Enhanced buffer status report

Abstract

A method performed in a user equipment, UE (1), for controlling uplink transmission of data to a base station (110) of a wireless network (100), the method comprising: sending (806) a buffer status report, BSR (85), indicative of a buffer data level value to the base station; sending (806) information (86) indicative of a packet arrival rate of data into a transmission buffer to the base station; receiving (811) uplink resource information (87) from the base station in response to the BSR and the information; and transmitting (812) data (88) from the buffer using the received resource information.

Description

TECHNICAL FIELD

[0001] The present disclosure relates generally to communication systems. More specifically, the present disclosure relates to systems and methods associated with an enhanced buffer status reporting (BSR) procedure by transmitting information indicating the packet arrival rate of data entering a transmission buffer. BACKGROUND

[0002] Electronic devices typically include wireless communication circuitry, and such electronic devices can be referred to as wireless terminals. For example, cellular telephones, computers, and other devices often contain antennas and wireless transceivers for supporting wireless communication. In 3GPP (Third Generation Partnership Project) documentation, wireless terminals or wireless communication devices are often referred to as user equipment (UE). The term will be used herein, but should not be interpreted as limited to operation under 3GPP specifications. A base station defines a cell, and provides radio access services for an area around by providing radio access to UEs within the cell. A base station can also be referred to as an access node, and various terms are used in 3GPP for different types of systems or specifications. An access network or radio access network (RAN) typically includes multiple access nodes, and is connected to a core network (CN) that among other things provides access to other communication networks. In the so-called 3G specifications, the term NodeB is used to denote an access node, while in the so-called 4G specifications, also known as Long Term Evolution (LTE), the term eNodeB (eNB) is used. A further development of specifications for radio communication is referred to as 5G-type radio communication system (5GS), including New Radio (NR) technology, where the term gNB is used to denote an access node. In NR, communication can be suitably configured in frequency bands into the millimeter wave spectrum, such as around 28 GHz and above. In this spectrum, wireless terminals and base stations can be configured for beamforming, whereby transmission and reception can be spatially focused into beams covering a specific direction and width or cone angle.

[0003] Many types of wireless terminals are most frequently used for receiving data from a wireless network, e.g. for streaming or downloading of data. However, for certain applications, uplink (UL) transmission of data is a main feature. This can for example involve real-time upload of streaming video data, as captured by a video camera device. Furthermore, it can also be required to transmit high quality (e.g. high definition, ultra-high definition, 4K) video transmissions, and resulting in continuous, large packet sizes and time-sensitive uplink transmissions.

[0004] In conventional UL transmissions, the UE is configured to first transmit buffer status report (BSR) information so that the network can allocate physical resources for UL transmissions from the UE in a time / frequency resource grid. Typically, the UE can be configured to periodically report BSR. Once the network receives the BSR, the network will allocate UL resources for the UE so that the UE can clear its buffer. Any subsequent data for UL transmission provided in the UE after the BSR transmission will be input into the UE buffer and transmitted later once the UE reports a subsequent BSR.

[0005] Recent developments in wireless communications that provide substantial UL transmissions present challenges to resource allocation. In particular, improvements are needed to minimize the risk of delay associated with UL transmissions of latency-sensitive data. SUMMARY

[0006] In view of these challenges, the present disclosure is directed to providing a solution for controlling uplink transmission of data from a UE to a base station of a wireless network.

[0007] According to one aspect, there is provided a method of controlling uplink transmission of data to a base station of a wireless network performed in a user equipment, UE, the method comprising:

[0008] transmitting, to the base station, a buffer status report, BSR, indicative of a buffer data level value;

[0009] transmitting, to the base station, information indicative of a packet arrival rate of data entering the transmission buffer;

[0010] receiving, from the base station, uplink resource information in response to the BSR and the information; and

[0011] transmitting data from the buffer using the received resource information.

