WO2024069043A1

WO2024069043A1 - Indication for uplink transmission using multiple antenna arrangements simultaneously

Info

Publication number: WO2024069043A1
Application number: PCT/FI2023/050511
Authority: WO
Inventors: Juha Pekka Karjalainen; Sami-Jukka Hakola; Timo Koskela; Mihai Enescu; Youngsoo Yuk
Original assignee: Nokia Technologies Oy
Priority date: 2022-09-30
Filing date: 2023-09-07
Publication date: 2024-04-04

Abstract

Disclosed is a method comprising receiving, from a network element, downlink control information for scheduling a physical uplink shared channel transmission (510), determining whether the received downlink control information comprises first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission (520), wherein, if it is determined that the received downlink control information comprises the first antenna port information and the second antenna port information, then the method further comprises performing the scheduled physical uplink shared channel transmission through a first antenna arrangement based on the first antenna port information, and through a second antenna arrangement based on the second antenna port information (535).

Description

Indication for Uplink Transmission using Multiple Antenna Arrangements Simultaneously

Field

The following exemplary embodiments relate to wireless communication and transmitting an uplink transmission with one or more transmission antenna arrangements.

Background

Wireless communication networks, such as cellular communication networks are to transmit high data rates, which occur for example during peak times. Multiple input multiple output enhancements may be used to allow higher data rates to be transmitted. Reliability of downlink and also uplink transmissions are also aspects of great interest and thus enhancements to those are desirable.

Brief Description

The scope of protection sought for various embodiments of the invention is set out by the independent claims. The exemplary embodiments and features, if any, described in this specification that do not fall under the scope of the independent claims are to be interpreted as examples useful for understanding various embodiments of the invention.

According to a first aspect there is provided an apparatus comprising means for receiving, from a network element, downlink control information for scheduling a physical uplink shared channel transmission, means for determining whether the received downlink control information comprises first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, means for performing the scheduled physical uplink shared channel transmission wherein, if it is determined that the received downlink control information comprises the first antenna port information and the second antenna port information, then the means are configured to perform the scheduled physical uplink shared channel transmission through a first antenna arrangement based on the first antenna port information, and through a second antenna arrangement based on the second antenna port information.

In some example embodiments according to the first aspect, the means comprises at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, to cause the performance of the apparatus.

According to a second aspect there is provided an apparatus comprising at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, to cause the apparatus at least to: receive, from a network element, downlink control information for scheduling a physical uplink shared channel transmission, determine whether the received downlink control information comprises first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, wherein, if it is determined that the received downlink control information comprises the first antenna port information and the second antenna port information, then the apparatus is further caused to perform the scheduled physical uplink shared channel transmission through a first antenna arrangement of the apparatus based on the first antenna port information, and through a second antenna arrangement of the apparatus based on the second antenna port information.

According to a third aspect there is provided a method comprising: receiving, from a network element, downlink control information for scheduling a physical uplink shared channel transmission, determining whether the received downlink control information comprises first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, wherein, if it is determined that the received downlink control information comprises the first antenna port information and the second antenna port information, then the method further comprises performing the scheduled physical uplink shared channel transmission through a first antenna arrangement based on the first antenna port information, and through a second antenna arrangement based on the second antenna port information.

In some example embodiments according to the third aspect, the method is a computer-implemented method.

According to a fourth aspect there is provided a computer program comprising instructions for causing an apparatus to perform at least the following: receive, from a network element, downlink control information for scheduling a physical uplink shared channel transmission, determine whether the received downlink control information comprises first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, wherein, if it is determined that the received downlink control information comprises the first antenna port information and the second antenna port information, then the apparatus is further caused to perform the scheduled physical uplink shared channel transmission through a first antenna arrangement of the apparatus based on the first antenna port information, and through a second antenna arrangement of the apparatus based on the second antenna port information.

According to a fifth aspect there is provided a computer program comprising instructions stored thereon for performing at least the following: receiving, from a network element, downlink control information for scheduling a physical uplink shared channel transmission, determining whether the received downlink control information comprises first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, wherein, if it is determined that the received downlink control information comprises the first antenna port information and the second antenna port information, then the computer program further comprises instructions stored thereon for performing the scheduled physical uplink shared channel transmission through a first antenna arrangement based on the first antenna port information, and through a second antenna arrangement based on the second antenna port information.

According to a sixth aspect there is provided a non-transitory computer readable medium comprising program instructions for causing an apparatus to perform at least the following: receive, from a network element, downlink control information for scheduling a physical uplink shared channel transmission, determine whether the received downlink control information comprises first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, wherein, if it is determined that the received downlink control information comprises the first antenna port information and the second antenna port information, then the apparatus is further caused to perform the scheduled physical uplink shared channel transmission through a first antenna arrangement of the apparatus based on the first antenna port information, and through a second antenna arrangement of the apparatus based on the second antenna port information.

According to a seventh aspect there is provided a non-transitory computer readable medium comprising program instructions stored thereon for performing at least the following: receiving, from a network element, downlink control information for scheduling a physical uplink shared channel transmission, determining whether the received downlink control information comprises first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, wherein, if it is determined that the received downlink control information comprises the first antenna port information and the second antenna port information, then the non-transitory computer readable medium further comprises instructions stored thereon for performing the scheduled physical uplink shared channel transmission through a first antenna arrangement based on the first antenna port information, and through a second antenna arrangement based on the second antenna port information.

According to an eighth aspect there is provided a computer readable medium comprising program instructions stored thereon for performing at least the following: receiving, from a network element, downlink control information for scheduling a physical uplink shared channel transmission, determining whether the received downlink control information comprises first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, wherein, if it is determined that the received downlink control information comprises the first antenna port information and the second antenna port information, then the computer readable medium further comprises instructions stored thereon for performing the scheduled physical uplink shared channel transmission through a first antenna arrangement based on the first antenna port information, and through a second antenna arrangement based on the second antenna port information. According to a ninth aspect there is provided an apparatus comprising means for: transmitting, to a terminal device, downlink control information for scheduling a physical uplink shared channel transmission, wherein the transmitted downlink control information comprises at least one of first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, and means for receiving the scheduled downlink physical shared channel transmission, wherein, if the transmitted downlink control information comprises the first antenna port information and the second antenna port information, then the means are configured to receive the scheduled downlink physical shared channel transmission through a first antenna arrangement of the terminal device based on the first antenna port information, and through a second antenna arrangement of the terminal device based on the second antenna port information.

In some example embodiments according to the ninth aspect, the means comprises at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, to cause the performance of the apparatus.

According to a tenth aspect there is provided an apparatus comprising at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, to cause the apparatus at least to: transmit, to a terminal device, downlink control information for scheduling a physical uplink shared channel transmission, wherein the transmitted downlink control information comprises at least one of first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, and wherein, if the transmitted downlink control information comprises the first antenna port information and the second antenna port information, then the apparatus is further caused to receive the scheduled uplink physical shared channel transmission through a first antenna arrangement of the terminal device based on the first antenna port information, and through a second antenna arrangement of the terminal device based on the second antenna port information.

According to an eleventh aspect there is provided a method comprising: transmitting, to a terminal device, downlink control information for scheduling a physical uplink shared channel transmission, wherein the transmitted downlink control information comprises at least one of first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, and wherein, if the transmitted downlink control information comprises the first antenna port information and the second antenna port information, then the method further comprises receiving the scheduled downlink physical shared channel transmission through a first antenna arrangement of the terminal device based on the first antenna port information, and through a second antenna arrangement of the terminal device based on the second antenna port information.

