EP4338510A1

EP4338510A1 - Apparatuses and methods for transmitting multiple control information using a single transmitter chain

Info

Publication number: EP4338510A1
Application number: EP21940162.7A
Authority: EP
Inventors: Yongxia Lyu; Jianglei Ma; Liqing Zhang
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2021-05-20
Filing date: 2021-05-20
Publication date: 2024-03-20
Also published as: WO2022241706A1; CN117322085A

Abstract

In some wireless communication scenarios, it may be intended that a user equipment (UE) is to transmit control information on multiple carriers, with each carrier carrying respective control information associated with a respective different TRP and/or cell and/or cell group. The UE can implement multiple transmitter chains, but the provision of multiple transmitter chains is expensive. Embodiments are disclosed in which a UE instead implements a single transmitter chain for transmitting control information associated with two different TRPs, cells, and/or cell groups. The control information is time-division multiplexed, with various rules implemented in different scenarios, such as when the control information overlaps in time.

Description

Apparatuses and Methods for Transmitting Multiple Control Information Using a Single Transmitter Chain

FIELD

The present application relates to wireless communication, and more specifically to transmission of control information, such as HARQ feedback.

BACKGROUND

In some wireless communication systems, electronic devices, such as user equipments (UEs) , wirelessly communicate with a network via one or more transmit-and-receive points (TRPs) . A TRP may be a terrestrial TRP (T-TRP) or non-terrestrial TRP (NT-TRP) . An example of a T-TRP is a stationary base station or Node B. An example of a NT-TRP is a TRP that can move through space to relocate, e.g. a TRP mounted on a drone, plane, and/or satellite, etc.
A wireless communication from a UE to a TRP is referred to as an uplink communication. A wireless communication from a TRP to a UE is referred to as a downlink communication. Resources are required to perform uplink and downlink communications. For example, a UE may wirelessly transmit information to a TRP in an uplink communication over a particular frequency (or range of frequencies) for a particular duration of time. The frequency and time duration are examples of resources, typically referred to as time-frequency resources. In some scenarios, a UE may transmit uplink control information (UCI) in an uplink communication. One example of UCI is hybrid automatic repeat request (HARQ) feedback, although UCI is not limited to HARQ feedback and may include additional or different information, e.g. a channel measurement report.
A wireless communication may be transmitted on a carrier frequency. A carrier frequency may also be referred to as a carrier. A carrier may alternatively be called a component carrier (CC) . A carrier may be characterized by its bandwidth and a reference frequency, e.g. the center or lowest or highest frequency of the carrier. Sometimes the reference frequency of the carrier is called the carrier frequency.
A UE uses radio frequency (RF) components to implement wireless communication. Some RF components may instead be called analog components. One or more RF components used for reception of a wireless communication will be referred to as a receiver chain. One or more RF components used for transmission of a wireless communication will be referred to as a transmitter chain. A transmitter chain typically includes at least an antenna port or transmit antenna. However, a transmitter chain may also include other RF components, e.g. a power amplifier, a frequency up-convertor, etc.
Different mechanisms are implemented to try to increase the bandwidth for wireless communication, e.g. to allow for more throughput. As one example, carrier aggregation (CA) may be implemented in which multiple carriers are assigned to the same UE. Time-frequency resources may be allocated for communicating on the carriers. A carrier used to transmit information in the downlink will be referred to as a downlink carrier, and a carrier used to transmit information in the uplink will be referred to as an uplink carrier. In some cases, dual connectivity (DC) may be implemented in which the UE simultaneously transmits and receives on multiple carriers with two serving nodes and/or on two cell groups, possibly in different radio access technologies (RATs) .
The use of multiple carriers, such as in CA and/or DC, may result in a need for a UE to implement multiple receiver chains and/or transmitter chains. The provision of multiple receiver and transmitter chains is expensive. In particular, multiple transmitter chains are undesirable, e.g. possibly because of the need to implement and accommodate multiple power amplifiers.
SUMMARY
In some wireless communication scenarios, it may be intended that a UE is to transmit UCI on multiple uplink carriers, with each uplink carrier carrying respective UCI associated with a respective different cell, TRP (e.g. Node B) , and/or cell group. A cell may refer to a carrier. One example scenario is in the context of multiple connectivity, such as DC. For example, the UE might be simultaneously communicating with two TRPs using two different RATs, e.g. the UE might simultaneously communicate with a first TRP using long-term evolution (LTE) and a second TRP using new radio (NR) . UCI related to the LTE wireless communication may be transmitted to the first TRP over a first uplink carrier at a first carrier frequency in LTE, and different UCI related to the NR wireless communication may be transmitted to the second TRP over a second uplink carrier at a second carrier frequency in NR. Another example scenario is when the UE is simultaneously communicating with a same TRP (or different TRPs) on two different cell groups, which might or might not implement different RATs. A cell group may be a group of carriers. A first uplink carrier at a first carrier frequency may be used to send UCI in relation to the first cell group, and a second uplink carrier at a second carrier frequency may be used to send UCI in relation to the second cell group. Another example scenario is when there are multiple physical uplink control channel (PUCCH) cell groups, each having a respective uplink carrier for transmitting UCI for that PUCCH cell group. A first uplink carrier at a first carrier frequency may be used to send UCI in relation to the first PUCCH cell group, and a second uplink carrier at a second carrier frequency may be used to send UCI in relation to the second PUCCH cell group. Another example scenario is the use of multiple cell groups and/or uplink carriers for UCI in the implementation of future 6G systems, such as when implementing MIMO technologies in high frequency bands.
When the UE is to transmit different UCI on multiple uplink carriers in example scenarios such as those outlined above, the UE can implement multiple transmitter chains. Each transmitter chain corresponds to a respective different uplink carrier for carrying the respective UCI. However, the provision of multiple transmitter chains may be expensive, e.g. in terms of power consumption and/or occupying more physical space on the UE (e.g. for heat dissipation) . Therefore, some UEs might only have a single transmitter chain. When a UE does not have enough transmitter chains, e.g. the UE only has a single transmitter chain, the default approach of simply not implementing wireless communication schemes involving the transmission of multiple different UCI on different carriers, may result in less throughput and/or less functionality, which is undesirable.
Moreover, there may be a non-ideal backhaul connection between multiple TRPs and/or cell groups, e.g. a delay of 20ms for the multiple TRPs and/or cell groups to exchange information in the backhaul. For this reason, it might not be feasible to transmit UCI intended for one TRP/cell group to only the other TRP/cell group, with the network forwarding the UCI in the backhaul. The delay in the backhaul may be unacceptable to accommodate the network forwarding UCI received at one TRP /in one cell group to the other TRP /other cell group. In these situations, the UE needs to wirelessly transmit the UCI for each TRP/cell group to that TRP/cell group, which suggests the solution should be implementing multiple transmitter chains at the UE, one for each TRP/cell group. However, a UE might not have multiple transmitter chains, or it may be undesirable to implement multiple transmitter chains on the UE.
To try to mitigate at least one of the technical problems discussed above, embodiments are disclosed in which a UE implements a single transmitter chain for transmitting control information associated with two different cells, TRPs, and/or cell groups. The control information for the two cells, TRPs, and/or cell groups is time-division multiplexed, with various rules implemented in different scenarios, such as when the control information overlaps in time. Different variations of the single transmitter chain are described herein, such as a single transmitter chain that only transmits on a single uplink carrier frequency, or a single transmitter chain that may switch between multiple uplink carrier frequencies.
The control information transmitted by the UE does not necessarily have to be UCI, as described above. For example, the transmission may be control information sent on a sidelink, such as control information sent from the UE to another UE.
In some embodiments, a method performed by an apparatus (e.g. a UE) may include transmitting some or all of first uplink control information using a transmitter chain, where the first uplink control information is associated with at least one of: a first TRP, a first cell, a first cell group, or a first PUCCH cell group. The method may further include transmitting some or all of second uplink control information using a same transmitter chain as the transmitter chain used to transmit the some or all of the first uplink control information, where the second uplink control information is associated with at least one of: a different second TRP, a different second cell, a different second cell group, or a different second PUCCH cell group. In some embodiments, the first uplink control information that is transmitted is time-division multiplexed with the second uplink control information that is transmitted.
In some embodiments, in response to presence of a time gap of a predetermined duration between an end of the first uplink control information and a start of the second uplink control information, the method may include transmitting all of the first uplink control information and all of the second uplink control information using the transmitter chain. In some embodiments, in response to an overlap in time between a first portion of the first uplink control information and a second portion of the second uplink control information, the method may include transmitting the first portion of the first uplink control information using the transmitter chain and not transmitting the second portion of the second uplink control information.
In some embodiments, a method performed by a device (e.g. network device) may include receiving, from an apparatus (such as a UE) , an indication that the apparatus has a single transmitter chain to support transmission of first uplink control information and second uplink control information. The first uplink control information may be associated with at least one of: a first TRP, a first cell, a first cell group, or a first PUCCH cell group. The second uplink control information may be associated with at least one of: a different second TRP, a different second cell, a different second cell group, or a different second PUCCH cell group. The method may further include, in response to receiving the indication: transmitting a message for the apparatus. The message may configure the apparatus to perform time-division multiplexing of the first uplink control information and the second uplink control information to transmit some or all of the first uplink control information and some or all of the second uplink control information using the single transmitter chain. The method may further include subsequently receiving, from the apparatus, the some or all of the first uplink control information and the some or all of the second uplink control information.
Technical benefits of some embodiments include the ability for a UE to use a single transmitter chain to support a wireless communication scenario in which multiple transmitter chains are typically used, such as DC or CA with multiple PUCCH cell groups.
Corresponding apparatuses are disclosed for performing the methods.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will be described, by way of example only, with reference to the accompanying figures wherein:
FIG. 1 is a simplified schematic illustration of a communication system, according to one example;
FIG. 2 illustrates another example of a communication system;
FIG. 3 illustrates an example of an electronic device (ED) , a terrestrial transmit and receive point (T-TRP) , and a non-terrestrial transmit and receive point (NT-TRP) ;
FIG. 4 illustrates example units or modules in a device;
FIG. 5 illustrates a UE communicating with a TRP, according to one embodiment;
FIG. 6 illustrates a UE communicating with two TRPs, according to one embodiment;
FIGs. 7 and 8 illustrate a UE having two separate transmitter chains, according to various embodiments;
FIGs. 9 to 11 illustrates a UE with only a single transmitter chain, according to various embodiments;
FIG. 12 illustrates an example of a situation in which there is a time gap between the end of one uplink control channel and the start of another uplink control channel;
FIG. 13 illustrates examples of time overlap and different rules that may be implemented by a UE, according to various scenarios;
FIG. 14 illustrates an example in which the time gap between the end of one uplink control channel and the start of another uplink control channel is greater than or equal to a switching time, according to one embodiment;
FIGs. 15 and 16 illustrate scenarios in which a time gap between the end of one uplink control channel and the start of another uplink control channel is less than a switching time; and
FIG. 17 illustrates a method performed by an apparatus and a device, according to one embodiment.