[0012] Accordingly, the base station will be able to allocate UL resources to the UE based on the received BSR and information until the next BSR report. In addition to allocating resources based on the buffer data level value of the BSR, the base station can also allocate additional UL resources based on the received information. Thus, once the UE receives a new packet entering the buffer, e.g., from an application, the packet can be transmitted without having to buffer the data for transmission based on a subsequent BSR. In this way, packet delay is minimized. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 Wireless networks and communications between UEs and various base stations according to various embodiments are schematically illustrated.

[0014] Figure 2 A UE configured to operate according to various embodiments is schematically illustrated.

[0015] Figure 3 A base station configured to operate according to various embodiments is schematically illustrated.

[0016] Figure 4 General communications related to buffer status reporting between a UE and a base station are schematically illustrated.

[0017] Figure 5 Emptying of a transmission buffer based on a BSR is illustrated.

[0018] Figure 6 A flowchart of a method performed in a UE according to various embodiments is schematically illustrated.

[0019] Figure 7 A flowchart of a method performed in a base station according to various embodiments is schematically illustrated.

[0020] Figure 8 A signaling diagram between a base station and a UE of a wireless network for enhanced buffer status reporting according to various embodiments is schematically illustrated.

[0021] Figure 9A And Figure 9B Measurements related to BSR using prior art methods are illustrated.

[0022] Figure 10A And Figure 10B Measurements related to BSR using embodiments outlined herein are illustrated.

[0023] Figure 11A And Figure 11B Measurements related to BSR using embodiments outlined herein are illustrated.

[0024] Figure 12A And Figure 12B Measurements related to BSR using embodiments outlined herein are illustrated. DETAILED DESCRIPTION

[0025] In the following description, for purposes of explanation and not limitation, specific details are set forth relating to the various embodiments. However, it will be apparent to those skilled in the art that the present application can be practiced in other embodiments that depart from these specific details. In some instances, detailed descriptions of well-known devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail. The functions of the various elements including functional blocks can be provided through the use of hardware such as circuitry and / or hardware and / or software (including firmware, resident software, micro-code, etc.) able to be executed by a processor, which can include, by way of example, general purpose processors or application-specific processors. Hence, functions of the various elements including functional blocks can be either hardware or software (including firmware, resident software, micro-code, etc.), which can be embodied in hardware and / or software (including firmware, resident software, micro-code, etc.) that can be executed by a processor, which can include, by way of example, general purpose processors or application-specific processors. The software program can be stored in a storage device, such as a computer readable medium, including a floppy disk device, a hard disk device, or a removable memory, programmable logic devices, and / or optical storage devices, such as compact disk read-only memory (CD-ROM), digital video disk read-only memory (DVD-ROM) and / or a global positioning system (GPS) device. While the application has been described in terms of various specific embodiments, it will be apparent to those with ordinary skill in the art that modifications and / or alterations can be suggested without departing from the scope of the application. Moreover, it is to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting. It is also to be understood that the terminology could be interchangeable under the appropriate circumstances such that the description of the present application is intended to be generic. Accordingly, the present application is not limited to that precisely as shown and described.

[0026] The drawings are to be considered in all respects illustrative and the elements illustrated in the drawings are not necessarily to scale. Rather, various elements are represented so as to facilitate understanding of the present application. Any connection or coupling between functional blocks, devices, components, or other physical or functional units shown in the drawings or described herein can also be implemented by an indirect connection or coupling, as well as direct connections or couplings. Coupling between components can also be established over a wireless connection. Functional blocks can be implemented in hardware, firmware, software, or a combination thereof.

[0027] Figure 1A wireless communication system is schematically illustrated, providing an example of a scenario in which the solutions provided herein can be incorporated. The wireless communication system comprises a wireless network 100 and a UE (or terminal) 1 configured to wirelessly communicate with the wireless network 100. The wireless network can be a radio communication network operating under general and specific specifications and limitations published by 3GPP, such as a New Radio (NR) network. The wireless network 100 can comprise a core network 101 connected to other networks 120, e.g. the Internet. The wireless network 100 further comprises an access network 102 comprising a plurality of base stations or access nodes 110, 111. A base station is an entity performing wireless connectivity with UEs. As such, each base station 110, 111 comprises or is connected to an antenna arrangement 10, 11 for transmission and reception of radio signals. The actual transmission and reception point of a base station can be referred to as a transmission and reception point (TRP). The TRP can be seen as comprising or being co-located with the antenna system 10, 11 of the base station 110, 111. The base stations 110, 111 can be gNBs and be configured for beamforming introduced for 5G. The figure further shows a network node 103 which can incorporate functionality for managing communication and cooperation with the base stations 110, 111, e.g. user plane functionality. In various implementations, a logical communication interface can be provided between the base stations 110, 111.

