WO2021069646A1

WO2021069646A1 - Downlink aspects of contention free shared preconfigured uplink resources based on multi user multiple input multiple output

Info

Publication number: WO2021069646A1
Application number: PCT/EP2020/078382
Authority: WO
Inventors: Andreas HÖGLUND; Sandeep Narayanan KADAN VEEDU; Emre YAVUZ; Tuomas TIRRONEN; Gerardo Agni MEDINA ACOSTA
Original assignee: Telefonaktiebolaget Lm Ericsson (Publ)
Priority date: 2019-10-11
Filing date: 2020-10-09
Publication date: 2021-04-15
Also published as: EP4042624A1

Abstract

A method, system and apparatus for assessing downlink aspects of contention free shared preconfigured uplink resources (CFS-PUR) on multi-user multiple input multiple output (MU- MIMO) transmissions are disclosed. According to one aspect, a method in a network node includes simultaneously receiving a plurality of preconfigured uplink resource, PUR, uplink transmissions from a plurality of WDs using contention free shared PUR, CFS-PUR, and transmitting to the plurality of WDs in downlink transmissions that include multiplexed responses to the PUR uplink transmissions.

Description

DOWNLINK ASPECTS OF CONTENTION FREE SHARED PRECONFIGURED UPLINK RESOURCES BASED ON MULTI USER MULTIPLE INPUT MULTIPLE

OUTPUT

TECHNICAL FIELD

The present disclosure relates to wireless communications, and in particular, to downlink aspects of contention free shared preconfigured uplink resources (CFS-PUR) on multi-user multiple input multiple output (MU-MIMO) transmissions.

BACKGROUND

In Release 16 (Rel-16) of the Third Generation Partnership Project (3GPP) standards, two Work Items (WIs), one on “Additional machine type communications (MTC) enhancements for Long Term Evolution (LTE)” and one on “Additional enhancements for narrow band Internet of things (NB-IoT)” were considered, which have in common the following objective:

Improved uplink (UL) transmission efficiency and/or wireless device power consumption, which includes:

• Specifying support for transmission in preconfigured resources in idle and/or connected mode based on single carrier frequency division multiple access (SC-

FDMA) waveform for WDs with a valid timing advance [RAN 1 , RAN2, RAN4] : i) Both shared resources and dedicated resources can be discussed; ii) Note: This is limited to orthogonal (multi) access schemes.

During the 3GPP RANI #94bis meeting, three definitions that will apply for the transmissions on preconfigured uplink resources (PUR) were considered:

A dedicated preconfigured UL resource is defined as a physical uplink shared channel (PUSCH) resource used by a single wireless device (WD):

The PUSCH resource is time-frequency resource; and

Dedicated PUR is contention-free. A contention-free shared preconfigured UL resource (CFS PUR) is defined as an PUSCH resource simultaneously used by more than one WD:

PUSCH resource is at least a time-frequency resource; and

CFS PUR is contention-free.

Contention-based shared preconfigured UL resource (CBS PUR) is defined as an PUSCH resource simultaneously used by more than one WD:

PUSCH resource is at least time-frequency resource; and

CBS PUR is contention-based (CBS PUR may require contention resolution).

In 3GPP RANI #94bis, it was considered that “In idle mode, dedicated PUR is supported”, leaving for-further-study the support of shared PUR schemes, which according to the definitions applicable to this Work Item objective have been categorized as “CFS PUR” and “CBS PUR”.

To use PUR, the WD will access the network using legacy (i.e., existing) procedures and in connected-mode it will receive a “pre-configuration of uplink resources”, which it will use to transmit over the PUSCH the next time the wireless device in idle-mode.

The support of transmissions on pre-configured UL resources in IDLE mode is tied to the condition of being in possession of a valid timing advance (TA) and guaranteeing that the TA is still valid by the time the transmission on pre-configured UL resources is to be performed.

The UL transmissions over PUR make use of the Physical Uplink Shared Channel (PUSCH), which carries unicast user data and a Demodulation Reference Signals (DMRS) for channel estimation. In one slot there are seven symbols where one of them is used to carry DMRS and the rest are used to carry user data.

Upon a successful PUR transmission, the WD should receive an acknowledgement (ACK), which can be either a Ll-ACK or a L2/L3-ACK.

The base station (also referred to herein as a network node, eNodeB or gNB) will transmit a Ll-ACK only when it has received the data transmitted in the UL successfully and confirmed that there is no pending data in the downlink (DL) for that WD as Ll-ACK may provide battery savings by putting the WD back to sleep after its reception. On the other hand, L2/L3-ACK, i.e., a response in medium access control (MAC) or radio resource control (RRC) layer, provides integrity protection and can be used to perform PUR re-configurations and to deliver DL data to the WD.

For dedicated PUR, a few milliseconds after the end of UL transmission, the WD monitors the downlink control channel to receive either an L1ACK, an UL-Grant for re- transmission, or a DL-assignment for a RRC message (i.e., the L2/L3 ACK). As mentioned, if the transmission was successfully received by the network node, either an LI -ACK or an L2/L3-ACK should be received.

In the 3GPP RANI #98, the potential support of CFS-PUR has been captured as a Working Assumption in the following table

The above refers to resource allocations in the frequency domain of one physical resource block (PRB) (12 subcarriers of 15Khz each) for narrowband Internet of Things (NB- IoT), or one or more PRBs in the case of evolved machine type communications (eMTC). With contention free shared preconfigured uplink resources (CFS-PUR), two or more WDs may at some point transmit over exactly the same radio resources by overlapping their transmissions (e.g., WD1 and WD2 are scheduled by the network node to transmit simultaneously on the same Physical Resource Block).

The potential support of CFS-PUR may be based on MU-MIMO. The network node has to distinguish between the WDs that are transmitting simultaneously, and for that reason the DMRS sequences of those WDs should be orthogonal to each other. However, the data of the WDs that are transmitting simultaneously is not orthogonal, and for that reason CFS-PUR based on MU-MIMO has to operate at low signal to noise ratio (SNR) (SNR < OdB) as to avoid the WDs interfering too strongly with each other. If the WDs that are simultaneously transmitting using CFS-PUR based on MU-MIMO are recoverable, then the gain comes from the combined throughput.

The discussions in 3GPP have so far been focused on evaluating the potential gains of CFS-PUR based on MU-MIMO, and in RANI #98 a place holder for its potential support has been discussed. However, beyond the potential gains of CFS-PUR based on MU-MIMO what has not been discussed so far is what would be needed in terms of downlink (DL) for it to work. That is, the uplink (UL) transmissions with CFS-PUR based on MU-MIMO will be to some extent orthogonal but the DL transmissions are not and major design changes with respect to the framework that have been discussed for dedicated PUR might not be implemented.

For supporting CFS-PUR based on MU-MIMO, the downlink aspects also need to be functional. Thus, if CFS-PUR based on MU-MIMO is supported, the UL transmissions will be to some extent orthogonal at low SNR, but the DL transmissions are not and major design changes with respect to the framework that have been discussed for dedicated PUR might not be available for reuse.

CFS-PUR enables higher spectral efficiency and capacity since multiple WDs can be scheduled in the same physical resource. But unless there is a similar enhancement for the acknowledgements and/or scheduling re-transmissions, there will be little gained in practice. For example, if 4 WDs could share a CFS-PUR resource, it will take at least 4 consecutive subframes to acknowledge these transmissions (in good coverage). There cannot be a new CFS-PUR transmission until 5 subframes later, which severely limits the gain. This is because it may not be possible to perform DL transmissions and/or scheduling retransmissions simultaneously to a plurality of WDs.

SUMMARY

Some embodiments advantageously provide methods, network nodes and wireless devices for assessing downlink aspects of contention free shared preconfigured uplink resources (CFS-PUR) based on multi-user multiple input multiple output (MU-MIMO) transmissions.

Some embodiments enable contention free shared preconfigured uplink resources (CFS-PUR) based on multi-user multiple input multiple output (MU-MIMO) to be used to perform DL transmissions and/or scheduling retransmissions in an easy and signaling efficient way.

Some embodiments may include assessing downlink aspects of CFS-PUR based on MU-MIMO including, for example:

• Handling of acknowledgements for two or more WDs simultaneously transmitting using CFS-PUR based on MU-MIMO. The acknowledgements can be multiplexed in a collision free manner (e.g., using WD specific offsets) within the same search space window or using several search space windows. The ACKs multiplexed in time can also make use of resources available in the frequency domain to compress the occurrence of the ACKs.

• Handling of retransmissions for two or more WDs simultaneously transmitting using CFS-PUR based on MU-MIMO. The retransmissions are subject to be paired with transmission or re-transmissions of the other WDs having the same transmission characteristics e.g., in terms of power and number of repetitions they use.

For supporting CFS-PUR based on MU-MIMO, the downlink aspects should be functional including the handling of acknowledgements and retransmissions, e.g. scheduling retransmissions, as disclosed herein.

One advantage of some embodiments described herein is that the DL aspects of CFS- PUR based on MU-MIMO do not need to be orthogonal for them to work.

The DL aspects of CFS-PUR based on MU-MIMO disclosed herein are not limited to a particular signal to noise ratio (SNR) arrangement for them to work.

In some embodiments, DL transmission on CFS-PURs based on MU-MIMO can be performed in an easy and signaling-efficient way when it is not possible to perform DL transmissions and/or scheduling retransmissions simultaneously to a plurality of WDs.

According to one aspect, a network node is configured to communicate with a plurality of wireless devices, WD. The network node comprises processing circuitry configured to simultaneously receive a plurality of preconfigured uplink resource, PUR, uplink transmissions from a plurality of WDs using contention free shared PUR, CFS-PUR, and to transmit to the plurality of WDs in downlink transmissions that include multiplexed responses to the PUR uplink transmissions.

According to this aspect, in some embodiments, the processing circuitry is further configured to configure a WD with a starting point of a PUR search space window with respect to an end of a physical uplink shared channel, (N)PUSCH, (or any physical uplink shared channel used for NR/NG-RAN) using contention free shared PUR, CFS-PUR. In some embodiments, a starting point of the PUR search space window is predetermined as a function of a cyclic shift and/or a WD identification and/or radio network temporary identifier, RNTI, value using CFS-PUR. In some embodiments, the processing circuitry is further configured to configure different CFS-PUR WDs sharing a PUR resource with different radio network temporary identifier, RNTI, values. In some embodiments, the processing circuitry is further configured to configure WDs transmitting simultaneously over contention free shared PUR, CFS-PUR with a single PUR search space window. In some embodiments, the processing circuitry is further configured to configure different WDs transmitting simultaneously over contention free shared PUR, CFS-PUR, with different PUR search space windows. In some embodiments, the processing circuitry is further configured to multiplex multiple acknowledgements across downlink transmissions using WD offsets. In some embodiments, the processing circuitry is further configured to pair transmissions and/or retransmissions intended for multiple WDs having a same power and/or number of repetitions. In some embodiments, the multiplexing of responses to the PUR uplink transmissions includes transmitting different responses to different WDs on different beams. In some embodiments, the different responses transmitted to different WDs are further distinguished by at least one of: a unique cyclic shift of a reference signal and a unique PUR radio network temporary identifier, RNTI. In some embodiments, different responses to different WDs are distinguished by different cyclic shifts of a demodulation reference signal. In some embodiments, a sequence of cyclic shifts is used that is known to the different WDs. In some embodiments, different responses to the PUR uplink transmissions are transmitted on different frequencies. In some embodiments, radio network temporary identifiers, RNTIs, are used to distinguish downlink control information, DCI, messages used to schedule the responses to the PUR uplink transmissions on radio resource control, RRC, resources.