According to a twelfth aspect there is provided a computer program comprising instructions for causing an apparatus to perform at least the following: transmit, to a terminal device, downlink control information for scheduling a physical uplink shared channel transmission, wherein the transmitted downlink control information comprises at least one of first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, and wherein, if the transmitted downlink control information comprises the first antenna port information and the second antenna port information, then the apparatus is further caused to receive the scheduled uplink physical shared channel transmission through a first antenna arrangement of the terminal device based on the first antenna port information, and through a second antenna arrangement of the terminal device based on the second antenna port information.

According to a thirteenth aspect there is provided a computer program comprising instructions stored thereon for performing at least the following: transmitting, to a terminal device, downlink control information for scheduling a physical uplink shared channel transmission, wherein the transmitted downlink control information comprises at least one of first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, and wherein, if the transmitted downlink control information comprises the first antenna port information and the second antenna port information, then the computer program further comprises instructions stored thereon for receiving the scheduled downlink physical shared channel transmission through a first antenna arrangement of the terminal device based on the first antenna port information, and through a second antenna arrangement of the terminal device based on the second antenna port information.

According to a fourteenth aspect there is provided a non-transitory computer readable medium comprising program instructions for causing an apparatus to perform at least the following: transmit, to a terminal device, downlink control information for scheduling a physical uplink shared channel transmission, wherein the transmitted downlink control information comprises at least one of first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, and wherein, if the transmitted downlink control information comprises the first antenna port information and the second antenna port information, then the apparatus is further caused to receive the scheduled uplink physical shared channel transmission through a first antenna arrangement of the terminal device based on the first antenna port information, and through a second antenna arrangement of the terminal device based on the second antenna port information.

According to a fifteenth aspect there is provided a non-transitory computer readable medium comprising program instructions stored thereon for performing at least the following: transmitting, to a terminal device, downlink control information for scheduling a physical uplink shared channel transmission, wherein the transmitted downlink control information comprises at least one of first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, and wherein, if the transmitted downlink control information comprises the first antenna port information and the second antenna port information, then the non-transitory computer readable medium further comprises instructions stored thereon for receiving the scheduled downlink physical shared channel transmission through a first antenna arrangement of the terminal device based on the first antenna port information, and through a second antenna arrangement of the terminal device based on the second antenna port information.

According to a sixteenth aspect there is provided a computer readable medium comprising program instructions stored thereon for performing at least the following: transmitting, to a terminal device, downlink control information for scheduling a physical uplink shared channel transmission, wherein the transmitted downlink control information comprises at least one of first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, and wherein, if the transmitted downlink control information comprises the first antenna port information and the second antenna port information, then the computer readable medium further comprises instructions stored thereon for receiving the scheduled downlink physical shared channel transmission through a first antenna arrangement of the terminal device based on the first antenna port information, and through a second antenna arrangement of the terminal device based on the second antenna port information.

List of Drawings

In the following, the invention will be described in greater detail with reference to the embodiments and the accompanying drawings, in which

FIG. 1 illustrates an exemplary embodiment of a radio access network.

FIG. 2 illustrates an example embodiment of receiving downlink control information.

FIG. 3 illustrates an example embodiment of using a codeword to indicate combinations of transmission layers.

FIG. 4A and 4B illustrate example embodiment of mapping transmission layers and antenna ports.

FIG. 5 illustrates a flow chart according to an example embodiment. FIG. 6 and 7 illustrate example embodiments of an apparatus.

Description of Embodiments

The following embodiments are exemplifying. Although the specification may refer to "an", "one", or "some" embodiment^) in several locations of the text, this does not necessarily mean that each reference is made to the same embodiment(s), or that a particular feature only applies to a single embodiment. Single features of different embodiments may also be combined to provide other embodiments. Also, as used herein, "at least one of the following: <a list of two or more elements>" and similar wording, where the list of two or more elements are joined by "and" or "or", mean at least any of the elements, or at least any two or more of the elements, or at least all the elements.

As used in this application, the term 'circuitry' refers to all of the following: (a) hardware-only circuit implementations, such as implementations in only analog and/or digital circuitry, and (b) combinations of circuits and software (and/or firmware), such as (as applicable): (i) a combination of processor(s) or (ii) portions of processor(s)/software including digital signal processor(s), software, and memory(ies) that work together to cause an apparatus to perform various functions, and (c) circuits, such as a microprocessor(s) or a portion of a microprocessor(s), that require software or firmware for operation, even if the software or firmware is not physically present. This definition of 'circuitry' applies to all uses of this term in this application. As a further example, as used in this application, the term 'circuitry' would also cover an implementation of merely a processor (or multiple processors) or a portion of a processor and its (or their) accompanying software and/or firmware. The term 'circuitry' would also cover, for example and if applicable to the particular element, a baseband integrated circuit or applications processor integrated circuit for a mobile phone or a similar integrated circuit in a server, a cellular network device, or another network device. The above-described embodiments of the circuitry may also be considered as embodiments that provide means for carrying out the embodiments of the methods or processes described in this document.

The techniques and methods described herein may be implemented by various means. For example, these techniques may be implemented in hardware (one or more devices), firmware (one or more devices), software (one or more modules), or combinations thereof. For a hardware implementation, the apparatus (es) of embodiments may be implemented within one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), graphics processing units (GPUs), processors, controllers, microcontrollers, microprocessors, other electronic units designed to perform the functions described herein, or a combination thereof. For firmware or software, the implementation can be carried out through modules of at least one chipset (e.g. procedures, functions, and so on) that perform the functions described herein. The software codes may be stored in a memory unit and executed by processors. The memory unit may be implemented within the processor or externally to the processor. In the latter case, it can be communicatively coupled to the processor via any suitable means. Additionally, the components of the systems described herein may be rearranged and/or complemented by additional components in order to facilitate the achievements of the various aspects, etc., described with regard thereto, and they are not limited to the precise configurations set forth in the given figures, as will be appreciated by one skilled in the art.

Embodiments described herein may be implemented in a communication system, such as in at least one of the following: Global System for Mobile Communications (GSM) or any other second generation cellular communication system, Universal Mobile Telecommunication System (UMTS, 3G) based on basic wideband-code division multiple access (W-CDMA), high-speed packet access (HSPA), Long Term Evolution (LTE), LTE-Advanced, a system based on IEEE 802.11 specifications, a system based on IEEE 802.15 specifications, and/or a fifth generation (5G), as well as 5G-Advanced (i.e. 3GPP NR Rel-18 and beyond), mobile or cellular communication system. Also, the embodiments described herein may be implemented in a 6G communication system as well. The embodiments are not, however, restricted to the system given as an example but a person skilled in the art may apply the solution to other communication systems provided with necessary properties.

FIG. 1 depicts examples of simplified system architectures showing some elements and functional entities, all being logical units, whose implementation may differ from what is shown. The connections shown in FIG. 1 are logical connections; the actual physical connections may be different. It is apparent to a person skilled in the art that the system may comprise also other functions and structures than those shown in FIG. 1. The example of FIG. 1 shows a part of an exemplifying radio access network.