[0028] The UE 1 can be any device operable to wirelessly communicate with the network 100 through the base stations 110, 111, such as a mobile phone, a computer, a tablet, a M2M device or other device. The UE 1 can be configured to communicate in more than one beam, preferably orthogonal in code and / or frequency and / or time division. The beam configuration in the UE 1 can be achieved by using an antenna array configured to provide an anisotropic sensitivity distribution to transmit radio signals in a specific transmission direction.

[0029] Figure 2 Embodiments for a UE 1 in a wireless network 100 as presented herein are schematically illustrated, and for performing the outlined method steps.

[0030] The UE 1 can comprise a radio transceiver 213 for communicating with other entities of the radio communication network 100, e.g. the base stations 110, 111, in different frequency bands. The transceiver 213 can thus comprise a radio receiver and transmitter for communicating over at least one air interface.

[0031] The UE 1 further comprises a logic unit 210 configured to transmit data to the wireless communication network 100 via the radio transceiver over the radio channel, and possibly directly with another terminal by device-to-device (D2D) communication.

[0032] The logic unit 210 can comprise a processing device 211 comprising one or more processors, microprocessors, data processors, co-processors, and / or some other type of component that interprets and / or executes instructions and / or data. The processing device 211 can be implemented as hardware (e.g., a microprocessor, etc.) or a combination of hardware and software (e.g., a system-on-chip (SoC), an application-specific integrated circuit (ASIC), etc.). The processing device 211 can be configured to perform one or more operations based on an operating system and / or various applications or programs.

[0033] The logic unit 210 can further comprise a storage 212, which can comprise one or more memories and / or one or more other types of storage media. For example, the storage 212 can comprise random access memory (RAM), dynamic random access memory (DRAM), cache, read only memory (ROM), programmable read only memory (PROM), flash memory, and / or some other type of memory. The storage 212 can comprise a hard disk (e.g., a magnetic disk, an optical disk, a magneto-optic disk, a solid-state disk, etc.).

[0034] The storage 212 is configured to hold computer program code that can be executed by the processing device 211, wherein the logic unit 210 is configured to control the UE 1 to perform any of the method steps provided herein. The software defined by the computer program code can comprise applications or programs that provide functionality and / or processes. The software can comprise device firmware, an operating system (OS), or various applications that can be executed in the logic unit 210.

[0035] The UE 1 can further comprise an antenna 214, which can comprise an antenna array. The logic unit 210 can further be configured to control the radio transceiver to employ an anisotropic sensitivity profile of the antenna array for transmitting radio signals in a certain transmission direction. In various embodiments, this can involve applying a transmission spatial filter 215A to adjust the spatial sensitivity of the antenna 214, especially in UL transmissions, and applying a reception spatial filter 215B to adjust the spatial sensitivity of the antenna 214, especially in DL receptions. Depending on the implementation, the spatial filters 215A, 215B can comprise groups of phase shifters, which can be independent.

[0036] The UE 1 also implements a buffer 216, which can receive data from units or applications operating in the UE 1, for UL transmission using the transceiver 213. The logic unit 210 is configured to transmit a BSR to the wireless network 100, which reflects the status of the buffer 216, which is at least related to the data level present in the buffer 216.

[0037] It is clear that the terminal can comprise other features and elements than the ones shown in the figures or described herein, such as a power supply, a housing, a user interface, one or more sensors, and units configured to provide data to the buffer, such as a video camera or the like. Furthermore, additional levels of buffers can be implemented in the terminal. When referring to the buffer 216 herein, this can be a buffer for data available in the communication modem of the terminal, while additional buffers and memory can reside in other functions of the terminal. For example, in addition to the buffer 216 available for lower layer modem signaling for resource allocation for wireless transmission, a video or image capturing device within the terminal or coupled to an application residing in the terminal can store data in one or more buffers.