According to another aspect, a method implemented in a network node in communication with a plurality of wireless devices, WDs, includes simultaneously receiving a plurality of preconfigured uplink resource, PUR, uplink transmissions from a plurality of WDs using contention free shared PUR, CFS-PUR, and transmit to the plurality of WDs in downlink transmissions that include multiplexed responses to the PUR uplink transmissions.

According to this aspect, in some embodiments, the method further includes configuring each of the plurality of WDs with a starting point of a PUR search space window with respect to an end of a physical uplink shared channel, (N)PUSCH (or any physical uplink shared channel used for NR/NG-RAN) using contention free shared PURs, CFS-PUR. In some embodiments, the starting point of a PUR search space window is predetermined as a function of a cyclic shift and/or a WD identification and/or radio network temporary identifier, RNTI, value using CFS-PUR. In some embodiments, the method also includes configuring different CFS-PUR WDs sharing a PUR resource with different radio network temporary identifier, RNTI, values. In some embodiments, the method also includes configuring WDs transmitting simultaneously over contention free shared, CFS, PURs with a single PUR search space window. In some embodiments, the method also includes configuring different WDs transmitting simultaneously over CFS-PUR with different PUR search space windows. In some embodiments, the method also includes multiplexing across downlink transmissions multiple acknowledgements using WD offsets. In some embodiments, the method also includes pairing transmissions or retransmissions intended for multiple WDs having a same power and/or number of repetitions. In some embodiments, the multiplexing of responses to the PUR uplink transmissions includes transmitting different responses to different WDs on different beams. In some embodiments, the different responses transmitted to different WDs are further distinguished by at least one of a unique cyclic shift of a reference signal, and a unique PUR radio network temporary identifier, RNTI. In some embodiments, different responses to different WDs 'are distinguished by different cyclic shifts of a demodulation reference signal. In some embodiments, a sequence of cyclic shifts is used that is known to the different WDs. In some embodiments, different responses to the PUR uplink transmissions are transmitted on different frequencies. In some embodiments, radio network temporary identifiers, RNTIs, are used to distinguish downlink control information, DCI, messages used to schedule the responses on radio resource control, RRC, resources.

According to yet another aspect, a WD is configured to communicate with a network node. The WD includes a radio interface configured to transmit a preconfigured uplink resource, PUR, uplink transmission to the network node and processing circuitry configured to monitor a downlink channel from the network node during a search space window for an acknowledgement, ACK, of receipt of the PUR uplink transmission.

According to this aspect, in some embodiments, the radio interface is further configured to receive from the network node a predetermined starting point of the search space window with respect to an end of a physical uplink shared channel, (N)PUSCH (or any physical uplink shared channel used for NR/NG-RAN), using contention free shared PURs, CFS-PUR. In some embodiments, the radio interface is further configured to receive from the network node a PUR radio network temporary identifier, RNTI, and use the RNTI to determine if the ACK is intended for the WD. In some embodiments, a predetermined starting point of the search space window is an offset based at least in part on a cyclic shift allocated to the WD by the network node. In some embodiments, an ACK intended for the WD is distinguished at least in part by a cyclic shift of a demodulation reference signal. In some embodiments, a sequence of cyclic shifts is used that is known to different WDs. In some embodiments, an ACK intended for the WD is transmitted on a predetermined frequency assigned to the WD. In some embodiments, an ACK intended for the WD is distinguished at least in part by a radio network temporary identifier, RNTI, indicative of a downlink control information, DCI, message used to schedule the ACK.

According to another aspect, a method implemented in a wireless device, WD, includes transmitting a preconfigured uplink resource, PUR, uplink transmission to a network node, and monitoring a downlink channel from the network node during a search space window for an acknowledgement, ACK, of receipt of the PUR uplink transmission.

According to this aspect, in some embodiments, the method also includes receiving from the network node a starting point of the search space window with respect to an end of a physical uplink shared channel, (N)PUSCH (or any physical uplink shared channel used for NR/NG-RAN), using contention free shared PURs, CFS-PUR. In some embodiments, the method also includes receiving from the network node a PUR radio network temporary identifier, RNTI, and using the RNTI to determine if the ACK is intended for the WD. In some embodiments, a predetermined starting point of the search space window is an offset based at least in part on a cyclic shift allocated to the WD by the network node. In some embodiments, an ACK intended for the WD is distinguished at least in part by a cyclic shift of a demodulation reference signal. In some embodiments, a sequence of cyclic shifts is used that is known to different WDs. In some embodiments, an ACK intended for the WD is transmitted on a predetermined frequency assigned to the WD. In some embodiments, an ACK intended for the WD is distinguished at least in part by a radio network temporary identifier, RNTI, indicative of a downlink control information, DCI, message used to schedule the ACK.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the present embodiments, and the attendant advantages and features thereof, will be more readily understood by reference to the following detailed description when considered in conjunction with the accompanying drawings wherein:

FIG. 1 is a schematic diagram of an exemplary network architecture illustrating a communication system connected via an intermediate network to a host computer according to the principles in the present disclosure;

FIG. 2 is a block diagram of a host computer communicating via a network node with a wireless device over an at least partially wireless connection according to some embodiments of the present disclosure;

FIG. 3 is a flowchart illustrating exemplary methods implemented in a communication system including a host computer, a network node and a wireless device for executing a client application at a wireless device according to some embodiments of the present disclosure;

FIG. 4 is a flowchart illustrating exemplary methods implemented in a communication system including a host computer, a network node and a wireless device for receiving user data at a wireless device according to some embodiments of the present disclosure;

FIG. 5 is a flowchart illustrating exemplary methods implemented in a communication system including a host computer, a network node and a wireless device for receiving user data from the wireless device at a host computer according to some embodiments of the present disclosure;

FIG. 6 is a flowchart illustrating exemplary methods implemented in a communication system including a host computer, a network node and a wireless device for receiving user data at a host computer according to some embodiments of the present disclosure;

FIG. 7 is a flowchart of an exemplary process in a network node for downlink aspects of contention free shared preconfigured uplink resources (CFS-PUR) on multi-user multiple input multiple output (MU-MIMO) transmissions;

FIG. 8 is a flowchart of an exemplary process in a wireless device for downlink aspects of contention free shared preconfigured uplink resources (CFS-PUR) on multi-user multiple input multiple output (MU-MIMO) transmissions;

FIG. 9 is a flowchart of an exemplary process in a network node for downlink aspects of contention free shared preconfigured uplink resources (CFS-PUR) on multi-user multiple input multiple output (MU-MIMO) transmissions;

FIG. 10 is a flowchart of an exemplary process in a wireless device for downlink aspects of contention free shared preconfigured uplink resources (CFS-PUR) on multi-user multiple input multiple output (MU-MIMO) transmissions;

FIG. 11 shows Ll-ACK multiplexing for 3 WDs using different search space windows in CFS-PUR based on MU-MIMO;

FIG. 12 shows Ll-ACK multiplexing for 3 WDs using a single search space window in CFS-PUR based on MU-MIMO; FIG. 13 shows Ll-ACK multiplexing for 3 WDs combining the use of aggregation levels and a single search space in CFS-PUR based on MU-MIMO;

FIG. 14 shows L2/L3-ACK multiplexing for 3 WDs using several search space windows in CFS-PUR based on MU-MIMO;

FIG. 15 shows L2/L3-ACK multiplexing for 3 WDs using a single search space window in CFS-PUR based on MU-MIMO; and

FIG. 16 shows L2/L3-ACK multiplexing for 3 WDs combining the use of aggregation levels and a single search space window in CFS-PUR based on MU-MIMO.

DETAILED DESCRIPTION

Before describing in detail exemplary embodiments, it is noted that the embodiments reside primarily in combinations of apparatus components and processing steps related to assessing downlink aspects of contention free shared preconfigured uplink resources (CFS- PUR) on multi-user multiple input multiple output (MU-MIMO) transmissions. Accordingly, components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein. Like numbers refer to like elements throughout the description.

As used herein, relational terms, such as “first” and “second,” “top” and “bottom,” and the like, may be used solely to distinguish one entity or element from another entity or element without necessarily requiring or implying any physical or logical relationship or order between such entities or elements. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the concepts described herein. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes” and/or “including” when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

In embodiments described herein, the joining term, “in communication with” and the like, may be used to indicate electrical or data communication, which may be accomplished by physical contact, induction, electromagnetic radiation, radio signaling, infrared signaling or optical signaling, for example. One having ordinary skill in the art will appreciate that multiple components may interoperate and modifications and variations are possible of achieving the electrical and data communication.

In some embodiments described herein, the term “coupled,” “connected,” and the like, may be used herein to indicate a connection, although not necessarily directly, and may include wired and/or wireless connections.

The term “network node” used herein can be any kind of network node comprised in a radio network which may further comprise any of base station (BS), radio base station, base transceiver station (BTS), base station controller (BSC), radio network controller (RNC), g Node B (gNB), evolved Node B (eNB or eNodeB), Node B, multi-standard radio (MSR) radio node such as MSR BS, multi-cell/multicast coordination entity (MCE), integrated access and backhaul (IAB) node, relay node, donor node controlling relay, radio access point (AP), transmission points, transmission nodes, Remote Radio Unit (RRU) Remote Radio Head (RRH), a core network node (e.g., mobile management entity (MME), self-organizing network (SON) node, a coordinating node, positioning node, MDT node, etc.), an external node (e.g., 3rd party node, anode external to the current network), nodes in distributed antenna system (DAS), a spectrum access system (SAS) node, an element management system (EMS), etc. The network node may also comprise test equipment. The term “radio node” used herein may be used to also denote a wireless device (WD) such as a wireless device (WD) or a radio network node.

In some embodiments, the non-limiting terms wireless device (WD) or a user equipment (UE) are used interchangeably. The WD herein can be any type of wireless device capable of communicating with a network node or another WD over radio signals, such as wireless device (WD). The WD may also be a radio communication device, target device, device to device (D2D) WD, machine type WD or WD capable of machine to machine communication (M2M), low-cost and/or low-complexity WD, a sensor equipped with WD, Tablet, mobile terminals, smart phone, laptop embedded equipped (LEE), laptop mounted equipment (LME), USB dongles, Customer Premises Equipment (CPE), an Internet of Things (IoT) device, or a Narrowband IoT (NB-IoT) device, etc.