FIG. 1 shows terminal devices 100 and 102 configured to be in a wireless connection on one or more communication channels in a cell with an access node (such as (e/g)NodeB) 104 providing the cell. The access node 104 may also be referred to as a node. The wireless link from a terminal device to a (e/g)NodeB is called uplink or reverse link and the wireless link from the (e /g) NodeB to the terminal device is called downlink or forward link. It should be appreciated that (e/g)NodeBs or their functionalities may be implemented by using any node, host, server or access point etc. entity suitable for such a usage. It is to be noted that although one cell is discussed in this exemplary embodiment, for the sake of simplicity of explanation, multiple cells may be provided by one access node in some exemplary embodiments.

A communication system may comprise more than one (e/g)NodeB in which case the (e/g)NodeBs may also be configured to communicate with one another over links, wired or wireless, designed for the purpose. These links may be used for signalling purposes. The (e/g)NodeB is a computing device configured to control the radio resources of communication system it is coupled to. The (e/g)NodeB may also be referred to as a base station, an access point or any other type of interfacing device including a relay station capable of operating in a wireless environment. The (e/g)NodeB includes or is coupled to transceivers. From the transceivers of the (e/g)NodeB, a connection is provided to an antenna unit that establishes bidirectional radio links to user devices. The antenna unit may comprise a plurality of antennas or antenna elements. The (e/g)NodeB is further connected to core network 110 (CN or next generation core NGC). Depending on the system, the counterpart on the CN side may be a serving gateway (S-GW, routing and forwarding user data packets), packet data network gateway (P-GW), for providing connectivity of terminal devices (UEs) to external packet data networks, or mobile management entity (MME), etc. The terminal device (also called UE, user equipment, user terminal, user device, etc.) illustrates one type of an apparatus to which resources on the air interface are allocated and assigned, and thus any feature described herein with a terminal device may be implemented with a corresponding apparatus, such as a relay node. An example of such a relay node is a layer 3 relay (self-backhauling relay) towards the base station. Another example of such a relay node is a layer 2 relay. Such a relay node may contain a terminal device part and a Distributed Unit (DU) part. A CU (centralized unit) may coordinate the DU operation via F1AP -interface for example.

The terminal device may refer to a portable computing device that includes wireless mobile communication devices operating with or without a subscriber identification module (SIM), or an embedded SIM, eSIM, including, but not limited to, the following types of devices: a mobile station (mobile phone), smartphone, personal digital assistant (PDA), handset, device using a wireless modem (alarm or measurement device, etc.), laptop and/or touch screen computer, tablet, game console, notebook, and multimedia device. It should be appreciated that a user device may also be an exclusive or a nearly exclusive uplink only device, of which an example is a camera or video camera loading images or video clips to a network. A terminal device may also be a device having capability to operate in Internet of Things (loT) network which is a scenario in which objects are provided with the ability to transfer data over a network without requiring human-to-human or human-to-computer interaction. The terminal device may also utilise cloud. In some applications, a terminal device may comprise a small portable device with radio parts (such as a watch, earphones or eyeglasses) and the computation is carried out in the cloud. The terminal device (or in some embodiments a layer 3 relay node) is configured to perform one or more of user equipment functionalities.

Various techniques described herein may also be applied to a cyber-physical system (CPS) (a system of collaborating computational elements controlling physical entities). CPS may enable the implementation and exploitation of massive amounts of interconnected ICT devices (sensors, actuators, processors microcontrollers, etc.) embedded in physical objects at different locations. Mobile cyber physical systems, in which the physical system in question has inherent mobility, are a subcategory of cyber-physical systems. Examples of mobile physical systems include mobile robotics and electronics transported by humans or animals.

Additionally, although the apparatuses have been depicted as single entities, different units, processors and/or memory units (not all shown in FIG. 1) may be implemented.

5G enables using multiple input - multiple output (M1M0) antennas, many more base stations or nodes than the LTE (a so-called small cell concept), including macro sites operating in co-operation with smaller stations and employing a variety of radio technologies depending on service needs, use cases and/or spectrum available. 5G mobile communications supports a wide range of use cases and related applications including video streaming, augmented reality, different ways of data sharing and various forms of machine type applications such as (massive) machine-type communications (mMTC), including vehicular safety, different sensors and real-time control. 5G is expected to have multiple radio interfaces, namely below 6GHz, cmWave and mmWave, and also being integratable with existing legacy radio access technologies, such as the LTE. Integration with the LTE may be implemented, at least in the early phase, as a system, where macro coverage is provided by the LTE and 5G radio interface access comes from small cells by aggregation to the LTE. In other words, 5G is planned to support both inter-RAT operability (such as LTE-5G) and inter-Rl operability (inter-radio interface operability, such as below 6GHz - cmWave, below 6GHz - cmWave - mmWave). One of the concepts considered to be used in 5G networks is network slicing in which multiple independent and dedicated virtual sub-networks (network instances) may be created within the same infrastructure to run services that have different requirements on latency, reliability, throughput and mobility. The current architecture in LTE networks is fully distributed in the radio and fully centralized in the core network. The low latency applications and services in 5G may require bringing the content close to the radio which may lead to local break out and multi-access edge computing (MEC). 5G enables analytics and knowledge generation to occur at the source of the data. This approach requires leveraging resources that may not be continuously connected to a network such as laptops, smartphones, tablets and sensors. MEC provides a distributed computing environment for application and service hosting. It also has the ability to store and process content in close proximity to cellular subscribers for faster response time. Edge computing covers a wide range of technologies such as wireless sensor networks, mobile data acquisition, mobile signature analysis, cooperative distributed peer-to-peer ad hoc networking and processing also classifiable as local cloud/fog computing and grid/mesh computing, dew computing, mobile edge computing, cloudlet, distributed data storage and retrieval, autonomic self-healing networks, remote cloud services, augmented and virtual reality, data caching, Internet of Things (massive connectivity and/or latency critical), critical communications (autonomous vehicles, traffic safety, real-time analytics, time-critical control, healthcare applications).

The communication system is also able to communicate with other networks, such as a public switched telephone network or the Internet 112, and/or utilise services provided by them. The communication network may also be able to support the usage of cloud services, for example at least part of core network operations may be carried out as a cloud service (this is depicted in FIG. 1 by "cloud" 114). The communication system may also comprise a central control entity, or a like, providing facilities for networks of different operators to cooperate for example in spectrum sharing.

Edge cloud may be brought into radio access network (RAN) by utilizing network function virtualization (NFV) and software defined networking (SDN). Using edge cloud may mean access node operations to be carried out, at least partly, in a server, host or node operationally coupled to a remote radio head or base station comprising radio parts. It is also possible that node operations will be distributed among a plurality of servers, nodes or hosts. Application of cloudRAN architecture enables RAN real time functions being carried out at the RAN side (in a distributed unit, DU 104) and non-real time functions being carried out in a centralized manner (in a centralized unit, CU 108).

It should also be understood that the distribution of labour between core network operations and base station operations may differ from that of the LTE or even be non-existent. Some other technology that may be used includes for example Big Data and all-IP, which may change the way networks are being constructed and managed. 5G (or new radio, NR) networks are being designed to support multiple hierarchies, where MEC servers can be placed between the core and the base station or nodeB (gNB). It should be appreciated that MEC can be applied in 4G networks as well.

