RADIO NETWORK NODE, USER EQUIPMENT AND METHODS PERFORMED

THEREIN

TECHNICAL FIELD

Embodiments herein relate to a radio network node, a user equipment (UE) and methods performed therein regarding wireless communication. Furthermore, a computer program and a computer readable storage medium are also provided herein. In particular, embodiments herein relate to handling communication, such as handling or controlling measurements, in a wireless communications network.

BACKGROUND

In a typical wireless communications network, UEs, also known as wireless communication devices, mobile stations, stations (STA) and/or wireless devices, communicate via a Radio Access Network (RAN) with one or more core networks (CN). The RAN covers a geographical area which is divided into service areas or cells, with each service area or cell being served by a radio network node such as an access node, e.g., a Wi-Fi access point or a radio base station (RBS), which in some networks may also be called, for example, a NodeB, a gNodeB, or an eNodeB. The service area or cell is a geographical area where radio coverage is provided by the radio network node. The radio network node operates on radio frequencies to communicate over an air interface with the UEs within range of the radio network node. The radio network node communicates over a downlink (DL) to the UE and the UE communicates over an uplink (UL) to the radio network node.

A Universal Mobile Telecommunications System (UMTS) is a third generation (3G) telecommunication network, which evolved from the second generation (2G) Global System for Mobile Communications (GSM). The UMTS terrestrial radio access network (UTRAN) is essentially a RAN using wideband code division multiple access (WCDMA) and/or High-Speed Packet Access (HSPA) for communication with user equipment. In a forum known as the Third Generation Partnership Project (3GPP), telecommunications suppliers propose and agree upon standards for present and future generation networks and investigate e.g. enhanced data rate and radio capacity. In some RANs, e.g. as in UMTS, several radio network nodes may be connected, e.g., by landlines or microwave, to a controller node, such as a radio network controller (RNC) or a base station controller (BSC), which supervises and coordinates various activities of the plural radio network nodes connected thereto. The RNCs are typically connected to one or more core networks.

Specifications for the Evolved Packet System (EPS) have been completed within the 3GPP and other 3GPP releases, such as New Radio (NR), are worked on. The EPS comprises the Evolved Universal Terrestrial Radio Access Network (E-UTRAN), also known as the Long-Term Evolution (LTE) radio access network, and the Evolved Packet Core (EPC), also known as System Architecture Evolution (SAE) core network. E- UTRAN/LTE is a 3GPP radio access technology wherein the radio network nodes are directly connected to the EPC core network. As such, the Radio Access Network (RAN) of an EPS has an essentially “flat” architecture comprising radio network nodes connected directly to one or more core networks.

With the emerging 5G technologies such as NR, the use of very many transmit- and receive-antenna elements may be of great interest as it makes it possible to utilize beamforming, such as transmit-side and receive-side beamforming. Transmit-side beamforming means that the transmitter can amplify the transmitted signals in a selected direction or directions, while suppressing the transmitted signals in other directions. Similarly, on the receive-side, a receiver can amplify signals from a selected direction or directions, while suppressing unwanted signals from other directions.

The current 5G RAN (NG-RAN) architecture is depicted and described in TS 38.401 v15.4.0 (http://www.3gpp.Org/ftp//Specs/archive/38_series/38.401/384 01-f40.zip) , see Fig. 1.

The next generation (NG)-RAN architecture can be further described as follows. The NG-RAN consists of a set of gNBs connected to the 5GC through the NG interface. An gNB can support frequency division duplex (FDD) mode, time division duplex (TDD) mode or dual mode operation. gNBs can be interconnected through the Xn interface. A gNB may consist of a gNB-central unit (CU) and gNB-distributed units (DU). A gNB-CU and a gNB-DU are connected via the F1 logical interface. By specification, one gNB-DU is connected to only one gNB-CU. However, for resiliency, a gNB-DU may be connected to multiple gNB-CUs by appropriate implementation. NG, Xn and F1 are logical interfaces. The NG-RAN is layered into a Radio Network Layer (RNL) and a Transport Network Layer (TNL). The NG-RAN architecture, i.e., the NG-RAN logical nodes and interfaces between them, is defined as part of the RNL. For each NG-RAN interface (NG, Xn, F1) the related TNL protocol and the functionality are specified. The TNL provides services for user plane transport and signalling transport. A gNB may also be connected to an LTE eNB via the X2 interface. Another architectural option is that where an LTE eNB connected to the EPC network is connected over the X2 interface with a so called nr-gNB. The latter is a gNB not connected directly to a CN and connected via X2 to an eNB for the sole purpose of performing dual connectivity.

The architecture in Fig. 1 can be expanded by splitting the gNB-Cll into two entities: One gNB-CU-user plane (UP), which serves the user plane and hosts the packet data convergence protocol (PDCP) protocol and one gNB-CU-control plane (CP), which serves the control plane and hosts the PDCP and radio resource control (RRC) protocol. A gNB-CU-CP and a gNB-CU-UP communicate over the E1 interface. For completeness it should be said that a gNB-DU hosts the radio link control (RLC), media access control (MAC) and physical (PHY) protocols.

NR in shared, unlicensed, spectrum.

The 5 ^th generation of cellular system, called NR, is developed for maximum flexibility to support multiple and substantially different use cases. Besides the typical mobile broadband use case, also machine type communication (MTC), ultra-reliable low- latency communication (URLLC), side-link device-to-device (D2D) and several other use cases too.

In NR, the basic scheduling unit is called a slot. A slot consists of 14 orthogonal frequency division multiplexing (OFDM) symbols for the normal cyclic prefix configuration. NR supports many different subcarrier spacing configurations and at a subcarrier spacing of 30 kHz the OFDM symbol duration is ~33 ps. As an example, a slot with 14 symbols for the same subcarrier spacing (SOS) is 500 ps long, including cyclic prefixes.

NR also supports flexible bandwidth configurations for different UEs on the same serving cell. In other words, the bandwidth monitored by a UE and used for its control and data channels may be smaller than the carrier bandwidth. One or multiple bandwidth part configurations for each component carrier can be semi-statically signalled to a UE, where a bandwidth part consists of a group of contiguous physical resource blocks (PRB). Reserved resources can be configured within the bandwidth part. The bandwidth of a bandwidth part equals to or is smaller than the maximal bandwidth capability supported by a UE.

NR is targeting both licensed and unlicensed spectrum bands and a work item named NR-based Access to Unlicensed Spectrum (NR-U) was started in January 2019. Allowing unlicensed networks, i.e., networks that operate in shared spectrum, i.e., unlicensed spectrum, to effectively use the available spectrum is an attractive approach to increase system capacity. Although unlicensed spectrum does not match the qualities of the licensed regime, solutions that allow an efficient use of it as a complement to licensed deployments have the potential to bring great value to the 3GPP operators, and, ultimately, to the 3GPP industry as a whole. Some NR features are adapted in NR-ll to comply with the special characteristics of the unlicensed band as well as different regulations. The technology primarily targets subcarrier spacings of 15 kHz or 30 kHz in carrier frequencies below 6 GHz.

When operating in unlicensed spectrum, many regions in the world require a device to sense the medium to check that it is free before transmitting. This operation is often referred to as listen before talk or LBT for short, while a more formal term is Clear Channel Assessment (CCA). There are many different flavors of LBT, depending on which radio technology the device uses and which type of data the device wants to transmit at the moment. Common for all flavors is that the sensing is done in a particular channel, corresponding to a defined carrier frequency, and over a predefined bandwidth. For example, in the 5 GHz band, the sensing is done over 20 MHz channels and this is also the sensing bandwidth used in NR-ll, where such 20 MHz bandwidths/channels are often referred to as bandwidth parts (BWP), when the full NR-ll operating bandwidth is greater than 20 MHz.

Many devices are capable of transmitting, and receiving, over a wide bandwidth including of multiple sub-bands/channels, e.g., multiple LBT sub-bands, i.e. , the frequency part with a bandwidth equal to LBT bandwidth. A device is only allowed to transmit on the sub-bands, i.e., 20 MHz BWPs, where the medium is sensed as free. Again, there are different flavours of how the sensing should be done when multiple sub-bands are involved.