Also, in some embodiments the generic term “radio network node” is used. It can be any kind of a radio network node which may comprise any of base station, radio base station, base transceiver station, base station controller, network controller, RNC, evolved Node B (eNB), Node B, gNB, Multi-cell/multicast Coordination Entity (MCE), IAB node, relay node, access point, radio access point, Remote Radio Unit (RRU) Remote Radio Head (RRH).

Note that although terminology from one particular wireless system, such as, for example, 3GPP LTE and/or New Radio (NR), may be used in this disclosure, this should not be seen as limiting the scope of the disclosure to only the aforementioned system. Other wireless systems, including without limitation Wide Band Code Division Multiple Access (WCDMA), Worldwide Interoperability for Microwave Access (WiMax), Ultra Mobile Broadband (UMB) and Global System for Mobile Communications (GSM), may also benefit from exploiting the ideas covered within this disclosure.

Note further, that functions described herein as being performed by a wireless device or a network node may be distributed over a plurality of wireless devices and/or network nodes. In other words, it is contemplated that the functions of the network node and wireless device described herein are not limited to performance by a single physical device and, in fact, can be distributed among several physical devices.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms used herein should be interpreted as having a meaning that is consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

Embodiments provide for assessing downlink aspects of contention free shared preconfigured uplink resources (CFS-PUR) on multi-user multiple input multiple output (MU-MIMO) transmissions. For CFS-PUR based on MU-MIMO, how the reception of the ACK will be performed has not been discussed by 3GPP since each of the two or more WDs that have transmitted simultaneously in the UL will be expecting an ACK within a certain timeframe. In the discussion below, the reception of a LI -ACK and a L2/L3-ACK are separately assessed since they make use of different physical channels.

Referring now to the drawing figures, in which like elements are referred to by like reference numerals, there is shown in FIG. 1 a schematic diagram of a communication system 10, according to an embodiment, such as a 3GPP-type cellular network that may support standards such as LTE and/or NR (5G), which comprises an access network 12, such as a radio access network, and a core network 14. The access network 12 comprises a plurality of network nodes 16a, 16b, 16c (referred to collectively as network nodes 16), such as NBs, eNBs, gNBs or other types of wireless access points, each defining a corresponding coverage area 18a, 18b, 18c (referred to collectively as coverage areas 18). Each network node 16a, 16b, 16c is connectable to the core network 14 over a wired or wireless connection 20. A first wireless device (WD) 22a located in coverage area 18a is configured to wirelessly connect to, or be paged by, the corresponding network node 16a. A second WD 22b in coverage area 18b is wirelessly connectable to the corresponding network node 16b. While a plurality of WDs 22a, 22b (collectively referred to as wireless devices 22) are illustrated in this example, the disclosed embodiments are equally applicable to a situation where a sole WD is in the coverage area or where a sole WD is connecting to the corresponding network node 16. Note that although only two WDs 22 and three network nodes 16 are shown for convenience, the communication system may include many more WDs 22 and network nodes 16.

Also, it is contemplated that a WD 22 can be in simultaneous communication and/or configured to separately communicate with more than one network node 16 and more than one type of network node 16. For example, a WD 22 can have dual connectivity with a network node 16 that supports LTE and the same or a different network node 16 that supports NR. As an example, WD 22 can be in communication with an eNB for LTE/E-UTRAN and a gNB for NR/NG-RAN.

The communication system 10 may itself be connected to a host computer 24, which may be embodied in the hardware and/or software of a standalone server, a cloud- implemented server, a distributed server or as processing resources in a server farm. The host computer 24 may be under the ownership or control of a service provider, or may be operated by the service provider or on behalf of the service provider. The connections 26, 28 between the communication system 10 and the host computer 24 may extend directly from the core network 14 to the host computer 24 or may extend via an optional intermediate network 30. The intermediate network 30 may be one of, or a combination of more than one of, a public, private or hosted network. The intermediate network 30, if any, may be a backbone network or the Internet. In some embodiments, the intermediate network 30 may comprise two or more sub-networks (not shown).

The communication system of FIG. 1 as a whole enables connectivity between one of the connected WDs 22a, 22b and the host computer 24. The connectivity may be described as an over-the-top (OTT) connection. The host computer 24 and the connected WDs 22a, 22b are configured to communicate data and/or signaling via the OTT connection, using the access network 12, the core network 14, any intermediate network 30 and possible further infrastructure (not shown) as intermediaries. The OTT connection may be transparent in the sense that at least some of the participating communication devices through which the OTT connection passes are unaware of routing of uplink and downlink communications. For example, a network node 16 may not or need not be informed about the past routing of an incoming downlink communication with data originating from a host computer 24 to be forwarded (e.g., handed over) to a connected WD 22a. Similarly, the network node 16 need not be aware of the future routing of an outgoing uplink communication originating from the WD 22a towards the host computer 24.

A network node 16 is configured to include an ACK transmitter 32 which is configured to, responsive to receiving the PUR uplink transmission, transmit to the WD an acknowledgement (ACK) at a time following a physical uplink shared channel (PUSCH) transmission so that the ACK arrives at the WD during a PUR search space window. A wireless device 22 is configured to include a downlink channel monitor 34 configured to monitor a downlink channel from the network node during a search space window for an acknowledgement (ACK) of receipt of the PUR uplink transmission, the monitoring beginning at a predetermined starting point after an end of a physical uplink shared channel (PUSCH) transmission by the WD.

Example implementations, in accordance with an embodiment, of the WD 22, network node 16 and host computer 24 discussed in the preceding paragraphs will now be described with reference to FIG. 2. In a communication system 10, a host computer 24 comprises hardware (HW) 38 including a communication interface 40 configured to set up and maintain a wired or wireless connection with an interface of a different communication device of the communication system 10. The host computer 24 further comprises processing circuitry 42, which may have storage and/or processing capabilities. The processing circuitry 42 may include a processor 44 and memory 46. In particular, in addition to or instead of a processor, such as a central processing unit, and memory, the processing circuitry 42 may comprise integrated circuitry for processing and/or control, e.g., one or more processors and/or processor cores and/or FPGAs (Field Programmable Gate Array) and/or ASICs (Application Specific Integrated Circuitry) adapted to execute instructions. The processor 44 may be configured to access (e.g., write to and/or read from) memory 46, which may comprise any kind of volatile and/or nonvolatile memory, e.g., cache and/or buffer memory and/or RAM (Random Access Memory) and/or ROM (Read-Only Memory) and/or optical memory and/or EPROM (Erasable Programmable Read-Only Memory).

Processing circuitry 42 may be configured to control any of the methods and/or processes described herein and/or to cause such methods, and/or processes to be performed, e.g., by host computer 24. Processor 44 corresponds to one or more processors 44 for performing host computer 24 functions described herein. The host computer 24 includes memory 46 that is configured to store data, programmatic software code and/or other information described herein. In some embodiments, the software 48 and/or the host application 50 may include instructions that, when executed by the processor 44 and/or processing circuitry 42, causes the processor 44 and/or processing circuitry 42 to perform the processes described herein with respect to host computer 24. The instructions may be software associated with the host computer 24.

The software 48 may be executable by the processing circuitry 42. The software 48 includes a host application 50. The host application 50 may be operable to provide a service to a remote user, such as a WD 22 connecting via an OTT connection 52 terminating at the WD 22 and the host computer 24. In providing the service to the remote user, the host application 50 may provide user data which is transmitted using the OTT connection 52. The “user data” may be data and information described herein as implementing the described functionality. In one embodiment, the host computer 24 may be configured for providing control and functionality to a service provider and may be operated by the service provider or on behalf of the service provider. The processing circuitry 42 of the host computer 24 may enable the host computer 24 to observe, monitor, control, transmit to and/or receive from the network node 16 and or the wireless device 22.

The communication system 10 further includes a network node 16 provided in a communication system 10 and including hardware 58 enabling it to communicate with the host computer 24 and with the WD 22. The hardware 58 may include a communication interface 60 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of the communication system 10, as well as a radio interface 62 for setting up and maintaining at least a wireless connection 64 with a WD 22 located in a coverage area 18 served by the network node 16. The radio interface 62 may be formed as or may include, for example, one or more RF transmitters, one or more RF receivers, and/or one or more RF transceivers. In some embodiments, the radio interface 62 includes an ACK transmitter 32 configured to transmit an ACK to the WD 22. The communication interface 60 may be configured to facilitate a connection 66 to the host computer 24. The connection 66 may be direct or it may pass through a core network 14 of the communication system 10 and/or through one or more intermediate networks 30 outside the communication system 10.

In the embodiment shown, the hardware 58 of the network node 16 further includes processing circuitry 68. The processing circuitry 68 may include a processor 70 and a memory 72. In particular, in addition to or instead of a processor, such as a central processing unit, and memory, the processing circuitry 68 may comprise integrated circuitry for processing and/or control, e.g., one or more processors and/or processor cores and/or FPGAs (Field Programmable Gate Array) and/or ASICs (Application Specific Integrated Circuitry) adapted to execute instructions. The processor 70 may be configured to access (e.g., write to and/or read from) the memory 72, which may comprise any kind of volatile and/or nonvolatile memory, e.g., cache and/or buffer memory and/or RAM (Random Access Memory) and/or ROM (Read-Only Memory) and/or optical memory and/or EPROM (Erasable Programmable Read-Only Memory).

Thus, the network node 16 further has software 74 stored internally in, for example, memory 72, or stored in external memory (e.g., database, storage array, network storage device, etc.) accessible by the network node 16 via an external connection. The software 74 may be executable by the processing circuitry 68. The processing circuitry 68 may be configured to control any of the methods and/or processes described herein and/or to cause such methods, and/or processes to be performed, e.g., by network node 16. Processor 70 corresponds to one or more processors 70 for performing network node 16 functions described herein. The memory 72 is configured to store data, programmatic software code and/or other information described herein. In some embodiments, the software 74 may include instructions that, when executed by the processor 70 and/or processing circuitry 68, causes the processor 70 and/or processing circuitry 68 to perform the processes described herein with respect to network node 16. For example, processing circuitry 68 of the network node 16 may include ACK transmitter 32 which is configured to, responsive to receiving the PUR uplink transmission, transmit to the WD an acknowledgement (ACK) at a time following a physical uplink shared channel (PUSCH) transmission so that the ACK arrives at the WD during a PUR search space window.

The communication system 10 further includes the WD 22 already referred to. The WD 22 may have hardware 80 that may include a radio interface 82 configured to set up and maintain a wireless connection 64 with a network node 16 serving a coverage area 18 in which the WD 22 is currently located. The radio interface 82 may be formed as or may include, for example, one or more RF transmitters, one or more RF receivers, and/or one or more RF transceivers.

The hardware 80 of the WD 22 further includes processing circuitry 84. The processing circuitry 84 may include a processor 86 and memory 88. In particular, in addition to or instead of a processor, such as a central processing unit, and memory, the processing circuitry 84 may comprise integrated circuitry for processing and/or control, e.g., one or more processors and/or processor cores and/or FPGAs (Field Programmable Gate Array) and/or ASICs (Application Specific Integrated Circuitry) adapted to execute instructions. The processor 86 may be configured to access (e.g., write to and/or read from) memory 88, which may comprise any kind of volatile and/or nonvolatile memory, e.g., cache and/or buffer memory and/or RAM (Random Access Memory) and/or ROM (Read-Only Memory) and/or optical memory and/or EPROM (Erasable Programmable Read-Only Memory).

