured cell (e.g., a cell having the lowest cell index among the co-scheduled cells) is the reference PDSCH. For at least some embodiments where the reference PDSCH is determined among the configured maximum co-scheduled cells, and the cell carrying the reference PDSCH is deactivated or dormant, the reference PDSCH may be re-selected or determined among the actual co-scheduled cells according to the first or second schemes.

In addition or alternatively, for at least some embodiments of the method 300 and/or the method 400, for a PDCCH carrying a MC-DCI on a scheduling cell, where the MC-DCI is transmitted for scheduling a plurality of co-scheduled cells, the user device 102 may count blind decodes or non-overlapped CCEs in each co-scheduled cell, such as in each UE-specific search space (USS) corresponding to each of the co-scheduled cells.

In addition or alternatively, suppose for example that a given ith co-scheduled cell, Cell i, is scheduled by the MC-DCI, and the user device 102 detects the MC-DCI in the USS of Cell i. In turn, the user device 102 may count the size of MC-DCI and/or count the blind decode and/or the non-overlapped CCEs of the MC-DCI for Cell i with or without scaling. In event that Cell i is not scheduled by the MC-DCI and the user device 102 detects the MC-DCI in the USS of Cell i, the user device 102 may determine, or otherwise be configured to determine, whether to count blind decodes, non-overlapped CCEs, and/or MC-DCI sizes for Cell i. As examples, using the co-scheduled cells indicator Table 3 above to illustrate, Cell 0 is scheduled by an MC-DCI having any of co-scheduled cells indicator values { ‘000’ , ‘100’ , ‘110’ , ‘111’ } . Upon detection of the MC-DCI, the user device 102 may perform counting in Cell 0 with or without scaling. However, if a MC-DCI has a co-scheduled cells indicator value that does not indicate that Cell 0 is scheduled { ‘001’ , ‘010’ , ‘011’ , ‘101’ } , the user device may determine to count for Cell 0 according to one of the following schemes.

In a first scheme, the network device 104 may transmit the MC-DCI and/or the user device 102 may detect the MC-DCI in a search space (e.g., a USS) of an actual co-scheduled cell according to the value of the co-scheduled cells indicator. Correspondingly, when the user device 102 detects the MC-DCI at block 302 and/or the network device 104 transmits the MC-DCI at block 402 in the one or more search spaces, a search space of the one or more search spaces is a search space of an actual co-scheduled as indicated by, or according to, the co-scheduled cells indicator. For at least some of these embodiments of the first scheme, the network device 104 may transmit the MC-DCI and/or the user device 102 may detect the MC-DCI in the USS of a co-scheduled cell on condition that the co-scheduled cells indicator in the MC-DCI indicates the co-scheduled cell. For example, the network device 104 may not transmit a MC-DCI in the USS of Cell 0 if the co-scheduled cells indicator in the MC-DCI does not have a value that indicates Cell 0 as an actual co-scheduled cell. In addition, the user device 102 may not detect a MC-DCI in the USS of Cell 0 if the MC-DCI does not have a value that indicates Cell 0 as an actual co-scheduled cell.

In a second scheme, the network device 104 may transmit the MC-DCI and/or the user device 102 may detect the MC-DCI in a search space (e.g., a USS) of any of the plurality of co-scheduled cells (not necessarily just an actual co-scheduled cell) . For at least some of these embodiments of the second scheme, the network device 104 may transmit the MC-DCI and/or the user device 102 may detect the MC-DCI in a search space of the plurality of co-scheduled cells in event that, or on condition that, search space sharing is configured or supported for the plurality of co-scheduled cells scheduled by the MC-DCI. In general, search space sharing allows for transmission and detection in search spaces of cells other than the cell for which a DCI is scheduling. For example, if search space sharing is not supported, then a DCI for scheduling a given ith cell, Cell i, can only be transmitted and detected in the search space of Cell i. As another example, if search space sharing is supported such as by Cell i and another cell, such as a jth cell Cell j , then a DCI for scheduling Cell i can be transmitted and detected in a search space of Cell i, as well as transmitted and detected in a search space of one or more other cells supporting search space sharing, such as a Cell j. In addition, for at least some embodiments of the second scheme, the user device 102 may count blind decodes and/or non-overlapped CEEs, with or without scaling, when detecting the MC-DCI. In addition or alternatively, capability of search space sharing may be in the uplink direction and/or the downlink direction, such as through use of MC-schedulingSearchSpaceSharingDL or MC-schedulingSearchSpaceSharingUL. One advantage of the second scheme is that, as long as the co-scheduled cells support search space sharing, the MC-DCI can be transmitted and/or detected, regardless of the value of the co-scheduled cells indicator, including regardless of whether the value indicates a cell being scheduled or not.

In a third scheme, the network device 104 may transmit the MC-DCI and/or the user device 102 may detect the MC-DCI in a search space (e.g., a USS) of the scheduling cell if a carrier indicator number is zero (0) , or exceeds (or is larger than) a predetermined value, such as 7.

In a fourth scheme, the co-scheduled cells indicator may replace the carrier indicator number (N _CI) , and the co-scheduled cells indicator values may indicate to the user device 102 how to perform counting for the plurality of co-scheduled cells. As an example, using Table 3, co-scheduled cells indicator values { ‘000’ , ‘001’ , ‘010’ , ‘011’ } may indicate or cause the user device 102 to count blind decodes and/or non-overlapped CCEs for each scheduled cell; and co-scheduled cells indicator values { ‘100’ , ‘101’ , ‘110’ , and ‘111’ } may indicate or cause the user device 102 to count blind decodes and/or non-overlapped CCEs only for the actual co-scheduled cells indicated by the values or for the scheduling cell.