[0038] Figure 3 A base station 110 for use in the wireless telecommunication network 100 presented herein and for performing the method steps outlined here is schematically illustrated. It should be noted that Figure 3 Embodiments of the base station 110 can likewise be used in the second base station 111.

[0039] The base station 110 comprises a base station of the wireless telecommunication network 100, e.g. a gNB, or works as a base station of the wireless telecommunication network 100, e.g. a gNB. The base station 110 can comprise a radio transceiver 313 for wireless communication with other entities of the wireless telecommunication network 100, e.g. the UE 1. The transceiver 313 can thus comprise a radio receiver and a transmitter for communication over at least one air interface.

[0040] The base station 110 further comprises a logic unit 310 configured to communicate data with the UE 1 via the radio transceiver over a radio channel. The logic unit 310 can comprise a processing device 311 comprising one or more processors, microprocessors, data processors, co-processors, and / or some other type of component that interprets and / or executes instructions and / or data. The processing device 311 can be implemented as hardware (e.g., a microprocessor, etc.) or a combination of hardware and software (e.g., a system-on-chip (SoC), an application-specific integrated circuit (ASIC), etc.). The processing device 311 can be configured to perform one or more operations based on an operating system and / or various applications or programs.

[0041] The logic unit 310 can further comprise a storage 312, which can comprise one or more memories and / or one or more other types of storage media. For example, the storage 312 can comprise random access memory (RAM), dynamic random access memory (DRAM), cache memory, read only memory (ROM), programmable read only memory (PROM), flash memory, and / or some other type of memory. The storage 312 can comprise a hard disk (e.g., a magnetic disk, an optical disk, a magneto-optic disk, a solid-state disk, etc.).

[0042] The memory 312 is configured to hold computer program code that can be executed by the processing device 311, wherein the logic unit 310 is configured to control the base station 110 to perform any of the method steps provided herein. The software defined by the computer program code can comprise applications or programs providing functions and / or processes. The software can comprise device firmware, operating systems (OS), or various applications that can be executed by the logic unit 310.

[0043] The base station 110 can further comprise or be connected to an antenna 314, which can comprise an antenna array, connected to the radio transceiver 313. The logic unit 310 can further be configured to control the radio transceiver to transmit and / or receive radio signals in specific transmission directions employing the anisotropic sensitivity profile of the antenna array. In various embodiments, this can comprise applying a transmit spatial filter 315A to adjust the spatial sensitivity of the antenna 314, in particular in DL transmissions, and applying a receive spatial filter 315B to adjust the spatial sensitivity of the antenna 314, in particular in UL reception. The base station 110, or alternatively only the antenna 314, can form a transmission point, TRP, of the base station 110.

[0044] The base station 110 can further comprise a communication interface 316, which can be operable to cause the base station 110 to communicate with other nodes of the wireless network 100, such as the higher network node 103, or with another base station 111.

[0045] The logic unit 310 is configured to determine resource allocations to UEs operating within the cell of the base station 110, in particular based on BSRs received from the UEs, and to transmit resource allocation information to the UEs.

[0046] In various embodiments, the base station 110 is configured to perform the method steps outlined herein that are performed in a base station.

[0047] Various embodiments will now be described, with reference to the drawings.

[0048] Figure 4The BSR and UL transmission is schematically illustrated on a general level. The UE 1 preferably transmits BSR information to the connected base station 110 periodically at regular intervals. In conventional systems, the BSR period is within 10 ms to 1 sec. Once the network receives the BSR, the base station 110 will allocate UL resources for the UE 1 so that the UE 1 can clean up its buffer 216.