Thus, the WD 22 may further comprise software 90, which is stored in, for example, memory 88 at the WD 22, or stored in external memory (e.g., database, storage array, network storage device, etc.) accessible by the WD 22. The software 90 may be executable by the processing circuitry 84. The software 90 may include a client application 92. The client application 92 may be operable to provide a service to a human or non-human user via the WD 22, with the support of the host computer 24. In the host computer 24, an executing host application 50 may communicate with the executing client application 92 via the OTT connection 52 terminating at the WD 22 and the host computer 24. In providing the service to the user, the client application 92 may receive request data from the host application 50 and provide user data in response to the request data. The OTT connection 52 may transfer both the request data and the user data. The client application 92 may interact with the user to generate the user data that it provides.

The processing circuitry 84 may be configured to control any of the methods and/or processes described herein and/or to cause such methods, and/or processes to be performed, e.g., by WD 22. The processor 86 corresponds to one or more processors 86 for performing WD 22 functions described herein. The WD 22 includes memory 88 that is configured to store data, programmatic software code and/or other information described herein. In some embodiments, the software 90 and/or the client application 92 may include instructions that, when executed by the processor 86 and/or processing circuitry 84, causes the processor 86 and/or processing circuitry 84 to perform the processes described herein with respect to WD 22. For example, the processing circuitry 84 of the wireless device 22 may include downlink channel monitor 34 configured to monitor a downlink channel from the network node 16 during a search space window for an acknowledgement (ACK) of receipt of the PUR uplink transmission, the monitoring beginning at a predetermined starting point after an end of a physical uplink shared channel (PUSCH) transmission by the WD.

In some embodiments, the inner workings of the network node 16, WD 22, and host computer 24 may be as shown in FIG. 2 and independently, the surrounding network topology may be that of FIG. 1.

In FIG. 2, the OTT connection 52 has been drawn abstractly to illustrate the communication between the host computer 24 and the wireless device 22 via the network node 16, without explicit reference to any intermediary devices and the precise routing of messages via these devices. Network infrastructure may determine the routing, which it may be configured to hide from the WD 22 or from the service provider operating the host computer 24, or both. While the OTT connection 52 is active, the network infrastructure may further take decisions by which it dynamically changes the routing (e.g., on the basis of load balancing consideration or reconfiguration of the network).

The wireless connection 64 between the WD 22 and the network node 16 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments improve the performance of OTT services provided to the WD 22 using the OTT connection 52, in which the wireless connection 64 may form the last segment. More precisely, the teachings of some of these embodiments may improve the data rate, latency, and/or power consumption and thereby provide benefits such as reduced user waiting time, relaxed restriction on file size, better responsiveness, extended battery lifetime, etc.

In some embodiments, a measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve. There may further be an optional network functionality for reconfiguring the OTT connection 52 between the host computer 24 and WD 22, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection 52 may be implemented in the software 48 of the host computer 24 or in the software 90 of the WD 22, or both. In embodiments, sensors (not shown) may be deployed in or in association with communication devices through which the OTT connection 52 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software 48, 90 may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 52 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect the network node 16, and it may be unknown or imperceptible to the network node 16. Some such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary WD signaling facilitating the host computer’s 24 measurements of throughput, propagation times, latency and the like. In some embodiments, the measurements may be implemented in that the software 48, 90 causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 52 while it monitors propagation times, errors etc.

Thus, in some embodiments, the host computer 24 includes processing circuitry 42 configured to provide user data and a communication interface 40 that is configured to forward the user data to a cellular network for transmission to the WD 22. In some embodiments, the cellular network also includes the network node 16 with a radio interface 62. In some embodiments, the network node 16 is configured to, and/or the network node’s 16 processing circuitry 68 is configured to perform the functions and/or methods described herein for preparing/initiating/maintaining/supporting/ending a transmission to the WD 22, and/or preparing/terminating/maintaining/supporting/ending in receipt of a transmission from the WD 22.

In some embodiments, the host computer 24 includes processing circuitry 42 and a communication interface 40 that is configured to a communication interface 40 configured to receive user data originating from a transmission from a WD 22 to a network node 16. In some embodiments, the WD 22 is configured to, and/or comprises a radio interface 82 and/or processing circuitry 84 configured to perform the functions and/or methods described herein for preparing/initiating/maintaining/supporting/ending a transmission to the network node 16, and/or preparing/terminating/maintaining/supporting/ending in receipt of a transmission from the network node 16.

Although FIGS. 1 and 2 show various “units” such as downlink channel monitor 34 as being within a respective processor, it is contemplated that these units may be implemented such that a portion of the unit is stored in a corresponding memory within the processing circuitry. In other words, the units may be implemented in hardware or in a combination of hardware and software within the processing circuitry.

FIG. 3 is a flowchart illustrating an exemplary method implemented in a communication system, such as, for example, the communication system of FIGS. 1 and 2, in accordance with one embodiment. The communication system may include a host computer 24, a network node 16 and a WD 22, which may be those described with reference to FIG. 2. In a first step of the method, the host computer 24 provides user data (Block SI 00). In an optional substep of the first step, the host computer 24 provides the user data by executing a host application, such as, for example, the host application 50 (Block SI 02). In a second step, the host computer 24 initiates a transmission carrying the user data to the WD 22 (Block SI 04). In an optional third step, the network node 16 transmits to the WD 22 the user data which was carried in the transmission that the host computer 24 initiated, in accordance with the teachings of the embodiments described throughout this disclosure (Block SI 06). In an optional fourth step, the WD 22 executes a client application, such as, for example, the client application 92, associated with the host application 50 executed by the host computer 24 (Block SI 08).

FIG. 4 is a flowchart illustrating an exemplary method implemented in a communication system, such as, for example, the communication system of FIG. 1, in accordance with one embodiment. The communication system may include a host computer 24, a network node 16 and a WD 22, which may be those described with reference to FIGS. 1 and 2. In a first step of the method, the host computer 24 provides user data (Block SI 10). In an optional substep (not shown) the host computer 24 provides the user data by executing a host application, such as, for example, the host application 50. In a second step, the host computer 24 initiates a transmission carrying the user data to the WD 22 (Block SI 12). The transmission may pass via the network node 16, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional third step, the WD 22 receives the user data carried in the transmission (Block SI 14).

FIG. 5 is a flowchart illustrating an exemplary method implemented in a communication system, such as, for example, the communication system of FIG. 1, in accordance with one embodiment. The communication system may include a host computer 24, a network node 16 and a WD 22, which may be those described with reference to FIGS. 1 and 2. In an optional first step of the method, the WD 22 receives input data provided by the host computer 24 (Block SI 16). In an optional substep of the first step, the WD 22 executes the client application 92, which provides the user data in reaction to the received input data provided by the host computer 24 (Block SI 18). Additionally, or alternatively, in an optional second step, the WD 22 provides user data (Block S120). In an optional substep of the second step, the WD provides the user data by executing a client application, such as, for example, client application 92 (Block S122). In providing the user data, the executed client application 92 may further consider user input received from the user. Regardless of the specific manner in which the user data was provided, the WD 22 may initiate, in an optional third substep, transmission of the user data to the host computer 24 (Block SI 24). In a fourth step of the method, the host computer 24 receives the user data transmitted from the WD 22, in accordance with the teachings of the embodiments described throughout this disclosure (Block S126).

FIG. 6 is a flowchart illustrating an exemplary method implemented in a communication system, such as, for example, the communication system of FIG. 1, in accordance with one embodiment. The communication system may include a host computer 24, a network node 16 and a WD 22, which may be those described with reference to FIGS. 1 and 2. In an optional first step of the method, in accordance with the teachings of the embodiments described throughout this disclosure, the network node 16 receives user data from the WD 22 (Block S128). In an optional second step, the network node 16 initiates transmission of the received user data to the host computer 24 (Block S130). In a third step, the host computer 24 receives the user data carried in the transmission initiated by the network node 16 (Block SI 32).

FIG. 7 is a flowchart of an exemplary process in a network node 16 for assessing downlink aspects of contention free shared preconfigured uplink resources (CFS-PUR) on multi-user multiple input multiple output (MU-MIMO) transmissions. One or more blocks described herein may be performed by one or more elements of network node 16 such as by one or more of processing circuitry 68, processor 70, radio interface 62 (including ACK transmitter 32) and/or communication interface 60. Network node 16 such as via processing circuitry 68 and/or processor 70 and/or radio interface 62 and/or communication interface 60 is configured to simultaneously receive a plurality of preconfigured uplink resource, PUR, uplink transmissions from a plurality of WDs using contention free shared PUR, CFS-PUR (Block SI 34). The process also includes transmitting, in downlink transmission, multiplexed responses to the PUR uplink transmissions (Block S136). FIG. 8 is a flowchart of an exemplary process in a wireless device 22 according to some embodiments of the present disclosure. One or more blocks described herein may be performed by one or more elements of wireless device 22 such as by one or more of processing circuitry 84 (including downlink channel monitor 34), processor 86, radio interface 82 and/or communication interface 60. Wireless device 22 such as via processing circuitry 84 and/or processor 86 and/or radio interface 82 is configured to transmit a preconfigured uplink resource (PUR) uplink transmission to the network node (Block S138). The process also includes monitoring a downlink channel from the network node during a search space window for an acknowledgement (ACK) of receipt of the PUR uplink transmission (Block S140).

FIG. 9 is a flowchart of an exemplary process in a network node for downlink aspects of contention free shared preconfigured uplink resources (CFS-PUR) on multi-user multiple input multiple output (MU-MIMO) transmissions. One or more blocks described herein may be performed by one or more elements of network node 16 such as by one or more of processing circuitry 68, processor 70, radio interface 62 (including ACK transmitter 32) and/or communication interface 60. Network node 16 such as via processing circuitry 68 and/or processor 70 and/or radio interface 62 and/or communication interface 60 is configured to receive a preconfigured uplink resource (PUR) uplink transmission from the WD (Block S142). The process also includes, responsive to receiving the PUR uplink transmission, transmitting to the WD an acknowledgement (ACK) at a time following a physical uplink shared channel (PUSCH) transmission so that the ACK arrives at the WD during a PUR search space window (Block S144).

FIG. 10 is a flowchart of an exemplary process in a wireless device for downlink aspects of contention free shared preconfigured uplink resources (CFS-PUR) on multi-user multiple input multiple output (MU-MIMO) transmissions. One or more blocks described herein may be performed by one or more elements of wireless device 22 such as by one or more of processing circuitry 84 (including downlink channel monitor 34), processor 86, radio interface 82 and/or communication interface 60. Wireless device 22 such as via processing circuitry 84 and/or processor 86 and/or radio interface 82 is configured to transmit a preconfigured uplink resource (PUR) uplink transmission to the network node (Block S146). The process also includes monitoring a downlink channel from the network node during a search space window for an acknowledgement (ACK) of receipt of the PUR uplink transmission, the monitoring beginning at a predetermined starting point after an end of a physical uplink shared channel (PUSCH) transmission by the WD (Block S148).