DETAILED DESCRIPTION

For illustrative purposes, specific example embodiments will now be explained in greater detail below in conjunction with the figures.
Example communication systems and devices
Referring to FIG. 1, as an illustrative example without limitation, a simplified schematic illustration of a communication system 100 is provided. The communication system 100 comprises a radio access network 120. The radio access network 120 may be a next generation (e.g. sixth generation (6G) or later) radio access network, or a legacy (e.g. 5G, 4G, 3G or 2G) radio access network. One or more communication electric device (ED) 110a-120j (generically referred to as 110) may be interconnected to one another or connected to one or more network nodes (170a, 170b, generically referred to as 170) in the radio access network 120. A core network 130 may be a part of the communication system and may be dependent or independent of the radio access technology used in the communication system 100. Also, the communication system 100 comprises a public switched telephone network (PSTN) 140, the internet 150, and other networks 160.
FIG. 2 illustrates an example communication system 100. In general, the communication system 100 enables multiple wireless or wired elements to communicate data and other content. The purpose of the communication system 100 may be to provide content, such as voice, data, video, and/or text, via broadcast, multicast and unicast, etc. The communication system 100 may operate by sharing resources, such as carrier spectrum bandwidth, between its constituent elements. The communication system 100 may include a terrestrial communication system and/or a non-terrestrial communication system. The communication system 100 may provide a wide range of communication services and applications (such as earth monitoring, remote sensing, passive sensing and positioning, navigation and tracking, autonomous delivery and mobility, etc. ) . The communication system 100 may provide a high degree of availability and robustness through a joint operation of the terrestrial communication system and the non-terrestrial communication system. For example, integrating a non-terrestrial communication system (or components thereof) into a terrestrial communication system can result in what may be considered a heterogeneous network comprising multiple layers. Compared to conventional communication networks, the heterogeneous network may achieve better overall performance through efficient multi-link joint operation, more flexible functionality sharing, and faster physical layer link switching between terrestrial networks and non-terrestrial networks.
The terrestrial communication system and the non-terrestrial communication system could be considered sub-systems of the communication system. In the example shown, the communication system 100 includes electronic devices (ED) 110a-110d (generically referred to as ED 110) , radio access networks (RANs) 120a-120b, non-terrestrial communication network 120c, a core network 130, a public switched telephone network (PSTN) 140, the internet 150, and other networks 160. The RANs 120a-120b include respective base stations (BSs) 170a-170b, which may be generically referred to as terrestrial transmit and receive points (T-TRPs) 170a-170b. The non-terrestrial communication network 120c includes an access node 120c, which may be generically referred to as a non-terrestrial transmit and receive point (NT-TRP) 172.
Any ED 110 may be alternatively or additionally configured to interface, access, or communicate with any other T-TRP 170a-170b and NT-TRP 172, the internet 150, the core network 130, the PSTN 140, the other networks 160, or any combination of the preceding. In some examples, ED 110a may communicate an uplink and/or downlink transmission over an interface 190a with T-TRP 170a. In some examples, the EDs 110a, 110b and 110d may also communicate directly with one another via one or more sidelink air interfaces 190b. In some examples, ED 110d may communicate an uplink and/or downlink transmission over an interface 190c with NT-TRP 172.
The air interfaces 190a and 190b may use similar communication technology, such as any suitable radio access technology. For example, the communication system 100 may implement one or more channel access methods, such as code division multiple access (CDMA) , time division multiple access (TDMA) , frequency division multiple access (FDMA) , orthogonal FDMA (OFDMA) , or single-carrier FDMA (SC-FDMA) in the air interfaces 190a and 190b. The air interfaces 190a and 190b may utilize other higher dimension signal spaces, which may involve a combination of orthogonal and/or non-orthogonal dimensions.
The air interface 190c can enable communication between the ED 110d and one or multiple NT-TRPs 172 via a wireless link or simply a link. For some examples, the link is a dedicated connection for unicast transmission, a connection for broadcast transmission, or a connection between a group of EDs and one or multiple NT-TRPs for multicast transmission.
The RANs 120a and 120b are in communication with the core network 130 to provide the EDs 110a 110b, and 110c with various services such as voice, data, and other services. The RANs 120a and 120b and/or the core network 130 may be in direct or indirect communication with one or more other RANs (not shown) , which may or may not be directly served by core network 130, and may or may not employ the same radio access technology as RAN 120a, RAN 120b or both. The core network 130 may also serve as a gateway access between (i) the RANs 120a and 120b or EDs 110a 110b, and 110c or both, and (ii) other networks (such as the PSTN 140, the internet 150, and the other networks 160) . In addition, some or all of the EDs 110a 110b, and 110c may include functionality for communicating with different wireless networks over different wireless links using different wireless technologies and/or protocols. Instead of wireless communication (or in addition thereto) , the EDs 110a 110b, and 110c may communicate via wired communication channels to a service provider or switch (not shown) , and to the internet 150. PSTN 140 may include circuit switched telephone networks for providing plain old telephone service (POTS) . Internet 150 may include a network of computers and subnets (intranets) or both, and incorporate protocols, such as Internet Protocol (IP) , Transmission Control Protocol (TCP) , User Datagram Protocol (UDP) . EDs 110a 110b, and 110c may be multimode devices capable of operation according to multiple radio access technologies, and incorporate multiple transceivers necessary to support such.
FIG. 3 illustrates another example of an ED 110, a base station 170 (e.g. 170a, and/or 170b) , which will be referred to as a T-TRP 170, and a NT-TRP 172. The ED 110 is used to connect persons, objects, machines, etc. The ED 110 may be widely used in various scenarios, for example, cellular communications, device-to-device (D2D) , vehicle to everything (V2X) , peer-to-peer (P2P) , machine-to-machine (M2M) , machine-type communications (MTC) , internet of things (IOT) , virtual reality (VR) , augmented reality (AR) , industrial control, self-driving, remote medical, smart grid, smart furniture, smart office, smart wearable, smart transportation, smart city, drones, robots, remote sensing, passive sensing, positioning, navigation and tracking, autonomous delivery and mobility, etc.
Each ED 110 represents any suitable end user device for wireless operation and may include such devices (or may be referred to) as a user equipment/device (UE) , a wireless transmit/receive unit (WTRU) , a mobile station, a fixed or mobile subscriber unit, a cellular telephone, a station (STA) , a machine type communication (MTC) device, a personal digital assistant (PDA) , a smartphone, a laptop, a computer, a tablet, a wireless sensor, a consumer electronics device, a smart book, a vehicle, a car, a truck, a bus, a train, or an IoT device, an industrial device, or apparatus (e.g. communication module, modem, or chip) in the forgoing devices, among other possibilities. Future generation EDs 110 may be referred to using other terms. Each ED 110 connected to T-TRP 170 and/or NT-TRP 172 can be dynamically or semi-statically turned-on (i.e., established, activated, or enabled) , turned-off (i.e., released, deactivated, or disabled) and/or configured in response to one of more of: connection availability and connection necessity.
The ED 110 includes a transmitter 201 and a receiver 203 coupled to one or more antennas 204. Only one antenna 204 is illustrated. One, some, or all of the antennas may alternatively be panels. The transmitter 201 and the receiver 203 may be integrated, e.g. as a transceiver. The transmitter (or transceiver) is configured to modulate data or other content for transmission by the at least one antenna 204 or network interface controller (NIC) . The receiver (or transceiver) is configured to demodulate data or other content received by the at least one antenna 204. Each transceiver includes any suitable structure for generating signals for wireless or wired transmission and/or processing signals received wirelessly or by wire. Each antenna 204 includes any suitable structure for transmitting and/or receiving wireless or wired signals.
The ED 110 includes at least one memory 208. The memory 208 stores instructions and data used, generated, or collected by the ED 110. For example, the memory 208 could store software instructions or modules configured to implement some or all of the functionality and/or embodiments described herein and that are executed by the processing unit (s) 210. Each memory 208 includes any suitable volatile and/or non-volatile storage and retrieval device (s) . Any suitable type of memory may be used, such as random access memory (RAM) , read only memory (ROM) , hard disk, optical disc, subscriber identity module (SIM) card, memory stick, secure digital (SD) memory card, on-processor cache, and the like.
The ED 110 may further include one or more input/output devices (not shown) or interfaces (such as a wired interface to the internet 150 in FIG. 1) . The input/output devices permit interaction with a user or other devices in the network. Each input/output device includes any suitable structure for providing information to or receiving information from a user, such as a speaker, microphone, keypad, keyboard, display, or touch screen, including network interface communications.
The ED 110 further includes a processor 210 for performing operations including those related to preparing a transmission for uplink transmission to the NT-TRP 172 and/or T-TRP 170, those related to processing downlink transmissions received from the NT-TRP 172 and/or T-TRP 170, and those related to processing sidelink transmission to and from another ED 110. Processing operations related to preparing a transmission for uplink transmission may include operations such as encoding, modulating, transmit beamforming, and generating symbols for transmission. Processing operations related to processing downlink transmissions may include operations such as receive beamforming, demodulating and decoding received symbols. Depending upon the embodiment, a downlink transmission may be received by the receiver 203, possibly using receive beamforming, and the processor 210 may extract signaling from the downlink transmission (e.g. by detecting and/or decoding the signaling) . An example of signaling may be a reference signal transmitted by NT-TRP 172 and/or T-TRP 170. In some embodiments, the processor 276 implements the transmit beamforming and/or receive beamforming based on the indication of beam direction, e.g. beam angle information (BAI) , received from T-TRP 170. In some embodiments, the processor 210 may perform operations relating to network access (e.g. initial access) and/or downlink synchronization, such as operations relating to detecting a synchronization sequence, decoding and obtaining the system information, etc. In some embodiments, the processor 210 may perform channel estimation, e.g. using a reference signal received from the NT-TRP 172 and/or T-TRP 170.
Although not illustrated, the processor 210 may form part of the transmitter 201 and/or receiver 203. Although not illustrated, the memory 208 may form part of the processor 210.
The processor 210, and the processing components of the transmitter 201 and receiver 203 may each be implemented by the same or different one or more processors that are configured to execute instructions stored in a memory (e.g. in memory 208) . Alternatively, some or all of the processor 210, and the processing components of the transmitter 201 and receiver 203 may be implemented using dedicated circuitry, such as a programmed field-programmable gate array (FPGA) , a graphical processing unit (GPU) , or an application-specific integrated circuit (ASIC) .
The T-TRP 170 may be known by other names in some implementations, such as a base station, a base transceiver station (BTS) , a radio base station, a network node, a network device, a device on the network side, a transmit/receive node, a Node B, an evolved NodeB (eNodeB or eNB) , a Home eNodeB, a next Generation NodeB (gNB) , a transmission point (TP) , a site controller, an access point (AP) , or a wireless router, a relay station, a remote radio head, a terrestrial node, a terrestrial network device, or a terrestrial base station, base band unit (BBU) , remote radio unit (RRU) , active antenna unit (AAU) , remote radio head (RRH) , central unit (CU) , distribute unit (DU) , positioning node, among other possibilities. The T-TRP 170 may be macro BSs, pico BSs, relay node, donor node, or the like, or combinations thereof. The T-TRP 170 may refer to the forgoing devices or apparatus (e.g. communication module, modem, or chip) in the forgoing devices.
In some embodiments, the parts of the T-TRP 170 may be distributed. For example, some of the modules of the T-TRP 170 may be located remote from the equipment housing the antennas of the T-TRP 170, and may be coupled to the equipment housing the antennas over a communication link (not shown) sometimes known as front haul, such as common public radio interface (CPRI) . Therefore, in some embodiments, the term T-TRP 170 may also refer to modules on the network side that perform processing operations, such as determining the location of the ED 110, resource allocation (scheduling) , message generation, and encoding/decoding, and that are not necessarily part of the equipment housing the antennas of the T-TRP 170. The modules may also be coupled to other T-TRPs. In some embodiments, the T-TRP 170 may actually be a plurality of T-TRPs that are operating together to serve the ED 110, e.g. through coordinated multipoint transmissions.