Also, for at least some embodiments of the method 300 and/or the method 400, the monitored DCI formats that the user device 102 monitors in a first UE-specific search space (USS) for a co-scheduled cell are determined or configured according to the monitored DCI formats that the user device 102 monitors in a second USS of the scheduling cell, where the first and the second USS have the same USS identification (ID) .

In addition or alternatively, in event that the network device 104 transmits the MC-DCI on a scheduling cell that does not support self-scheduling, or in event that the user device 102 reports that it only supports detecting SC-DCI, then the MC-DCI formats that the user device 102 detects may be determined according to one of the following schemes.

In a first scheme (Scheme 1) , the MC-DCI formats that the user device 102 detects is configured per USS per scheduled cell, besides USS id and nrofCandidates (number of candidates of each aggregation level) . MC-DCI formats that the user device 102 detects may also be configured in the USS of the scheduled cell for embodiments that perform cross carrier scheduling.

In a second scheme (Scheme 2) , the MC-DCI formats that the user device 102 detects is only configured in the USS of the scheduling cell, regardless of whether the scheduling cell can be scheduled by the MC-DCI transmitted on the scheduling cell.

In addition or alternatively, for at least some embodiments, the user device 102 may count blind decodes and/or non-overlapped CCEs in accordance with the transmission, detection, and/or counting schemes previously described. In addition or alternatively, different transmission, detection, and/or counting schemes may be employed for different scheduling capabilities. For example, the user device 102 may count blind decodes and/or non-overlapped CCEs differently for different sets of co-scheduled cells indicator values (Scheme 4 above) if the MC-DCI is transmitted on a scheduling cell that can perform self-scheduling, and may detect the MC-DCI for co-scheduled cells indicated by the co-scheduled cells indicator (Scheme 1 above) if the MC-DCI is transmitted on a scheduling cell that cannot perform self-scheduling.

Accordingly, one benefit may be that the MC-DCI can be transmitted/detected on scheduling cell in a USS of a scheduled cell according to the configuration of the DCI formats for the MC-DCI to be monitored in a USS, regardless of whether the scheduling cell can be scheduled by the MC-DCI transmitted on the scheduling cell.

In addition or alternatively, for at least some embodiments of the method 300 and/or the method 400, the user device 102 may count and/or determine a count for at least one of: a number of blind decodes, a number of non-overlapped CCEs, or a number of MC-DCI sizes for one of the plurality of co-scheduled cells. Correspondingly, the user device 102 may determine the co-scheduled cell for which to count. The user device 102 may do so in accordance with one of the following cell determination schemes.

In a first cell determination scheme, the user device 102 counts for or in the scheduled cell that is not configured with a SC-DCI. In general, when a cell is configured with a DCI, the user device 102 knows how many types of DCI formats of the DCI to detect for the cell. Correspondingly, when a cell not configured with a SC-DCI, the user device 102 does not know how many types of DCI formats of the SC-DCI to detect for the cell. As such, under the first cell determination scheme, the user device 102 may count for a co-scheduled cell for which the user device 102 does not know how many types of DCI formats of a SC-DCI to detect. In event the plurality of co-scheduled cells include multiple cells that are not configured with a SC-DCI, then the user device 102 may select or choose one of the multiple cells not configured with the SC-DCI. For at least some embodiments of the first cell determination scheme, the user device 102 may choose, from among the multiple cells not configured with the SC-DCI, the cell having the lowest cell index, a co-scheduled cell that is not configured with all single cell scheduling DCI formats, or a co- scheduled cell configured by radio resource control (RRC) signaling.

In a second cell determination scheme, the user device 102 may first determine to count in a co-scheduled cell that is not configured with a SC-DCI. If there are multiple (at least two) co-scheduled cells not configured with a SC-DCI, then the user device may determine to count in a co-scheduled cell configured with both a SC-DCI and the MC-DCI transmitted on a same scheduling cell.

Additionally, for at least some embodiments, such as for the first cell determination scheme or the second cell determination scheme, if the user device 102 determines or chooses a co-scheduled cell for which to count, and the co-scheduled cell is deactivated or dormant, the user device 102 may determine or choose a different one of the co-scheduled cells for which to count. For at least some of these embodiments, the different co-scheduled cell has a lowest cell index among activated cells of the plurality of co-scheduled cells, or is not configured with all single cell scheduling DCI formats (e.g., all of DCI format 0_1, 1_1, 0_2, and 1_2) .

Fig. 5 shows a diagram of a plurality of co-scheduled cells and only one scheduling cell to illustrate the cell determination schemes for counting for multi-cell scheduling. As shown in Fig. 5, the plurality of co-scheduled cells includes four cells: Cell 1, Cell 2, Cell 3, and Cell 4. In addition, Cell 1 is the scheduling cell on which a MC-DCI and a SC-DCI are transmitted. The MC-DCI is transmitted on Cell 1 to schedule a PxSCH 1 on Cell 1, a PxSCH 2 on Cell 2, a PxSCH 3 on Cell 3, and a PxSCH 4 on Cell 4 (where ‘x” can be either a U for uplink or D for downlink) . In addition, the SC-DCI is transmitted on Cell 1 to schedule a PxSCH 4 on Cell 4.