[0049] The BSR in NR is currently described in the 3GPP document TS 38.321. The procedure is almost similar to LTE (in LTE, the UE only reports buffer size status). The specification defines Table 1 as shown below, where it is defined what index is reported for a certain level of data buffer size (BS value) present in the buffer 216:

[0050] Table 6.1.3.1-1: Buffer Size Levels for 5-bit Buffer (in bytes)

[0051] Index BS value Index BS value Index BS value Index BS value 0 0 8 ≤102 16 ≤1446 24 ≤20516 1 ≤10 9 ≤142 17 ≤2014 25 ≤28581 2 ≤14 10 ≤198 18 ≤2806 26 ≤39818 3 ≤20 11 ≤276 19 ≤3909 27 ≤55474 4 ≤28 12 ≤384 20 ≤5446 28 ≤77284 5 ≤38 13 ≤535 21 ≤7587 29 ≤107669 6 ≤53 14 ≤745 22 ≤10570 30 ≤150000 7 ≤74 15 ≤1038 23 ≤14726 31 >150000

[0052] Table 1

[0053] Placing UL payload in the buffer 216 can increase packet delay, and the applicant has found that this can cause problems. Tests run by the applicant have shown that the delay can be problematic for at least certain applications where latency is critical, such as UL transmission of video data for instant or live reproduction and presentation. The following is an example obtained from the applicant’s measurements:

[0054] The scenario is 40 Mbps uplink streaming, packet size = 1 KB, traffic rate = 5 packets / ms.

[0055] The gNB is configured with bandwidth (BW) = 100 MHz, band = n78 (with 30khz subcarrier spacing (SCS)), with TDD with 4DL:1UL, periodic BSR = 10 ms, maximum cell rate ~ 86 Mbps.

[0056] This configuration results in: 40 Mbit / s = 5 MByte / s = 50 KB / 10 ms (50 KB / BSR period). This means that the UE 1 receives ~ 50 KB of data into its buffer 216 during each BSR period. The data can be received, for example, from an application or unit for providing video data.

[0057] Since the data traffic arriving at the buffer 216 between the BSRs is not scheduled by the base station 110, the buffer 216 will remain at ~ 50 KB. Subsequently, the UE will report BSR index 27, sometimes index 26 mentioned in Table 1.

[0058] Figure 5The resulting resource configuration (i.e. transport block size (TBS) for uplink transmission) of the UE is shown in the upper part of the figure, wherein the BSR instances are shown in the lower part. One BSR 501 is provided by the UE 1 and transmitted as BSR information to the base station 110. In this example, the UE 1 sends BSR = 27 (< 55474 bytes). In return, the UE 1 will receive control data including a corresponding UL grant from the base station 110, wherein the scheduled resource allocation takes place in a subsequent window 510 representing an allocation period. It can be observed that the gNB base station 110 tries to clean the buffer 216 by allocating 55441 bytes by choosing a higher modulation and coding scheme (MCS) / transport block size (TBS) for the first few transmissions 511 after the BSR. In this case, there are two cases where the allocated TBS is relatively large, larger than 25000 bits. Then, when the UE buffer 216 is empty, the MCS / TBS will be dropped, as indicated by 512. No additional incoming traffic is allocated after the BSR 501, and any new arriving packets will be buffered and wait for the next BSR report. (It can be seen that in the next BSR cycle, a BSR = 26 (< 39818 bytes) is transmitted, thus only one UL transmission occasion is needed).

[0059] In this case, the statistics on the uplink delay show an average of 14.9 ms and a maximum delay of 20 ms. The Applicant notes that, although NR supports Ultra-Reliable Low-Latency Communication (URLLC) services with very strict latency requirements, this delay can lead to unacceptable results for certain applications.

[0060] A solution is provided herein for minimizing the possible long packet delay by the function of allocating UL resources to the UE, even in the case where the UE buffer 216 reported in the BSR has been emptied. This is achieved by introducing some new UE assistance parameters and signaling between the UE 1 and the wireless network 100, e.g. in particular the serving base station 110. In various embodiments, this is obtained by providing the base station 110 with packet arrival rate information, reflecting the input arrival / traffic rate of packets entering the UE transmission buffer 216. The packet arrival rate can be given, for example, by a value of amount of data per time unit, such as Mb / s or other suitable unit, or by a number of packets per time unit, wherein a packet can correspond to a certain amount of data or a certain maximum amount of data.