The T-TRP 170 includes at least one transmitter 252 and at least one receiver 254 coupled to one or more antennas 256. Only one antenna 256 is illustrated. One, some, or all of the antennas may alternatively be panels. The transmitter 252 and the receiver 254 may be integrated as a transceiver. The T-TRP 170 further includes a processor 260 for performing operations including those related to: preparing a transmission for downlink transmission to the ED 110, processing an uplink transmission received from the ED 110, preparing a transmission for backhaul transmission to NT-TRP 172, and processing a transmission received over backhaul from the NT-TRP 172. Processing operations related to preparing a transmission for downlink or backhaul transmission may include operations such as encoding, modulating, precoding (e.g. MIMO precoding) , transmit beamforming, and generating symbols for transmission. Processing operations related to processing received transmissions in the uplink or over backhaul may include operations such as receive beamforming, and demodulating and decoding received symbols. The processor 260 may also perform operations relating to network access (e.g. initial access) and/or downlink synchronization, such as generating the content of synchronization signal blocks (SSBs) , generating the system information, etc. In some embodiments, the processor 260 also generates the indication of beam direction, e.g. BAI, which may be scheduled for transmission by scheduler 253. The processor 260 performs other network-side processing operations which may be described herein, such as determining the location of the ED 110, determining where to deploy NT-TRP 172, etc. In some embodiments, the processor 260 may generate signaling, e.g. to configure one or more parameters of the ED 110 and/or one or more parameters of the NT-TRP 172. Any signaling generated by the processor 260 is sent by the transmitter 252. Note that “signaling” , as used herein, may alternatively be called control signaling. Dynamic signaling may be transmitted in a control channel, e.g. a physical downlink control channel (PDCCH) , and static or semi-static higher layer signaling may be included in a packet transmitted in a data channel, e.g. in a physical downlink shared channel (PDSCH) .
A scheduler 253 may be coupled to the processor 260. The scheduler 253 may be included within or operated separately from the T-TRP 170. The scheduler 253 may schedule uplink, downlink, and/or backhaul transmissions, including issuing scheduling grants and/or configuring scheduling-free ( “configured grant” ) resources. The T-TRP 170 further includes a memory 258 for storing information and data. The memory 258 stores instructions and data used, generated, or collected by the T-TRP 170. For example, the memory 258 could store software instructions or modules configured to implement some or all of the functionality and/or embodiments described herein and that are executed by the processor 260.
Although not illustrated, the processor 260 may form part of the transmitter 252 and/or receiver 254. Also, although not illustrated, the processor 260 may implement the scheduler 253. Although not illustrated, the memory 258 may form part of the processor 260.
The processor 260, the scheduler 253, and the processing components of the transmitter 252 and receiver 254 may each be implemented by the same or different one or more processors that are configured to execute instructions stored in a memory, e.g. in memory 258. Alternatively, some or all of the processor 260, the scheduler 253, and the processing components of the transmitter 252 and receiver 254 may be implemented using dedicated circuitry, such as a FPGA, a GPU, or an ASIC.
Although the NT-TRP 172 is illustrated as a drone, it is only as an example. The NT-TRP 172 may be implemented in any suitable non-terrestrial form. Also, the NT-TRP 172 may be known by other names in some implementations, such as a non-terrestrial node, a non-terrestrial network device, or a non-terrestrial base station. The NT-TRP 172 includes a transmitter 272 and a receiver 274 coupled to one or more antennas 280. Only one antenna 280 is illustrated. One, some, or all of the antennas may alternatively be panels. The transmitter 272 and the receiver 274 may be integrated as a transceiver. The NT-TRP 172 further includes a processor 276 for performing operations including those related to: preparing a transmission for downlink transmission to the ED 110, processing an uplink transmission received from the ED 110, preparing a transmission for backhaul transmission to T-TRP 170, and processing a transmission received over backhaul from the T-TRP 170. Processing operations related to preparing a transmission for downlink or backhaul transmission may include operations such as encoding, modulating, precoding (e.g. MIMO precoding) , transmit beamforming, and generating symbols for transmission. Processing operations related to processing received transmissions in the uplink or over backhaul may include operations such as receive beamforming, and demodulating and decoding received symbols. In some embodiments, the processor 276 implements the transmit beamforming and/or receive beamforming based on beam direction information (e.g. BAI) received from T-TRP 170. In some embodiments, the processor 276 may generate signaling, e.g. to configure one or more parameters of the ED 110. In some embodiments, the NT-TRP 172 implements physical layer processing, but does not implement higher layer functions such as functions at the medium access control (MAC) or radio link control (RLC) layer. As this is only an example, more generally, the NT-TRP 172 may implement higher layer functions in addition to physical layer processing.
The NT-TRP 172 further includes a memory 278 for storing information and data. Although not illustrated, the processor 276 may form part of the transmitter 272 and/or receiver 274. Although not illustrated, the memory 278 may form part of the processor 276.
The processor 276 and the processing components of the transmitter 272 and receiver 274 may each be implemented by the same or different one or more processors that are configured to execute instructions stored in a memory, e.g. in memory 278. Alternatively, some or all of the processor 276 and the processing components of the transmitter 272 and receiver 274 may be implemented using dedicated circuitry, such as a programmed FPGA, a GPU, or an ASIC. In some embodiments, the NT-TRP 172 may actually be a plurality of NT-TRPs that are operating together to serve the ED 110, e.g. through coordinated multipoint transmissions.
Note that “TRP” , as used herein, may refer to a T-TRP or a NT-TRP.
The T-TRP 170, the NT-TRP 172, and/or the ED 110 may include other components, but these have been omitted for the sake of clarity.
One or more steps of the embodiment methods provided herein may be performed by corresponding units or modules, e.g. according to FIG. 4. FIG. 4 illustrates example units or modules in a device, such as in ED 110, in T-TRP 170, or in NT-TRP 172. For example, operations may be controlled by an operating system module. As another example, a signal may be transmitted by a transmitting unit or a transmitting module. A signal may be received by a receiving unit or a receiving module. A signal may be processed by a processing unit or a processing module. Some operations/steps may be performed by an artificial intelligence (AI) or machine learning (ML) module. The respective units or modules may be implemented using hardware, one or more components or devices that execute software, or a combination thereof. For instance, one or more of the units or modules may be an integrated circuit, such as a programmed FPGA, a GPU, or an ASIC. It will be appreciated that where the modules are implemented using software for execution by a processor for example, they may be retrieved by a processor, in whole or part as needed, individually or together for processing, in single or multiple instances, and that the modules themselves may include instructions for further deployment and instantiation.
Additional details regarding the EDs 110, T-TRP 170, and NT-TRP 172 are known to those of skill in the art. As such, these details are omitted here.
Control information is discussed herein. Control information may sometimes instead be referred to as control signaling, or signaling. In some cases, control information may be dynamically indicated, e.g. in the physical layer in a control channel, such as in a physical uplink control channel (PUCCH) , as described in some embodiments herein. An example of control information that is dynamically indicated is information sent in physical layer control signaling, e.g. uplink control information (UCI) sent in a PUCCH. A dynamic indication may be an indication in lower layer, e.g. physical layer /layer 1 signaling, rather than in a higher-layer (e.g. rather than in RRC signaling or in a MAC CE) . A semi-static indication may be an indication in semi-static signaling. Semi-static signaling, as used herein, may refer to signaling that is not dynamic, e.g. higher-layer signaling (such as RRC signaling) , and/or a MAC CE. Dynamic signaling, as used herein, may refer to signaling that is dynamic, e.g. physical layer control signaling sent in the physical layer, such as DCI sent in a physical downlink control channel (PDCCH) or UCI sent in a PUCCH.
FIG. 5 illustrates an ED communicating with a TRP 352 in the communication system 100, according to one embodiment. The ED is illustrated as a UE, and will be referred to as UE 110. However, the ED does not necessarily need to be a UE.
The TRP 352 may be T-TRP 170 or NT-TRP 172. In some embodiments, the parts of the TRP 352 may be distributed. For example, some of the modules of the TRP 352 may be located remote from the equipment housing the antennas of the TRP 352, and may be coupled to the equipment housing the antennas over a communication link (not shown) . Therefore, in some embodiments, the term TRP 352 may also refer to modules on the network side that perform processing operations, such as resource allocation (scheduling) , message generation, encoding/decoding, etc., and that are not necessarily part of the equipment housing the antennas and/or panels of the TRP 352. For example, the modules that are not necessarily part of the equipment housing the antennas/panels of the TRP 352 may include one or more modules that: process (e.g. decode) UCI sent from the UE 110; generate a message for transmission to the UE 110, e.g. a message configuring time-division multiplexing of first and second control information by UE 110; generate the downlink transmissions for initial access (e.g. SSBs) ; generate scheduled downlink transmissions; process uplink transmissions, etc. The modules may also be coupled to other TRPs. In some embodiments, the TRP 352 may actually be a plurality of TRPs that are operating together to serve UE 110, e.g. through coordinated multipoint transmissions.
The TRP 352 includes a transmitter 354 and receiver 356, which may be integrated as a transceiver. The transmitter 354 and receiver 356 are coupled to one or more antennas 358. Only one antenna 358 is illustrated, although there may be more antennas if the TRP 352 is to receive transmissions on different carrier frequencies f ₁ and f ₂. One, some, or all of the antennas may alternatively be panels. The processor 360 of the TRP 352 performs (or controls the TRP 352 to perform) the operations described herein as being performed by the TRP 352, e.g. processing (e.g. decoding) the transmissions of first and second UCI received from the UE 110, generating messages configuring the UE 110 (e.g. configuring the time-division multiplexing of the control information by the UE 110) , etc. Generation of messages for downlink transmission may include arranging the information in a message format, encoding the message, modulating, performing beamforming (as necessary) , etc. Processing uplink transmissions may include performing beamforming (as necessary) , demodulating and decoding the received messages, etc. Although not illustrated, the processor 360 may form part of the transmitter 354 and/or receiver 356. The TRP 352 further includes a memory 362 for storing information (e.g. control information and/or data) .
The processor 360 and processing components of the transmitter 354 and receiver 356 may be implemented by the same or different one or more processors that are configured to execute instructions stored in a memory (e.g. in memory 362) . Alternatively, some or all of the processor 360 and/or processing components of the transmitter 354 and/or receiver 356 may be implemented using dedicated circuitry, such as a programmed FPGA, a GPU, or an ASIC.
If the TRP 352 is T-TRP 170, then the transmitter 354 may be or include transmitter 252, the receiver 356 may be or include receiver 254, the processor 360 may be or include processor 260 and may implement scheduler 253, and the memory 362 may be or include memory 258. If the TRP 352 is NT-TRP 172, then the transmitter 354 may be or include transmitter 272, the receiver 356 may be or include receiver 274, the processor 360 may be or include processor 276, and the memory 362 may be or include memory 278.
UE 110 includes processor 210, memory 208, transmitter 201, and receiver 203, as described earlier. The processor 210 performs (or controls the UE 110 to perform) much of the operations described herein as being performed by the UE 110, such as: performing time-division multiplexing of first and second control information associated with different TRPs, cells, cell groups, or PUCCH cell groups; determining the presence of a time gap or overlap between the first and second control information and implementing the different rules discussed herein, e.g. refraining from transmitting some or all of the first or second control information in the presence of overlap; switching between multiple carrier frequencies on a single transmitter chain, etc.
The processor 210 generates messages for uplink transmission (e.g. messages carrying control information, such as UCI) , and the processor 210 processes received downlink transmissions. Generation of messages for uplink transmission may include arranging the information in a message format, encoding the message, modulating, performing beamforming (as necessary) , etc. Processing received downlink transmissions may include performing beamforming (as necessary) , demodulating and decoding the received messages, etc. Although not illustrated, the processor 210 may form part of the transmitter 201 and/or receiver 203.
FIG. 5 illustrates the UE 110 sending two uplink transmissions, one on a first carrier frequency f ₁, and one on a different second carrier frequency f ₂. For example, the uplink transmission on the first carrier frequency f ₁ may transmit first UCI, and the uplink transmission on the second carrier frequency f ₂ may transmit different second UCI.