Fig. 6 shows a diagram of a plurality of co-scheduled cells and two scheduling cells to further illustrate the cell determination schemes for counting for multi-cell scheduling. As shown in Fig. 6, the plurality of co-scheduled cells includes four cells: Cell 1, Cell 2, Cell 3, and Cell 4. In addition, Cell 1 is a first scheduling cell on which a MC-DCI is transmitted, and Cell 4 is a second scheduling cell on which a SC-DCI is scheduled. The MC-DCI is transmitted on Cell 1 to schedule a PxSCH 1 on Cell 1, a PxSCH 2 on Cell 2, a PxSCH 3 on Cell 3, and a PxSCH 4 on Cell 4 (where ‘x” can be either a U for uplink or D for downlink) . In addition, the SC-DCI is transmitted on Cell 4 to schedule a PxSCH 4 on Cell 4.

Referring to either Fig. 5 or Fig. 6, under the first cell determination scheme, the user device 102 may determine the co-scheduled cell to count according to the cell that is not configured with a SC-DCI. In the examples in Figs. 5 and 6, the user device 102 may determine or choose the co-scheduled cell to be Cell 1, Cell 2, or Cell 3 (it would not choose Cell 4 since Cell 4 is configured with a SC-DCI) . Further, since there are multiple cells not configured with a SC-DCI, then the user device 102 may choose Cell 1 since that is the cell with the lowest cell index among Cell 1, Cell 2, and Cell 3. Alternatively, the user device 102 may choose the cell not configured with all single cell scheduling DCI formats (e.g., all of DCI formats 0_1, 1_1, 0_2, 1_2) . Alternatively, the user device 102 may choose the cell configured by RRC signaling. Under the second cell determination scheme, the user device 102 may first determine to count for a cell not configured with a SC-DCI (e.g., Cell 1, Cell 2, or Cell 3) . However, since there are multiple cells not configured with a SC-DCI, then for the configuration in Fig. 5, the user device 102 may determine to count for Cell 4 since that is a cell configured with both a MC-DCI and a SC-DCI transmitted on a same scheduling cell (i.e., Cell 1) . However, under the second cell determination scheme for Fig. 6, the user device 102 may determine not to count for Cell 4 since the MC-DCI and the SC-DCI are transmitted on different cells (Cell 1 for the MC-DCI and Cell 4 for the SC-DCI) .

Also, for at least some embodiments, in event that all of the co-scheduled cells are configured with a SC-DCI and a MC-DCI, then the user device 102 may count according to the multi-cell scheduling previously described with reference to Fig. 2.

Using the above-described counting, one benefit may be that in event both the MC-DCI and the SC-DCI are supported for a scheduled cell for the user device, the user device 102 may count the number of blind decodes, non-overlapped CCEs, and/or MC-DCI sizes in on scheduled cell, which may allow the user device 102 to not exceed a current DCI size budget or blind decode or non-overlapped CCE budget while also being able to support MC-DCI transmission.

In addition or alternatively, in at least some embodiments of method 300 and/or method 400, the user device 102 may count blind decodes, non-overlapped CCEs, and/or MC-DCI sizes with scaling. For example, user device 102 may perform counting for one or more of the co-scheduled cells, such as in accordance with the above-described schemes, and may scale one or more of the counts based on, or according to, a number of the co-scheduled cells. For at least some of these embodiments, the user device 102 may perform scaling using a scaling factor. In some embodiments, the scaling factor is implicitly derived by a ratio of the carrier indicator numbers (N _CI) of the co-scheduled cells in a code-point indicator or co-scheduled cells indicator table, such as Table 3 for example. To illustrate, using Table 3,

Cells

0, 1, and 2 are each indicated four times and Cell 3 is indicated three times in Table 3, providing a ratio of 4: 4: 4: 3 for the co-scheduled cells. Normalizing the ratio to 1 may, in turn, provide scaling factors of {0.25, 0.25, 0.25, 0.25} for

Cells

0, 1, 2, and 3, respectively, which the user device 102 may then use to scale down the counts. For particular of these embodiments, the user device 102 may perform scaling in event no RRC configuration is used.

In other embodiments, the user device 102 may perform scaling for each co-scheduled cell that is not configured with a SC-DCI. Referring to the multi-cell scheduling in Fig. 5 to illustrate,

Cells

1, 2, and 3 are each not configured with a SC-DCI, as previously described. Accordingly, the user device 102 may determine to perform scaling for

Cells

1, 2, and 3, but not for Cell 4. For at least some of these embodiments, the user device 102 may use scaling factors to perform the scaling. In particular of these embodiments, the scaling factors may be determined based on the ratios of carrier indicator numbers (N _CI) , as previously described. One benefit of these embodiments is that where both MC-DCI and SC-DCI are both supported for a scheduled cell for a user device, scaling the counting for those co-scheduled cells not configured with a SC-DCI may allow the user device to not exceed a current DCI size budget or a blind decode/CCE budget while still supporting MC-DCI transmission.

In addition or alternatively, for at least some embodiments of the method 300 and/or the method 400, the multi-cell scheduling using MC-DCIs may be combined with or without PCell-scheduled-by-SCell, where PCell refers to a primary cell, and SCell refers to a secondary cell. In general, as used herein, PCell-scheduled-by-SCell (also called “sSCell-schedule-PCell” or “s-p scheduling” ) is a type of scheduling where an SCell schedules the PCell. Also, a SCell that schedules a PCell is called a scheduling SCell or sSCell. Another type of scheduling is PCell self-scheduling (also called “p-p scheduling” ) , where the PCell schedules itself. There may be several scenarios involving a combination of multi-cell scheduling and PCell self-scheduling and/or PCell-scheduled-by-SCell, at least some of which are shown in Figs. 7-10.