Having described the general process flow of arrangements of the disclosure and having provided examples of hardware and software arrangements for implementing the processes and functions of the disclosure, the sections below provide details and examples of arrangements for assessing downlink aspects of contention free shared preconfigured uplink resources (CFS-PUR) on multi-user multiple input multiple output (MU-MIMO) transmissions.

In some embodiments, the Ll-ACK makes use of downlink control information (DCI) using for example Format 6-OA or DCI Format 6-OB (or Format NO for NB-IoT or any Format used for NR/NG-RAN) depending on the coverage region. Accordingly, in some embodiments, if the PUR uplink transmission was successfully received by the network node 16, the WD 22 should receive an Ll-ACK in 4 ms at the earliest after the end of the PUSCH transmission. That is, 4 ms after the end of PUSCH, the WD 22 should start monitoring the DL in principle until the end of the so called “search space window”.

For CFS-PUR based on MU-MIMO, two or more WDs 22 will perform their UL transmissions simultaneously, and in that case in one embodiment the WDs 22 are configured with “PUR search space windows” of the same or different lengths that are (e.g., using configurable WD 22 specific offsets) multiplexed in time. The multiplexing may be done in such a way that each of the WDs 22 can receive the Ll-ACK in a collision free manner. FIG. 11 is an example diagram showing Ll-ACK multiplexing for 3 WDs 22 using different search space windows in CFS-PUR based on MU-MIMO.

In one embodiment, the starting point of the “PUR search space window” with respect to the end of the PUSCH transmission, i.e., an offset for the start of the PUR search space, is signaled to each of the WDs 22 using CFS-PUR.

In one embodiment, the starting point of the “PUR search space window” with respect to the end of the PUSCH transmission is predetermined via the processing circuitry 68 as a function of the unique cyclic shift and/or WD-ID and/or radio network temporary identifier (RNTI) value (if not shared with other WDs 22) given to each of the WDs 22 using CFS- PUR. In some embodiments, the starting point and the length of the ‘PUR search space window’ are the same, but depending on the cyclic shift allocated to a WD 22 for MU- MIMO, the PUR search space occasions within the window uses a time offset. In another embodiment, the CFS-PUR WDs 22 sharing a PUR resource are configured with different PUR RNTIs, which are used to distinguish for which WD 22 the LI ACK is intended. In another embodiment, if PUR RNTIs are shared by multiple WDs 22, a contention resolution mechanism can resolve the contention.

In one embodiment, the WDs 22 that transmitted simultaneously over CFS-PUR are configured, via the network node 16, with a single PUR search space window, and the network node 16 multiplexes the Ll-ACKs of different WDs 22 in time and/or frequency (at different aggregation levels). FIG. 12 shows Ll-ACK multiplexing for 3 WDs 22 using a single search space window in CFS-PUR based on MU-MIMO. FIG. 13 shows Ll-ACK multiplexing for 3 WDs 22 combining the use of aggregation levels and a single search space in CFS-PUR based on MU-MIMO. In one embodiment, the starting point of the “M(N)PDCCH” (physical downlink control channel) is with respect to the end of the PUSCH transmission, i.e., an offset for the start of the M(N)PDCCH, is signaled to each of the WDs 22 using CFS-PUR. In one embodiment, the starting point of the “M(N)PDCCH” with respect to the end of the PUSCH transmission is predetermined via the processing circuitry 68 as a function of the unique cyclic shift and/or WD-ID and/or RNTI value (if not shared with other WDs 22) given to each of the WDs 22 using CFS-PUR.

As described above, the largest gains from CFS-PUR, e.g., using MU-MIMO, may be obtained if there is a symmetric resource utilization between the uplink and downlink. For example, if a number of N WDs 22 can simultaneously transmit in the same (N)PUSCH resource, the data transmissions from these N WDs 22 can be acknowledged (for example by a network node 16) simultaneously without taking a longer time.

In one embodiment for MU-MIMO, the network node 16 transmits, such as for example via the radio interface 62, the ACKs using beamforming to the WDs 22. In other words, MU-MIMO relies on uplink transmissions being received from “different directions”, using the cyclic shifts for the DMRS, for the network node 16 to be able to decode the simultaneous transmissions. Therefore, the network node 16 could apply beamforming to transmit the ACKs to WDs 22 in “different directions”. The solution could further rely on the use of the different cyclic shifts and reciprocity of the channel. The WDs 22 may use different PUR RNTIs to ensure that the LI ACK transmitted to a WD 22 is distinguishable from the LI ACKs transmitted to the other WDs 22 (the same non-CFS-PUR DCI format, e.g., format 6-OA and 6-OB, may be re-used). In another embodiment, a new DCI format is used for CFS-PUR, where for example, a bit string is used corresponding to the different cyclic shifts used for MU-MIMO. That is, instead of the LI ACK containing 1 bit information for the acknowledgement, it instead contains 2, 4, or 8 bits corresponding to the DMRS cyclic shifts used for MU-MIMO. The order of the shifts could be pre-determined such that the WD 22 can determine, via the processing circuitry 84, which bit of the bit string carriers its ACK without further information. One example is given below using 4 cyclic DMRS shifts, where all data transmissions are acknowledged except for the data transmission for the WD 22 which has been configured with cyclic shift 3 for DMRS:

In another embodiment, acknowledgements are sent simultaneously, such as for example via the radio interface 62, to multiple WDs 22 using an RNTI shared by the WDs 22 using UL resources at the same time instant. This RNTI could be the PUR RNTI or another RNTI used only for the purpose of sharing hybrid automatic repeat request (HARQ) feedback or acknowledgements of the CFS-PUR transmissions.

In some embodiments, the L2/L3-ACK may make use of DCI using for example Format 6-1 A or DCI Format 6-1B (or Format NO for NB-IoT or any Format used for NR/NG- RAN) depending on the coverage region, and an (N)PDSCH and physical uplink control channel (PUCCH) (or NPUSCH Format 2 in case of NB-IoT or any Format used for NR/NG- RAN to acknowledge the L2/L3 signaling). If the PUR uplink transmission was successfully received by the network node 16, the WD 22 may expect to receive an L2/L3-ACK within, for example, 4 ms at the earliest after the end of the (N)PUSCH transmission. That is, 4 ms after the end of (N)PUSCH, the WD 22 should start monitoring the DL control channel in principle until the end of the so called “PUR search space window”.

For CFS-PUR based on MU-MIMO, two or more WDs 22 may perform their UL transmissions simultaneously, and in that case, in one embodiment, the WDs 22 are configured with “PUR search space windows” of same or different lengths. These search windows may be multiplexed in time with sufficient margin for each to accommodate M(N)PDCCH, PDSCH and PUCCH (PUSCH Format 2 for NB-IoT) such that each of the WDs 22 can receive the L2/L3-ACK in a collision free manner.

In one embodiment, the starting point of the “PUR search space window” with respect to the end of the PUSCH transmission is signaled, via radio interface 62, to each of the WDs 22 using CFS-PUR. In one embodiment, the starting point of the “PUR search space window” with respect to the end of the PUSCH transmission is predetermined, via the processing circuitry 68, as a function of the unique cyclic shift and/or WD-ID and/or RNTI value (if not shared with other WDs 22) given to each of the WDs 22 using CFS-PUR.

In another embodiment, since PUCCH (or NPUSCH Format 2 in case of NB-IoT) corresponds to an UL transmission, the UL transmission can be turned-off and/or an additional offset can be specified so as to avoid a collision with the UL transmissions (e.g., other PUCCH) of adjacent WDs 22 using PUR. FIG. 14 shows an example diagram of L2/L3-ACK multiplexing for 3 WDs 22 using several search space windows in CFS-PUR based on MU-MIMO. In another embodiment, the CFS-PUR WDs 22 sharing a PUR resource are configured via the network node 16 with different PUR RNTIs, which are used to distinguish the DCI transmissions used to schedule the DL RRC messages (i.e., L2/L3 ACKs). For this embodiment, the network node 16 may have to ensure that WDs 22 are configured with different PUR RNTIs. Yet in another embodiment, if some WDs 22 are configured with the same PUR RNTI value, a contention resolution mechanism is used to distinguish between WDs 22.

In another embodiment, the same PUR RNTI is used an/or configured for all WDs 22 in the same CFS-PUR resource. Then, for which WD 22 the DL RRC message (L2/L3 ACK) is intended is distinguished by using the cyclic DMRS shift. In one example, the cyclic DMRS shift is added as an information element in the DL RRC message (to be determined by the 3 GPP).

In one embodiment, the PUR (re-)configuration also includes the unique cyclic shifts and/or orthogonal code for multiplexing PUCCH transmissions of different CFS-PUR WDs 22 in the same time-frequency resources. In one embodiment, the starting point of the “M(N)PDCCH” is with respect to the end of the PUSCH transmission, i.e., an offset for the start of the M(N)PDCCH, is signaled, via radio interface 62, to each of the WDs 22 using CFS-PUR. FIG. 15 shows L2/L3-ACK multiplexing for 3 WDs 22 using a single search space window in CFS-PUR based on MU-MIMO. FIG. 16 shows L2/L3-ACK multiplexing for 3 WDs 22 combining the use of aggregation levels and a single search space window in CFS-PUR based on MU-MIMO.

In one embodiment, the starting point of the “M(N)PDCCH” with respect to the end of the PUSCH transmission may be predetermined, such as for example via the processing circuitry 68, as a function of the unique cyclic shift and/or WD-ID and/or RNTI value (if not shared with other WDs 22) given to each of the WDs 22 using CFS-PUR. In one embodiment, the starting point of the “(N)PDSCH” is with respect to the end of the PUSCH transmission, i.e., an offset for the start of the (N)PDSCH, is signaled, via the radio interface 62, to each of the WDs 22 using CFS-PUR. In one embodiment, the starting point of the “(N)PDSCH” with respect to the end of the PUSCH transmission is predetermined via the processing circuitry 68 as a function of the unique cyclic shift and/or WD-ID and/or RNTI value (if not shared with other WDs 22) given to each of the WDs 22 using CFS-PUR.

In one embodiment, in the L2/L3-ACK multiplexing for CFs-PUR in MU-MIMO, M(N)PDCCH and PDSCH can be transmitted via the radio interface 62 in the same or different frequencies (e.g., narrow bands). Upon an unsuccessful PUR transmission, the WD 22 may receive an UL-Grant to schedule a retransmission. In dedicated-PUR, the UL-Grant may dynamically schedule the retransmission shortly (subject to availability of resources) after the unsuccessful transmission. For CFS-PUR based on MU-MIMO, the retransmission will be subject to the availability of resources, accounting for retransmitting along with other WDs 22 having the same transmission characteristics (e.g., using the same number of repetitions) so as to maintain orthogonality and avoid power imbalance. That is, the scheduled retransmissions for CFS-PUR based on MU-MIMO may be paired with other WDs 22 that are either transmitting or re-transmitting, but that have the same transmission characteristics.