In principle, there are two ways a device can operate over multiple sub-bands. One way is that the transmitter/receiver bandwidth is changed depending on which subbands were sensed as free. In this setup, there is only one component carrier (CC) and the multiple sub-bands are treated as single channel with a larger bandwidth. The other way is that the device operates almost independent processing chains for each channel. Depending on how independent the processing chains are, this option can be referred to as either carrier aggregation (CA) or dual connectivity (DC). Channel access procedure in NR unlicensed spectrum

LBT is designed for unlicensed spectrum co-existence with other radio access technologies (RAT), as well as independent systems with the same RAT. In this mechanism, a radio device applies a CCA check, i.e., channel sensing before any transmission. The transmitter involves energy detection (ED) over a time period compared to a certain threshold, also referred to as ED threshold, in order to determine if a channel is idle.

LBT parameter settings, including ED threshold, may be set for devices in a network by a network node configuring the devices in the network. The limits may be set as pre-defined rules or tables in specifications or regulatory requirements for operation in a certain region. Such limits are part of the ETSI harmonized standard in Europe as well as the 3GPP specification for operation of LTE- License Assisted Access (LAA) I NR-ll in unlicensed spectrum.

Further, two modes of access operations are defined - Frame-Based Equipment (FBE) and Load-Based Equipment (LBE). In FBE mode, the sensing period is simple, while the sensing scheme in LBE mode is more complex.

For quality of service (QoS) differentiation, a channel access priority classes (CAPC) based on the service type quality class identifier (QCI) and/or 5G QoS Identifier (5QI) has been defined for the channel access. For example, there are four LBT priority classes that are defined, so that depending on the priority of the data to transmit, the UE needs to perform different channel sensing procedures. That is to allow a fair coexistence in the wireless medium of different types of traffic so that higher priority traffic can have higher chances to access the channel.

Dynamic channel occupancy in LBE mode.

The default LBT mechanism for LBE operation, LBT category 4, is similar to existing Wi-Fi operation, where a node can sense the channel at any time and start transmitting if the channel is free after a deferral and backoff period. For specific cases, e.g., shared channel occupancy time (COT), other LBT categories allow a very short sensing period.

Sensing is done typically for a random number of sensing intervals with this random number being a number within the range of 0 to contention window (CW), where CW represents a contention window size. Initially, a backoff counter is initialized to this random number drawn within 0 and CW. When a busy carrier is sensed to have become idle, a device must wait for a fixed period also known as a prioritization period, after which it can sense the carrier in units of the sensing interval. For each sensing interval within which the carrier is sensed to be idle, the backoff counter is decremented. When the backoff counter reaches zero, the device can transmit on the carrier. After transmission, if a collision is detected via the reception of a negative acknowledgement or by some other means, the contention window size (CWS) is doubled. As soon as the transmitter has grasped access to a channel, the transmitter is only allowed to perform transmission up to a maximum time duration, namely, the maximum channel occupancy time (MCOT). For QoS differentiation, a channel access priority based on the service type has been defined. For example, there are four LBT priority classes that are defined for differentiation of contention window sizes and MCOT between services.

Semi-static channel occupancy in FBE mode.

In FBE mode as defined in 3GPP and illustrated in Fig. 2, the gNB assigns Fixed Frame Periods (FFP), senses the channel for 9 ps just before the FFP boundary, and if the channel is sensed to be free, it starts with a downlink transmission, and/or allocates resources among different UEs in the FFP. This procedure can be repeated with a certain periodicity. In the FFP, DL/LIL transmissions are only allowed within the COT, a subset of FFP resource, where the remaining Idle period is reserved so that other nodes also have the chance to sense and utilize the channel. Hence in FBE operations, the channel is sensed at specific intervals just before the FFP boundary. The FFP can be set to values between 1 and 10 ms and can be changed after a minimum of 200 ms. The IDLE period is a regulatory requirement and is supposed to be at least TIDLE S max(0.05*COT, 100 ps). In 3GPP TS 37.213 v.16.0.0 this has been simplified to be TIDLE S max(0.05*FFP, 100 ps), i.e. the maximum channel occupancy time, MCOT, would be defined as TMCOT = min(0.95*FFP, FFP-0.1ms). So for 10 ms FFP, the MCOT would be 9.5 ms, while for 1 ms FFP the MCOT would be 0.9 ms = 0.9*FFP.

SUMMARY

As part of developing embodiments herein one or more problems were first identified.

Layer 2 (L2) measurements.

L2 measurements are performed per data radio bearer (DRB) and are divided into L2 measurements performed by the gNB and L2 measurements performed by the UE. Possible L2 measurement include:

• Received Random Access Preambles

• Packet delay

• Number of active UEs in RRC_CONNECTED

• Number of stored inactive UE contexts

• Packet Loss Rate

• PRB Usage Related to packet delay, the L2 measurements of packet delays performed by the gNB can further divide into DL-related packet measurements and UL-related packet measurement which include also the delay experienced at the UE side.

More specifically, as stated in 3GPP TS 38.314 v.16.0.0, the RAN part of DL packet delay measurement comprises:

D1 (DL delay in over-the-air interface), referring to Average delay DL airinterface in TS 28.552 v.17.6.0.

D2 (DL delay on gNB-DU), referring to Average delay in RLC sublayer of gNB-DU in TS 28.552.

D3 (DL delay on F1-U), referring to Average delay on F1-U in TS 28.552 [2].

D4 (DL delay in CU-UP), referring to Average delay DL in CU-UP in TS 28.552.

The DL packet delay measurements, i.e. , D1 (the DL delay in over-the-air interface), D2 (the DL delay in gNB-DU), D3 (the DL delay on F1-U) and D4 (the DL delay in CU-UP), should be measured per DRB per UE.

On the other hand, for the UL, the RAN part (including UE) of UL packet delay measurement comprises:

D1 (UL PDCP packet average delay).

D2.1 (average over-the-air interface packet delay).

D2.2 (average RLC packet delay).

D2.3 (average delay UL on F1-U, it is measured using the same metric as the average delay DL on F1-U defined in TS 28.552).

D2.4 (average PDCP re-ordering delay).

Current L2 measurement framework definition for packet delay measurements does not consider the impact of LBT. Hence by just considering the current packet delay measurements, it will not be possible to isolate the contribution to the delay of the LBT. This is not desirable from a network optimization perspective, because it will not be possible to evaluate and possibly optimize the system performances in unlicensed spectrum.

Additionally, the LBT issues may also affect the scheduling delays because also the scheduling request (SR) may be subject to LBT failures before being transmitted over the air interface. Similarly, also the uplink grant, allocating uplink transmission resources, transmitted by the gNB may be subject to LBT failures and hence it may be delayed. Other signalling may also be affected. For example, once the buffer status report (BSR) is triggered at the MAC layer, the UE will include the buffer size in the BSR MAC control element (CE) as measured when the BSR is triggered. However, the transmission of the BSR may be postponed at physical layer due to LBT issues, and it may be eventually transmitted at a later point in time at another scheduling occasion. Hence, when the BSR is finally transmitted, the actual UE buffer status may be different, e.g., it may have increased. The network obviously does not know that, and it may provide an uplink grant which is for a smaller amount of data than what the UE needs.

Thus, measurements may not be correct leading to a non-optimized handling of communication in the wireless communications network.

An object herein is to provide a mechanism to handle measurements of a UE in an efficient manner in the wireless communications network.

According to an aspect the object is achieved, according to embodiments herein, by providing a method performed by a UE for handling measurements in a wireless communications network. The UE performs a measurement of a parameter related to an LBT delay when accessing a channel. For example, the UE may measure a LBT delay, number of LBT failures, or a measurement that is affected by the LBT delay, or similar.

According to an aspect the object is achieved, according to embodiments herein, by providing a method performed by a radio network node for handling communication in a wireless communications network. The radio network node may obtain an indication of a measured parameter related to an LBT delay of a UE accessing a channel and/or a measurement related to the LBT delay, i.e. , a measurement affected by the measured parameter. The radio network node may receive the indication or the measurement, or measure the parameter or perform the measurement.