Fig. 7 shows a diagram of four co-scheduled cells that does not include PCell-scheduled-by-SCell (i.e., s-p scheduling is not configured for the cells shown in Fig. 7) . Rather, a primary cell (PCell 1) schedules itself and Cell 2 with a first MC-DCI, and a SCell 3 schedules itself and Cell 4 with a second MC-DCI.

In the diagram in Fig. 8, PCell 1 performs p-p scheduling with a SC-DCI, and sSCell 3 performs s-p scheduling for PCell 1 with a MC-DCI. The sSCell 3 also schedules itself, Cell 2 and Cell 4 with the MC-DCI.

The diagram in Fig. 9 illustrates an example where the PCell supports scheduling with a MC-DCI and is scheduled by a sSCell. PCell 1 performs p-p scheduling with a first MC-DCI, and also schedules Cell 2 with the first MC-DCI. Also, sSCell 3 performs s-p scheduling for PCell 1 with a second MC-DCI, and also schedules itself and Cell 4 with the second MC-DCI.

In the diagram in Fig. 10, PCell 1 performs p-p scheduling and also schedules Cell 2 and sSCell 3 with a first MC-DCI, and sSCell 3 performs s-p scheduling for PCell with a second MC-DCI and also schedules itself and Cell 4 with the second MC-DCI.

Additionally, for at least some embodiments, a size of a DCI format used for p-p scheduling and a size of a DCI format used for s-p scheduling are aligned. For example, the network device 104 may perform size alignment by zero padding to ensure the DCIs of the two formats have the same size.

In addition or alternatively, in event that MC-DCI and s-p scheduling are both configured, such as in Figs. 8-10, size alignment may be performed and/or determined according to any of the following various schemes. In a first scheme, a first MC-DCI (which may be or include the MC-DCI detected/transmitted at

blocks

302, 402, respectively) , may be transmitted on a SCell for s-p scheduling. For example, a plurality of co-scheduled cells may include a PCell that is configured to be scheduled by the SCell. For a DCI format used for PCell self-scheduling and a DCI format used for PCell-scheduled-by-SCell: a size of the DCI format used for PCell self-scheduling and a size of the DCI format used for PCell-scheduled-by-SCell are self-aligned. In addition, the DCI format used for PCell self-scheduling and the DCI format used for PCell-scheduled-by-SCell are the same DCI format, and a first number of the plurality of co-scheduled cells configured with the first MC-DCI on the SCell transmitted on the SCell is the same as a second number of the plurality of co-scheduled cells configured with a second MC-DCI transmitted on the PCell, or the first MC-DCI is used for PCell self-scheduling and PCell-scheduled-by-SCell. Additionally, for at least some embodiments using the first scheme, the sizes of the two DCI formats may be aligned only when, or on condition that, the number of co-scheduled cells configured with the first MC-DCI transmitted on the PCell and the number of co-scheduled cells configured with the second MC-DCI transmitted on the SCell are the same, or the first MC-DCI is used for both p-p scheduling and s-p scheduling.

In a second scheme, a first MC-DCI (which may be or include the MC-DCI detected/transmitted at

blocks

302, 402, respectively) , may be transmitted on a SCell for s-p scheduling, and a plurality of co-scheduled cells may include a PCell that is configured to be scheduled by the SCell, similar to the first scheme. The user device 102 may not count the size of the first MC-DCI used for s-p scheduling for the PCell, and/or may count the size of the first MC-DCI for one or more of the plurality of co-scheduled cells except the PCell. In particular of these embodiments for the second scheme, the one or more co-scheduled cells for which counting is performed may include a SCell configured to schedule the PCell, a SCell with a lowest cell index among the one or more of the plurality of co-scheduled cells, a SCell configured without a SC-DCI, a SCell configured only as a scheduled cell (e.g., it is not a scheduling cell) , or a SCell configured by only one scheduling cell.

A third scheme may be similar to the scheme, and further that a first number of the plurality of co-scheduled cells configured with the first MC-DCI transmitted on the SCell is not the same as a second number of the plurality of co-scheduled cells configured with a second MC-DCI transmitted on the PCell. In particular of these embodiments including the third scheme, the counting and determination not to count may depend on, or be on condition that, the number of co-scheduled cells configured with the first MC-DCI and the number of co-scheduled cells configured with the second MC-DCI are different.

For example, as shown in figure 5, that at most one scheduling cell for MC-DCI for a scheduled cell. And SC-DCI is used for PCell self-scheduling, the co-scheduled cells including PCell are scheduled by MC-DCI that sSCell-schedule-PCell is also supported.

With particular reference to Fig. 8, for some embodiments, the SC-DCI used for p-p scheduling may have a first DCI format (e.g., DCI format 0_1/0_1) , and the MC-DCI used for s-p scheduling may have a second, different DCI format (e.g., DCI format 0_3/1_3) . In some embodiments, the first and second DCI formats are not aligned with each other. In addition or alternatively, the user device 102 may count a size of the MC-DCI for at least the PCell. In other embodiments, the user device 102 may not count a size of the MC-DCI used for s-p scheduling for the PCell, or may count the size of the MC-DCI for at least one of the SCells, e.g. the sSCell, or a cell with a lowest cell index, or a cell not configured with SC-DCI.