In one embodiment, the network node 16, such as for example via the processing circuitry 68, will ensure that the cyclic shift of the WD 22 that will retransmit will not be the same cyclic shift that some other WD 22 will be using on the resources where the retransmission is to be performed, so as to maintain the DMRS orthogonality.

In one embodiment, the UL-Grant may contain updates to change the orthogonality with respect to what was used in the original transmission. For example, for eMTC, the UL grant may signal a new cyclic shift to the WD 22 that will retransmit, so as to avoid having the same cyclic shift that some other WD 22 will be using on the resources where the retransmission. This may be performed to maintain the DMRS orthogonality. Depending on whether 2, 4, or 8 cyclic DMRS shifts are used, either 1, 2, or 3 bits in DCI may be used. In other words, the WD 22 will use its regular cyclic DMRS shift as provided in the PUR configuration for any initial PUR transmission. Any HARQ retransmission switch to the DMRS shift (and possibly PUR RNTI) may be provided in the UL grant. In this way, the network node 16 has full flexibility to pair the re-transmitting WD 22 with other CFS-PUR WDs 22 any time within the remaining ‘PUR search space window’

It has been considered by the 3GPP that the WD 22 should be able to send, such as for example via the radio interface 82, a ‘PUR configuration request’ to the network node 16 in case the WD 22 wishes to be configured with PUR. As part of the CFS-PUR scheme it may also be beneficial if the WD 22 could indicate its preference to be configured with CFS-PUR. (An alternative solution involves the PUR configuration request configuring the WD 22 with CFS-PUR if the WD 22 is capable of CFS-PUR). In this case a 1-bit indication may be sufficient.

In case many CFS-PUR schemes are supported, e.g., both sub-PRB and MU-MIMO, the ‘PUR configuration request’, could include more information to inform the network node 16 as to which scheme the WD 22 prefers. A similar indication could be added to the signaling from the network node 16 to the WD 22, e.g., in a system information broadcast, to inform the WD 22 which CFS-PUR schemes are enabled in the cell served by the network node 16.

Although embodiments mainly address contention-free shared PUR (CFS-PUR), some of the embodiments are directly applicable to contention-based shared PUR (CBS). The only difference then may be that the WDs 22 have not received a WD 22 dedicated configuration, and collision with another WD 22 which has randomly selected the same parameters (e.g., cyclic DMRS shift, RNTI, etc.) may occur.

According to one aspect, a network node 16 is configured to communicate with a wireless device (WD 22). The network node 16 includes a radio interface 62 and/or comprising processing circuitry 68 configured to receive a preconfigured uplink resource (PUR) uplink transmission from the WD 22, and, responsive to receiving the PUR uplink transmission, transmit to the WD 22 an acknowledgement (ACK) at a time following a physical uplink shared channel (PUSCH) transmission so that the ACK arrives at the WD during a PUR search space window. According to this aspect, in some embodiments, the network node 16, including radio interface 62 and/or processing circuitry 68, is further configured to transmit to the WD 22 a starting point of the PUR search space window with respect to an end of the (N)PUSCH (or any physical uplink shared channel used for NR/NG-RAN) using contention free shared PURs (CFS-PUR). In some embodiments, the starting point of the PUR search space window is predetermined, via the processing circuitry 68, as a function of a cyclic shift and/or a WD 22 identification and/or radio network temporary identifier (RNTI) value using CFS-PUR. In some embodiments, the starting point of a physical downlink control channel (PDCCH) is with respect to an end of the (N)PUSCH (or any physical uplink shared channel used for NR/NG-RAN) transmission. In some embodiments, the network node, including the radio interface 62 and/or the processing circuitry 68, is further configured to configure different CFS-PUR WDs sharing a PUR resource with different radio network temporary identifier (RNTI) value. In some embodiments, the network node 16, including radio interface 62 and/or processing circuitry 68, is further configured to configure WDs transmitting simultaneously over CFS-PURs with a single PUR search space window. In some embodiments, the network node, including radio interface 62 and/or processing circuitry 68, is further configured to configure different WDs with different PUR search space windows. In some embodiments, the network node 16, including the radio interface 62 and/or processing circuitry 68 are further configured to multiplex multiple acknowledgements using WD offsets. In some embodiments, the network node 16, including radio interface 62 and/or processing circuitry 68, are further configured to pair transmissions or retransmissions intended for multiple WDs having a same power and/or number of repetitions.

According to another aspect, a method in a network node 16 includes receiving, via the radio interface 62, a preconfigured uplink resource (PUR) uplink transmission from the WD 22, and, responsive to receiving the PUR uplink transmission, transmitting via the radio interface 62 to the WD 22 an acknowledgement (ACK) at a time following a physical uplink shared channel (PUSCH) transmission so that the ACK arrives at the WD 22 during a PUR search space window.

According to this aspect, in some embodiments, the radio interface 62 is further configured to transmit to the WD 22 a starting point of the PUR search space window with respect to an end of the (N)PUSCH (or any physical uplink shared channel used for NR/NG- RAN) using contention free shared PURs (CFS-PUR). In some embodiments, the starting point of the PUR search space window is predetermined, via the processing circuitry 68, as a function of a cyclic shift and/or a WD 22 identification and/or radio network temporary identifier (RNTI) value using CFS-PUR. In some embodiments, the starting point of a physical downlink control channel (PDCCH) is with respect to an end of the (N)PUSCH (or any physical uplink shared channel used for NR/NG-RAN)transmission. In some embodiments, the method further includes configuring, via the processing circuitry 68. different CFS-PUR WDs sharing a PUR resource with different radio network temporary identifier (RNTI) value. In some embodiments, the method includes configuring WDs 22 transmitting simultaneously over CFS-PURs with a single PUR search space window. In some embodiments, the method includes configuring different WDs 22 with different PUR search space windows. In some embodiments, the method further comprises multiplexing via the processing circuitry 68 multiple acknowledgements using WD offsets. In some embodiments, the method further comprises pairing, via the radio interface 62 and/or processing circuitry 68, transmissions or retransmissions intended for multiple WDs 22 having a same power and/or number of repetitions.

According to another aspect, a wireless device (WD) 22 is configured to communicate with a network node 16. The WD 22 includes a radio interface 82 and/or processing circuitry 84 configured to transmit a preconfigured uplink resource (PUR) uplink transmission to the network node 16, and monitor, via the downlink channel monitor 34 a downlink channel from the network node 16 during a search space window for an acknowledgement (ACK) of receipt of the PUR uplink transmission, the monitoring beginning at a predetermined starting point after an end of a physical uplink shared channel (PUSCH) transmission by the WD.

According to this aspect, in some embodiments, the WD 22, including radio interface 82 and/or processing circuitry 84, is further configured to receive from the network node 16 a starting point of the PUR search space window with respect to an end of the (N)PUSCH (or any physical uplink shared channel used for NR/NG-RAN) using contention free shared PURs (CFS-PUR). In some embodiments, the radio WD 22, including radio interface 82 and/or processing circuitry 84, is configured to receive from the network node a PUR radio network temporary identifier (RNTI) and use the RNTI to determine if the ACK is intended for the WD. In some embodiments, the predetermined starting point is an offset based at least in part on a cyclic shift allocated to the WD by the network node.

According to another aspect, a method implemented in a wireless device (WD 22) includes transmitting, via the radio interface 82, a preconfigured uplink resource (PUR) uplink transmission to the network node 16, and monitoring, via the downlink channel monitor 34, a downlink channel from the network node 16 during a search space window for an acknowledgement (ACK) of receipt of the PUR uplink transmission, the monitoring beginning at a predetermined starting point after an end of a physical uplink shared channel (PUSCH) transmission by the WD.

According to this aspect, in some embodiments, the method further includes receiving, via the radio interface 82, from the network node 16 a starting point of the PUR search space window with respect to an end of the (N)PUSCH (or any physical uplink shared channel used for NR/NG-RAN) using contention free shared PURs (CFS-PUR). In some embodiments, the process further includes receiving from the network node 16 a PUR radio network temporary identifier (RNTI) and using the RNTI to determine if the ACK is intended for the WD 22. In some embodiments, the predetermined starting point is an offset based at least in part on a cyclic shift allocated to the WD 22 by the network node.

According to one aspect, a network node 16 is configured to communicate with a plurality of wireless devices, WD 22. The network node 16 comprises processing circuitry 68 configured to simultaneously receive a plurality of preconfigured uplink resource, PUR, uplink transmissions from a plurality of WDs 22 using contention free shared PUR, CFS- PUR and to transmit to the plurality of WDs 22 in downlink transmissions that include multiplexed responses to the PUR uplink transmissions.

According to this aspect, in some embodiments, the processing circuitry 68 is further configured to configure a WD 22 with a starting point of a PUR search space window with respect to an end of a physical uplink shared channel, (N)PUSCH (or any physical uplink shared channel used for NR/NG-RAN), using contention free shared PUR, CFS-PUR. In some embodiments, a starting point of the PUR search space window is predetermined as a function of a cyclic shift and/or a WD 22 identification and/or radio network temporary identifier, RNTI, value using CFS-PUR. In some embodiments, the processing circuitry 68 is further configured to configure different CFS-PUR WDs 22 sharing a PUR resource with different radio network temporary identifier, RNTI, values. In some embodiments, the processing circuitry 68 is further configured to configure WDs 22 transmitting simultaneously over contention free shared PUR, CFS-PUR with a single PUR search space window. In some embodiments, the processing circuitry 68 is further configured to configure different WDs 22 transmitting simultaneously over contention free shared PUR, CFS-PUR, with different PUR search space windows. In some embodiments, the processing circuitry 68 is further configured to multiplex multiple acknowledgements across downlink transmissions using WD 22 offsets. In some embodiments, the processing circuitry 68 is further configured to pair transmissions and/or retransmissions intended for multiple WDs 22 having a same power and/or number of repetitions. In some embodiments, the multiplexing of responses to the PUR uplink transmissions includes transmitting different responses to different WDs 22 on different beams. In some embodiments, the different responses transmitted to different WDs 22 are further distinguished by at least one of: a unique cyclic shift of a reference signal and a unique PUR radio network temporary identifier, RNTI. In some embodiments, different responses to different WDs 22 are distinguished by different cyclic shifts of a demodulation reference signal. In some embodiments, a sequence of cyclic shifts is used that is known to the different WDs 22. In some embodiments, different responses to the PUR uplink transmissions are transmitted on different frequencies. In some embodiments, radio network temporary identifiers, RNTIs, are used to distinguish downlink control information, DCI, messages used to schedule the responses to the PUR uplink transmissions on radio resource control, RRC, resources.

According to another aspect, a method implemented in a network node 16 in communication with a plurality of wireless devices, WDs 22, includes simultaneously receiving a plurality of preconfigured uplink resource, PUR, uplink transmissions from a plurality of WDs 22 using contention free shared PUR, CFS-PUR, and transmit to the plurality of WDs 22 in downlink transmissions that include multiplexed responses to the PUR uplink transmissions.