In some embodiments, the first UCI and the second UCI may be associated with respective different cells. A cell may refer to a carrier. In some embodiments, the first UCI and the second UCI may be associated with respective different cell groups. A cell group may refer to a group of carriers. In one example, the UE 110 may communicate on both a primary cell group and a secondary cell group. The primary cell group may be used to establish a connection with the network and communicate on both a user (data) plane and a control plane. The primary cell group may include a primary cell, which is a carrier used for initial access. The secondary cell group may be used to communicate on a user (data) plane but possibly not on a control plane. First UCI related to the primary cell group may be transmitted on a first uplink carrier having carrier frequency f ₁, and different second UCI related to the secondary cell group may be transmitted on a second uplink carrier having carrier frequency f ₂. In another example, the two cell groups might not necessarily be a primary cell group and a secondary cell group, e.g. both cell groups might each be a respective different secondary cell group. In any case, in some embodiments a cell group may have multiple downlink carriers, with a single uplink carrier used to transmit any UCI (e.g. HARQ feedback) associated with the downlink carriers of that cell group. For example, a single uplink carrier may transmit HARQ feedback for downlink transmissions received on the downlink carriers associated with that cell group. The single uplink carrier used to transmit the UCI for one cell group may be transmitted on the first uplink carrier at carrier frequency f ₁, and the single uplink carrier used to transmit the UCI for the other cell group may be transmitted on the second uplink carrier at carrier frequency f ₂. In some embodiments, the first UCI and the second UCI may be associated with respective different PUCCH cell groups. A PUCCH cell group is a cell group in which there is a single uplink carrier for sending UCI (e.g. HARQ feedback) associated with any carriers in the PUCCH cell group. For example, the single uplink carrier may transmit HARQ feedback for downlink transmissions received on the downlink carriers in the PUCCH cell group. A first PUCCH cell group may have an uplink carrier having carrier frequency f ₁ for sending first UCI associated with that first PUCCH cell group, and a second PUCCH cell group may have an uplink carrier having carrier frequency f ₂ for sending second UCI associated with that second PUCCH cell group.
In FIG. 5, the two uplink transmissions are shown as being received at the same TRP 352. Although not shown, there may be a non-ideal backhaul connection such that even though the UCI on carrier frequency f ₁ is sent to the same TRP 352 as the UCI on carrier frequency f ₂, there is a relatively long delay associated with forwarding UCI sent on one carrier on one cell group to the other cell group. Although not shown, each cell or cell group at the TRP 352 may have its own respective receiver chain and associated baseband processing.
FIG. 6 illustrates an alternative to FIG. 5 in which there are two TRPs: TRP 352 and another TRP 372. The components of TRP 372 are omitted for clarity, but TRP 372 may be implemented in the same manner as TRP 352, e.g. have a processor, transmitter, receiver, and memory. In FIG. 6, the UE 110 sends two uplink transmissions, one on a first carrier frequency f ₁, and another on a different second carrier frequency f ₂. The uplink transmission on the first carrier frequency f ₁ transmits UCI destined for TRP 352, and the uplink transmission on the second carrier frequency f ₂ transmits UCI destined for TRP 372. A backhaul connection 388 may be established between the two TRPs 352 and 372. The backhaul connection 388 may be non-ideal such that there is a relatively long delay associated with forwarding UCI sent to one TRP to the other TRP. In one example, the communication with the TRP 352 may be on a first cell group (e.g. a primary cell group) , and the communication with the TRP 372 may be on a second cell group (e.g. a secondary cell group) . A cell group may be a PUCCH cell group.
In the examples herein, the first carrier frequency f ₁ and the second carrier frequency f ₂ may be relatively close to each other, e.g. different carriers in a same frequency band, or may be farther apart, e.g. first carrier frequency f ₁ may be in the sub-6GHz band and second carrier frequency f ₂ may be in the mmWave band or vice versa.
One or more RF components used for transmission of a wireless communication will be referred to as a “transmitter chain” . A transmitter chain typically includes at least an antenna port or transmit antenna. Therefore, a transmitter chain may alternatively or sometimes interchangeably be called an “antenna port” or a “transmit antenna” . However, a transmitter chain may also include other RF components, e.g. a power amplifier, a frequency up-convertor, etc. In one example, a transmitter chain refers to the series of RF components for sending a transmission including at least a digital-to-analog convertor (DAC) , a frequency up-convertor (to a carrier frequency) , a power amplifier, and one or more antennas (or antenna ports or panels) . In another example, the transmitter chain just refers to the antenna port or transmit antenna.
To send respective transmissions of different control information on different uplink carriers, the UE 110 may implement multiple transmitter chains. FIG. 7 illustrates UE 110 having two separate transmitter chains 404 and 424, according to one embodiment. The transmitter 201 includes a baseband processor 402 for preparing the respective transmissions on the two transmitter chains 404 and 424. In some embodiments, the baseband processor 402 is implemented by processor 210. In some embodiments, the baseband processor 402 may be implemented using one or more processors that are configured to execute instructions stored in a memory, whereas in other embodiments some or all of the baseband processor 402 may be implemented using dedicated circuitry, such as a programmed FPGA, a GPU, or an ASIC. Depending upon the implementation, the baseband processor 402 may implement operations such as modulation, encoding, scrambling, etc. The baseband processor 402 generates first UCI to be transmitted on carrier frequency f ₁ by the first transmitter chain 404, and second UCI to be transmitted on carrier frequency f ₂ by the second transmitter chain 424. Although a single baseband processor 402 is illustrated, there may instead be multiple baseband processors, e.g. one to generate the first UCI and another to generate the second UCI.
The transmitter chain 404 includes a digital-to-analog convertor (DAC) 408, a frequency up-convertor 410, a power amplifier 412, and one or more antennas 414 (which may instead be one or more panels) . The frequency up-convertor 410 up-converts the transmission to carrier frequency f ₁, e.g. using an RF oscillator. The transmitter chain 424 includes a DAC 428, a frequency up-convertor 430, a power amplifier 432, and one or more antennas 434 (which may instead be one or more panels) . The frequency up-convertor 430 up-converts the transmission to carrier frequency f ₂, e.g. using an RF oscillator. The transmitter chains 404 and 424 may each include additional components, which have been omitted for the sake of clarity. Also, in some embodiments the transmitter chains 404 and 424 may include different components from those illustrated, or the illustrated components may be present in a different order.
In operation, the baseband processor 402 outputs first UCI associated with a first cell, TRP, and/or cell group, for transmission on a first uplink carrier at carrier frequency f ₁. The first UCI is sent to transmitter chain 404 for transmission. Transmitter chain 404 performs digital-to-analog conversion using DAC 408, performs frequency up-conversion to carrier frequency f ₁ using frequency up-convertor 410, performs power amplification using power amplifier 412, and the first UCI is transmitted on the carrier frequency f ₁. The first UCI is illustrated as being transmitted in a first PUCCH, labelled PUCCH 1. PUCCH 1 has a particular bandwidth (BW 1) , which is illustrated as being centered around carrier frequency f ₁, although this is only an example. The transmission of the first UCI occurs in PUCCH 1 over a particular time duration t _d1, which may be scheduled. The time duration begins at a start time t _s1 and ends at an end time t _e1.
The baseband processor 402 also outputs second UCI associated with a second cell, TRP, and/or cell group, for transmission on a second uplink carrier at carrier frequency f ₂. The second UCI is sent to transmitter chain 424 for transmission. Transmitter chain 424 performs digital-to-analog conversion using DAC 428, performs frequency up-conversion to carrier frequency f ₂ using frequency up-convertor 430, performs power amplification using power amplifier 432, and the second UCI is transmitted on the carrier frequency f ₂. The second UCI is illustrated as being transmitted in a second PUCCH, labelled PUCCH 2. PUCCH 2 has a particular bandwidth (BW 2) , which is illustrated as being centered around carrier frequency f ₂, although this is only an example. The transmission of the second UCI occurs in PUCCH 2 over a particular time duration t _d2, which may be scheduled. The time duration begins at a start time t _s2 and ends at an end time t _e2.
PUCCH 1 and PUCCH 2 are illustrated as occupying a similar amount of time-frequency resources, e.g. BW 1 and BW 2 are illustrated as being the same bandwidth (centered at different frequencies) and time duration t _d1 is illustrated as equal to time duration t _d2 (but having different start and end times) . This is only an example. PUCCH 1 and PUCCH 2 may occupy different amounts of resources in the time and/or frequency domain.
FIG. 7 illustrates an example in which there is a time gap t _gap between the end of PUCCH 1 and the start of PUCCH 2, i.e. between t _e1 and t _s2. The network might even purposely schedule such a time gap. However, because the transmission of PUCCH 1 and PUCCH 2 occurs on non-overlapping frequency resources on different carrier frequencies f ₁ and f ₂, and because there are two separate transmitter chains 404 and 424, the PUCCH 1 and PUCCH 2 could instead be transmitted by the UE 110 on partially or fully overlapping time resources. For example, FIG. 8 illustrates a variation of FIG. 7 in which there is an overlap in time t _overlap between the start of PUCCH 2 and the end of PUCCH 1. The overlap may occur for different reasons, e.g. it may be scheduled by the network, and/or possibly be a result of the uplink transmissions on the two different carrier frequencies f ₁ and f ₂ being unsynchronized.
As mentioned earlier, the provision of multiple transmitter chains at the UE 110 may be expensive, e.g. in terms of power consumption and/or occupying more physical space on the UE 110 (e.g. for heat dissipation) . For example, implementing two separate transmitter chains 404 and 424 may be expensive, e.g. in part due to the provision of two separate power amplifiers 412 and 432. Alternative embodiments are therefore disclosed below in which a single transmitter chain is used to transmit the first UCI on PUCCH 1 and the second UCI on PUCCH 2, through the use of time-division multiplexing. This may allow for a UE 110 having fewer transmitter chains (e.g. only a single transmitter chain) to operate in a scenario in which there are multiple different UCI to be transmitted that are associated with respective different cells, TRPs, and/or cell groups.
FIG. 9 illustrates UE 110 with only a single transmitter chain 504, according to one embodiment. The transmitter chain 504 includes a DAC 508, a frequency up-convertor 510, a power amplifier 512, and one or more antennas 514 (which may instead be panels) . Unlike the transmitter chains 404 and 424 illustrated in FIGs. 7 and 8, the transmitter chain 504 is able to switch between the two carrier frequencies f ₁ and f ₂, e.g. by using multiple RF oscillators. The switching may be implemented by a switch 520. The switching process requires a switching time t _switch associated with reconfiguring the transmitter chain 504 to be able to transmit on carrier frequency f ₂ instead of carrier frequency f ₁, and vice versa. The switching time t _switch may alternatively be referred to as the “switching duration” . In operation, the baseband processor 404 time-multiplexes the first UCI and the second UCI in the manner described herein. The first UCI is transmitted on PUCCH 1 by transmitter chain 504 on carrier frequency f ₁, and the second UCI is transmitted on PUCCH 2 by transmitter chain 504 on carrier frequency f ₂. A gap equal to or larger than the switching time t _switch must occur between transmitting first UCI on the carrier frequency f ₁ and transmitting second UCI on the carrier frequency f ₂, and vice versa.
In FIG. 9 an example is illustrated in which the first UCI on PUCCH 1 is transmitted to TRP 352 and the second UCI on PUCCH 2 is transmitted to TRP 372. The TRP 352 implements a receiver chain operating on carrier frequency f ₁, and the TRP 372 implements a receiver chain operating on carrier frequency f ₂. Alternatively, the first UCI and the second UCI may be transmitted to the same TRP, in which case that TRP would have the ability to receive transmissions on both carrier frequency f ₁ and carrier frequency f ₂, possibly through the implementation of two different receiver chains (one for carrier frequency f ₁ and the other for carrier frequency f ₂) , or by implementing a receiver chain able to switch between carrier frequency f ₁ and carrier frequency f ₂.
In FIG. 9 there is a time gap t _gap between the end of PUCCH 1 and the start of PUCCH 2. The time gap t _gap is assumed to be equal to or larger than the switching time t _switch. For example, the network may schedule the PUCCH 1 and PUCCH 2 in the time domain to have the time gap t _gap. However, in general this might not be the case, and example scenarios are discussed later in which different actions are taken by the UE 110 when there is overlap, no time gap, or not a big enough time gap between the end of PUCCH 1 and the start of PUCCH 2.