In addition or alternatively, still with reference to Fig. 8, if the DCI format of the MC-DCI used for s-p scheduling and the DCI format of the SC-DCI used for p-p scheduling are both legacy formats (e.g, DCI format 0_1/1_1) , whether the sizes of the DCI formats used for the SC-DCI for p-p scheduling and for the MC-DCI for s-p scheduling are aligned may depend on one of the following schemes. In a first scheme, the SC-DCI for p-p scheduling and the MC-DCI for s-p scheduling are aligned, which in turn may lead to the size of the SC-DCI being extended because the same DCI format used for MC-DCI may initially have a larger size before size alignment. In a second scheme, the same DCI format for p-p scheduling and for s-p scheduling are not, or do not have to be, aligned. . In a third scheme, the user device 102 determines not to count a size of the MC-DCI used for s-p scheduling for the PCell, or the user device counts the size of the MC-DCI for at least one of the SCells, e.g. the sSCell, a SCell having a lowest cell index, or cell only configured as scheduled cell.

In the example in Fig. 9, p-p scheduling supports MC-DCI, and the PCell can schedule other SCells even if s-p scheduling is supported. In addition, co-scheduled cells including the PCell scheduled by a MC-DCI and s-p scheduling with a MC-DCI is also supported.

For the configuration in Fig. 9, whether a first DCI format of the first MC-DCI for p-p scheduling and a second DCI format of the second MC-DCI for s-p scheduling are aligned may depend on, or be in accordance with, one the following schemes. In a first scheme, the first and second DCI formats are always aligned, or are aligned only when the number of co-scheduled cells configured with the first MC-DCI transmitted on the PCell and the number of co-scheduled cells configured with the MC-DCI transmitted on the sSCell are same. In a second scheme, the user device 102 determines not to count the size of second MC-DCI used for s-p scheduling for the PCell, or the size of the second MC-DCI used for s-p scheduling is counted for one or more of the SCells, such as the sSCell, a SCell having a lowest cell index, or a cell not configured with SC-DCI. A third scheme may be similar to the second scheme, with the addition that the number of co-scheduled cells configured for first MC-DCI transmitted on the PCell and the number of co-scheduled cells configured for the second MC-DCI transmitted on the sSCell are different.

In addition or alternatively, still with reference to Fig. 9, in event that the MC-DCIs used for p-p scheduling and s-p scheduling both have a legacy format (e.g. DCI format 0_1/1_1) , both the p-p scheduling and the s-p scheduling may use a MC-DCI. Further, whether the DCI format of the first MC-DCI for p-p scheduling and the DCI format of the second MC-DCI for s-p scheduling are aligned may further depend on or be in accordance with one of following schemes. In a first scheme, the sizes of the two DCI formats are always aligned, or are aligned only when the number of co-scheduled cells configured with the first MC-DCI transmitted on the PCell and the number of co-scheduled cells configured with the second MC-DCI transmitted on the sSCell are same. In a second scheme, the user device does not count a size of the second MC-DCI used for s-p scheduling for the PCell, or counts the size of the MC-DCI one or more SCells, e.g. the sSCell, a SCell having a lowest cell index, or a cell only configured as scheduled cell. A third scheme is similar to the second scheme, with the addition that the number of co-scheduled cells configured with the first MC-DCI transmitted on the PCell and the number of co-scheduled cells configured for the second MC-DCI transmitted on the sSCell are different.

In the example in Fig. 10, the sSCell can be scheduled by the PCell with a first MC-DCI, the PCell can schedule other SCells, and s-p scheduling is supported. The MC-DCI used for s-p scheduling is also used to schedule other co-scheduled cells that include the PCell.

For at least some embodiments of Fig. 10, the MC-DCIs used for s-p scheduling and p-p scheduling may have a legacy DCI format (e.g., DCI format 0_1/1_1) , or may have a format different from the legacy format (e.g. DCI format 0_3/1_3) . Whether the sizes of the DCI formats of the first MC-DCI used for p-p scheduling and the second MC-DCI for s-p scheduling are aligned may depend on or be in accordance with one of the following schemes. In a first scheme, the sizes are always aligned, or are aligned only when the number of co-scheduled cells configured with the MC-DCI transmitted on the PCell and the number of co-scheduled cells configured with the second MC- DCI transmitted on the sSCell are same. In a second scheme, the user device 102 does not count the size of the second MC-DCI used for s-p scheduling for the PCell, or counts the size of the second MC-DCI in one or more of the SCells, e.g. the sSCell, a SCell with the lowest cell index, or the cell configured with only one scheduling cell. A third scheme may be similar to the second scheme, with the addition that the number of co-scheduled cells configured with the first MC-DCI transmitted on the PCell and the number of co-scheduled cells configured with the second MC-DCI transmitted on the sSCell are different.

One benefit of the above-described alignment and counting schemes may be that both MC-DCI and s-p scheduling can be both supported for a user device, and DCI formats used for p-p scheduling and s-p scheduling are aligned in accordance with a condition, or the size of the MC-DCI used for s-p scheduling is not counted for the PCell. This, in turn, may allow the user device to not exceed a current DCI size budget while also supporting MC-DCI transmission and s-p scheduling.