According to an aspect the object is achieved, according to embodiments herein, by providing a UE and a radio network node configured to perform the methods herein, respectively.

Thus, a UE for handling measurements in a wireless communications network. The UE is configured to perform a measurement of a parameter related to an LBT delay when accessing a channel.

A radio network node for handling communication in a wireless communications network. The radio network node is configured to obtain an indication of a measured parameter related to an LBT delay of a UE accessing a channel and/or a measurement related to the LBT delay, i.e., a measurement affected by the measured parameter. It is furthermore provided herein a computer program product comprising instructions, which, when executed on at least one processor, cause the at least one processor to carry out the methods herein, as performed by the UE or the radio network node, respectively. It is additionally provided herein a computer-readable storage medium, having stored thereon a computer program product comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the method according to the methods herein, as performed by the UE or the radio network node, respectively.

The proposed solution allows the radio network node to better evaluate and possibly optimize the system performance when operating in shared spectrum.

Thus, the obtained parameter and/or measurement indicates the LBT delay or the effect of the LBT delay that may be used to optimize performance or similar at the wireless communications network.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will now be described in more detail in relation to the enclosed drawings, in which:

Fig. 1 shows a scenario according to prior art;

Fig. 2 shows a scenario according to prior art;

Fig. 3 shows an overview depicting a wireless communications network according to embodiments herein;

Fig. 4 shows a combined signalling scheme and flowchart depicting embodiments herein;

Fig. 5 shows a flowchart depicting a method performed by a UE according to embodiments herein;

Fig. 6 shows a flowchart depicting a method performed by a radio network node according to embodiments herein;

Fig. 7 shows a schematic overview depicting some embodiments herein;

Fig. 8 shows a block diagram depicting embodiments of a UE according to embodiments herein;

Fig. 9 shows a block diagram depicting embodiments of a radio network node according to embodiments herein;

Fig. 10 schematically illustrates a telecommunication network connected via an intermediate network to a host computer; Fig. 11 is a generalized block diagram of a host computer communicating via a base station with a user equipment over a partially wireless connection; and

Figs. 12,13,14,15 are flowcharts illustrating methods implemented in a communication system including a host computer, a base station and a user equipment.

DETAILED DESCRIPTION

Embodiments herein relate to wireless communications networks in general. Fig. 3 is a schematic overview depicting a wireless communications network 1. The wireless communications network 1 comprises one or more RANs and one or more CNs. The wireless communications network 1 may use one or a number of different technologies. Embodiments herein relate to recent technology trends that are of particular interest in a NR context, however, embodiments are also applicable in further development of existing wireless communications systems such as e.g. LTE or Wideband Code Division Multiple Access (WCDMA).

In the wireless communications network 1, a user equipment (UE) 10 exemplified herein as a wireless device such as a mobile station, a non-access point (non-AP) station (STA), a STA and/or a wireless terminal, is comprised communicating via e.g. one or more Access Networks (AN), e.g. radio access network (RAN), to one or more core networks (CN). It should be understood by the skilled in the art that “UE” is a non-limiting term which means any terminal, wireless communications terminal, user equipment, narrowband internet of things (NB-loT) device, Machine Type Communication (MTC) device, Device to Device (D2D) terminal, or node e.g. smart phone, laptop, mobile phone, sensor, relay, mobile tablets or even a small base station capable of communicating using radio communication with a radio network node within an area served by the radio network node.

The wireless communications network 1 comprises a radio network node 12 providing radio coverage over a geographical area, a first service area 11 or first cell, of a first radio access technology (RAT), such as NR, LTE, or similar. The radio network node 12 may be a transmission and reception point such as an access node, an access controller, a base station, e.g. a radio base station such as a gNodeB (gNB), an evolved Node B (eNB, eNode B), a NodeB, a base transceiver station, a radio remote unit, an Access Point Base Station, a base station router, a Wireless Local Area Network (WLAN) access point or an Access Point Station (AP STA), a transmission arrangement of a radio base station, a stand-alone access point or any other network unit or node capable of communicating with a wireless device within the area served by the radio network node depending e.g. on the first radio access technology and terminology used. The radio network node 12 may be referred to as a serving radio network node wherein the service area may be referred to as a serving cell, and the serving radio network node communicates with the UE in form of DL transmissions to the UE 10 and UL transmissions from the UE 10. It should be noted that a service area may be denoted as cell, beam, beam group or similar to define an area of radio coverage.

According to embodiments herein, the UE 10 is configured, either preconfigured or configured by the radio network node 12, to measure a parameter related to an LBT delay when accessing a channel. A parameter related to an LBT delay may be any parameter that is affected by the LBT delay. The UE 10 may further transmit an indication of the measured parameter. The proposed solution allows the radio network node 12 to better evaluate and possibly optimize the system performance when operating in shared spectrum. For example, the radio network node 12 may classify on the basis of the impacts on packet transmission delays, or scheduling delays how severe is the impact of LBT in the system performances in a given carrier. If it is determined that LBT has a major impact, the radio network node 12 may reduce the load in the specific shared carrier and move the traffic in a less loaded shared carrier or in a licensed carrier.

Fig. 4 is a combined signalling scheme and flowchart according to embodiments herein.

Action 401. The radio network node 12 may transmit configuration data to the UE 10 for configuring the UE 10 to perform methods herein. It should be noted that the radio network node 12 may request the UE 10 to report any measurement, e.g., the average PDCP delay, and then the UE considers the LBT delay when it calculates this legacy measurement.

Action 402. The UE 10 performs a measurement of a parameter related to an LBT delay when accessing a channel. For example, the UE may measure a LBT delay, number of LBT failure or similar. The UE 10 may perform any measurement such as DL- related packet measurements and/or UL-related packet measurement that is affected by the LBT delay.

Action 403. The UE 10 may then transmit to the radio network node 12, an indication such as a value or an index of the measured parameter, or the measurement affected by the LBT delay.

Action 404. The radio network node 12 may then trigger an action based on the received indication. For example, the radio network node 12 may reduce the load in a specific shared carrier and move the traffic in a less loaded shared carrier or in a licensed carrier.

The method actions performed by the UE 10 for handling measurements in the wireless communications network according to embodiments will now be described with reference to a flowchart depicted in Fig. 5. The actions do not have to be taken in the order stated below, but may be taken in any suitable order. Dashed boxes indicate optional features.

Action 501. The UE 10 may receive configuration data from the radio network node 12 for configuring the UE 10 to perform methods herein.

Action 502. The UE 10 then performs the measurement of the parameter related to the LBT delay when accessing a channel. For example, the UE 10 may measure a LBT delay, and/or count a number of LBT failures or similar. The UE 10 may perform any measurement such as DL-related packet measurements and/or UL-related packet measurement that is affected by the LBT delay. The performed measurement may comprise one or more of the following: a packet data convergence protocol (PDCP) average delay in the UL per DRB; a point in time when a uplink medium access control protocol data unit (UL MAC PDU) including a first part of an uplink packet data convergence protocol service data unit (UL PDCP SDU) is transmitted over an air interface; a time elapsed between triggering a scheduling request (SR) and receiving a scheduling grant; a time elapsed between triggering a Buffer Status Report (BSR) at a MAC layer and transmitting the BSR in a buffer status report medium access control control element (BSR MAC CE) over an air interface at a physical layer; a difference between a buffer size included in a triggered BSR MAC CE and a buffer size of the UE at the time of the transmission over an air interface of the BSR MAC CE; deducting a cumulative LBT delay occurred during a time period during which a L2 measurement is performed and use the resulting time period minus the cumulative LBT delay to calculate the L2 measurement. The performed measurement may be affected by the LBT delay and/or consider an impact of the LBT delay in computation.

The measurement may be performed for each DRB for each CAPC; or for each CAPC within each DRB; or separately per shared spectrum channel bandwidth, or per shared spectrum operating band. The performed measurement may take into account an impact of channel access procedure type and/or time division duplex (TDD) pattern. Action 503. The UE 10 may store/log the measured parameter at the UE 10 and/or a measurement related to the measured parameter, for example, measurement affected by the LBT delay.