In some embodiments, the first UCI and the second UCI sent on the single transmitter chain 504 of FIG. 9 may be associated with respective different cells. A cell may refer to a carrier. In some embodiments, the first UCI and the second UCI sent on the single transmitter chain 504 of FIG. 9 may be associated with respective different cell groups. A cell group may refer to a group of carriers. In one example, the UE 110 may communicate on both a primary cell group and a secondary cell group. The primary cell group may be used to establish a connection with the network and communicate on both a user (data) plane and a control plane. The primary cell group may include a primary cell, which is a carrier used for initial access. The secondary cell group may be used to communicate on a user (data) plane but possibly not on a control plane. First UCI related to the primary cell group may be transmitted on a first uplink carrier having carrier frequency f ₁, and different second UCI related to the secondary cell group may be transmitted on a second uplink carrier having carrier frequency f ₂. In another example, the two cell groups might not necessarily be a primary cell group and a secondary cell group, e.g. both cell groups might each be a respective different secondary cell group. In any case, in some embodiments a cell group may have multiple downlink carriers, with a single uplink carrier used to transmit any UCI (e.g. HARQ feedback) associated with the downlink carriers of that cell group. For example, a single uplink carrier may transmit HARQ feedback for downlink transmissions received on the downlink carriers associated with that cell group. The single uplink carrier used to transmit the UCI for one cell group may be transmitted on the first uplink carrier at carrier frequency f ₁, and the single uplink carrier used to transmit the UCI for the other cell group may be transmitted on the second uplink carrier at carrier frequency f ₂.
In some embodiments, the first UCI and the second UCI sent on the single transmitter chain 504 of FIG. 9 may be associated with respective different PUCCH cell groups. A PUCCH cell group is a cell group in which there is a single uplink carrier for sending UCI (e.g. HARQ feedback) associated with any carriers in the PUCCH cell group. For example, the single uplink carrier may transmit HARQ feedback for downlink transmissions received on the downlink carriers in the PUCCH cell group. A first PUCCH cell group may have an uplink carrier having carrier frequency f ₁ for sending first UCI associated with that first PUCCH cell group, and a second PUCCH cell group may have an uplink carrier having carrier frequency f ₂ for sending second UCI associated with that second PUCCH cell group.
FIG. 10 illustrates a variation of FIG. 9 in which the single transmitter chain 504 can only transmit on carrier frequency f ₁ and not carrier frequency f ₂. The second UCI sent on PUCCH 2 is therefore not transmitted on carrier frequency f ₂, but instead on carrier frequency f ₁. The TRP 372 must be configured to receive the PUCCH 2 on carrier frequency f ₁. In one example, in response to the UE 110 transmitting a message (e.g. during initial access) indicating that the UE 110 has only a single transmitter chain operating on carrier frequency f ₁, the TRP 372 may be configured to use a receiver chain operating on carrier frequency f ₁ (instead of carrier frequency f ₂) to receive the second UCI on PUCCH 2.
In FIG. 10 an example is illustrated in which the first UCI on PUCCH 1 is transmitted to TRP 352 and the second UCI on PUCCH 2 is transmitted to TRP 372. The TRP 352 implements a receiver chain operating on carrier frequency f ₁, and the TRP 372 also implements a receiver chain operating on carrier frequency f ₁. Alternatively, the first UCI and the second UCI may be transmitted to the same TRP, in which case that TRP would receive both the first UCI on PUCCH 1 and the second UCI on PUCCH 2 on carrier frequency f ₁.
In some embodiments, the first UCI and the second UCI sent on the single transmitter chain 504 of FIG. 10 may be associated with respective different cells. A cell may refer to a carrier. In some embodiments, the first UCI and the second UCI sent on the single transmitter chain 504 of FIG. 10 may be associated with respective different cell groups. A cell group may refer to a group of carriers. In one example, the UE 110 may communicate on both a primary cell group and a secondary cell group. The primary cell group may be used to establish a connection with the network and communicate on both a user (data) plane and a control plane. The primary cell group may include a primary cell, which is a carrier used for initial access. The secondary cell group may be used to communicate on a user (data) plane but possibly not on a control plane. Both the first UCI related to the primary cell group and the second UCI related to the secondary cell group are transmitted on the same uplink carrier having carrier frequency f ₁. In another example, the two cell groups might not necessarily be a primary cell group and a secondary cell group, e.g. both cell groups might each be a respective different secondary cell group. In any case, in some embodiments a cell group may have multiple downlink carriers, with a single uplink carrier used to transmit any UCI (e.g. HARQ feedback) associated with the downlink carriers of that cell group. For example, a single uplink carrier may transmit HARQ feedback for downlink transmissions received on the downlink carriers associated with that cell group. The single uplink carrier used to transmit first UCI for one cell group may be transmitted on the first uplink carrier at carrier frequency f ₁, and the single uplink carrier used to transmit second UCI for the other cell group may also be transmitted on the on the first uplink carrier at carrier frequency f ₁. In some embodiments, the first UCI and the second UCI sent on the single transmitter chain 504 of FIG. 10 may be associated with respective different PUCCH cell groups. A PUCCH cell group is a cell group in which there is a single uplink carrier for sending UCI (e.g. HARQ feedback) associated with any carriers in the PUCCH cell group. For example, the single uplink carrier may transmit HARQ feedback for downlink transmissions received on the downlink carriers in the PUCCH cell group. A first PUCCH cell group may have an uplink carrier having carrier frequency f ₁ for sending first UCI associated with that first PUCCH cell group, and a second PUCCH cell group may have an uplink carrier also having carrier frequency f ₁ for sending second UCI associated with that second PUCCH cell group.
FIG. 11 illustrates another variation of FIG. 9 in which the single transmitter chain 504 can only transmit on carrier frequency f ₂ and not carrier frequency f ₁. The first UCI sent on PUCCH 1 is therefore not transmitted on carrier frequency f ₁, but instead on carrier frequency f ₂. The TRP 352 must be configured to receive the PUCCH 1 on carrier frequency f ₂. In one example, in response to the UE 110 transmitting a message (e.g. during initial access) indicating that the UE 110 has only a single transmitter chain operating on carrier frequency f ₂, the TRP 352 may be configured to use a receiver chain operating on carrier frequency f ₂ (instead of carrier frequency f ₁) to receive the first UCI on PUCCH 1.
In FIG. 11 an example is illustrated in which the first UCI on PUCCH 1 is transmitted to TRP 352 and the second UCI on PUCCH 2 is transmitted to TRP 372. The TRP 352 implements a receiver chain operating on carrier frequency f ₂, and the TRP 372 also implements a receiver chain operating on carrier frequency f ₂. Alternatively, the first UCI and the second UCI may be transmitted to the same TRP, in which case that TRP would receive both the first UCI on PUCCH 1 and the second UCI on PUCCH 2 on carrier frequency f ₂.
In some embodiments, the first UCI and the second UCI sent on the single transmitter chain 504 of FIG. 11 may be associated with respective different cells. A cell may refer to a carrier. In some embodiments, the first UCI and the second UCI sent on the single transmitter chain 504 of FIG. 11 may be associated with respective different cell groups. A cell group may refer to a group of carriers. In one example, the UE 110 may communicate on both a primary cell group and a secondary cell group. The primary cell group may be used to establish a connection with the network and communicate on both a user (data) plane and a control plane. The primary cell group may include a primary cell, which is a carrier used for initial access. The secondary cell group may be used to communicate on a user (data) plane but possibly not on a control plane. Both the first UCI related to the primary cell group and the second UCI related to the secondary cell group are transmitted on the same uplink carrier having carrier frequency f ₂. In another example, the two cell groups might not necessarily be a primary cell group and a secondary cell group, e.g. both cell groups might each be a respective different secondary cell group. In any case, in some embodiments a cell group may have multiple downlink carriers, with a single uplink carrier used to transmit any UCI (e.g. HARQ feedback) associated with the downlink carriers of that cell group. For example, a single uplink carrier may transmit HARQ feedback for downlink transmissions received on the downlink carriers associated with that cell group. The single uplink carrier used to transmit first UCI for one cell group may be transmitted on the second uplink carrier at carrier frequency f ₂, and the single uplink carrier used to transmit second UCI for the other cell group may also be transmitted on the on the second uplink carrier at carrier frequency f ₂. In some embodiments, the first UCI and the second UCI sent on the single transmitter chain 504 of FIG. 11 may be associated with respective different PUCCH cell groups. A PUCCH cell group is a cell group in which there is a single uplink carrier for sending UCI (e.g. HARQ feedback) associated with any carriers in the PUCCH cell group. For example, the single uplink carrier may transmit HARQ feedback for downlink transmissions received on the downlink carriers in the PUCCH cell group. A first PUCCH cell group may have an uplink carrier having carrier frequency f ₂ for sending first UCI associated with that first PUCCH cell group, and a second PUCCH cell group may have an uplink carrier also having carrier frequency f ₂ for sending second UCI associated with that second PUCCH cell group.
The embodiments in FIGs. 9 to 11 each assume that a time gap t _gap exists between the end of PUCCH 1 and the start of PUCCH 2, and in FIG. 9 the time gap t _gap is assumed to be equal to or larger than the time t _switch required for the transmitter chain 504 to switch between operating on carrier frequency f ₁ and carrier frequency f ₂.
FIG. 12 illustrates, more generally, an example of a situation in which there is a time gap t _gap between the end of PUCCH 1 and the start of PUCCH 2. The UE 110 is scheduled to transmit first UCI on PUCCH 1 on a first set of time-frequency resources, and the UE 110 is scheduled to transmit second UCI on PUCCH 2 on a second set of time-frequency resources. The frequency resources of PUCCH 1 and PUCCH 2 might or might not overlap, e.g. depending upon whether the single transmitter chain 504 transmits PUCCH 1 and PUCCH 2 on the same carrier frequency (e.g. as in FIGs. 10 and 11) or on two different carrier frequencies (e.g. as in FIG. 9) . In any case, the time resources of PUCCH 1 and PUCCH 2 do not overlap, and so the transmitter chain 504 may transmit all of PUCCH 1 and then all of PUCCH 2 in a time-multiplexed fashion without any overlap of symbols in PUCCH 1 and PUCCH 2. For example, in FIG. 12, PUCCH 1 is first transmitted by the transmitter chain 504, followed by PUCCH 2. The time gap t _gap may be zero or larger, and in FIG. 12 it is assumed that the time gap t _gap is at least as long as the switching time t _switch if the transmitter chain 504 has the ability to transmit PUCCH 1 and PUCCH 2 on different carrier frequencies (like in FIG. 9) .
In some embodiments, the uplink transmissions of first UCI on PUCCH 1 and second UCI on PUCCH 2 may be synchronized, e.g. on respective radio frames that have radio frame boundaries aligned in time. In such a situation, the network may have the ability to intentionally schedule time gap t _gap between the end of UE 110’s transmission of PUCCH 1 and the start of UE 110’s transmission of PUCCH 2, because the network knows the timing of when PUCCH 1 will be transmitted compared to PUCCH 2 due to the synchronization. For example, a downlink carrier on a primary cell may carry one or more messages having scheduling information that indicates, to the UE 110, when the UE 110 is to transmit PUCCH 1 and when the UE 110 is to transmit PUCCH 2. The scheduling information may provide a suitable time gap t _gap between the end of PUCCH 1 and the start of PUCCH 2, and because of synchronization of the uplink transmissions, that time gap will exist in the actual uplink transmissions sent by UE 110. The time gap t _gap may be zero or larger if PUCCH 1 and PUCCH 2 are transmitted on the same carrier frequency (like in FIGs. 10 and 11) , and the time gap t _gap may be equal to the switching time t _switch or larger if PUCCH 1 and PUCCH 2 are transmitted on different carrier frequencies (like in FIG. 9) . In some embodiments, one or more messages from the network may indicate the time gap explicitly, or instead the time gap may be indicated indirectly by indicating when PUCCH 2 is to start in relation to when PUCCH 1 is to end. In some embodiments, the time gap t _gap may be assigned in higher-layer signaling (such as RRC signaling) or in a MAC control element (CE) . In some embodiments, the time gap t _gap may be assigned in an information element (IE) , e.g. the CellGroupConfig IE.
However, there may be situations in which there is time overlap between when the UE 110 is scheduled to transmit the first UCI on PUCCH 1 and the second UCI on PUCCH 2. The time overlap may be due to multiple factors. Example factors may include one or both of the following:
(1) The network might not coordinate the PUCCH 1 and PUCCH 2 transmissions in time during scheduling because the network assumes that PUCCH 1 and PUCCH 2 are being transmitted on separate transmitter chains, e.g. in parallel on non-overlapping frequency resources. For example, scheduling information, or higher-layer signaling (e.g. RRC signaling) , or a MAC CE, or an IE, such as one or more CellGroupConfig IE (s) , may reveal that there is time overlap. The time overlap may be expressed as a time gap between the end of PUCCH 1 and the start of PUCCH 2 being less than zero. In some instances, the network might schedule a time gap of zero or greater between the end of PUCCH 1 and the start of PUCCH 2, but the transmitter chain 504 might need to switch carrier frequencies between transmission of PUCCH 1 and PUCCH 2 (like in FIG. 9) , and the time gap may be less than the switching time, i.e. t _gap<t _switch, such that there is time overlap.