[0061] Figure 6 A flowchart of the solution is schematically shown, which provides a method performed in the UE 1 for controlling the UL transmission of data to the base station 110 of the wireless network 100. The method comprises:

[0062] transmit 614 a BSR indicating the buffer data level value to the base station 110;

[0063] transmit 616 information indicating the packet arrival rate of data into the transmission buffer 216 to the base station 110;

[0064] in response to the BSR and the information, receive 618 UL resource information from the base station 110; and

[0065] transmit 620 data from the buffer 216 using the received resource information.

[0066] Figure 7 A flow chart illustrating the proposed solution from the network's perspective is shown. Here, a method performed in a base station 110 of a wireless network 100 for controlling UL transmission of data from a UE is provided.

[0067] The method comprises:

[0068] receive 710 a BSR from the UE 1 indicating a data level value of the transmission buffer 216 of the UE 1 ;

[0069] receive 712 information from the UE 1 indicating a packet arrival rate of data into the transmission buffer 216;

[0070] transmit 714 UL resource information allocated in response to the BSR and the information to the UE 1 ; and

[0071] receive 716 data transmitted in the UL from the UE using the resource information.

[0072] As provided in both aspects of the proposed general solution, the base station 110 allocates UL resources to the UE 1 based on the received BSR and information until the next BSR report. In addition to allocating resources based on the buffer data level value of the BSR, the base station can allocate additional UL resources based on the expected data into the buffer based on the information indicating the packet arrival rate. Thus, as soon as the UE 1 receives a new packet, e.g. from an application, into the buffer 216, the allocated resources can be used to transmit the packet without having to buffer data for transmission based on a subsequent BSR. In this way, packet delay is minimized.

[0073] Figure 8 A signaling diagram illustrating embodiments falling within the scope of the above provided general solution is shown. Various embodiments and alternative detailed solutions associated with the general solution will now be discussed, while also referring to Figure 8 and measurement results provided in Figures 9A to 12B

[0074] ​Before discussing further details, and for the sake of comparison, Figure 9A and Figure 9B This illustrates the data buffering and transmission of a UE operating under a traditional solution, and the resulting packet latency. From Figure 9A In the top graph, the buffer occupancy level is represented by a solid line. Packets arrive at the UE at a constant rate, thus increasing the allocated buffer size. In BSR 901, the buffer occupancy level is reported. In response to this, and for the next UL allocation cycle (corresponding to 510), the base station allocates UL resources and notifies the UE. Specifically, the base station seeks to clear the buffer, and the UE subsequently utilizes the allocated resources in UL timing 902. This is also reflected in the decrease in the buffer occupancy level in the top graph. Each UL allocation is large enough to carry a large number of packets, as shown in 905. Each of these packets will have a corresponding delay corresponding to its buffering time, as shown in 904. To fully utilize the UL allocation size, it may be necessary to segment the buffered packets. If segmented, the packet delay is measured only when the last segment is received. Segments are represented by a star, while complete packets and the last segment are represented by a full circle. During this BSR cycle, no resource allocation is provided for another UL timing. However, as can be seen from the top graph, the buffer continues to fill during this cycle until the subsequent BSR timing 903. Figure 9B The resulting packet delay is shown.

[0075] Back Figure 8 The proposed solution for minimizing packet delay involves providing an indication of the packet arrival rate in the UE buffer 216 to the base station 110.

[0076] In some implementations, information 86 indicating the packet arrival rate 84 is transmitted 616, 806 within or together with the transmission of BSR 85. In various implementations, this requires the transmission of BSR 85 and information 86 indicating the packet arrival rate within the same Medium Access Control-Control Element (MACCE). In one implementation, the packet arrival rate information 86 can therefore be embedded along with BSR 85. This may require including the packet arrival rate information 86 as extended information in a message including BSR 85, or as a message transmitted sequentially with the BSR. Thus, there can be two types of BSRs: BSR_type1 (legacy) and BSR_type2 (new, with packet arrival rate indication). In another implementation, information 86 indicating the packet arrival rate is transmitted 616, 806 as a separate message before or after the transmission of BSR 85.