Action 504. The UE 10 may then transmit or report, to the radio network node 12, an indication such as a value or an index of the measured parameter and/or a measurement related to a LBT delay, i.e. , a measurement affected by the LBT delay or affected by the measured parameter.

The method actions performed by the radio network node 12 for handling communication in the wireless communications network according to embodiments will now be described with reference to a flowchart depicted in Fig. 6. The actions do not have to be taken in the order stated below, but may be taken in any suitable order. Dashed boxes indicate optional features.

Action 601. The radio network node 12 may configure the UE 10 to log the measurement associated with the LBT delay. It should be noted that the radio network node 12 may request the UE 10 to report any measurement, e.g., the average PDCP delay, and then the UE considers the LBT delay when it calculates this legacy measurement.

Action 602. The radio network node 12 obtains the indication of the measurement of the parameter related to the LBT delay of the UE 10 when accessing the channel; and/or a measurement related to a LBT delay i.e., a measurement affected by, or associated with, the measured parameter. The indication may be a measured value or an index indicating the measured value. The measurement may be any measurement such as DL-related packet measurements and/or UL-related packet measurement that is affected by the LBT delay. The indication and/or the measurement may be received from the UE 10 and/or measured at the radio network node 12. The indication and/or the measurement may comprise one or more of the following: the PDCP average delay in the UL per DRB; the point in time when the UL MAC PDU including the first part of the UL PDCP SDU is transmitted over the air interface; the time elapsed between triggering the SR, and receiving the scheduling grant; the time elapsed between triggering the BSR at the MAC layer and transmitting the BSR in the BSR MAC CE over the air interface at the physical layer; the difference between the buffer size included in the triggered BSR MAC CE and the buffer size of the UE at the time of the transmission over the air interface of the BSR MAC CE; deducting the cumulative LBT delay occurred during the time period during which a L2 measurement is performed and use the resulting time period minus the cumulative LBT delay to calculate the L2 measurement. The indication and/or the measurement may be affected by the LBT delay and/or consider an impact of the LBT delay in computation.

The indication and/or the measurement may comprise a measured LBT delay and/or a counted number of LBT failures. The indication and/or the measurement may be for each DRB for each CAPC; for each CAPC within each DRB; separately per shared spectrum channel bandwidth, or per shared spectrum operating band.

Action 603. The radio network node 12 may then trigger an action based on the obtained indication and/or the measurement. For example, the radio network node 12 may reduce a load in a specific shared carrier and move the traffic to a less loaded shared carrier or to a licensed carrier. For example, the radio network node 12 may estimate performance taking the indication and/or the measurement into account.

Below are examples of the parameter measured.

The measurements performed in the following embodiment may be computed separately for each DRB, or for each CAPC, or for each CAPC within each DRB, or considering the band or the channel bandwidth used for shared spectrum.

Embodiments herein comprise, for example, a method in which the UE 10 or the radio network node 12, such as a gNB, may measure the “LBT delay” experienced by the UE 10 or the radio network node 12for transmitting a PDCP SDU. The “LBT delay” may be measured at physical layer as the time elapsed between the reception of a transport block (TB), including one or more parts of the PDCP SDU, from MAC layer and the transmission over the air interface of the TB or until the time the channel is declared busy, upon which the TB transmission does not occur.

For example, considering the definition of PDCP packet delay in TS 38.314 v.16.0.0 the following changes in italic and bold may represent such an embodiment. In particular in this example, it is considered that the LBT delay is computed as the time difference between the point in time when the UL MAC protocol data unit (PDU) k including the first part of UL PDCP SDU i is transmitted over the air-interface and the point in time in which this UL MAC PDU k is scheduled for transmission:

In bold and italic below, examples of the changes are shown with respect to the current legacy text.

In a variant of the above, the LBTDelay(i, drbid) may be defined as the time from the start (or end) of the first LBT procedure to the start, or end, of the successful LBT procedure which precedes the, delayed, transmission. This time is thus zero if the LBT succeeds for the first transmission attempt.

In another example, it is considered that the tDeliv(i) includes the LBT delay experienced by the MAC PDU:

In another variant, the measurement may be the delay experienced until the first over the air transmission, this transmissions may fail and there might be a retransmission but such a retransmission is not part of this measurement, after the LBT procedure while attempting to transmit a MAC PDU and such a measurement may be defined as follows:

In yet another variant, the measurement may be the delay experienced until the first over the air successful transmission after the LBT procedure while attempting to transmit a MAC PDU, this may include delay due to the retransmissions, and such a measurement may be defined as follows:

It should be noted that rather than per DRB ID as in the above examples, the above measurement may be taken per CAPC of the packets to be transmitted.

In another example, considering the definition for UL PDCP Packet Average Delay per DRB per UE in 38.314 v.16.0.0, this may be modified to consider the LBT delay.

The referenced table 4.3.1.1-2 could become:

Table 4.3.1.1-2: Parameter description for UL PDCP Packet Average Delay per

DRB per UE Similarly to the other example, rather than per DRB ID, the above measurement may be taken per CAPC of the packets to be transmitted. Similarly to the other example, the above measurement may be taken into consideration of the bandwidth used to transmit the packets, when operating in shared spectrum, e.g., 10 MHz, 20 MHz, 40 MHz, 60 MHz, 80 MHz.

In a method dependent on the previous methods, the UE takes into account only the slots in which the UE is scheduled for transmission. For example, in the computation of the delay for an UL MAC PDU k, the UE 10 does not consider the slots in which the UE 10 is not scheduled for transmission of the UL MAC PDU, e.g., in case of TDD the UE 10 does consider in the computation of the delay the slots that are not for UL transmissions. Cumulative LBT delay.

The UE 10 and/or the radio network node 12 may measure a cumulative LBT delay experienced by the UE 10 and/or the radio network node 12 for transmitting a PDCP SDU. The cumulative LBT delay is the sum of all the LBT delay experienced by the UE 10 for each of the TB including the parts of the PDCP SDU and measured over multiple scheduling occasions before the PDCP SDU is transmitted over the air interface.

The cumulative LBT delay may then consider all the PDCP SDUs of a certain DRB and/or CAPC, i.e. , for all the TBs containing such PDCP SDUs, transmitted by the UE 10 over certain time window, e.g. as in the following formula: Number of LBT failures per PDCP SDU.

The UE 10 and/or the radio network node 12 may measure the number of LBT failures experienced by the UE 10 for a PDCP SDU before transmitting it entirely, i.e., all the parts of the PDCP SDU, over the air interface. The number of LBT failures is measured as the number of TBs whose transmission was not performed due to LBT failure, i.e., channel sensed busy by the LBT procedure, and that included at least one part of the PDCP SDU. The number of LBT failures may be averaged over a certain time window for all the PDCP SDU of a certain DRB and/or CAPC, and/or channel bandwidth. Alternatively, a sliding average may be used, or an exponential average.

SR LBT delay.

The UE 10 may measure a SR LBT Delay, i.e., the time elapsed between triggering the SR and receiving a scheduling grant, wherein this time comprises the time elapsed between triggering the SR, as indicated by the MAC layer, and transmitting the SR over the air interface at the physical layer. In a variant, a SRLBT Delay may be defined as the time from the start, or end, of the first LBT procedure to the start, or end, of the successful LBT procedure which precedes the, delayed, transmission. This time is thus zero if the LBT succeeds for the first transmission attempt.

An example of such a measurement is defined as follows.

BSR LBT Delay.

The UE 10 may measure a Buffer Status Report (BSR) LBT Delay, i.e., the time elapsed between triggering the BSR at MAC layer and transmitting the BSR in a BSR MAC CE over the air interface at the physical layer. In a variant of this embodiment, the BSR LBT Delay may be defined as the time from the start, or end, of the first LBT procedure to the start, or end, of the successful LBT procedure which precedes the, delayed, transmission. This time is thus zero if the LBT succeeds for the first transmission attempt. An example of how such a measurement is defined as follows.