(2) The network might schedule a time gap of zero or greater between the end of PUCCH 1 and the start of PUCCH 2, but a lack of synchronization in the different uplink transmission frames at the UE 110 may cause the PUCCH 1 and the PUCCH 2 to sometimes partially or fully overlap in time. In some instances, there might be a time gap between the end of PUCCH 1 and the start of PUCCH 2, but the transmitter chain 504 might need to switch carrier frequencies between transmission of PUCCH 1 and PUCCH 2 (like in FIG. 9) , and the time gap may be less than the switching time, i.e. t _gap<t _switch, such that there is time overlap.
Based on the local timing of when the UE 110 is to transmit PUCCH 1 and PUCCH 2, the UE 110 may determine, on a case-by-case basis, whether there will be time overlap between the transmission of PUCCH 1 and PUCCH 2 when the transmissions are time-multiplexed on the single transmitter chain 504. In some embodiments, for a given transmission of PUCCH 1 and PUCCH 2, the processor of UE 110 (e.g. baseband processor 402 or processor 210) determines whether there is time overlap based on the UE 110’s local clock of when the PUCCH 1 and PUCCH 2 are to be transmitted. If the time gap between the end of the transmission of one and the start of the transmission of the other is less than zero, then there is overlap. In general, sometimes there might be overlap and other times there might not be overlap.
FIG. 13 illustrates examples of time overlap and different rules that may be implemented by the UE 110, according to various scenarios. In FIG. 13, it is assumed that the UE 110 encounters a situation in which the first UCI on PUCCH 1 partially overlaps in time with the second UCI on PUCCH 2. In the example, the time overlap is a duration of time t _overlap over which the end portion of PUCCH 1 overlaps with the beginning portion of PUCCH 2. Even if PUCCH 1 and PUCCH 2 are transmitted on non-overlapping frequency resource (as in the case of FIG. 9) , the fact that PUCCH 1 and PUCCH 2 need to be transmitted by a single transmitter chain 504 in a time-multiplexed fashion means that the symbols of both PUCCH 1 and PUCCH 2 during t _overlap cannot both be transmitted. This overlap in time means that the UE 110 needs to implement a rule as to how to handle the situation. Various rules are possible, and the rule is known by both the UE 110 and the receiving device (e.g. the TRP (s) ) . For example, the rule may be configured in advance by the network, e.g. in a higher-layer control signaling (such as RRC signaling) or in a MAC CE sent from a TRP. A non-exhaustive list of possible rules that may be implemented are as follows:
Rule 1: The PUCCH having a first symbol later in time than the first symbol of the other PUCCH will not be fully transmitted. This is illustrated in scenario A of FIG. 13: PUCCH 1 starts first, and so all of PUCCH 1 is transmitted. The symbols of PUCCH 2 that overlap in time with PUCCH 1 (i.e. the symbols of PUCCH 2 in the duration t _overlap) are not transmitted. Therefore, in this scenario the second UCI in PUCCH 2 is only partially transmitted. The device receiving PUCCH 2 (e.g. a TRP) may still try to decode the second UCI, which may be successful depending upon the effectiveness of the forward error correction, the amount of second UCI missing, etc.
Rule 2: The PUCCH having a first symbol later in time than the first symbol of the other PUCCH will be fully transmitted. This is illustrated in scenario B of FIG. 13: PUCCH 2 starts later, and so all of PUCCH 2 is transmitted. The symbols of PUCCH 1 that overlap in time with PUCCH 2 (i.e. the symbols of PUCCH 1 in the duration t _overlap) are not transmitted. Therefore, in this scenario the first UCI in PUCCH 1 is only partially transmitted. The device receiving PUCCH 1 (e.g. a TRP) may still try to decode the first UCI, which may be successful depending upon the effectiveness of the forward error correction, the amount of first UCI missing, etc.
For Rule 1 and/or Rule 2: In some embodiments, if the first symbol of PUCCH 1 and the first symbol of PUCCH 2 are aligned in time, then the UE 110 is to transmit the PUCCH corresponding to the primary cell group. The primary cell group may be configured in higher layer signaling (such as RRC signaling) or in a MAC CE. An IE, such as pCellConfig, may be used to indicate the primary cell group. The primary cell group may sometimes instead be called the master cell group.
Rule 3: If there is overlap in time between PUCCH 1 and PUCCH 2, then the PUCCH associated with the primary cell group may be fully transmitted, and the overlapped symbols of the other PUCCH are not transmitted. Scenario A of FIG. 13 would be implemented if PUCCH 1 was associated with the primary cell group, and Scenario B of FIG. 13 would be implemented if the PUCCH 2 was associated with the primary cell group.
Rule 4: If there is overlap in time between PUCCH 1 and PUCCH 2, then the PUCCH associated with lower transmission power may be fully transmitted, and the overlapped symbols of the other PUCCH are not transmitted. Scenario A of FIG. 13 would be implemented if PUCCH 1 was associated with lower transmission power, and Scenario B of FIG. 13 would be implemented if the PUCCH 2 was associated with lower transmission power. The idea behind Rule 4 is that a PUCCH configured with lower transmission power may mean that the channel conditions of that PUCCH are better (e.g. higher signal-to-noise ratio (SNR) ) , such that it is likely that the PUCCH will be decoded and so should be fully transmitted. Lower transmission power might also mean that the transmission is less likely to interfere with the transmissions of other UEs. The opposite rule may instead be implemented: the PUCCH associated with higher transmission power is fully transmitted, e.g. because that PUCCH may carry more important information, or the channel conditions for that PUCCH are not as good and so omitting some of that PUCCH will cause the receiver to likely fail at decoding the PUCCH. In some embodiments, if the transmission power of PUCCH 1 and PUCCH 2 is the same, then Rule 3 may be implemented.
Rule 5: Overlap in time between PUCCH 1 and PUCCH 2 results in only one of PUCCH 1 or PUCCH 2 being transmitted, and the other is not transmitted at all. This is the case in scenarios C and D of FIG. 13. The PUCCH that is transmitted may depend upon: which PUCCH started earlier (e.g. the PUCCH that starts first is transmitted and the other PUCCH is not) ; and/or which PUCCH started later (e.g. the PUCCH that starts later is transmitted and the other PUCCH is not) ; and/or which PUCCH is associated with a primary cell group (e.g. the PUCCH associated with the primary cell group is transmitted and the PUCCH associated with the secondary cell group is not transmitted) . In some embodiments, if the time overlap is less than a predetermined threshold (e.g. the duration of t _overlap is small) , then Rule 1, 2, 3, or 4 is followed, but once the time overlap is more than the predetermined threshold (e.g. the duration of t _overlap is large) , then Rule 5 is followed. This is because if the overlap is too large then it might not be worth transmitting a partial PUCCH because that partial PUCCH might not be decodable.
In some embodiments, the network configures the UE 110 to transmit only the first UCI or the second UCI when there is time overlap.
In some embodiments, the network may configure the UE 110 to send only a single PUCCH (not both PUCCH 1 and PUCCH 2) . The single PUCCH might be configured to carry both the first UCI and the second UCI, or the network may configure the UE 110 to carry only the first UCI or the second UCI, e.g. the network may configure the UE 110 (e.g. via a message sent from a TRP) to carry only the UCI associated with the primary cell group. Configuring whether the single PUCCH is to carry both first and second UCI, or only the first UCI, or only the second UCI, may occur semi-statically or dynamically. For example, the configuration may be indicated in RRC signaling from a TRP, or in a MAC CE from a TRP, or in DCI from a TRP, and the configuration may change over time. In such an implementation, it may be that the transmitter chain 504 does not switch carrier frequencies, but instead transmits the single PUCCH on just carrier frequency f ₁ (like in FIG. 10) or carrier frequency f ₂ (like in FIG. 11) . In other implementations, the transmitter chain 504 may be able to switch carrier frequencies (like in FIG. 9) , and the network may configure the UE 110 (e.g. via a message sent from a TRP) to use either carrier frequency f ₁ or carrier frequency f ₂ to send the single PUCCH. The configuration may occur semi-statically (e.g. in RRC signaling or a MAC CE) or dynamically (e.g. in DCI) .
Consider next the scenario in which both PUCCH 1 and PUCCH 2 are transmitted by the single transmitter chain 504, and the transmitter chain 504 is configured transmit PUCCH 1 on carrier frequency f ₁ and PUCCH 2 on carrier frequency f ₂, like in FIG. 9. The switching time t _switch must be taken into account, such that some of PUCCH 1 or PUCCH 2 might not be transmitted even if there is a time gap between the end of PUCCH 1 and the start of PUCCH 2. FIG. 14 illustrates an example in which the time gap between the end of PUCCH 1 and the start of PUCCH 2 is greater than or equal to the switching time, according to one embodiment. That is, t _switch≤t _gap. In this instance, the transmitter chain 504 has time to switch from carrier frequency f ₁ to carrier frequency f ₂ during the t _gap, and so all of the first UCI on PUCCH 1 and all of the second UCI on PUCCH 2 can be transmitted in a time-multiplexed manner with no overlap in the time domain, as illustrated in Scenario A of FIG. 14.
FIGs. 15 and 16 illustrate scenarios in which the time gap between the end of PUCCH 1 and the start of PUCCH 2 is less than the switching time, i.e. t _switch>t _gap. One of Rules 1 to 5 discussed above is implemented for the overlapped portion corresponding to the duration of time between when the time gap ends and when the switching duration ends, i.e. the duration t _switch-t _gap.
Scenario B of FIG. 15 corresponds to the situation in which all of PUCCH 1 is transmitted and the overlapped portion of PUCCH 2 (shown by a cross-hatched box 602) is not transmitted. Scenario B of FIG. 15 may, for example, correspond to Rule 1, Rule 3 (where PUCCH 1 is associated with the primary cell group) , or Rule 4 (where PUCCH 1 is associated with lower transmission power) .
Scenario C of FIG. 15 corresponds to the situation in which all of PUCCH 2 is transmitted and the overlapped portion of PUCCH 1 (shown by a cross-hatched box 604) is not transmitted. Scenario C of FIG. 15 may, for example, correspond to Rule 2, Rule 3 (where PUCCH 2 is associated with the primary cell group) , or Rule 4 (where PUCCH 2 is associated with lower transmission power) .
Scenarios D and E of FIG. 16 corresponds to the situation in which the overlap in time between PUCCH 1 and PUCCH 2 results in only one of PUCCH 1 or PUCCH 2 being transmitted, and the other is not transmitted at all. Scenarios D and E of FIG. 16 may, for example, correspond to Rule 5.
In all of the embodiments described above in relation to FIGs. 9 to 16, it may be the case that the PUCCH 1 carries UCI for a primary TRP and/or primary cell group (which may alternatively be referred to as a master TRP /master cell group) . It may also be the case that the PUCCH 2 carries UCI for a secondary TRP and/or secondary cell group. In some embodiments, “cell” means “carrier” , a cell group has one or multiple carriers, and communication between UE 110 and the network may occur on a primary cell group (which has a user/data plane and a control plane) and a secondary cell group (which has the user/data plane only) . Within the primary cell group there may be a primary cell, which is the cell used for initial access. A PUCCH cell group means there is one PUCCH carrier for sending UCI related to all downlink transmissions associated with that PUCCH cell group. In some embodiments, PUCCH 1 carries UCI for the primary cell group, e.g. in a first PUCCH cell group, such that the UCI on PUCCH 1 relates to all downlink transmissions received in that cell group, such as HARQ feedback for those downlink transmissions. In some embodiments, the PUCCH 2 carriers UCI for the secondary cell group, e.g. in a second PUCCH cell group, such that the UCI on PUCCH 2 relates to all downlink transmissions received in that cell group, such as HARQ feedback for those downlink transmissions.
In any of the embodiments described above in relation to FIGs. 9 to 16, it may be that one, some, or all of the physical layer parameters for PUCCH 1 and PUCCH2 may be separately configured. For example, a message from a TRP may separately configure power control parameters and/or PUCCH format and/or PUCCH time resources and/or PUCCH frequency resources for PUCCH 1 and PUCCH 2.
Any of the embodiments described above in relation to FIGs. 9 to 16 may be modified such that the control information is not necessarily UCI sent on a PUCCH. Instead, the control information may be sent to another UE, e.g. on a sidelink channel. As an example, PUCCH 1 may be replaced with a first control channel carrying first control information, possibly destined for another UE. As another example, PUCCH 2 may also or instead be replaced with a second control channel carrying second control information, possibly destined for another UE (which might be the same as the UE the first control information is sent to, if the first control information is also sent to a UE) .
In some embodiments, the UE 110 indicates to the network the transmitter chain capabilities of the UE 110, e.g. whether the UE 110 has two separate transmitter chains 404 and 424 (as in FIGs. 7 and 8) or whether the UE 110 has a single transmitter chain 504. If the UE 110 has a single transmitter chain 504, the UE 110 may indicate whether the UE 110 can transmit on multiple uplink carrier frequencies (like in FIG. 9) or only a single uplink carrier frequency (like in FIGs. 10 and 11) . For example, the transmitter chain capabilities of the UE 110 may be indicated in a capability report, e.g. during initial access in a message sent to a TRP. Depending upon the UE 110’s reported capability, the network may configure the UE 110 appropriately. For example, if the UE 110 indicates that the UE 110 has two transmitter chains 404 and 424, then the network will not configure the UE 110 with a time-multiplexing rule, and the network might not have regard to whether the scheduled PUCCH 1 and PUCCH 2 overlap in time. Whereas if the UE 110 indicates that the UE 110 has only a single transmitter chain 504, then the network may instruct the TRP to send a configuration message to the UE 110 that configures a time-division multiplexing rule for if there is overlap, such as any of Rules 1 to 5 described above. The network may also intentionally schedule a time gap of zero or greater between the end of one PUCCH and the start of the next PUCCH.
FIG. 17 illustrates a method performed by an apparatus and a device, according to one embodiment. The apparatus may be an ED 110, e.g. a UE, although not necessarily. The device may be a network device, e.g. a TRP, although not necessarily.