In addition or alternatively, in various embodiments, a MC-DCI and a SC-DCI may be supported for a co-scheduled cell simultaneously. For at least some of these embodiments, for a Type-2 HARQ-ACK codebook, two sub-codebooks may be generated, with a first sub-codebook comprising HARQ-ACK information bits for PDSCH (s) scheduled by DCI (s) with each scheduling a single cell, and a second sub-codebook comprising HARQ-ACK information bits for PDSCH (s) scheduled by DCI (s) , with each scheduling more than one cell. For at least some of these embodiments, the user device 102 may perform separate downlink assignment index (DAI) counting for each of the DCI (s) scheduling a single cell and for each of the DCI (s) scheduling more than one cell. For such embodiments, type-2 HARQ-ACK codebook may be generated by concatenating the first sub-codebook and the second sub-codebook. In addition or alternatively, a number of HARQ-ACK information bits for each DCI format 1_X that schedules more than one cell is determined based on the maximum number of cells co-scheduled by a DCI format 1_X in the PUCCH-group for the user device 102. In addition or alternatively, HARQ-ACK information bits for co-scheduled PDSCHs by a DCI format 1_X is ordered based on serving cell indices associated with co-scheduled PDSCHs.

In addition or alternatively, in various embodiments, if a code block group (CBG) -based PDSCH transmission or a second transport block (TB) in one PDSCH or multiple transmission time interval (multi-TTI) PDSCH transmission can be supported by SC-DCI, but not support by MC-DCI for scheduling multiple cells. For such embodiments, single cell scheduling by the MC-DCI may be determined according to one of the following schemes. In a first scheme, the MC-DCI may be used to schedule a single cell as a fallback scheduling of the SC-DCI and to reinterpret one or more fields to indicate fields for CBG/TB2/multi-TTI. For example, using the reserved or unused separate sub-fields (e.g. frequency domain resource allocation (FDRA) or modulation and coding scheme (MCS) ) to indicate the CBG transmission information (CBGTI) or CBG flushing out information (CBGFI) or MCS/redundancy version (RV) /new data indicator (NDI) for the second TB. In a second scheme, CBG/TB2/multi-TTI is not supported by the MC-DCI scheduling more than one cell, and multi-TTI is supported by the MC-DCI scheduling only one cell (e.g. using the same time domain resource allocation (TDRA) table with some entries, or using another TDRA table) . One advantage is that where both MC-DCI and SC-DCI can be supported for a user device, and where a DCI format used for p-p scheduling and s-p scheduling are aligned, or where the MC-DCI used for s-p scheduling is not counted in the PCell, the user device may not to exceed a current DCI size budget while also supporting MC-DCI transmission and s-p scheduling.

The description and accompanying drawings above provide specific example embodiments and implementations. The described subject matter may, however, be embodied in a variety of different forms and, therefore, covered or claimed subject matter is intended to be construed as not being limited to any example embodiments set forth herein. A reasonably broad scope for claimed or covered subject matter is intended. Among other things, for example, subject matter may be embodied as methods, devices, components, systems, or non-transitory computer-readable media for storing computer codes. Accordingly, embodiments may, for example, take the form of hardware, software, firmware, storage media or any combination thereof. For example, the method embodiments described above may be implemented by components, devices, or systems including memory and processors by executing computer codes stored in the memory.

Throughout the specification and claims, terms may have nuanced meanings suggested or implied in context beyond an explicitly stated meaning. Likewise, the phrase “in one embodiment/implementation” as used herein does not necessarily refer to the same embodiment and the phrase “in another embodiment/implementation” as used herein does not necessarily refer to a different embodiment. It is intended, for example, that claimed subject matter includes combinations of example embodiments in whole or in part.

In general, terminology may be understood at least in part from usage in context. For example, terms, such as “and” , “or” , or “and/or, ” as used herein may include a variety of meanings that may depend at least in part on the context in which such terms are used. Typically, “or” if used to associate a list, such as A, B or C, is intended to mean A, B, and C, here used in the inclusive sense, as well as A, B or C, here used in the exclusive sense. In addition, the term “one or more” as used herein, depending at least in part upon context, may be used to describe any feature, structure, or characteristic in a singular sense or may be used to describe combinations of features, structures or characteristics in a plural sense. Similarly, terms, such as “a, ” “an, ” or “the, ” may be understood to convey a singular usage or to convey a plural usage, depending at least in part upon context. In addition, the term “based on” may be understood as not necessarily intended to convey an exclusive set of factors and may, instead, allow for existence of additional factors not necessarily expressly described, again, depending at least in part on context.

Reference throughout this specification to features, advantages, or similar language does not imply that all of the features and advantages that may be realized with the present solution should be or are included in any single implementation thereof. Rather, language referring to the features and advantages is understood to mean that a specific feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present solution. Thus, discussions of the features and advantages, and similar language, throughout the specification may, but do not necessarily, refer to the same embodiment.

Furthermore, the described features, advantages and characteristics of the present solution may be combined in any suitable manner in one or more embodiments. One of ordinary skill in the relevant art will recognize, in light of the description herein, that the present solution can be practiced without one or more of the specific features or advantages of a particular embodiment. In other instances, additional features and advantages may be recognized in certain embodiments that may not be present in all embodiments of the present solution.

The subject matter of the disclosure may also relate to or include, among others, the following aspects:

A first aspect includes a method for a multi-cell downlink control information (MC-DCI) transmission that includes: detecting, by a user device, a MC-DCI for scheduling a plurality of co-scheduled cells in one or more search spaces; and communicating, by the user device, at least one traffic channel on at least one actual co-scheduled cell according to a co-scheduled cells indicator in the MC-DCI.

A second aspect includes a method for a multi-cell downlink control information (MC-DCI) transmission that includes: transmitting, by a network device, a MC-DCI for scheduling a plurality of co-scheduled cells in one or more search spaces; and communicating, by the network device, at least one traffic channel on at least one actual co-scheduled cell according to a co-scheduled cells indicator in the MC-DCI.