Buffer Size Gap. The UE 10 may measure the “buffer size gap”, i.e., the difference, e.g., measured in bytes, between the buffer size included in a triggered BSR MAC CE and the buffer size, of the same buffer, of the UE, e.g., at RLC or MAC layer, at the time of the transmission over the air interface of the BSR MAC CE.

This embodiment is illustrated in the Fig. 7, where the buffer size content gap is computed as the buffer size difference between the buffer size measured at the moment in which the BSR is triggered, i.e. , the buffer size indicated in the BSR MAC CE, and the buffer size measured at the point in time in which the Physical Uplink Shared Channel (PUSCH) transmission including this BSR MAC CE is transmitted over the air interface:

Fig. 7 shows a buffer size gap in L2 measurement.

An example of how such a measurement is defined as follows, the size of the buffer referred below is the size of UL MAC buffer at the UE 10. Scheduling LBT Delay.

The radio network node 12 may measure a “Scheduling LBT Delay”, i.e., the gap between the scheduling of a MAC SDU and the transmission over the air-interface of the corresponding scheduling grant.

Logging and reporting of LBT delay in conjunction with other delay measurements.

Embodiments herein may be applied to, or combined with, any of the previously described embodiments involving delay measurements where delay caused by LBT failures may constitute a part of the total delay.

In one variant, for such measurements, the UE 10 or the radio network node 12 may log or store and/or report the LBT delay and the remainder of the total delay, i.e., the LBT independent part of the total delay, separately.

In another variant, for such measurements, UE 10 or the radio network node 12 may log or store and/or report the total delay as one item and the LBT delay, i.e., the part of the total delay that is caused by LBT procedures, as another item.

The radio network node 12 may configure the UE 10, e.g., through the system information or using dedicated signalling, e.g. radio resource control (RRC) signalling, how to log or store, and/or report delays where LBT procedures, in particular delay caused by LBT failures, may be part of the delay. To this end, as one option, the radio network node 12 may configure the UE 10 to log or store, and/or report such delays in accordance with any of the above described variants.

Reducing the impact of the buffer size gap.

Above describes a buffer size gap, which may result from a delay of the transmission of a BSR, e.g. caused by LBT failure(s) and/or delay. As previously described, this may have an adverse impact on the scheduling efficiency when the scheduling is based on outdated and incorrect information about the amount of data pending for transmission in the UE 10. In the embodiment described in this section, this negative impact may be mitigated by enabling more interaction between the MAC layer and the physical layer, i.e., the PHY layer. To this end, if the MAC layer, after providing a BSR to the physical layer for transmission, before receiving an indication from the physical layer that the requested transmission has been performed, determines that the size of the content of the buffer has changed, the MAC layer may instruct the physical layer to cancel the previously requested transmission and discard the concerned transport block(s), and instead provide a new updated BSR to the physical layer for transmission, wherein the updated BSR reflects the current content of the buffer.

As one option, this MAC layer behaviour may be subject to a condition on the size of the change of the buffer content size, e.g., the actions are triggered only if the buffer size has increased more than a, configured, specified or hardcoded by implementation, threshold. As another option, the condition that has to be fulfilled for the MAC layer to perform the above described actions is that the buffer size has increased more than a, configured, specified or hardcoded by implementation, first threshold-amount, e.g. measured in number of bytes, octets or bits, or has decreased more than a, configured, specified or hardcoded by implementation, second threshold-amount, e.g., measured in number of bytes, octets or bits, wherein the first and the second threshold-amounts may be different or equal to each other. Other condition variants are conceivable, e.g., including aspects such as the ratio between the size of the buffer size change and the buffer size before the change.

Additional impacts on L2 measurements.

Variants of the measurements described in the previous embodiments, e.g., LBT delay, cumulative LBT delay, SR LBT delay, BSR LBT Delay, can be defined by taking into account the impact of:

1) channel access procedure type. For example, for type 1 DL Channel Access procedure the time duration spanned by the sensing slots that are sensed to be idle before a downlink transmission(s) is random, while for Type 2 channel access procedure the time duration spanned by sensing slots that are sensed to be idle before a downlink transmission(s) is deterministic. In a possible implementation of cumulative LBT delay calculation, the deterministic time duration used for Type 2 channel access procedure can be made visible in the formula.

2) TDD pattern.

Impact of NR-U in L2 measurements collection period.

In another embodiment, the impact of NR-U can be considered by deducting the cumulative LBT delay, or another form of LBT delay, e.g., average, occurred during the Time Period during which a L2 measurement is performed and use the resulting “Time Period - Cumulative LBT delay” to calculate one of the existing Layer 2 measurements, where LBT delay is excluded.

For example, the table below from TS 38.314 v.16.0.0 may be modified as follows:

Table 4.2.1.2.2-2: Parameter description for Average over-the-air packet delay in the UL per DRB per UE excluding LBT delay

Embodiments herein disclose one or more methods listed as follows:

1. Method for a UE (or gNB) to measure the “LBT delay” experienced by the UE/gNB for transmitting a PDCP service data unit (SDU), wherein the “LBT delay” is measured at physical layer as the time elapsed between the reception of a transport block (TB) (including one or more parts of the PDCP SDU) from MAC layer and the transmission over the air interface of the TB or until the time the channel is declared busy (upon which the TB transmission does not occur). In an alternative, or variant embodiment, the LBT delay is regarded as zero if the LBT succeeds for the first transmission attempt, while if the LBT fails at the first transmission attempt, the LBT delay is measured as the time from the start (or end) of the first LBT procedure to the start (or end) of the successful LBT procedure which precedes the (delayed) transmission.

2. A method dependent on the previous method, where a UE (or gNB) measures the “cumulative LBT delay” experienced by the UE/gNB for transmitting a PDCP SDU. The “cumulative LBT delay” is the sum of all the “LBT delay” experienced by the UE for each of the TB including the parts of the PDCP SDU and measured over multiple scheduling occasions before the PDCP SDU is transmitted over the air interface.

3. A method dependent on method 1 and/or 2 above, wherein the LBT delay only considers the time associated to the slots in which the UE is scheduled for transmission, e.g. the LBT delay does not consider the time spent waiting for an UL transmission occasion in a TDD configuration.

4. A method in which the UE/gNB measures the “number of LBT failures” experienced by the UE for a PDCP SDU before transmitting it entirely (i.e. all the parts of the PDCP SDU) over the air interface. The number of LBT failures is measured as the number of TBs whose transmission was not performed due to LBT failure (i.e. channel sensed busy by the LBT procedure) and that included at least one part of the PDCP SDU

5. A method in which the UE measures the “SR LBT Delay” as the time elapsed between triggering the SR (as indicated by the MAC layer) and transmitting the SR over the air interface at the physical layer, where this time hence is a part of the total time between the triggering of the SR and the reception of an uplink grant (triggered by the SR). In a variant, the SR LBT delay is measured as the time from the trigger of the SR until the actual transmission of the SR, minus the delay from the SR trigger to the first PUCCH occasions for SR transmission (since this part of the delay is independent of LBT). In another variant, the SR LBT delay is measured in a similar way as described above for PDCP SDUs, i.e. the SR LBT delay is regarded as zero if the LBT succeeds for the first SR transmission attempt, while if the LBT fails at the first SR transmission attempt, the LBT delay is measured as the time from the start (or end) of the first LBT procedure to the start (or end) of the successful LBT procedure which precedes the (delayed) transmission.

6. A method in which the UE measures the “BSR LBT Delay”, i.e. the time elapsed between triggering the BSR at MAC layer and transmitting the BSR over the air interface at the physical layer. In a variant, the BSR LBT delay is measured as the time from the trigger of the BSR until the actual transmission of the BSR, minus the delay from the BSR trigger to the first PLICCH occasions for BSR transmission (since this part of the delay is independent of LBT). In another variant, the BSR LBT delay is measured in a similar way as described above for PDCP SDUs, i.e. the BSR LBT delay is regarded as zero if the LBT succeeds for the first BSR transmission attempt, while if the LBT fails at the first BSR transmission attempt, the LBT delay is measured as the time from the start (or end) of the first LBT procedure to the start (or end) of the successful LBT procedure which precedes the (delayed) transmission

7. A method in which the UE measures the “buffer size gap”, i.e. the difference (e.g. measured in bytes) between the buffer size included in a triggered BSR MAC CE and the buffer size of the UE (e.g. at RLC or MAC layer) at the time of the transmission over the air interface of the BSR MAC CE

8. A method in which the radio network node measures the “Scheduling LBT Delay”, i.e. the gap between the scheduling of a MAC SDU and the transmission over the air-interface of the corresponding scheduling grant.