5G may also utilize satellite communication to enhance or complement the coverage of 5G service, for example by providing backhauling or service availability in areas that do not have terrestrial coverage. Satellite communication may utilise geostationary earth orbit (GEO) satellite systems, but also low earth orbit (LEO) satellite systems, for example, mega-constellations. A satellite 106 comprised in a constellation may carry a gNB, or at least part of the gNB, that create on-ground cells. Alternatively, a satellite 106 may be used to relay signals of one or more cells to the Earth. The on-ground cells may be created through an on-ground relay node 104 or by a gNB located on-ground or in a satellite or part of the gNB may be on a satellite, the DU for example, and part of the gNB may be on the ground, the CU for example. Additionally, or alternatively, high-altitude platform station, HAPS, systems may be utilized.

It is to be noted that the depicted system is an example of a part of a radio access system and the system may comprise a plurality of (e/g)NodeBs, the terminal device may have an access to a plurality of radio cells and the system may comprise also other apparatuses, such as physical layer relay nodes or other network elements, etc. At least one of the (e/g)NodeBs may be a Home(e/g)nodeB. Additionally, in a geographical area of a radio communication system a plurality of different kinds of radio cells as well as a plurality of radio cells may be provided. Radio cells may be macro cells (or umbrella cells) which are large cells, usually having a diameter of up to tens of kilometers, or smaller cells such as micro-, femto- or picocells. The (e/g)NodeBs of FIG. 1 may provide any kind of these cells. A cellular radio system may be implemented as a multilayer network including several kinds of cells. In some exemplary embodiments, in multilayer networks, one access node provides one kind of a cell or cells, and thus a plurality of (e/g)NodeBs are required to provide such a network structure.

For fulfilling the need for improving the deployment and performance of communication systems, the concept of "plug-and-play" (e/g)NodeBs has been introduced. A network which is able to use "plug-and-play" (e/g)NodeBs, may include, in addition to Home (e/g)NodeBs (H(e/g)nodeBs), a home node B gateway, or HNB-GW (not shown in FIG. 1). A HNB Gateway (HNB-GW), which may be installed within an operator’s network may aggregate traffic from a large number of HNBs back to a core network.

When multiple transmission-reception-points (M-TRP) are utilized, for example in Rel-17 of a 3GPP specification, for uplink transmission, a network that comprises a terminal device performing uplink transmission using the M-TRP, may provide to the terminal device a downlink control information (DCI ) , which may be a single DC1 (S- DCI ) for time-division multiplexing (TDM) for M-TRP physical uplink shared channel (PUSCH) repetition and for selection of an antenna arrangement. An antenna arrangement comprised in a terminal device may be understood as one of the following: an antenna panel, a spatial filter, a logical entity for transmitting signals, a set of antenna elements, a transmission beam or any combination thereof. The terminal device may comprise one or more antenna arrangements and the network may be aware of those antenna arrangements for example based on capability set index reporting. The capability index set reporting may comprise, for example, information regarding the number of antenna ports associated with uplink sound reference signal (UL SRS) for codebook based transmission into a certain spatial UL direction associated with reported DL reference signal/signal (i.e. NZP-CS1-RS or SSB). Based on the availability of such information, the network may thus trigger transmission of two different UL SRS resource sets with the usage of codebook to perform TRP-specific transmit precoder matrix indicator (TPMI) hypotheses for an antenna arrangement associated with the PUSCH transmissions. In other words, the network may determine precoder index and rank selection for an antenna arrangement that is to be used for the PUSCH transmission. It is to be noted that determining performed by the network may be understood as a determination by a network entity such as a base station, or any other suitable one or more network element comprised in the network. Further, also TRPs comprised in the network may be understood to be network elements.

FIG. 2 illustrates an example embodiment of a terminal device 200 receiving an S- DC1, such as a Rel-17 S-DC1, for TDM based M-TRP PUSCH with and without repetition and for selecting an antenna arrangement between two TRPs. In this example embodiment the terminal device 200 comprises a first antenna arrangement 202 and a second antenna arrangement 204. The network comprises in this example embodiment the TRPs 210 and 220. The TRP 210 provides a beam grid 215 and the TRP 220 provides the beam grid 225. In this example embodiment there are two different UL SRS resource sets configured with two different downlink (DL), or joint DL and UL/UL transmission configuration indicator (TCI ) states associated as spatial sources. Additionally, these two different UL SRS resource sets can be also configured with followUnifiedTC!StateSRS-R17 information enabling dynamic spatial information update based on indicated TCI states. The network may thus trigger a PUSCH transmission by indicating, using an S-DC1 230, that the TRP 220 may transmit to the terminal device 200, a codepoint for a single SRS resource set indicator, in which 2-bits, and thereby 4 values, are reserved, when two SRS resource sets configured with usage codebook or non-codebook, and otherwise O-bit. The codepoint, which may be referred to as a DC1 codepoint, is included in the S-DC1 230 in this example embodiment. In this example embodiment, the first value out of the four possible values of the DC1 codepoint may be used to indicate which of the two SRS resource indicators (SRI)s, the first or the second, is used to enable dynamic switching between a single TRP (either 210 or either 220) PUSCH transmission in time division multiplexing (TDM) manner and the other remaining two bits may be used to enable multi-TRP PUSCH transmission between TRP 210 and TRP 220 in TDM manner with repetition. Further, in this example embodiment, either cyclical or sequential mapping may be configured via RRC for mapping two SRI to PUSCH repetitions. Moreover, for codebook based transmission, the DC1 includes, in this example embodiment, two separate codepoint fields for SRls and two precoding information and number of transmission layers fields. It is worth noting that the first field indicates the number of transmission layers, whereas the second field does not. For non-codebook based transmission, the DC1 may comprise two SRI codepoint fields, where the first one indicates the transmission layers and second does not. Based on the received S-DC1 230, the terminal device may then transmit the PUSCH transmission 232 using the antenna arrangement 204 and the PUSCH transmission 234 using the antenna arrangement 202. In this example embodiment, though, the PUSCH transmissions 232 and 234 are not simultaneous transmissions, via the multiple antenna arrangements 202 and 204.

In short-range related use cases such as home entertainment, video surveillance, in industrial or healthcare related use cases, in which devices and their usage of power, their cost and/or form factor may not be as stringent as when a terminal device is to be handheld and mobile, a higher peak data rate may be desirable to allow such use cases in a useful manner. In such use cases, it may be desirable to have for example UL transmission with more than 4 transmission antenna arrangements to bridge a gap between the DL and UL spectral efficiency in frequency range (FR) 1 and FR2 related use case. Thus, it may be beneficial to have for example two antenna arrangements performing simultaneous UL transmissions to obtain higher UL throughput and/or reliability with M-TRP. When an UL transmission is performed using spatial division multiplexing (SDM}, there may be a plurality of transmission layers used for the transmission. The plurality of transmission layers may be combined in various manners. For example, there may be the following combinations of transmission layers: {1+1, 1+2, 2+1, 2+2}. To indicate the combinations of the transmission layers, a single codeword may be used as illustrated in FIG. 3. In FIG. 3 there is a codeword 310. The codeword 310 provides a codeword-to- transmission layer mapping 320, which then may provide, for a first antenna arrangement, the indication 330 and for the second antenna arrangement the indication 335. The indication 330 may provide sounding reference signal indicator (SRI} and transmission precoder matrix indicator (TPM1} to indicate the antenna ports of the first antenna arrangement as well as associated TPM1 that are to be used for the transmission. Thus, the indication 330 may provide SRI#j and TPMl#x. Correspondingly, the indication 335 may provide SRI#m and TPMl#y to indicate the antenna ports of the second antenna arrangement as well as associated TPM1 that are to be used for the transmission. The codeword 310 in this example embodiment is thus a single codeword for indicating the transmission layer combinations for an SDM transmission.