Optionally, at step 702, the apparatus transmits, to the device, an indication that the apparatus has a single transmitter chain to support transmission of first control information and second control information. The first control information may be associated with at least one of:a first TRP, a first cell, a first cell group, or a first PUCCH cell group. The second control information may be associated with at least one of: a different second TRP, a different second cell, a different second cell group, or a different second PUCCH cell group. At optional step 704, the device receives the indication from the apparatus.
Optionally, at step 706, in response to receiving the indication in step 704, the device transmits a message to the apparatus. The message configures the apparatus to perform time-division multiplexing of the first control information and the second control information to transmit some or all of the first control information and some or all of the second control information using the single transmitter chain. At optional step 708, the apparatus receives the message.
At step 710, the apparatus transmits some or all of first control information using the transmitter chain. The first control information may be associated with at least one of: a first TRP, a first cell, a first cell group, or a first PUCCH cell group. At step 712, the apparatus transmits some or all of second control information using the same transmitter chain as the transmitter chain used to transmit the some or all of the first control information. The second control information may be associated with at least one of: a different second TRP, a different second cell, a different second cell group, or a different second PUCCH cell group.
The first control information that is transmitted is time-division multiplexed with the second control information that is transmitted. The first and second control information do not necessarily need to be transmitted to the device, e.g. if the device is a network device configuring the apparatus, but the control information is meant for another UE.
In some embodiments in the method of FIG. 17, the first control information is first uplink control information, i.e. first UCI, which may be transmitted on a first physical layer control channel, e.g. a first PUCCH. In some embodiments in the method of FIG. 17, the second control information is second uplink control information, i.e. second UCI, which may be transmitted on a second physical layer control channel, e.g. a second PUCCH. Such is the case in the examples explained earlier in relation to FIGs. 9 to 16, and any of the implementations and variations discussed in relation to any of FIGs. 9 to 16 may be incorporated into the method of FIG. 17. Note that uplink is sometimes referred to as “transmission link” . Therefore, “uplink” may instead be called “transmission link” herein in an interchangeable fashion, e.g. uplink control information may be called transmission link control information and/or an uplink carrier may be called a transmission link carrier.
In some embodiments of the method of FIG. 17, the transmitter chain of the apparatus comprises an antenna port or a transmit antenna.
In some embodiments, the first TRP and/or second TRP mentioned above in FIG. 17 may be a T-TRP, e.g. a Node B. For example, the first TRP may be a first Node B and the second TRP may be a second Node B. In some embodiments, a NodeB may refer to a wireless network node which communicates with a wireless device or a user equipment. For example, a NodeB may be a base station or an eNB/gNB.
From the perspective of the apparatus, the following are additional embodiments in relation to FIG. 17. The following additional embodiments assume that the first control information is first uplink control information and that the second control information is second uplink control information. However, this is not necessary. The embodiments below still apply even if the first and/or second control information is not uplink control information.
In some embodiments, in response to presence of a time gap of a predetermined duration between an end of the first uplink control information and a start of the second uplink control information, the apparatus transmits all of the first uplink control information and all of the second uplink control information using the transmitter chain. Examples are described earlier in relation to FIGs. 9 to 12, and 14. Any of the implementations and variations described earlier in relation to FIGs. 9 to 12 and 14 may be incorporated into the method of FIG. 17. In some embodiments, the first uplink control information and the second uplink control information are transmitted at a same carrier frequency (e.g. like in FIGs. 10 and 11) , and the predetermined duration is zero or larger (e.g. the predetermined duration may be time gap t _gap discussed earlier, e.g. in relation to FIGs. 10 and 11) . In some embodiments, the first uplink control information and the second uplink control information are transmitted at different carrier frequencies (e.g. like in FIGs. 9 and 14) , and the predetermined duration is equal to a carrier frequency switching duration or larger (e.g. the predetermined duration may be switching time t _switch discussed earlier, e.g. in relation to FIGs. 9 and 14) .
In some embodiments, in response to an overlap in time between a first portion of the first uplink control information and a second portion of the second uplink control information, the apparatus transmits the first portion of the first uplink control information using the transmitter chain and does not transmit the second portion of the second uplink control information. Examples are described earlier in relation to FIGs. 13, 15, and 16. Any of the implementations and variations described earlier in relation to FIGs. 13, 15, and 16 may be incorporated into the method of FIG. 17. In some embodiments, the first uplink control information begins transmission earlier in time than the second uplink control information, e.g. like in Scenario A of FIG. 13. In some embodiments, the first uplink control information begins transmission later in time than the second uplink control information, e.g. like in Scenario B of FIG. 13 (assuming in this scenario that the “first uplink control information” is the second UCI sent in PUCCH 2 in FIG. 13) . In some embodiments, the first uplink control information is associated with a primary cell group. In some embodiments, the first uplink control information is associated with lower transmit power. In some embodiments, the apparatus may receive a message configuring the apparatus to transmit the first portion and not the second portion in response to the overlap in time between the first portion and the second portion.
From the perspective of the device, the following are additional embodiments in relation to FIG. 17. The following additional embodiments assume that the first control information is first uplink control information and that the second control information is second uplink control information. However, this is not necessary. The embodiments below still apply even if the first and/or second control information is not uplink control information.
In some embodiments, the message in step 706 is transmitted from the first TRP. In some embodiments, some or all of the first uplink control information is received at the first TRP. In some embodiments, some or all of the second uplink control information is received at the second TRP.
In some embodiments, the message transmitted at step 706 configures the apparatus to transmit a first portion of the first uplink control information and not transmit a second portion of the second uplink control information in response to an overlap in time between the first portion of the first uplink control information and the second portion of the second uplink control information. Examples are described earlier in relation to FIGs. 13, 15, and 16. Any of the implementations and variations described earlier in relation to FIGs. 13, 15, and 16 may be incorporated into the method of FIG. 17. In some embodiments, the first uplink control information may be associated with a primary cell group. In some embodiments, the first uplink control information may be associated with lower transmit power.
In some embodiments, the method of FIG. 17 may include the device transmitting at least one message configuring first physical layer parameters for transmission of the first uplink control information and configuring different second physical layer parameters for transmission of the second uplink control information.
In some embodiments, some or all of the first uplink control information is received on a first carrier, and some or all of the second uplink control information is received on a second different carrier. In other embodiments, some or all of the first uplink control information and some or all of the second uplink control information is received on a same carrier.
Examples of an apparatus (e.g. ED or UE) and a device (e.g. TRP) to perform the various methods described herein are also disclosed.
The apparatus may include a memory to store processor-executable instructions, and at least one processor to execute the processor-executable instructions. When the processor executes the processor-executable instructions, the processor may be caused to perform the method steps of the apparatus as described herein, e.g. in relation to FIG. 17. As one example, the at least one processor may output, for transmission on a transmitter chain, some or all of first control information, and output, for transmission on that same transmitter chain, some or all of second control information, where the first control information to be transmitted is time-division multiplexed with the second control information to be transmitted.
The device may include a memory to store processor-executable instructions, and at least one processor to execute the processor-executable instructions. When the at least one processor executes the processor-executable instructions, the at least one processor may be caused perform the method steps of the device as described above, e.g. in relation to FIG. 17. For example, the processor may receive an indication that an apparatus has a single transmitter chain to support transmission of the first control information and the second control information. The indication may be received by receiving it at the input of the processor, e.g. the indication may be received in a signal at a TRP and that signal (or a processed version of that signal) may be forwarded to the processor for obtaining the indication. The indication may be obtained by the processor decoding the signal. As another example, the processor may output a message for transmission to the apparatus, the message configuring the apparatus to perform time-division multiplexing of the first control information and the second control information. As another example, the processor may subsequently receive, from the apparatus, some or all of the first control information and some or all of the second control information. The first and second control information may be received at an input of the processor. For example, the first and second control information may be time-multiplexed on one or more signals transmitted from the apparatus and received at one or more TRPs. The received signal (s) are then forwarded to the processor, possibly after processing of the signal (s) . The signal (s) are then used to obtain the control information in the processor. The obtaining may include decoding the signal (s) to obtain the control information.
Technical benefits of some embodiments herein include an apparatus (such as UE 110) not needing to implement two transmitter chains to support DC and CA with two PUCCH groups. The potential benefit of DC and CA with two cell groups in commercial wireless networks may still be achieved because the UE may still support, using the single transmitter chain, DC and CA with two PUCCH cell groups.
Note that the expression “at least one of A or B” , as used herein, is interchangeable with the expression “A and/or B” . It refers to a list in which you may select A or B or both A and B. Similarly, “at least one of A, B, or C” , as used herein, is interchangeable with “A and/or B and/or C” or “A, B, and/or C” . It refers to a list in which you may select: A or B or C, or both A and B, or both A and C, or both B and C, or all of A, B and C. The same principle applies for longer lists having a same format.
Although the present invention has been described with reference to specific features and embodiments thereof, various modifications and combinations can be made thereto without departing from the invention. The description and drawings are, accordingly, to be regarded simply as an illustration of some embodiments of the invention as defined by the appended claims, and are contemplated to cover any and all modifications, variations, combinations or equivalents that fall within the scope of the present invention. Therefore, although the present invention and its advantages have been described in detail, various changes, substitutions and alterations can be made herein without departing from the invention as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the disclosure of the present invention, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed, that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized according to the present invention. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.
Moreover, any module, component, or device exemplified herein that executes instructions may include or otherwise have access to a non-transitory computer/processor readable storage medium or media for storage of information, such as computer/processor readable instructions, data structures, program modules, and/or other data. A non-exhaustive list of examples of non-transitory computer/processor readable storage media includes magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, optical disks such as compact disc read-only memory (CD-ROM) , digital video discs or digital versatile disc (DVDs) , Blu-ray Disc ^TM, or other optical storage, volatile and non-volatile, removable and non-removable media implemented in any method or technology, random-access memory (RAM) , read-only memory (ROM) , electrically erasable programmable read-only memory (EEPROM) , flash memory or other memory technology. Any such non-transitory computer/processor storage media may be part of a device or accessible or connectable thereto. Any application or module herein described may be implemented using computer/processor readable/executable instructions that may be stored or otherwise held by such non-transitory computer/processor readable storage media.