9. A method in which the previous measurements or any other existing L2 measurements are measured separately per channel access priority class (CAPC), or separately for each CAPC in each DRB.

10. A method in which the previous measurements or any other existing L2 measurements are measured separately per shared spectrum channel bandwidth, or per shared spectrum operating band.

Fig. 8 is a block diagram depicting the UE 10 for handling communication or measurements in the wireless communications network 1 according to embodiments herein.

The UE 10 may comprise processing circuitry 701 , e.g., one or more processors, configured to perform the methods herein.

The UE 10 may comprise a receiving unit 702, e.g., a receiver or a transceiver. The UE 10, the processing circuitry 701 and/or the receiving unit 702 may be configured to obtain the configuration at the UE. The configuration or the policy comprises one or more rules that indicate to log a measurement such as an LBT delay measurement. The UE 10, the processing circuitry 701 and/or the receiving unit 702 may be configured to receive configuration data from the radio network node for configuring the UE 10 to perform the measurement. The UE 10 may comprise a performing unit 703, e.g., a measuring unit. The UE 10, the processing circuitry 701 and/or the performing unit 703 is configured to perform measurement of the parameter related to the LBT delay when accessing the channel. For example, the UE 10, the processing circuitry 701 and/or the performing unit 703 may be configured to measure a LBT delay, number of LBT failures or similar. The performed measurement may comprise measuring the LBT delay and/or counting a number of LBT failures. The measurement may be performed for each DRB; for each CAPC; or for each CAPC within each DRB; or separately per shared spectrum channel bandwidth, or per shared spectrum operating band. The performed measurement may comprise one or more of the following: a PDCP average delay in the UL per DRB; a point in time when a UL MAC PDU, including a first part of an UL PDCP SDU, is transmitted over an air interface; a time elapsed between triggering a SR and receiving a scheduling grant; a time elapsed between triggering a BSR at a MAC layer and transmitting the BSR in a BSR MAC CE, over an air interface at a physical layer; a difference between a buffer size included in a triggered BSR MAC CE and a buffer size of the UE at the time of the transmission over an air interface of the BSR MAC CE; deducting a cumulative LBT delay occurred during a time period during which a L2 measurement is performed and use the resulting time period minus the cumulative LBT delay to calculate the L2 measurement. The performed measurement may be affected by the LBT delay and/or consider an impact of the LBT delay in computation. The performed measurement may take into account an impact of channel access procedure type and/or TDD pattern.

The UE 10 may comprise a logging unit 704. The UE 10, the processing circuitry 701 and/or the logging unit 704 may be configured to log or store the measured parameter at the UE 10 and/or a measurement related to the measured parameter.

The UE 10 may comprise a transmitting unit 705, e.g. a transmitter or a transceiver. The UE 10, the processing circuitry 701 and/or the transmitting unit 705 may further be configured to transmit or report, to the radio network node 12, the indication, such as a value or an index, of the measured parameter and/or a measurement related to the LBT delay.

The UE 10 may comprise a memory 706. The memory 706 comprises one or more units to be used to store data on, such as data packets, one or more conditions, mobility events, measurements, events and applications to perform the methods disclosed herein when being executed, and similar. Furthermore, the UE 10 may comprise a communication interface 709 such as comprising a transmitter, a receiver, a transceiver and/or one or more antennas. The methods according to the embodiments described herein for the UE 10 are respectively implemented by means of, e.g., a computer program product 707 or a computer program, comprising instructions, i.e. , software code portions, which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the UE 10. The computer program product 707 may be stored on a computer-readable storage medium 708, e g., a disc, a universal serial bus (USB) stick or similar. The computer-readable storage medium 708, having stored thereon the computer program product, may comprise the instructions which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the UE 10. In some embodiments, the computer-readable storage medium may be a transitory or a non-transitory computer- readable storage medium. Thus, embodiments herein may disclose a UE 10 for handling measurements in a wireless communications network, wherein the UE 10 comprises processing circuitry and a memory, said memory comprising instructions executable by said processing circuitry whereby said UE 10 is operative to perform any of the methods herein.

Fig. 9 is a block diagram depicting the radio network node 12 for handling communication in the wireless communications network 1 according to embodiments herein.

The radio network node 12 may comprise processing circuitry 801 , e.g., one or more processors, configured to perform the methods herein.

The radio network node 12 may comprise a configuring unit 802, e.g., a transmitter or a transceiver. The radio network node 12, the processing circuitry 801 and/or the configuring unit 802 is configured to configure the UE 10 to log the measurement related to the LBT delay.

The radio network node 12 may comprise an obtaining unit 803, e.g., receiver or transceiver. The radio network node 12, the processing circuitry 801 and/or the receiving unit 803 may be configured to obtain the indication of the measurement of the parameter related to the LBT delay of the UE 10, when accessing the channel and/or a measurement related to the LBT delay. The indication may be a measured value or an index indicating the measured value. The indication and/or the measurement may be received from the UE 10 and/or measured at the radio network node 12. The indication and/or the measurement may comprise the measured LBT delay and/or the counted number of LBT failures. The indication and/or the measurement may be for each DRB; for each CAPC; for each CAPC within each DRB; separately per shared spectrum channel bandwidth, or per shared spectrum operating band. The indication and/or the measurement may comprise one or more of the following: a PDCP average delay in the UL per DRB; a point in time when a UL MAC PDU, including a first part of an UL PDCP SDU, is transmitted over an air interface; a time elapsed between triggering a SR, and receiving a scheduling grant; a time elapsed between triggering a BSR at a MAC layer and transmitting the BSR in a BSR MAC CE, over an air interface at a physical layer; a difference between a buffer size included in a triggered BSR MAC CE and a buffer size of the UE at the time of the transmission over an air interface of the BSR MAC CE; deducting a cumulative LBT delay occurred during a time period during which a L2 measurement is performed and use the resulting time period minus the cumulative LBT delay to calculate the L2 measurement. The indication and/or the measurement may be affected by the LBT delay and/or considers an impact of the LBT delay in computation.

The radio network node 12 may comprise a performing unit 808, e.g., receiver or transceiver. The radio network node 12, the processing circuitry 801 and/or the performing unit 808 may be configured to trigger an action based on the obtained indication and/or the measurement. The action may comprise reducing a load in a specific shared carrier and moving traffic to a less loaded shared carrier or to a licensed carrier. The action may comprise estimating performance taking the indication into account and/or measurement.

The radio network node 12 may comprise a memory 804. The memory 804 comprises one or more units to be used to store data on, such as data packets, mobility events, measurements, indications, logged measurements, configurations, events and applications to perform the methods disclosed herein when being executed, and similar. Furthermore, the radio network node 12 may comprise a communication interface 807 such as comprising a transmitter, a receiver, a transceiver and/or one or more antennas.

The methods according to the embodiments described herein for the radio network node 12 are respectively implemented by means of, e.g., a computer program product 805 or a computer program, comprising instructions, i.e. , software code portions, which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the radio network node 12. The computer program product 805 may be stored on a computer-readable storage medium 806, e.g. a disc, a universal serial bus (USB) stick or similar. The computer-readable storage medium 806, having stored thereon the computer program product, may comprise the instructions which, when executed on at least one processor, cause the at least one processor to carry out the actions described herein, as performed by the radio network node 12. In some embodiments, the computer-readable storage medium may be a transitory or a non-transitory computer-readable storage medium. Thus, embodiments herein may disclose a radio network node 12 for handling communication in a wireless communications network, wherein the radio network node 12 comprises processing circuitry and a memory, said memory comprising instructions executable by said processing circuitry whereby said radio network node 12 is operative to perform any of the methods herein.