According to this aspect, in some embodiments, the method further includes configuring each of the plurality of WDs 22 with a starting point of a PUR search space window with respect to an end of a physical uplink shared channel, (N)PUSCH (or any physical uplink shared channel used for NR/NG-RAN) using contention free shared PURs, CFS-PUR. In some embodiments, the starting point of a PUR search space window is predetermined as a function of a cyclic shift and/or a WD 22 identification and/or radio network temporary identifier, RNTI, value using CFS-PUR. In some embodiments, the method also includes configuring different CFS-PUR WDs 22 sharing a PUR resource with different radio network temporary identifier, RNTI, values. In some embodiments, the method also includes configuring WDs 22 transmitting simultaneously over contention free shared, CFS, PURs with a single PUR search space window. In some embodiments, the method also includes configuring different WDs 22 transmitting simultaneously over CFS- PUR with different PUR search space windows. In some embodiments, the method also includes multiplexing across downlink transmissions multiple acknowledgements using WD 22 offsets. In some embodiments, the method also includes pairing transmissions or retransmissions intended for multiple WDs 22 having a same power and/or number of repetitions. In some embodiments, the multiplexing of responses to the PUR uplink transmissions includes transmitting different responses to different WDs 22 on different beams. In some embodiments, the different responses transmitted to different WDs 22 are further distinguished by at least one of a unique cyclic shift of a reference signal, and a unique PUR radio network temporary identifier, RNTI. In some embodiments, different responses to different WDs 22 are distinguished by different cyclic shifts of a demodulation reference signal. In some embodiments, a sequence of cyclic shifts is used that is known to the different WDs 22. In some embodiments, different responses to the PUR uplink transmissions are transmitted on different frequencies. In some embodiments, radio network temporary identifiers, RNTIs, are used to distinguish downlink control information, DCI, messages used to schedule the responses on radio resource control, RRC, resources.

According to yet another aspect, a WD 22 is configured to communicate with a network node 16. The WD 22 includes a radio interface 82 configured to transmit a preconfigured uplink resource, PUR, uplink transmission to the network node 16 and processing circuitry 84 configured to monitor a downlink channel from the network node 16 during a search space window for an acknowledgement, ACK, of receipt of the PUR uplink transmission.

According to this aspect, in some embodiments, the radio interface 82 is further configured to receive from the network node 16 a predetermined starting point of the search space window with respect to an end of a physical uplink shared channel, (N)PUSCH (or any physical uplink shared channel used for NR/NG-RAN) using contention free shared PURs, CFS-PUR. In some embodiments, the radio interface 82 is further configured to receive from the network node 16 a PUR radio network temporary identifier, RNTI, and use the RNTI to determine if the ACK is intended for the WD 22. In some embodiments, a predetermined starting point of the search space window is an offset based at least in part on a cyclic shift allocated to the WD 22 by the network node 16. In some embodiments, an ACK intended for the WD 22 is distinguished at least in part by a cyclic shift of a demodulation reference signal. In some embodiments, a sequence of cyclic shifts is used that is known to different WDs 22. In some embodiments, an ACK intended for the WD 22 is transmitted on a predetermined frequency assigned to the WD 22. In some embodiments, an ACK intended for the WD 22 is distinguished at least in part by a radio network temporary identifier, RNTI, indicative of a downlink control information, DCI, message used to schedule the ACK. According to another aspect, a method implemented in a wireless device, WD 22, includes transmitting a preconfigured uplink resource, PUR, uplink transmission to a network node 16, and monitoring a downlink channel from the network node 16 during a search space window for an acknowledgement, ACK, of receipt of the PUR uplink transmission.

According to this aspect, in some embodiments, the method also includes receiving from the network node 16 a starting point of the search space window with respect to an end of a physical uplink shared channel, (N)PUSCH (or any physical uplink shared channel used for NR/NG-RAN), using contention free shared PURs, CFS-PUR. In some embodiments, the method also includes receiving from the network node 16 a PUR radio network temporary identifier, RNTI, and using the RNTI to determine if the ACK is intended for the WD 22. In some embodiments, a predetermined starting point of the search space window is an offset based at least in part on a cyclic shift allocated to the WD 22 by the network node 16. In some embodiments, an ACK intended for the WD 22 is distinguished at least in part by a cyclic shift of a demodulation reference signal. In some embodiments, a sequence of cyclic shifts is used that is known to different WDs 22. In some embodiments, an ACK intended for the WD 22 is transmitted on a predetermined frequency assigned to the WD 22. In some embodiments, an ACK intended for the WD 22 is distinguished at least in part by a radio network temporary identifier, RNTI, indicative of a downlink control information, DCI, message used to schedule the ACK.

Some embodiments include the following:

Embodiment A1. A network node configured to communicate with a wireless device (WD), the network node configured to, and/or comprising a radio interface and/or comprising processing circuitry configured to: receive a preconfigured uplink resource (PUR) uplink transmission from the WD; and responsive to receiving the PUR uplink transmission, transmit to the WD an acknowledgement (ACK) at a time following a physical uplink shared channel (PUSCH) transmission so that the ACK arrives at the WD during a PUR search space window.

Embodiment A2. The network node of Embodiment Al, wherein the radio interface is further configured to transmit to the WD a starting point of the PUR search space window with respect to an end of the PUSCH using contention free shared PURs (CFS- PUR). Embodiment A3. The network node of Embodiment A2, wherein the starting point of the PUR search space window is predetermined as a function of a cyclic shift and/or a WD identification and/or radio network temporary identifier (RNTI) value using CFS-PUR.

Embodiment A4. The network node of Embodiment A2, wherein the starting point of a physical downlink control channel (PDCCH) is with respect to an end of the PUSCH transmission.

Embodiment A5. The network node of Embodiment Al, wherein the network node and/or the radio interface and/or the processing circuitry is further configured to configure different CFS-PUR WDs sharing a PUR resource with different radio network temporary identifier (RNTI) value.

Embodiment A6. The network node of Embodiment Al, wherein the network node and/or the radio interface and/or the processing circuitry is further configured to configure WDs transmitting simultaneously over CFS-PURs with a single PUR search space window.

Embodiment A7. The network node of Embodiment Al, wherein the network node and/or the radio interface and/or the processing circuitry is further configured to configure different WDs with different PUR search space windows.

Embodiment A8. The network node of Embodiment Al, wherein the network node and/or the radio interface and/or the processing circuitry is further configured to multiplex multiple acknowledgements using WD offsets.

Embodiment A9. The network node of Embodiment Al, wherein the network node and/or the radio interface and/or the processing circuitry is further configured to pair transmissions and/or retransmissions intended for multiple WDs having a same power and/or number of repetitions.

Embodiment B 1. A method implemented in a network node, the method comprising: receiving a preconfigured uplink resource (PUR) uplink transmission from the WD; and responsive to receiving the PUR uplink transmission, transmitting to the WD an acknowledgement (ACK) at a time following a physical uplink shared channel (PUSCH) transmission so that the ACK arrives at the WD during a PUR search space window.

Embodiment B2. The method of Embodiment B 1 , further includes transmitting to the WD a starting point of the PUR search space window with respect to an end of the PUSCH using contention free shared PURs (CFS-PUR).

Embodiment B3. The method of Embodiment B2, wherein the starting point of the PUR search space window is predetermined as a function of a cyclic shift and/or a WD identification and/or radio network temporary identifier (RNTI) value using CFS-PUR.

Embodiment B4. The method of Embodiment B2, wherein the starting point of a physical downlink control channel (PDCCH) is with respect to an end of the PUSCH transmission.

Embodiment B5. The method of Embodiment Bl, further comprising configuring different CFS-PUR WDs sharing a PUR resource with different radio network temporary identifier (RNTI) value.

Embodiment B6. The method of Embodiment Bl, further comprising configuring

WDs transmitting simultaneously over CFS-PURs with a single PUR search space window.

Embodiment B7. The method of Embodiment Bl, further comprising configuring different WDs with different PUR search space windows.

Embodiment B8. The method of Embodiment Bl, further comprising multiplexing multiple acknowledgements using WD offsets.

Embodiment B9. The method of Embodiment Bl, further comprising pairing transmissions or retransmissions intended for multiple WDs having a same power and/or number of repetitions. Embodiment Cl. A wireless device (WD) configured to communicate with a network node, the WD configured to, and/or comprising a radio interface and/or processing circuitry configured to: transmit a preconfigured uplink resource (PUR) uplink transmission to the network node; monitor a downlink channel from the network node during a search space window for an acknowledgement (ACK) of receipt of the PUR uplink transmission, the monitoring beginning at a predetermined starting point after an end of a physical uplink shared channel (PUSCH) transmission by the WD.

Embodiment C2. The WD of Embodiment Cl, wherein the WD and/or the radio interface and/or the processing circuitry is further configured to receive from the network node the predetermined starting point of the search space window with respect to the end of the PUSCH using contention free shared PURs (CFS-PUR).

Embodiment C3. The WD of Embodiment C2, wherein the WD and/or the radio interface and/or the processing circuitry is further configured to receive from the network node a PUR radio network temporary identifier (RNTI) and use the RNTI to determine if the ACK is intended for the WD.

Embodiment C4. The WD of Embodiment Cl, wherein the predetermined starting point is an offset based at least in part on a cyclic shift allocated to the WD by the network node.

Embodiment D1. A method implemented in a wireless device (WD), the method comprising: transmitting a preconfigured uplink resource (PUR) uplink transmission to a network node; monitoring a downlink channel from the network node during a search space window for an acknowledgement (ACK) of receipt of the PUR uplink transmission, the monitoring beginning at a predetermined starting point after an end of a physical uplink shared channel (PUSCH) transmission by the WD. Embodiment D2. The method of Embodiment Dl, further comprising receiving from the network node the starting point of the search space window with respect to the end of the PUSCH using contention free shared PURs (CFS-PUR).

Embodiment D3. The method of Embodiment D2, further comprising receiving from the network node a PUR radio network temporary identifier (RNTI) and using the RNTI to determine if the ACK is intended for the WD.

Embodiment D4. The method of Embodiment Dl, wherein the predetermined starting point is an offset based at least in part on a cyclic shift allocated to the WD by the network node.

As will be appreciated by one of skill in the art, the concepts described herein may be embodied as a method, data processing system, computer program product and/or computer storage media storing an executable computer program. Accordingly, the concepts described herein may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects all generally referred to herein as a “circuit” or “module.” Any process, step, action and/or functionality described herein may be performed by, and/or associated to, a corresponding module, which may be implemented in software and/or firmware and/or hardware. Furthermore, the disclosure may take the form of a computer program product on a tangible computer usable storage medium having computer program code embodied in the medium that can be executed by a computer. Any suitable tangible computer readable medium may be utilized including hard disks, CD-ROMs, electronic storage devices, optical storage devices, or magnetic storage devices.