[0077] The data level value 83 of the transmission buffer 216 can be obtained 610, 804 from a function controlling the buffer 216 in the UE 1, and the obtaining can be performed e.g. according to any prior art method used in connection with the transmission buffer 216.

[0078] In some embodiments, the packet arrival rate 84 is determined at a point in time between the transmission 616 of the BSR 85 and the previous BSR. Alternatively, the packet arrival rate 84 is determined at the same time as the data level value 83 is obtained 804, e.g. by obtaining 804, 805 both the data level value 83 and the packet arrival rate 84 from a UE function (not shown) controlling the transmission buffer 216.

[0079] In some embodiments, the packet arrival rate 84 is determined once within a BSR period and considered valid for use until the occasion of determining a packet arrival rate 84 for a subsequent BSR period. Alternatively, the determined packet arrival rate 84 is considered valid for use for a plurality of subsequent BSR periods. In such embodiments, new information 86 indicating the packet arrival rate 84 is transmitted 616, 806 only when a new packet arrival rate 84 has been obtained 612, 805, or e.g. a flag or code can be transmitted 616, 806 to indicate an unchanged packet arrival rate until a new value is obtained 612, 805. The packet arrival rate 84 can be determined by estimation or calculation, e.g. based on the number of packets received in the buffer 216 within a certain window, such as the preceding BSR period or a shorter or longer time frame. In other embodiments, the packet arrival rate can be determined at least partly based on the type of data or the type of application or function providing data to the buffer, e.g. video data provided by an application for video recording. Thus, the determination of the packet arrival rate can be performed by a calculation in an upper layer, e.g. an application layer, from which the logical unit 210 can obtain 805 the packet arrival rate in the MAC layer, e.g. performing the BSR.

[0080] In some embodiments, the information 86 indicating the packet arrival rate is selectively transmitted 616, 806 based on the BSR control data 81, 82. As mentioned above, the BSR control data 81, 82 can depend on the application providing data to the buffer 216. In some embodiments, the BSR control data 81, 82 can depend on quality of service, QoS, requirements or QoS flow IDs, QFIs.

[0081] In some embodiments, the BSR control data 82 can be determined 803 by the UE 1, e.g. depending on the type of application providing data to the buffer 216, or determined QoS requirements or QFI. In alternative embodiments, the BSR control data 81 is transmitted 705, 801 from the base station 110 to be received 605, 802 in the UE 1. In this way, the UE 1 is configured to provide information 86 indicative of the packet arrival rate based on an obtained base station request forming said control data 81. Such BSR control data 81 can be transmitted 705, 801 based on the application providing data to the buffer or QoS requirements, for example. Alternatively, a control function (not shown) presenting data of a quality, such as a video data presentation, can provide control data based on a determined quality or delay associated with the presentation, whereby the control data 81 is obtained in the base station 110, e.g. from a data presentation device (e.g. a display function, not shown), to be transmitted 705 to the UE 1.

[0082] In some embodiments, the information 86 indicative of the packet arrival rate comprises a measured packet arrival rate by the UE, e.g. a data value.

[0083] Figure 10A and Figure 10B A diagram is shown corresponding to the conventional solution of Figure 9A and Figure 9B but where the base station is provided with a measured value of the packet arrival rate 84. From the top diagram of Figure 10A the buffer occupancy level is indicated by the solid line. At the BSR occasion 1001, the UE 1 reports the buffer occupancy level. In addition, information 86 indicative of the packet arrival rate is provided by the UE 1, in this example by a measured or estimated value, e.g. an exact value. In response to this, the base station 110 allocates UL resources and informs the UE 1. The base station 110 is configured to seek to empty the buffer at the earliest possible occasion, and allocates resources for this purpose to be used at the UL occasion 1002. In addition, based on the information 86, additional resources are allocated and scheduled for subsequent UL occasions 1003 within the same BSR period, before the next BSR 1004. In this example, the base station is configured to allocate a uniform amount of resources for each occasion 1003 for data estimated to enter the buffer, based on the information 86, after the first occasion 1002 for emptying the buffer based on the BSR 85. In alternative embodiments, a decreasing amount of resources can be scheduled for each UL occasion in the period of 1003.