In some embodiments a more general term “radio network node” is used and it can correspond to any type of radio-network node or any network node, which communicates with a wireless device and/or with another network node. Examples of network nodes are NodeB, MeNB, SeNB, a network node belonging to Master cell group (MCG) or Secondary cell group (SCG), base station (BS), multi-standard radio (MSR) radio node such as MSR BS, eNodeB, gNodeB, network controller, radio-network controller (RNC), base station controller (BSC), relay, donor node controlling relay, base transceiver station (BTS), access point (AP), transmission points, transmission nodes, Remote radio Unit (RRU), Remote Radio Head (RRH), nodes in distributed antenna system (DAS), etc.

In some embodiments the non-limiting term wireless device or user equipment (UE) is used and it refers to any type of wireless device communicating with a network node and/or with another wireless device in a cellular or mobile communication system. Examples of UE are target device, device to device (D2D) UE, proximity capable UE (aka ProSe UE), machine type UE or UE capable of machine to machine (M2M) communication, Tablet, mobile terminals, smart phone, laptop embedded equipped (LEE), laptop mounted equipment (LME), USB dongles etc.

Embodiments are applicable to any RAT or multi-RAT systems, where the wireless device receives and/or transmit signals (e.g. data) e.g. New Radio (NR), Wi-Fi, Long Term Evolution (LTE), LTE-Advanced, Wideband Code Division Multiple Access (WCDMA), Global System for Mobile communications/enhanced Data rate for GSM Evolution (GSM/EDGE), Worldwide Interoperability for Microwave Access (WiMax), or Ultra Mobile Broadband (UMB), just to mention a few possible implementations.

As will be readily understood by those familiar with communications design, that functions means or circuits may be implemented using digital logic and/or one or more microcontrollers, microprocessors, or other digital hardware. In some embodiments, several or all of the various functions may be implemented together, such as in a single application-specific integrated circuit (ASIC), or in two or more separate devices with appropriate hardware and/or software interfaces between them. Several of the functions may be implemented on a processor shared with other functional components of a wireless device or network node, for example.

Alternatively, several of the functional elements of the processing means discussed may be provided through the use of dedicated hardware, while others are provided with hardware for executing software, in association with the appropriate software or firmware. Thus, the term “processor” or “controller” as used herein does not exclusively refer to hardware capable of executing software and may implicitly include, without limitation, digital signal processor (DSP) hardware and/or program or application data. Other hardware, conventional and/or custom, may also be included. Designers of communications devices will appreciate the cost, performance, and maintenance trade-offs inherent in these design choices.

Any appropriate steps, methods, features, functions, or benefits disclosed herein may be performed through one or more functional units or modules of one or more virtual apparatuses. Each virtual apparatus may comprise a number of these functional units. These functional units may be implemented via processing circuitry, which may include one or more microprocessor or microcontrollers, as well as other digital hardware, which may include digital signal processors (DSPs), special-purpose digital logic, and the like. The processing circuitry may be configured to execute program code stored in memory, which may include one or several types of memory such as read-only memory (ROM), random-access memory (RAM), cache memory, flash memory devices, optical storage devices, etc. Program code stored in memory includes program instructions for executing one or more telecommunications and/or data communications protocols as well as instructions for carrying out one or more of the techniques described herein. In some implementations, the processing circuitry may be used to cause the respective functional unit to perform corresponding functions according one or more embodiments of the present disclosure.

With reference to Fig. 10, in accordance with an embodiment, a communication system includes a telecommunication network 3210, such as a 3GPP-type cellular network, which comprises an access network 3211 , such as a radio access network, and a core network 3214. The access network 3211 comprises a plurality of base stations 3212a, 3212b, 3212c, such as NBs, eNBs, gNBs or other types of wireless access points being examples of the radio network node 12 herein, each defining a corresponding coverage area 3213a, 3213b, 3213c. Each base station 3212a, 3212b, 3212c is connectable to the core network 3214 over a wired or wireless connection 3215. A first user equipment (UE) 3291, being an example of the UE 10, located in coverage area 3213c is configured to wirelessly connect to, or be paged by, the corresponding base station 3212c. A second UE 3292 in coverage area 3213a is wirelessly connectable to the corresponding base station 3212a. While a plurality of UEs 3291 , 3292 are illustrated in this example, the disclosed embodiments are equally applicable to a situation where a sole UE is in the coverage area or where a sole UE is connecting to the corresponding base station 3212.

The telecommunication network 3210 is itself connected to a host computer 3230, 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 3230 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 3221, 3222 between the telecommunication network 3210 and the host computer 3230 may extend directly from the core network 3214 to the host computer 3230 or may go via an optional intermediate network 3220. The intermediate network 3220 may be one of, or a combination of more than one of, a public, private or hosted network; the intermediate network 3220, if any, may be a backbone network or the Internet; in particular, the intermediate network 3220 may comprise two or more sub-networks (not shown).

The communication system of Figure 10 as a whole enables connectivity between one of the connected UEs 3291, 3292 and the host computer 3230. The connectivity may be described as an over-the-top (OTT) connection 3250. The host computer 3230 and the connected UEs 3291 , 3292 are configured to communicate data and/or signalling via the OTT connection 3250, using the access network 3211, the core network 3214, any intermediate network 3220 and possible further infrastructure (not shown) as intermediaries. The OTT connection 3250 may be transparent in the sense that the participating communication devices through which the OTT connection 3250 passes are unaware of routing of uplink and downlink communications. For example, a base station 3212 may not or need not be informed about the past routing of an incoming downlink communication with data originating from a host computer 3230 to be forwarded (e.g., handed over) to a connected UE 3291. Similarly, the base station 3212 need not be aware of the future routing of an outgoing uplink communication originating from the UE 3291 towards the host computer 3230.

Example implementations, in accordance with an embodiment, of the UE, base station and host computer discussed in the preceding paragraphs will now be described with reference to Fig. 11. In a communication system 3300, a host computer 3310 comprises hardware 3315 including a communication interface 3316 configured to set up and maintain a wired or wireless connection with an interface of a different communication device of the communication system 3300. The host computer 3310 further comprises processing circuitry 3318, which may have storage and/or processing capabilities. In particular, the processing circuitry 3318 may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The host computer 3310 further comprises software 3311, which is stored in or accessible by the host computer 3310 and executable by the processing circuitry 3318. The software 3311 includes a host application 3312. The host application 3312 may be operable to provide a service to a remote user, such as a UE 3330 connecting via an OTT connection 3350 terminating at the UE 3330 and the host computer 3310. In providing the service to the remote user, the host application 3312 may provide user data which is transmitted using the OTT connection 3350.

The communication system 3300 further includes a base station 3320 provided in a telecommunication system and comprising hardware 3325 enabling it to communicate with the host computer 3310 and with the UE 3330. The hardware 3325 may include a communication interface 3326 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of the communication system 3300, as well as a radio interface 3327 for setting up and maintaining at least a wireless connection 3370 with a UE 3330 located in a coverage area (not shown in Fig.11) served by the base station 3320. The communication interface 3326 may be configured to facilitate a connection 3360 to the host computer 3310. The connection 3360 may be direct or it may pass through a core network (not shown in Fig.11) of the telecommunication system and/or through one or more intermediate networks outside the telecommunication system. In the embodiment shown, the hardware 3325 of the base station 3320 further includes processing circuitry 3328, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The base station 3320 further has software 3321 stored internally or accessible via an external connection.

The communication system 3300 further includes the UE 3330 already referred to. Its hardware 3335 may include a radio interface 3337 configured to set up and maintain a wireless connection 3370 with a base station serving a coverage area in which the UE 3330 is currently located. The hardware 3335 of the UE 3330 further includes processing circuitry 3338, which may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions. The UE 3330 further comprises software 3331, which is stored in or accessible by the UE 3330 and executable by the processing circuitry 3338. The software 3331 includes a client application 3332. The client application 3332 may be operable to provide a service to a human or non-human user via the UE 3330, with the support of the host computer 3310. In the host computer 3310, an executing host application 3312 may communicate with the executing client application 3332 via the OTT connection 3350 terminating at the UE 3330 and the host computer 3310. In providing the service to the user, the client application 3332 may receive request data from the host application 3312 and provide user data in response to the request data. The OTT connection 3350 may transfer both the request data and the user data. The client application 3332 may interact with the user to generate the user data that it provides.