Claims

A method performed by an apparatus, the method comprising:

transmitting some or all of first uplink control information using a transmitter chain, the first uplink control information associated with at least one of: a first transmit and receive point (TRP) , a first cell, a first cell group, or a first physical uplink control channel (PUCCH) cell group;

transmitting some or all of second uplink control information using a same transmitter chain as the transmitter chain used to transmit the some or all of the first uplink control information, the second uplink control information associated with at least one of: a different second TRP, a different second cell, a different second cell group, or a different second PUCCH cell group;

wherein the first uplink control information that is transmitted is time-division multiplexed with the second uplink control information that is transmitted.
The method of claim 1, further comprising:

in response to presence of a time gap of a predetermined duration between an end of the first uplink control information and a start of the second uplink control information: transmitting all of the first uplink control information and all of the second uplink control information using the transmitter chain.
The method of claim 2, wherein the first uplink control information and the second uplink control information are transmitted at a same carrier frequency, and wherein the predetermined duration is zero or larger.
The method of claim 2, wherein the first uplink control information and the second uplink control information are transmitted at different carrier frequencies, and wherein the predetermined duration is equal to a carrier frequency switching duration or larger.
The method of any one of claims 1 to 4, further comprising:

in response to an overlap in time between a first portion of the first uplink control information and a second portion of the second uplink control information: transmitting the first portion of the first uplink control information using the transmitter chain and not transmitting the second portion of the second uplink control information.
The method of claim 5, further comprising:

receiving a message configuring the apparatus to transmit the first portion and not the second portion in response to the overlap in time between the first portion and the second portion.
The method of claim 5 or claim 6, wherein the first uplink control information begins transmission earlier in time than the second uplink control information.
The method of claim 5 or claim 6, wherein the first uplink control information begins transmission later in time than the second uplink control information.
The method of claim 5 or claim 6, wherein the first uplink control information is associated with a primary cell group.
The method of claim 5 or claim 6, wherein the first uplink control information is associated with lower transmit power.
The method of any one of claims 1 to 10, wherein the transmitter chain comprises an antenna port or a transmit antenna.
The method of any one of claims 1 to 11, wherein the first TRP is a first Node B and the second TRP is a second Node B.
The method of claim 1 or claim 2, wherein the first uplink control information that is transmitted using the transmitter chain is transmitted on a first carrier frequency, wherein the second uplink control information that is transmitted using the transmitter chain is transmitted on a second carrier frequency, and wherein the method further comprises:

switching the transmitter chain from the first carrier frequency to the second carrier frequency subsequent to transmitting the first uplink control information and prior to transmitting the second uplink control information.
The method of claim 1 or claim 2, wherein the first uplink control information and the second uplink control information are transmitted on a same carrier frequency.
The method of any one of claims 1 to 14, further comprising:

receiving at least one message configuring first physical layer parameters for transmission of the first uplink control information and different second physical layer parameters for transmission of the second uplink control information;

wherein the first uplink control information that is transmitted is transmitted using the first physical layer parameters, and the second uplink control information that is transmitted is transmitted using the second physical layer parameters.
The method of any one of claims 1 to 15, further comprising:

obtaining third uplink control information associated with at least one of: the first TRP, the first cell, the first cell group, or the first PUCCH cell group;

obtaining fourth uplink control information associated with at least one of: the different second TRP, the different second cell, the different second cell group, or the different second PUCCH cell group;

in response to an overlap in time between some or all of the third uplink control information and some or all the fourth uplink control information: transmitting the third uplink control information using the transmitter chain and not transmitting the fourth uplink control information.
An apparatus comprising:

at least one processor; and

a memory storing processor-executable instructions that, when executed, cause the at least one processor to:

output, for transmission on a transmitter chain, some or all of first uplink control information, the first uplink control information associated with at least one of: a first transmit and receive point (TRP) , a first cell, a first cell group, or a first physical uplink control channel (PUCCH) cell group;

output, for transmission on a same transmitter chain as the transmitter chain used to transmit the some or all of the first uplink control information, some or all of second uplink control information, the second uplink control information associated with at least one of: a different second TRP, a different second cell, a different second cell group, or a different second PUCCH cell group;

wherein the first uplink control information to be transmitted is time-division multiplexed with the second uplink control information to be transmitted.
The apparatus of claim 17, wherein in response to presence of a time gap of a predetermined duration between an end of the first uplink control information and a start of the second uplink control information: the at least one processor is to output, for transmission on the transmitter chain, all of the first uplink control information and all of the second uplink control information.
The apparatus of claim 18, wherein the first uplink control information and the second uplink control information are for transmission on at a same carrier frequency, and wherein the predetermined duration is zero or larger.
The apparatus of claim 18, wherein the first uplink control information and the second uplink control information are for transmission on different carrier frequencies, and wherein the predetermined duration is equal to a carrier frequency switching duration or larger.
The apparatus of any one of claims 17 to 20, wherein in response to an overlap in time between a first portion of the first uplink control information and a second portion of the second uplink control information, the at least one processor is to: (i) output, for transmission on the transmitter chain, the first portion of the first uplink control information and (ii) not output for transmission on the transmitter chain, the second portion of the second uplink control information.
The apparatus of claim 21, wherein the at least one processor is to receive a message configuring the apparatus to transmit the first portion and not the second portion in response to the overlap in time between the first portion and the second portion.
The apparatus of claim 21 or claim 22, wherein the first uplink control information begins transmission earlier in time than the second uplink control information.
The apparatus of claim 21 or claim 22, wherein the first uplink control information begins transmission later in time than the second uplink control information.
The apparatus of claim 21 or claim 22, wherein the first uplink control information is associated with a primary cell group.
The apparatus of claim 21 or claim 22, wherein the first uplink control information is associated with lower transmit power.
The apparatus of any one of claims 17 to 26, wherein the transmitter chain comprises an antenna port or a transmit antenna.
The apparatus of any one of claims 17 to 27, wherein the first TRP is a first Node B and the second TRP is a second Node B.
The apparatus of claim 17 or claim 18, wherein the first uplink control information is for transmission on a first carrier frequency, wherein the second uplink control information is for transmission on a second carrier frequency, and wherein the apparatus is to switch the transmitter chain from the first carrier frequency to the second carrier frequency subsequent to transmission of the first uplink control information and prior to transmission of the second uplink control information.
The apparatus of claim 17 or claim 18, wherein the first uplink control information and the second uplink control information are for transmission on a same carrier frequency.
The apparatus of any one of claims 17 to 30, wherein the at least one processor is to: receive at least one message configuring first physical layer parameters for transmission of the first uplink control information and different second physical layer parameters for transmission of the second uplink control information; and wherein the first uplink control information is for transmission using the first physical layer parameters, and the second uplink control information is for transmission using the second physical layer parameters.
The apparatus of any one of claims 17 to 31, wherein the at least one processor is to:

obtain third uplink control information associated with at least one of: the first TRP, the first cell, the first cell group, or the first PUCCH cell group;

obtain fourth uplink control information associated with at least one of: the different second TRP, the different second cell, the different second cell group, or the different second PUCCH cell group;

in response to an overlap in time between some or all of the third uplink control information and some or all the fourth uplink control information: output the third uplink control information for transmission on the transmitter chain, and not output the fourth uplink control information for transmission on the transmitter chain.
A method performed by a device, the method comprising:

receiving, from an apparatus, an indication that the apparatus has a single transmitter chain to support transmission of first uplink control information and second uplink control information, wherein the first uplink control information is associated with at least one of: a first transmit and receive point (TRP) , a first cell, a first cell group, or a first physical uplink control channel (PUCCH) cell group; and wherein the second uplink control information associated with at least one of: a different second TRP, a different second cell, a different second cell group, or a different second PUCCH cell group;

in response to receiving the indication: transmitting a message for the apparatus, the message configuring the apparatus to perform time-division multiplexing of the first uplink control information and the second uplink control information to transmit some or all of the first uplink control information and some or all of the second uplink control information using the single transmitter chain;

subsequently receiving, from the apparatus, the some or all of the first uplink control information and the some or all of the second uplink control information.
The method of claim 33, wherein the message is transmitted from the first TRP, wherein the some or all of the first uplink control information is received at the first TRP, and wherein the some or all of the second uplink control information is received at the second TRP.
The method of claim 33 or claim 34, wherein the message configures the apparatus to transmit a first portion of the first uplink control information and not transmit a second portion of the second uplink control information in response to an overlap in time between the first portion of the first uplink control information and the second portion of the second uplink control information.
The method of claim 35, wherein the first uplink control information is associated with a primary cell group.
The method of claim 35, wherein the first uplink control information is associated with lower transmit power.
The method of any one of claims 33 to 37, further comprising transmitting at least one message configuring first physical layer parameters for transmission of the first uplink control information and configuring different second physical layer parameters for transmission of the second uplink control information.
The method of any one of claims 33 to 38, wherein the some or all of the first uplink control information is received on a first carrier, and the some or all of the second uplink control information is received on a second different carrier.
The method of any one of claims 33 to 38, wherein the some or all of the first uplink control information and the some or all of the second uplink control information is received on a same carrier.
The method of any one of claims 33 to 40, wherein the single transmitter chain comprises an antenna port or a transmit antenna.
The method of any one of claims 33 to 41, wherein the first TRP is a first Node B and the second TRP is a second Node B.
A device comprising:

at least one processor; and

a memory storing processor-executable instructions that, when executed, cause the at least one processor to:

receive an indication that an apparatus has a single transmitter chain to support transmission of first uplink control information and second uplink control information, wherein the first uplink control information is associated with at least one of: a first transmit and receive point (TRP) , a first cell, a first cell group, or a first physical uplink control channel (PUCCH) cell group; and wherein the second uplink control information associated with at least one of: a different second TRP, a different second cell, a different second cell group, or a different second PUCCH cell group;

in response to receiving the indication: output a message for transmission to the apparatus, the message configuring the apparatus to perform time-division multiplexing of the first uplink control information and the second uplink control information to transmit some or all of the first uplink control information and some or all of the second uplink control information using the single transmitter chain;

subsequently receive, from the apparatus, the some or all of the first uplink control information and the some or all of the second uplink control information.
The device of claim 43, wherein the message is for transmission by the first TRP, wherein the some or all of the first uplink control information is to be received at the first TRP, and wherein the some or all of the second uplink control information is to be received at the second TRP.
The device of claim 43 or claim 44, wherein the message configures the apparatus to transmit a first portion of the first uplink control information and not transmit a second portion of the second uplink control information in response to an overlap in time between the first portion of the first uplink control information and the second portion of the second uplink control information.
The device of claim 45, wherein the first uplink control information is associated with a primary cell group.
The device of claim 45, wherein the first uplink control information is associated with lower transmit power.
The device of any one of claims 43 to 47, wherein the at least one processor is to output, for transmission, at least one message configuring first physical layer parameters for transmission of the first uplink control information and configuring different second physical layer parameters for transmission of the second uplink control information.
The device of any one of claims 43 to 48, wherein the some or all of the first uplink control information is to be received on a first carrier, and the some or all of the second uplink control information is to be received on a second different carrier.
The device of any one of claims 43 to 48, wherein the some or all of the first uplink control information and the some or all of the second uplink control information is to be received on a same carrier.
The device of any one of claims 43 to 50, wherein the single transmitter chain comprises an antenna port or a transmit antenna.
The device of any one of claims 43 to 51, wherein the first TRP is a first Node B and the second TRP is a second Node B.