To further enhance PUSCH transmissions, it may be beneficial to allow dynamic switching between transmission performed by the terminal device using a single antenna arrangement and transmission performed by the terminal device using multiple antenna arrangements, and vice versa. Such switching may be applicable for example to SDM transmissions with at least one codeword such as the codeword 310. Also, in such switching, the different transmission layer combinations may be associated with the different antenna arrangements in dynamic manner. Further, the PUSCH transmission may be transmitted using one or more TRPs and the switching may be indicated using a single DC1.

In an example embodiment, uplink demodulation reference signal (UL DMRS} indication scheme that is for indicating antenna ports for SDM based codebook, and also non-codebook, PUSCH transmission using multiple antenna arrangements simultaneously may be defined using a DC1. In this example embodiment, the PUSCH transmission is an SDM based codebook PUSCH transmission and the DC1 in this example embodiment enables dynamic switching from transmitting using, by a terminal device, a single antenna arrangement to transmitting using, simultaneously multiple antenna arrangements with different transmission layer combinations, by the terminal device, and vice versa. In this example embodiment, simultaneous PUSCH transmission via multiple antenna arrangements may be indicated by extending value range of existing DC1 codepoint field for SRS resource set indication, e.g. by one or two bits or introducing new DC1 codepoint field for indicating simultaneous PUSCH transmission via multiple antenna arrangements.

In this example embodiment, the DC1, that the terminal device receives from a network element, indicates a one-to-one mapping between one or more UL DMRS antenna ports of the terminal device and precoder information indicated using the DC1. The DC1 may indicate the mapping implicitly or explicitly. The mapping between the one or more UL DMRS antenna ports and the precoder information may be understood to comprise a mapping between TPM1 and uplink transmission layers, subjected to a number of SRS antenna ports (APs) and uplink full-power transmission modes, such as fullPowerModel or fullPowerMode2. Thus, the DC1 may be a DC1 for PUSCH transmission using simultaneously multiple antenna arrangements.

If the DC1 comprises a first precoding information (Pl-1) and a second precoding information (Pl-2), as well as a first antenna port information (API-1) and a second antenna port information (API-2), then the Pl-1 may be for defining one or more first transmission layers that are associated with the API-1. In other words, the Pl-1 may define the one or more first transmission layers related to the API-1, and the one or more first transmission layers associated with the API-1 maybe understood as a first set of UL DMRS APs. Correspondingly, the Pl-2 may be for defining one or more second transmission layers associated with the API-2. In other words, the one or more second UL DMRS APs. It is worth noting that Pl-1 and PI-2 indicate independently the transmission layers associated with the first and second antenna arrangements, respectively. Thus, the terminal device receives, from the network element, a DC1 for scheduling a codebook based PUSCH transmission and determines if the received DC1 comprises API-1 for the one or more first transmission layers associated with, in other words related to, the PUSCH transmission, and API-2 for the one or more second transmission layers associated with, in other words related to, the PUSCH transmission.

Optionally, it may be assumed, by the terminal device, that the one or more first transmission layers are to be prioritized with respect to the one or more second transmission layers. For example, Pl-1 may comprise information regarding two transmission layers, such as TPMl-x, x=0, .., K, with v¹o,v¹i, where v¹o,v¹i are precoding vectors for rank 2 transmission associated with TPMl-x. PI-2 may then comprise information regarding one transmission layer, such as TPMl-y with v²o where v²o is precoding vector for rank 1 transmission associated with TPMl-y. Then the first transmission layers v'o and vh are associated with respective UL DMRS antenna ports p_x and p_y, in other words, v'o

p_y , where UL DMRS antenna port p_x and p_y are indicated via the API-1, and the second transmission layers is associated with UL DMRS antenna port p_z, (i.e. v²o

p_z), where UL DMRS antenna port, p_z is indicated via the API-2. Thus, in this example embodiment, API may be understood as an index for indicating a different number of DMRS code division multiplexing (CDM) groups, different DMRS antenna port combinations and a different number of front-loaded DMRS symbols. Pl, in this example embodiment, may be understood as an index for indicating the different number of transmission layers, and different TPMls.

In this example embodiment, the API-1 and API-2, which is applicable to both type-1 and type-2 DMRS, are associated with the first UL SRS resource information, which indicates a first set of SRls (i.e. one or more SRI where SRI is associated with SRS resource), and the second UL SRS resource, which indicates a second of set SRls (i.e. one or more SRI where SRI is associated with SRS resource), the indicated DMRS antenna port value(s) define one-to-one mapping between the indicated UL DMRS antenna ports and PUSCH transmission layer (s) associated with first and second set of indicated SRIs and the first and second set of transmission antenna arrangements comprised in the terminal device. Also, the terminal device may determine the number of front-loaded DMRS symbols by summing up the number of front-loaded DMRS symbols associated with the API-1 and API-2 while taking into account the indicated number of CDM groups associated with AP-1 and API-2, respectively.

In this example embodiment, if the DC1 defines a single one of the (PI-1, API-1) pair and (Pl-2, API-2) pair, then the terminal device determines that it is to switch from transmitting the SDM PUSCH transmission using both antenna arrangements simultaneously, to using a single antenna arrangement for the transmission with the transmission layer information indicated by the single (Pl, API) pair. For example, if Pl-1 and AP-1 is determined to be equal to a pre-determined value, such as zero or an empty field, and if it is determined that Pl-2 indicates two layers, for example TPMI with v²o,v²i, and API-2 indicates antenna ports, for example antenna ports 2 and 3, the terminal device may in response switch to transmit the PUSCH transmission from simultaneously transmitting using two antenna arrangements to transmitting the PUSCH transmission using a single antenna arrangement with Pl-2 transmission layer information via UL DMRS antenna ports 2 and 3 associated with antenna associated with the second SRI. It is to be noted that if the two antenna arrangements are to be used for the PUSCH transmission, then the single (Pl, API) pair is not equal to the pre-determined value and also, both pairs are defined.

In another example embodiment, the PUSCH transmission is an SDM based noncodebook PUSCH transmission. In this example embodiment as well, the DC1 enables dynamic switching from transmitting using, by a terminal device, a single antenna arrangement to transmitting using, simultaneously multiple antenna arrangements with different transmission layer combinations, by the terminal device, and vice versa. In this example embodiment, the DC1, which may be a single DC1, that the terminal device receives from a network element, indicates a one-to-one mapping between one or more UL DMRS antenna ports of the terminal device and UL SRS resource information. In this example embodiment, DCI may define an SRI-1 and an SRI-2 codepoints. The DCI may also define API-1 and API-2 codepoint fields as in the previous example embodiment. In this example embodiment, the SRI-1 indicates one or more SRls and defines one or more first transmission layers that are associated with the API-1, in other words, a first set of DMRS APs, and the SRI-2 indicates one or more SRI and defines one or more second transmission layers that are associated with second antenna port information, in other words, a second set of DMRS APs. In this example embodiment, the terminal device may, optionally, assume that the one or more first transmission layers are to be prioritized in view of the one or more second transmission layers.