Some embodiments are described herein with reference to flowchart illustrations and/or block diagrams of methods, systems and computer program products. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer (to thereby create a special purpose computer), special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer readable memory or storage medium that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture including instruction means which implement the function/act specified in the flowchart and/or block diagram block or blocks.

The computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks.

It is to be understood that the functions/acts noted in the blocks may occur out of the order noted in the operational illustrations. For example, two blocks shown in succession may in fact be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the functionality/acts involved. Although some of the diagrams include arrows on communication paths to show a primary direction of communication, it is to be understood that communication may occur in the opposite direction to the depicted arrows.

Computer program code for carrying out operations of the concepts described herein may be written in an object oriented programming language such as Java® or C++.

However, the computer program code for carrying out operations of the disclosure may also be written in conventional procedural programming languages, such as the "C" programming language. The program code may execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer. In the latter scenario, the remote computer may be connected to the user's computer through a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider). Many different embodiments have been disclosed herein, in connection with the above description and the drawings. It will be understood that it would be unduly repetitious and obfuscating to literally describe and illustrate every combination and subcombination of these embodiments. Accordingly, all embodiments can be combined in any way and/or combination, and the present specification, including the drawings, shall be construed to constitute a complete written description of all combinations and subcombinations of the embodiments described herein, and of the manner and process of making and using them, and shall support claims to any such combination or subcombination.

Abbreviations that may be used in the preceding description include: Abbreviation Explanation

3GPP 3rd Generation Partnership Project

ACK Acknowledge

CBS-PUR Contention Based Shared - Preconfigured Uplink Resources

CE Coverage Enhanced / Enhancement CFS-PUR Contention Free Shared - Preconfigured Uplink Resources

DCI Downlink Control Information

DL Downlink

EDT Early Data Transmission eMTC enhanced Machine-Type Communications eNB Evolved NodeB

IoT Internet of Things

LTE Long-Term Evolution

M2M Machine-to-Machine

MAC Medium-Access Control MPDCCH MTC Physical Downlink Control Channel

MTC Machine-Type Communications

NB-IoT Narrowband Internet of Things

NPDCCH Narrowband Physical Downlink Control Channel NPDSCH Narrowband Physical Downlink Shared Channel

NPUSCH Narrowband Physical Uplink Shared Channel

PDSCH Physical Downlink Shared Channel

PRB Physical Resource Block

PUR Preconfigured Uplink Resources

PUSCH Physical Uplink Shared Channel

RRC Radio Resource Control (protocol)

RU Resource Unit

TA Timing Advance

TBS Transport Block Size

UE User Equipment

UL Uplink

WI Work Item

It will be appreciated by persons skilled in the art that the embodiments described herein are not limited to what has been particularly shown and described herein above. In addition, unless mention was made above to the contrary, it should be noted that all of the accompanying drawings are not to scale. A variety of modifications and variations are possible in light of the above teachings without departing from the scope of the following claims.

Claims

What is claimed is:

1. A network node (16) configured to communicate with a plurality of wireless devices, WD (22), the network node (16) comprising processing circuitry (68) configured to: simultaneously receive a plurality of preconfigured uplink resource, PUR, uplink transmissions from a plurality of WDs (22) using contention free shared PUR, CFS-PUR; and transmit to the plurality of WDs (22) in downlink transmissions that include multiplexed responses to the PUR uplink transmissions.

2. The network node (16) of Claim 1, wherein the processing circuitry (68) is further configured to configure a WD (22) with a starting point of a PUR search space window with respect to an end of a physical uplink shared channel, using contention free shared PUR, CFS- PUR.

3. The network node (16) of Claim 2, wherein a starting point of the PUR search space window is predetermined as a function of a cyclic shift and/or a WD (22) identification and/or radio network temporary identifier, RNTI, value using CFS-PUR.

4. The network node (16) of any of Claims 1-3, wherein the processing circuitry (68) is further configured to configure different CFS-PUR WDs (22) sharing a PUR resource with different radio network temporary identifier, RNTI, values.

5. The network node (16) of any of Claims 1-4, wherein the processing circuitry (68) is further configured to configure WDs (22) transmitting simultaneously over contention free shared PUR, CFS-PUR with a single PUR search space window.

6. The network node (16) of any of Claims 1-5, wherein the processing circuitry (68) is further configured to configure different WDs (22) transmitting simultaneously over contention free shared PUR, CFS-PUR, with different PUR search space windows.

43

7. The network node (16) of any of Claims 1-6, wherein the processing circuitry (68) is further configured to multiplex multiple acknowledgements across downlink transmissions using WD (22) offsets.

8. The network node (16) of any of Claims 1-7, wherein the processing circuitry (68) is further configured to pair transmissions and/or retransmissions intended for multiple WDs (22) having a same power and/or number of repetitions.

9. The network node (16) of Claim 1, wherein the multiplexing of responses to the PUR uplink transmissions includes transmitting different responses to different WDs (22) on different beams.

10. The network node (16) of Claim 9, wherein the different responses transmitted to different WDs (22) are further distinguished by at least one of: a unique cyclic shift of a reference signal and a unique PUR radio network temporary identifier, RNTI.

11. The network node (16) of any of Claims 1-10, wherein different responses to different WDs (22) are distinguished by different cyclic shifts of a demodulation reference signal.

12. The network node (16) of Claim 11, wherein a sequence of cyclic shifts is used that is known to the different WDs (22).

13. The network node (16) of any of Claims 1-12, wherein different responses to the PUR uplink transmissions are transmitted on different frequencies.

14. The network node (16) of any of Claims 1-13, wherein radio network temporary identifiers, RNTIs, are used to distinguish downlink control information, DCI, messages used to schedule the responses to the PUR uplink transmissions on radio resource control, RRC, resources.

44

15. A method implemented in a network node (16) in communication with a plurality of wireless devices, WDs (22), the method comprising: simultaneously receiving (SI 34) a plurality of preconfigured uplink resource, PUR, uplink transmissions from a plurality of WDs (22) using contention free shared PUR, CFS-PUR; and transmit (S136) to the plurality of WDs (22) in downlink transmissions that include multiplexed responses to the PUR uplink transmissions.

16. The method of Claim 15, further comprising configuring each of the plurality of WDs (22) with a starting point of a PUR search space window with respect to an end of a physical uplink shared channel using contention free shared PURs, CFS-PUR.

17. The method of Claim 16, wherein the starting point of a PUR search space window is predetermined as a function of a cyclic shift and/or a WD (22) identification and/or radio network temporary identifier, RNTI, value using CFS-PUR.

18. The method of any of Claims 15-17, further comprising configuring different CFS-PUR WDs (22) sharing a PUR resource with different radio network temporary identifier, RNTI, values.

19. The method of any of Claims 15-18, further comprising configuring WDs (22) transmitting simultaneously over contention free shared, CFS, PURs with a single PUR search space window.

20. The method of any of Claims 15-19, further comprising configuring different WDs (22) transmitting simultaneously over CFS-PUR with different PUR search space windows.

21. The method of any of Claims 15-20, further comprising multiplexing across downlink transmissions multiple acknowledgements using WD (22) offsets.

45

22. The method of any of Claims 15-21, further comprising pairing transmissions or retransmissions intended for multiple WDs (22) having a same power and/or number of repetitions.

23. The method of Claim 15, wherein the multiplexing of responses to the PUR uplink transmissions includes transmitting different responses to different WDs (22) on different beams.

24. The method of Claim 23, wherein the different responses transmitted to different WDs (22) are further distinguished by at least one of a unique cyclic shift of a reference signal, and a unique PUR radio network temporary identifier, RNTI.

25. The method of any of Claims 15-24, wherein different responses to different WDs (22) are distinguished by different cyclic shifts of a demodulation reference signal.

26. The method of Claim 25, wherein a sequence of cyclic shifts is used that is known to the different WDs (22).

27. The method of any of Claims 15-26, wherein different responses to the PUR uplink transmissions are transmitted on different frequencies.

28. The method of any of Claims 15-27, wherein radio network temporary identifiers, RNTIs, are used to distinguish downlink control information, DCI, messages used to schedule the responses on radio resource control, RRC, resources.

29. A wireless device, WD (22), configured to communicate with a network node (16), the WD (22) comprising: a radio interface (82) configured to transmit a preconfigured uplink resource, PUR, uplink transmission to the network node (16); and

46 processing circuitry (84) configured to monitor a downlink channel from the network node (16) during a search space window for an acknowledgement, ACK, of receipt of the PUR uplink transmission.

30. The WD (22) of Claim 29, wherein the radio interface (82) is further configured to receive from the network node (16) a predetermined starting point of the search space window with respect to an end of a physical uplink shared channel using contention free shared PURs, CFS-PUR.

31. The WD (22) of Claim 30, wherein the radio interface (82) is further configured to receive from the network node (16) a PUR radio network temporary identifier, RNTI, and use the RNTI to determine if the ACK is intended for the WD (22).

32. The WD (22) of any of Claims 29-31, wherein a predetermined starting point of the search space window is an offset based at least in part on a cyclic shift allocated to the WD (22) by the network node (16).

33. The WD (22) of any of Claims 29-24, wherein an ACK intended for the WD (22) is distinguished at least in part by a cyclic shift of a demodulation reference signal.

34. The WD (22) of Claim 33, wherein a sequence of cyclic shifts is used that is known to different WDs (22).

35. The WD (22) of any of Claims 29-34, wherein an ACK intended for the WD (22) is transmitted on a predetermined frequency assigned to the WD (22).

36. The WD (22) of any of Claims 29-35, wherein an ACK intended for the WD (22) is distinguished at least in part by a radio network temporary identifier, RNTI, indicative of a downlink control information, DCI, message used to schedule the ACK.

37. A method implemented in a wireless device, WD (22), the method comprising:

47 transmitting (SI 38) a preconfigured uplink resource, PUR, uplink transmission to a network node (16); and monitoring (SI 40) a downlink channel from the network node (16) during a search space window for an acknowledgement, ACK, of receipt of the PUR uplink transmission.

38. The method of Claim 37, further comprising receiving from the network node (16) a starting point of the search space window with respect to an end of a physical uplink shared channel using contention free shared PURs, CFS-PUR.

39. The method of Claim 38, further comprising receiving from the network node (16) a PUR radio network temporary identifier, RNTI, and using the RNTI to determine if the ACK is intended for the WD (22).

40. The method of any of Claims 37-39, wherein a predetermined starting point of the search space window is an offset based at least in part on a cyclic shift allocated to the WD (22) by the network node (16).

41. The method of any of Claims 37-40, wherein an ACK intended for the WD (22) is distinguished at least in part by a cyclic shift of a demodulation reference signal.

42. The method of Claim 41, wherein a sequence of cyclic shifts is used that is known to different WDs (22).

43. The method of any of Claims 37-42, wherein an ACK intended for the WD (22) is transmitted on a predetermined frequency assigned to the WD (22).

44. The method of any of Claims 37-43, wherein an ACK intended for the WD (22) is distinguished at least in part by a radio network temporary identifier, RNTI, indicative of a downlink control information, DCI, message used to schedule the ACK.

48