A third aspect includes any of the first or second aspects, and further includes wherein the one or more search spaces comprises one of: a search space of one of the actual co-scheduled cells according to the co-scheduled cells indicator; a search space of any one of the plurality of co-scheduled cells; or a search space of a scheduling cell when a carrier indicator number (N _CI) is 0 or greater than 7.

A fourth aspect includes the third aspect, and further includes wherein the one or more search spaces comprises the search space of the any one of the plurality of co-scheduled, and wherein search space sharing is configured or supported for the plurality of co-scheduled cells scheduled by the MC-DCI.

A fifth aspect includes any of the first through fourth aspects, and further includes determining, by the user device, at least one of a following count for a co-scheduled cell of the plurality of co-scheduled cells: a number of blind decodes (BD) of one or more monitored physical downlink control channel (PDCCH) carrying a respective MC-DCI; a number of non-overlapped control channel elements (CCEs) of one or more monitored PDCCH carrying a respective MC-DCI; or a number of MC-DCI sizes.

A sixth aspect includes the fifth aspect, and further includes wherein the co-scheduled cell is not configured with a single-cell downlink control information (SC-DCI) or the co-scheduled cell is configured by radio resource control (RRC) signaling.

A seventh aspect includes any of the fifth or sixth aspects, and further includes wherein at least two co-scheduled cells of the plurality of co-scheduled cells are not configured with a single-cell downlink control information (SC-DCI) , and the co-scheduled cell is determined according to one of: the co-scheduled cell has a lowest cell index of the at least two co-scheduled cells; the co-scheduled cell is not configured with all single cell scheduling DCI formats; the co-scheduled cell is configured with both the SC-DCI and the MC-DCI transmitted on a same scheduling cell; or the co-scheduled cell is configured by radio resource control (RRC) signaling.

An eighth aspect includes any of the sixth or seventh aspects, and further includes wherein the co-scheduled cell is configured by RRC signaling, and determining, by the user device, a different co-scheduled cell for the count in response to the co-scheduled cell being deactivated or dormant, the different co-scheduled cell determined according to one of: the different co-scheduled cell has a lowest cell index among activated cells of the plurality of co-scheduled cells, or the different co-scheduled cell is not configured with all single cell scheduling DCI formats.

A ninth aspect includes any of the first or second aspects, and further includes wherein the MC-DCI comprises a first MC-DCI transmitted on a secondary cell (SCell) , wherein the plurality of co-scheduled cells comprises a primary cell (PCell) , and wherein the PCell is configured to be scheduled by the SCell, and wherein for a DCI format used for PCell self-scheduling and for a DCI format used for PCell-scheduled-by-SCell: a size of the DCI format used for PCell self-scheduling and a size of the DCI format used for PCell-scheduled-by-SCell are aligned, and the DCI format used for PCell self-scheduling and the DCI format used for PCell-scheduled-by-SCell are the same DCI format, and a first number of the plurality of co-scheduled cells configured with the first MC-DCI transmitted on the SCell is the same as a second number of the plurality of co-scheduled cells configured with a second MC-DCI transmitted on the PCell, or the first MC-DCI is used for PCell self-scheduling and PCell-scheduled-by-SCell.

An tenth aspect includes any of the first or second aspects, and further includes wherein the MC-DCI comprises a first MC-DCI transmitted on a secondary cell (SCell) , wherein the plurality of co-scheduled cells comprises a primary cell (PCell) , wherein the PCell is configured to be scheduled by the SCell, and wherein the method further comprises at least one of: determining, by the user device, not to count a size of the first MC-DCI for the PCell in response to the MC-DCI used for PCell-scheduled-by-SCell; or counting, by the user device, the size of the first MC-DCI for one or more of the plurality of co-scheduled cells except the PCell.

An eleventh aspect includes the tenth aspect, and further includes wherein the one or more of the plurality of co-scheduled cells comprises: a SCell configured to schedule the PCell; a SCell with a lowest cell index among the one or more of the plurality of co-scheduled cells; a SCell configured without a single-cell downlink control information (SC-DCI) ; a SCell configured only as a scheduled cell; or a SCell configured by only one scheduling cell.

A twelfth aspect includes any of the tenth or eleventh aspects, and further includes wherein a first number of the plurality of co-scheduled cells configured with the first MC-DCI transmitted on the SCell is not the same as a second number of the plurality of co-scheduled cells configured with a second MC-DCI transmitted on the PCell.

A thirteenth aspect includes any of the first through twelfth aspects, and further includes wherein the co-scheduled cells indicator is one value of a co-scheduled cells indicator table, and wherein one of: the co-scheduled cells indicator table is configured in the scheduling cell; each co-scheduled cell is configured with only those rows of the co-scheduled cells indicator table for which the co-scheduled cell is at least part of a combination of one or more of the plurality of co-scheduled cells indicated by the row; or the co-scheduled cells indicator table is configured in a cell group.

A fourteenth aspect includes a wireless communications apparatus comprising a processor and a memory, wherein the processor is configured to read code from the memory to implement any of the first through thirteenth aspects.

A fifteenth aspect includes a computer program product comprising a computer-readable program medium comprising code stored thereupon, the code, when executed by a processor, causing the processor to implement any of the first through thirteenth aspects.

In addition to the features mentioned in each of the independent aspects enumerated above, some examples may show, alone or in combination, the optional features mentioned in the dependent aspects and/or as disclosed in the description above and shown in the figures.