In this example embodiment, the API-1 and the API-2, which are applicable to both the type-1 and type-2 DMRS, are associated with the first UL SRS resource information, which includes a first set of SRls, and a second UL SRS resource information, which includes a second set of SRls, the indicated DMRS antenna port values (s) define one-to-one mapping between the indicated UL DMRS antenna ports and PUSCH transmission layer(s) associated with the first and second set of indicated SRls and the first and second set of antenna arrangements comprised in the terminal device, respectively.

As in the previous example embodiment, if the terminal device then determines that one of the pairs, (SRI-1, API-1) or (SRI-2, API-2) is not defined in the received DCI, the terminal device may then, based on or as a response, switch from transmitting the PUSCH transmission using two antenna arrangements for transmitting, simultaneously, to using a single antenna arrangement for the transmission of the PUSCH transmission with indicated transmission layer information and DMRS port information indicated by SRI and API. It is to be noted that in this example embodiment, API may be understood to be an indicator, such as an index, to indicate information regarding a different number of DMRS CDM groups, different DMRS antenna port combinations and the different number of front-loaded symbols. In this example embodiment, the SRI indicates information on the different number of SRls matching the number of transmission layers transmitted through the respective antenna arrangement.

FIG. 4A illustrates an example embodiment of a codebook based one-to-one mapping between PUSCH transmission layers and DMRS antenna ports using a DC1 for the PUSCH transmission transmitted, by a terminal device, using multiple antenna arrangements. In this example embodiment, the DC1 defines a first API 400 that indicates the first DMRS port(s), the first number of front-loaded symbols and the first number of CDM groups. As there may be more than one API defined in the DC1, the API 405 illustrates the n-th API. Correspondingly to the API 400, the API 405 indicates the n-th DMRS port(s), the n-th number of front-loaded symbols and the n- th number of CDM groups. The API 400 is then associated with the first PR1 410 and the first PR1410 indicates the first number of transmission layers and the first TPM1. It is to be noted that the number of layers may be understood as layer information, or it may be comprised in a layer information. Correspondingly, the API 405 is associated with the n-th PR1 415 that indicates the n-th number of transmission layers and the n-th TPM1. It is to be noted that a set of consecutive PRls and APIs, such as PR1-1, PR1-2, PR1-3 and API-1, API-2, API-3, may define a mapping order of PUSCH transmission layers with DMRS antenna ports. The total number of transmission layers may be equal to the sum of transmission layers indicated by the PRls, which is also equal to the sum of DMRS ports indicated by the APIs. The total number of front-loaded-symbols may be the sum of the front-loaded-symbols indicated by the APIs while taking into account indicated number of CDM groups associated with APIs.

Next, in FIG. 4A, there are SRI 420 and SRI 425 illustrated. The SRI 420 is the first SRI and the SRI 425 is the n-th SRI. The SRls then map to the transmission antenna arrangements of the terminal device, respectively. That is, to the first antenna arrangement 430 and to the n-th antenna arrangement 435.

FIG. 4B illustrates an example embodiment of a non-codebook based one-to-one mapping between PUSCH transmission layers and DMRS antenna ports using a DCI for the PUSCH transmission transmitted, by a terminal device, using multiple antenna arrangements. In this example embodiment, the DCI defines a first API 450 that indicates the first DMRS port(s), the first number of front-loaded symbols and the first number of CDM groups. As there may be more than one API defined in the DCI, the API 455 illustrates the n-th API. Correspondingly to the API 450, the API 455 indicates the n-th DMRS port(s), the n-th number of front-loaded symbols and the n- th number of CDM groups. The API 450 is then associated with SRI 460 and the SRI 460 indicates the first number of transmission layers. Correspondingly, the API 455 is associated with the n-th SRI 465 that indicates the n-th number of transmission layers. It is to be noted that the total number of transmission layers may be equal to the sum of transmission layers indicated by the SRls, which is also equal to the sum of DMRS ports indicated by the APIs. The total number of front-loaded-symbols may be the sum of the front-loaded-symbols indicated by the APIs while taking into account indicated number of CDM groups associated with APIs. The SRls then map to the transmission antenna arrangements of the terminal device, respectively. That is, to the first antenna arrangement 470 and to the n-th antenna arrangement 475.

In a further example embodiment of one-to-one antenna port indication, there may be two SRS resource sets configured with higher layer parameter usage in SRS- ResourceSet set to codebook. Then, for the one-to-one antenna port indication, two SRls, two TPMls, and two DMRS antenna ports may be defined in the DCI fields of two SRS resource indicators and two precoding information, and number of transmission layers and one or two APIs for DCI format 0_l or format 0_2. For the two TPMls, the transmission precoder may be selected from the uplink codebook that has a number of antenna ports equal to the higher layer parameter nrofSRS-Ports for the indicated SRls. For two DMRS antenna ports, the terminal device may determine a first set of Kl-DMRS antenna ports by ordering of DMRS antenna ports given by antenna port table associated with AP-1 and second set of K2-DMRS antenna ports by ordering of DMRS antenna ports given by antenna port table subjected to DMRS-type, maxLength, rank associated with AP-2 where the maxLength is determined by summing up maxLengths given by AP-1 + AP-2 while taking into account indicated number of CDM groups associated with APIs.

In general, a terminal device may receive, from a network element, downlink control information for scheduling a physical uplink shared channel transmission. Based on the received downlink control information, the terminal device may then determine if first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission are defined using the received downlink control information. If the terminal device determines that the received downlink control information comprises the first antenna port information and the second antenna port information, then the terminal device may perform the scheduled physical uplink shared channel transmission through a first antenna arrangement of the terminal device based on the first antenna port information, and through a second antenna arrangement of the terminal device based on the second antenna port information. On the other hand, if the terminal device determines that the received DC1 comprises a single one of the first antenna port information and the second antenna port information, or if it is determined that one of the first antenna port information and the second antenna port information in the received downlink control information is equal to a pre-determined value, then the terminal device may perform the scheduled physical uplink shared channel transmission through a single antenna arrangement of the terminal device. It is to be noted that the first and the second antenna port information may be independent of each other, in other words, they may be separately encoded and have independent values. It is also to be noted that transmission layers associated with the scheduled physical uplink shared channel transmission may also be understood as layers related to the scheduled physical uplink shared channel transmission. Also, transmitting the physical uplink shared channel transmission may be understood as transmitting the transmission layers. Thus, the terminal device may receive the DCI for scheduling a physical uplink shared channel transmission, and based on the DCI, perform the physical uplink shared channel transmission. In some examples, the DCI comprises first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission. Thus, based on the DCI comprising the first antenna port information and the second antenna port information, the terminal device performs the physical uplink shared channel transmission through a first antenna arrangement of the apparatus based on the first antenna port information, and through a second antenna arrangement of the apparatus based on the second antenna port information.