It is noted that the host computer 3310, base station 3320 and UE 3330 illustrated in Fig. 11 may be identical to the host computer 3230, one of the base stations 3212a, 3212b, 3212c and one of the UEs 3291 , 3292 of Fig. 10, respectively. This is to say, the inner workings of these entities may be as shown in Fig. 11 and independently, the surrounding network topology may be that of Fig. 10.

In Fig. 11 , the OTT connection 3350 has been drawn abstractly to illustrate the communication between the host computer 3310 and the user equipment 3330 via the base station 3320, 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 UE 3330 or from the service provider operating the host computer 3310, or both. While the OTT connection 3350 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 3370 between the UE 3330 and the base station 3320 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 UE 3330 using the OTT connection 3350, in which the wireless connection 3370 forms the last segment. More precisely, the teachings of these embodiments may improve the performance since mobility may be handled more efficiently taking into account LBT issues and thereby provide benefits such as reduced user waiting time, and better responsiveness.

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 3350 between the host computer 3310 and UE 3330, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection 3350 may be implemented in the software 3311 of the host computer 3310 or in the software 3331 of the UE 3330, or both. In embodiments, sensors (not shown) may be deployed in or in association with communication devices through which the OTT connection 3350 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 3311, 3331 may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 3350 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect the base station 3320, and it may be unknown or imperceptible to the base station 3320. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signalling facilitating the host computer’s 3310 measurements of throughput, propagation times, latency and the like. The measurements may be implemented in that the software 3311 , 3331 causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 3350 while it monitors propagation times, errors etc.

Fig. 12 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 10 and 11. For simplicity of the present disclosure, only drawing references to Figure 12 will be included in this section. In a first step 3410 of the method, the host computer provides user data. In an optional substep 3411 of the first step 3410, the host computer provides the user data by executing a host application. In a second step 3420, the host computer initiates a transmission carrying the user data to the UE. In an optional third step 3430, the base station transmits to the UE the user data which was carried in the transmission that the host computer initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional fourth step 3440, the UE executes a client application associated with the host application executed by the host computer.

Fig. 13 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 10 and 11. For simplicity of the present disclosure, only drawing references to Figure 13 will be included in this section. In a first step 3510 of the method, the host computer provides user data. In an optional substep (not shown) the host computer provides the user data by executing a host application. In a second step 3520, the host computer initiates a transmission carrying the user data to the UE. The transmission may pass via the base station, in accordance with the teachings of the embodiments described throughout this disclosure. In an optional third step 3530, the UE receives the user data carried in the transmission.

Fig. 14 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 10 and 11. For simplicity of the present disclosure, only drawing references to Figure 14 will be included in this section. In an optional first step 3610 of the method, the UE receives input data provided by the host computer. Additionally or alternatively, in an optional second step 3620, the UE provides user data. In an optional substep 3621 of the second step 3620, the UE provides the user data by executing a client application. In a further optional substep 3611 of the first step 3610, the UE executes a client application which provides the user data in reaction to the received input data provided by the host computer. In providing the user data, the executed client application may further consider user input received from the user. Regardless of the specific manner in which the user data was provided, the UE initiates, in an optional third substep 3630, transmission of the user data to the host computer. In a fourth step 3640 of the method, the host computer receives the user data transmitted from the UE, in accordance with the teachings of the embodiments described throughout this disclosure. Fig. 15 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment. The communication system includes a host computer, a base station and a UE which may be those described with reference to Figures 10 and 11. For simplicity of the present disclosure, only drawing references to Figure 15 will be included in this section. In an optional first step 3710 of the method, in accordance with the teachings of the embodiments described throughout this disclosure, the base station receives user data from the UE. In an optional second step 3720, the base station initiates transmission of the received user data to the host computer. In a third step 3730, the host computer receives the user data carried in the transmission initiated by the base station.

It will be appreciated that the foregoing description and the accompanying drawings represent non-limiting examples of the methods and apparatus taught herein. As such, the apparatus and techniques taught herein are not limited by the foregoing description and accompanying drawings. Instead, the embodiments herein are limited only by the following claims and their legal equivalents.

Abbreviation Explanation 5G 5th Generation 5GC 5G Core network Al Artificial Intelligence AR Augmented Reality BCH Broadcast Channel BCCH Broadcast Control Channel BSR Buffer Status Report BWP Bandwidth Part CA Carrier Aggregation CAPC Channel Access Priority Class CC Carrier Component CCA Clear Channel Assessment CCCH Common Control Channel CCE Control Channel Element CE Control Element COT Channel Occupancy Time CP Control Plane CU Centralized Unit CU-CPCentralized Unit - Control Plane

CU-UPCentralized Unit - User Plane

CW Contention Window

CWp Contention window for a given priority class.

CWS Contention Window Size

D2D Device to Device

DC Dual Connectivity

DCCH Dedicated Control Channel

DL Downlink

DL-SCH Downlink Shared Channel

DTCH Dedicated Traffic Channel

DU Distributed unit

E1 The interface between a gNB-CU-CP and a gNB-CU-UP in the split RAN architecture in NR.

ED Energy Detection eNB Evolved NodeB

EPC Evolved Packet Core

ETSI European Telecommunications Standards Institute

F1 The interface between a gNB-Cll and a gNB-Dll in the split RAN architecture in NR.

F1-LI The user plane part of the F1 interface, e.g. the interface between a gNB-Dll and a gNB-CU-UP.

FBE Frame Based Equipment

FDD Frequency Division Duplex

FPP Fixed Frame Period

GBR Guaranteed Bit Rate gNB A radio base station in NR gNB-CU gNB Centralized Unit gNB-CU-CP gNB Centralized Unit Control Plane gNB-CU-UP gNB Centralized Unit User Plane gNB-DU gNB Distributed Unit

HO Handover

IE Information Element

IMS IP Multimedia Subsystem

IP Internet Protocol LBE Load Based Equipment

LBT Listen-Before-Talk

LTE Long Term Evolution

MAC Medium Access Control

MCOT Maximum Channel Occupancy Time

ML Machine Learning

MLB Mobility Load Balancing

MTC Machine Type Communication

MTSI Multimedia Telephony Service for IMS

NG The interface between the RAN and the core network in 5G.

NG-RAN 5G RAN

NR New radio

NR-U NR Unlicensed (l.e. NR operated in shared (unlicensed) spectrum.)

OFDM Orthogonal Frequency Division Multiplexing

PBCH Physical Broadcast Channel

PCH Paging Channel

PCCH Paging Control Channel

PDCCH Physical Downlink Control Channel

PDCP Packet Data Convergence Protocol

PDSCH Physical Downlink Shared Channel

PDU Protocol Data Unit

PHY Physical layer

PRB Physical Resource Block

PUCCH Physical Uplink Control Channel

PUSCH Physical Uplink Shared Channel

QoS Quality of Service

RAN Radio Access Network

RAT Radio Access Technology

RLC Radio Link Control

RNL Radio Network Layer

RRC Radio Resource Control

RSRP Reference Signal Received Power

RSRQ Reference Signal Received Quality

SCS Subcarrier Spacing

SDU Service Data Unit SI NR Signal to Interference and Noise Ratio

SON Self-Organizing Network / Self-Optimizing Network

SR Scheduling Request

SSB Synchronization Signal Block

TDD Time Division Duplex

TNL Transport Network Layer

TS Technical Specification

UE User Equipment

UL Uplink

UP User Plane

URLLC Ultra-Reliable Low-Latency Communication

V2X Vehicle-to-everything (Or “Vehicle to X”, where X e.g. may be another vehicle or a network server.)

VR Virtual Reality

X2 The interface between two eNBs in LTE.

X2AP X2 Application Protocol

Xn The interface between two gNBs in NR.

XnAP Xn Application Protocol