Claims

A method for a multi-cell downlink control information (MC-DCI) transmission, the method comprising:

detecting, by a user device, a MC-DCI for scheduling a plurality of co-scheduled cells in one or more search spaces; and

communicating, by the user device, at least one traffic channel on at least one actual co-scheduled cell according to a co-scheduled cells indicator in the MC-DCI.
A method for a multi-cell downlink control information (MC-DCI) transmission, the method comprising:

transmitting, by a network device, a MC-DCI for scheduling a plurality of co-scheduled cells in one or more search spaces, and

communicating, by the network device, at least one traffic channel on at least one actual co-scheduled cell according to a co-scheduled cells indicator in the MC-DCI.
The method of claims 1 or 2, wherein the one or more search spaces comprises one of:

a search space of one of the actual co-scheduled cells according to the co-scheduled cells indicator;

a search space of any one of the plurality of co-scheduled cells; or

a search space of a scheduling cell when a carrier indicator number (N _CI) is 0 or greater than 7.
The method of claim 3, wherein the one or more search spaces comprises the search space of the any one of the plurality of co-scheduled, and wherein search space sharing is configured or supported for the plurality of co-scheduled cells scheduled by the MC-DCI.
The method of claims 1 or 2, further comprising: determining, by the user device, at least one of a following count for a co-scheduled cell of the plurality of co-scheduled cells:

a number of blind decodes (BD) of one or more monitored physical downlink control channel (PDCCH) carrying a respective MC-DCI;

a number of non-overlapped control channel elements (CCEs) of one or more monitored PDCCH carrying a respective MC-DCI; or

a number of MC-DCI sizes.
The method of claim 5, wherein the co-scheduled cell is not configured with a single-cell downlink control information (SC-DCI) or the co-scheduled cell is configured by radio resource control (RRC) signaling.
The method of claim 5, wherein at least two co-scheduled cells of the plurality of co-scheduled cells are not configured with a single-cell downlink control information (SC-DCI) , and the co-scheduled cell is determined according to one of:

the co-scheduled cell has a lowest cell index of the at least two co-scheduled cells;

the co-scheduled cell is not configured with all single cell scheduling DCI formats;

the co-scheduled cell is configured with both the SC-DCI and the MC-DCI transmitted on a same scheduling cell; or

the co-scheduled cell is configured by radio resource control (RRC) signaling.
The method of claims 6 or 7, wherein the co-scheduled cell is configured by RRC signaling, the method further comprising:

determining, by the user device, a different co-scheduled cell for the count in response to the co-scheduled cell being deactivated or dormant, the different co-scheduled cell determined according to one of:

the different co-scheduled cell has a lowest cell index among activated cells of the plurality of co-scheduled cells, or

the different co-scheduled cell is not configured with all single cell scheduling DCI formats.
The method of claims 1 or 2, wherein the MC-DCI comprises a first MC-DCI transmitted on a secondary cell (SCell) , wherein the plurality of co-scheduled cells comprises a primary cell (PCell) , and wherein the PCell is configured to be scheduled by the SCell, and wherein for a DCI format used for PCell self-scheduling and for a DCI format used for PCell-scheduled-by-SCell:

a size of the DCI format used for PCell self-scheduling and a size of the DCI format used for PCell-scheduled-by-SCell are aligned, and

the DCI format used for PCell self-scheduling and the DCI format used for PCell-scheduled-by-SCell are the same DCI format, and a first number of the plurality of co-scheduled cells configured with the first MC-DCI transmitted on the SCell is the same as a second number of the plurality of co-scheduled cells configured with a second MC-DCI transmitted on the PCell, or the first MC-DCI is used for PCell self-scheduling and PCell-scheduled-by-SCell.
The method of claims 1 or 2, wherein the MC-DCI comprises a first MC-DCI transmitted on a secondary cell (SCell) , wherein the plurality of co-scheduled cells comprises a primary cell (PCell) , wherein the PCell is configured to be scheduled by the SCell, and wherein the method further comprises at least one of:

determining, by the user device, not to count a size of the first MC-DCI for the PCell in response to the MC-DCI used for PCell-scheduled-by-SCell; or

counting, by the user device, the size of the first MC-DCI for one or more of the plurality of co-scheduled cells except the PCell.
The method of claim 10, wherein the one or more of the plurality of co-scheduled cells comprises:

a SCell configured to schedule the PCell;

a SCell with a lowest cell index among the one or more of the plurality of co-scheduled cells;

a SCell configured without a single-cell downlink control information (SC-DCI) ;

a SCell configured only as a scheduled cell; or

a SCell configured by only one scheduling cell.
The method of claim 10, wherein a first number of the plurality of co-scheduled cells configured with the first MC-DCI transmitted on the SCell is not the same as a second number of the plurality of co-scheduled cells configured with a second MC-DCI transmitted on the PCell.
The method of claims 1 or 2, wherein the co-scheduled cells indicator is one value of a co-scheduled cells indicator table, and wherein one of:

the co-scheduled cells indicator table is configured in the scheduling cell;

each co-scheduled cell is configured with only those rows of the co-scheduled cells indicator table for which the co-scheduled cell is at least part of a combination of one or more of the plurality of co-scheduled cells indicated by the row; or

the co-scheduled cells indicator table is configured in a cell group.
A wireless communications apparatus comprising a processor and a memory, wherein the processor is configured to read code from the memory to implement a method of any of claims 1 to 13.
A computer program product comprising a computer-readable program medium comprising code stored thereupon, the code, when executed by a processor, causing the processor to implement a method of any of claims 1 to 13.