In some examples, the DCI comprises a single one of the first antenna port information and the second antenna port information (i.e. one of the first antenna port information and second antenna port information, but not the other one). Thus, based on the DCI comprising single one of the first antenna port information and the second antenna port information, the terminal device performs the scheduled physical uplink shared channel transmission through a single antenna arrangement of the terminal device. In an example, the terminal device determines that DCI comprises the first antenna port information but not the second antenna port information. Based on the determining, the terminal device may perform the scheduled physical uplink shared channel transmission through the first antenna arrangement, but not through the second antenna arrangement. In an example, the terminal device determines that DCI comprises the second antenna port information but not the first antenna port information. Based on the determining, the terminal device may perform the scheduled physical uplink shared channel transmission through the second antenna arrangement, but not through the first antenna arrangement. In some examples, one of the first antenna port information and the second antenna port information in the received DCI is equal to a pre-determined value. Based on one of the first antenna port information and the second antenna port information in the received DCI being equal to a pre-determined value, the terminal device performs the scheduled physical uplink shared channel transmission through a single antenna arrangement of the terminal device. For instance, based on the first antenna port information being equal to the pre-determined value, the terminal device may perform the physical uplink shared channel transmission through the second antenna arrangement, but not through the first antenna arrangement. For instance, based on the second antenna port information being equal to the pre-determined value, the terminal device may perform the physical uplink shared channel transmission through the first antenna arrangement, but not through the second antenna arrangement.

Also, in general, a network element such as a base station, transmit, to a terminal device, downlink control information for scheduling a physical uplink shared channel transmission, and the transmitted downlink control information may comprise at least one of first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission. If the transmitted downlink control information comprises the first antenna port information and the second antenna port information, then the base station may receive the scheduled uplink physical shared channel transmission through a first antenna arrangement of the terminal device based on the first antenna port information, and through a second antenna arrangement of the terminal device based on the second antenna port information. It is to be noted that the scheduled uplink physical shared channel transmission may be received through at least one TRP, and, additionally, or alternatively, the antenna arrangements of the terminal device may comprise spatial filters. If the transmitted downlink control information comprises a single one of the first antenna port information and the second antenna port information, or if one of the first antenna port information and the second antenna port information in the transmitted downlink control information is equal to a pre-determined value, then the apparatus is further caused to receive the scheduled physical uplink shared channel transmission through a single antenna arrangement of the terminal device.

In the example embodiments described above, dynamic UL DMRS antenna port indication schemes applicable for codebook and non-codebook based SDM simultaneous multi-panel PUSCH transmission may be enabled. The example embodiments described above may thus allow the dynamic switching from single antenna panel PUSCH transmission to simultaneous multi-panel transmission and vice versa with m-TRPs. Thus, the example embodiments described above may have benefits such as enabling, using first and second antenna port information, the network to dynamically switch from a single antenna arrangement transmission to simultaneous, multiple antenna arrangement PUSCH transmission and vice versa via S-DC1. Another benefit may be enabling usage of TRP-specific DMRS configuration indication to guarantee sufficient DMRS channel estimation quality at each TRP. It is to be noted that propagation conditions between different terminal devices and TRP pairs may vary thus leading to a need to modify DMRS parameters according to each terminal device and TRP link pair. Another additional benefit may be enabling enhanced scheduling flexibility to indicate different/additional DMRS antenna port combinations in the case of multi-user M1M0 transmission, for example, when compared with current DMRS antenna port combinations such as those defined in Rel-17 specification.

FIG. 5 illustrates a flow chart according to an example embodiment. It is noted that in the example one or two APIs are defined. However, solution herein is not limited to using two APIs, and thus it is possible that more than two APIs are indicated by the DC1. According to the example embodiment, in step 510, a DC1 for scheduling a PUSCH transmission. The DC1 is transmitted by a network element, such as a TRP or a base station and it is received by the terminal device. The terminal device then determines in step 520 if the DC1 comprises a first API and a second API. In other words, the terminal device determines if the DC1 defines a first API and a second API. The first API is for one or more first transmission layers associated with the scheduled PUSCH transmission, and the second API is for one or more second transmission layers associated with the scheduled PUSCH transmission.

If the terminal device determines that one of the first API or the second API is not defined, but the other one is, then the terminal device, in step 530, transmits the scheduled PUSCH transmission using a single antenna arrangement. The single antenna arrangement, which is comprised in the terminal device, corresponds to the API, the first or the second, that was defined.

Yet, if the terminal device determines that the first and the second API, then the terminal device, in step 525, determines if one of the first or the second API is equal to a pre-defined value, which may be considered as a dummy value as well. If one of the first or the second API comprises the pre-determined value, then, in step 530, the terminal device transmits the scheduled PUSCH transmission using a single antenna arrangement comprised in the terminal device and the single antenna arrangement corresponds to the API that was not equal to the pre-determined value.

If the terminal device determines in step 525 that neither of the first or the second API is equal to the pre-determined value, the terminal device, in step 535, transmits the scheduled PUSCH transmission through two antenna arrangements comprised in the terminal device. The transmission through the first antenna arrangement is based on the first API and the transmission through the second antenna arrangement is based on the second API. It is further noted that the actions of terminal device in blocks 520, 530 may or may not happen at the same time, and they should be understood as determination by the terminal device according to one or more rules (i.e. as defined in blocks 520, 530).

In this example embodiment, as the scheduled PUSCH transmission is transmitted by the terminal device, it may be transmitted using one or more antenna arrangements.

FIG. 6 illustrates an apparatus 600, which may be an apparatus such as, or comprised in, a terminal device, according to an example embodiment. The apparatus 600 comprises a processor 610. The processor 610 interprets computer program instructions and processes data. The processor 610 may comprise one or more programmable processors. The processor 610 may comprise programmable hardware with embedded firmware and may, alternatively or additionally, comprise one or more application specific integrated circuits, ASICs.

The processor 610 is coupled to a memory 620. The processor is configured to read and write data to and from the memory 620. The memory 620 may comprise one or more memory units. The memory units may be volatile or non-volatile. It is to be noted that in some example embodiments there may be one or more units of nonvolatile memory and one or more units of volatile memory or, alternatively, one or more units of non-volatile memory, or, alternatively, one or more units of volatile memory. Volatile memory may be for example RAM, DRAM or SDRAM. Non-volatile memory may be for example ROM, PROM, EEPROM, flash memory, optical storage or magnetic storage. In general, memories may be referred to as non-transitory computer readable media. The memory 620 stores computer readable instructions that are execute by the processor 610. For example, non-volatile memory stores the computer readable instructions and the processor 610 executes the instructions using volatile memory for temporary storage of data and/or instructions.

The computer readable instructions may have been pre-stored to the memory 620 or, alternatively or additionally, they may be received, by the apparatus, via electromagnetic carrier signal and/or may be copied from a physical entity such as computer program product. Execution of the computer readable instructions causes the apparatus 600 to perform functionality described above.

In the context of this document, a "memory" or "computer-readable media" may be any non-transitory media or means that can contain, store, communicate, propagate or transport the instructions for use by or in connection with an instruction execution system, apparatus, or device, such as a computer.

The apparatus 600 further comprises, or is connected to, an input unit 630. The input unit 630 comprises one or more interfaces for receiving a user input. The one or more interfaces may comprise for example one or more motion and/or orientation sensors, one or more cameras, one or more accelerometers, one or more microphones, one or more buttons and one or more touch detection units. Further, the input unit 630 may comprise an interface to which external devices may connect to.

The apparatus 600 also comprises an output unit 640. The output unit comprises or is connected to one or more displays capable of rendering visual content such as a light emitting diode, LED, display, a liquid crystal display, LCD and a liquid crystal on silicon, LCoS, display. The output unit 640 further comprises one or more audio outputs. The one or more audio outputs may be for example loudspeakers or a set of headphones.

The apparatus 600 may further comprise a connectivity unit 650. The connectivity unit 650 enables wired and/or wireless connectivity to external networks. The connectivity unit 650 may comprise one or more antennas and one or more receivers that may be integrated to the apparatus 600 or the apparatus 600 may be connected to. The connectivity unit 650 may comprise an integrated circuit or a set of integrated circuits that provide the wireless communication capability for the apparatus 600. Alternatively, the wireless connectivity may be a hardwired application specific integrated circuit, ASIC.

It is to be noted that the apparatus 600 may further comprise various component not illustrated in the FIG. 6. The various components may be hardware component and/or software components. The apparatus 700 of FIG. 7 illustrates an example embodiment of an apparatus that may be base station or be comprised in a base station, and that may embody the activator or the reader as described above. The apparatus may be, for example, a circuitry or a chipset applicable to an access node to realize the described embodiments. The apparatus 700 may be an electronic device comprising one or more electronic circuitries. The apparatus 700 may comprise a communication control circuitry 700 such as at least one processor, and at least one memory 720 including a computer program code (software) 722 wherein the at least one memory and the computer program code (software) 722 are configured, with the at least one processor, to cause the apparatus 700 to carry out any one of the example embodiments of the access node described above.

The memory 720 may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The memory may comprise a configuration database for storing configuration data. For example, the configuration database may store current neighbour cell list, and, in some example embodiments, structures of the frames used in the detected neighbour cells.

The apparatus 700 may further comprise a communication interface 730 comprising hardware and/or software for realizing communication connectivity according to one or more communication protocols. The communication interface 730 may provide the apparatus with radio communication capabilities to communicate in the cellular communication system. The communication interface may, for example, provide a radio interface to terminal devices. The apparatus 700 may further comprise another interface towards a core network such as the network coordinator apparatus and/or to the access nodes of the cellular communication system. The apparatus 700 may further comprise a scheduler 740 that is configured to allocate resources. Even though the invention has been described above with reference to example embodiments according to the accompanying drawings, it is clear that the invention is not restricted thereto but can be modified in several ways within the scope of the appended claims. Therefore, all words and expressions should be interpreted broadly and they are intended to illustrate, not to restrict, the embodiment. It will be obvious to a person skilled in the art that, as technology advances, the inventive concept can be implemented in various ways. Further, it is clear to a person skilled in the art that the described embodiments may, but are not required to, be combined with other embodiments in various ways.

Claims

1. An apparatus comprising at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to: receive, from a network element, downlink control information for scheduling a physical uplink shared channel transmission; determine whether the received downlink control information comprises first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, wherein, if it is determined that the received downlink control information comprises the first antenna port information and the second antenna port information, then the apparatus is further caused to perform the scheduled physical uplink shared channel transmission through a first antenna arrangement of the apparatus based on the first antenna port information, and through a second antenna arrangement of the apparatus based on the second antenna port information.

2. An apparatus according to claim 1, wherein, if it is determined that the received downlink control information comprises a single one of the first antenna port information and the second antenna port information, or if it is determined that one of the first antenna port information and the second antenna port information in the received downlink control information is equal to a pre-determined value, then the apparatus is further caused to perform the scheduled physical uplink shared channel transmission through a single antenna arrangement of the apparatus.

3. An apparatus according to claim 1 or 2, wherein the received downlink control information further comprises first precoding information for precoding the one or more first transmission layers, and second precoding information for precoding the one or more second transmission layers, and wherein the apparatus is further caused to perform the scheduled physical uplink shared channel transmission through the first antenna arrangement further based on the first precoding information, and through the second antenna arrangement further based on the second precoding information.

4. An apparatus according to any of claims 1 to 3, wherein the scheduled physical uplink shared channel transmission is performed simultaneously through the first and second antenna arrangements using spatial division multiplexing.

5. An apparatus according to any of claims 1 to 4, wherein the first and second antenna port information are separately encoded in the downlink control information.

6. An apparatus according to any of claims 1 to 5, wherein the first antenna port information indicates at least one of a number of demodulation reference signal code division multiplexing groups without data, one or more first demodulation reference signal antenna ports, and a number of front-loaded symbols, and wherein the second antenna port information indicates at least one of a number of demodulation reference signal code division multiplexing groups without data, one or more second demodulation reference signal antenna ports, and a number of front-loaded symbols.

7. An apparatus according to claim 3, wherein the first precoding information indicates one or more first sounding reference signal resource indicators, and the second precoding information indicates one or more second sounding reference signal resource indicators.

8. An apparatus according to claim 3, wherein the first precoding information indicates a first sounding reference signal resource indicator, a first transmit precoding matrix indicator and first layer information, and the second precoding information indicates a second sounding reference signal resource indicator, a second transmit precoding matrix indicator and second layer information

9. An apparatus comprising at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to: transmit, to a terminal device, downlink control information for scheduling a physical uplink shared channel transmission, wherein the transmitted downlink control information comprises at least one of first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, and wherein, if the transmitted downlink control information comprises the first antenna port information and the second antenna port information, then the apparatus is further caused to receive the scheduled uplink physical shared channel transmission through a first antenna arrangement of the terminal device based on the first antenna port information, and through a second antenna arrangement of the terminal device based on the second antenna port information.

10. An apparatus according to claim 9, wherein, if the transmitted downlink control information comprises a single one of the first antenna port information and the second antenna port information, or if one of the first antenna port information and the second antenna port information in the transmitted downlink control information is equal to a pre-determined value, then the apparatus is further caused to receive the scheduled physical uplink shared channel transmission through a single antenna arrangement of the terminal device.

11. An apparatus according to claim 9 or 10, wherein the scheduled physical uplink shared channel transmission is received simultaneously through the first and second antenna arrangements of the terminal device using spatial division multiplexing.

12. An apparatus according to any of claims 9 to 11, wherein the apparatus is further caused to separately encode the first and second antenna port information in the downlink control information.

13. An apparatus according to any of claims 9 to 12, wherein the first antenna port information indicates at least one of a number of demodulation reference signal code division multiplexing groups without data, one or more first demodulation reference signal antenna ports, and a number of front-loaded symbols; and wherein the second antenna port information indicates at least one of a number of demodulation reference signal code division multiplexing groups without data, one or more second demodulation reference signal antenna ports, and a number of front-loaded symbols.

14. A method comprising: receiving, from a network element, downlink control information for scheduling a physical uplink shared channel transmission; determining whether the received downlink control information comprises first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, wherein, if it is determined that the received downlink control information comprises the first antenna port information and the second antenna port information, then the method further comprises performing the scheduled physical uplink shared channel transmission through a first antenna arrangement based on the first antenna port information, and through a second antenna arrangement based on the second antenna port information.

15. A method comprising: transmitting, to a terminal device, downlink control information for scheduling a physical uplink shared channel transmission, wherein the transmitted downlink control information comprises at least one of first antenna port information for one or more first transmission layers associated with the scheduled physical uplink shared channel transmission, and second antenna port information for one or more second transmission layers associated with the scheduled physical uplink shared channel transmission, and wherein, if the transmitted downlink control information comprises the first antenna port information and the second antenna port information, then the method further comprises receiving the scheduled downlink physical shared channel transmission through a first antenna arrangement of the terminal device based on the first antenna port information, and through a second antenna arrangement of the terminal device based on the second antenna port information.