[0084] Figure 10B A resulting packet count versus packet delay is shown, which can be seen to have a significant improvement in both maximum delay and average delay. It can be noted that Figure 10BThe tail in the graph is the result of packets entering the buffer after the first BSR without prior information 86 indicating the packet arrival rate.

[0085] In other embodiments, the information 86 indicating the packet arrival rate is pre-defined, e.g. in the form of a look-up table, in order to minimize the size of the information to be transmitted. Thus, the information 86 indicating the packet arrival rate can comprise a data value representing the quantized arrival rate level 84. This is in order to save the amount of data 86 to be reported, e.g. limit the number of bits needed to indicate the level of the packet arrival rate 84, e.g. packets / time unit or packets*packet size / time.

[0086] In one embodiment, the packet arrival rate 84 is quantized with actual numbers, e.g. as shown in the example of table 2 below. The unit used for quantizing the information 86 can be e.g. KB / msec, as shown in table 2, or KB / BSR-rep-interval.

[0087] Packet arrival rate report Size 000 0 (no report) 001 ≤ 10 KB / msec 010 ≤ 30 KB / msec 011 ≤ 50 KB / msec 100 ≤ 100 KB / msec 101 ≤ 300 KB / msec 110 ≤ 500 KB / msec 111 > 500 KB / msec

[0088] Table 2

[0089] Figure 11A and Figure 11B shows a graph corresponding to the embodiment of Figure 10A and Figure 10B but where the base station is provided with quantized values of the packet arrival rate 84. According to the top graph of Figure 10A the buffer occupancy level is indicated by the solid line. At the BSR occasion 1101, UE1 reports the occupancy level of the buffer. In addition, information 86 indicating the packet arrival rate is provided by UE1, in this example by the quantized values provided in the example of table 2. In response to this, the base station 110 allocates UL resources and informs UE1. The base station 110 is configured to seek to empty the buffer at the earliest possible occasion and allocates resources for this purpose to be used at the UL occasion 1102. In addition, based on the information 86, additional resources are allocated and scheduled for subsequent UL occasions 1103 within the same BSR period before the next BSR 1004. In this example, the base station is configured to allocate an equal amount of resources for each occasion 1103 for data estimated to enter the buffer based on the information 86 after the first occasion 1102 for emptying the buffer based on the BSR 85. In alternative embodiments, a decreasing amount of resources can be scheduled for each UL occasion in the period of 1103.

[0090] Figure 11B The resulting packet delay is shown, which provides for both maximum delay and average delay, against the prior art as well as Figure 10A and Figure 10Bfurther refinement of the embodiments of FIG. 1. The reason for the refinement is quantification: for any value of the obtained packet arrival rate 84, an indication will be determined that represents an upper limit (of the second column of Table 2), and the corresponding indication 86 (including the corresponding value from the first column of Table 2) will be transmitted to the base station 110. Figure 11B The tail of the graph in FIG. 1 is caused by the same effect. Figure 10B

[0091] In an alternative embodiment, a relative representation as shown in Table 3 below is used. This approach means that the information 86 indicating the packet arrival rate can be even smaller in bits. The limits in terms of arrival rate associated with each level can be determined by the base station 110, or alternatively can be provided by a specification.

[0092] Packet arrival rate report Type 00 Nothing to report 01 Slow 10 Medium 11 Fast

[0093] Table 3

[0094] In some embodiments, the information 86 indicating the packet arrival rate includes a flag indicating a delay-sensitive packet transmission. The flag can be implemented as a one-bit value, e.g. 1 or 0 in a binary code. In such embodiments, no explicit packet arrival rate signaling is indicated by the information 86. Instead, the UE 1 indicates that it can have delay-sensitive packets, e.g. by one-bit signaling. If needed, the packet arrival rate can be determined 808 in the base station 110 by a calculation as a function of the buffer size (BS) value and / or the periodicity of the BSR reporting (phr-PeriodicTimer). For example: Max(BS_Value) / phr-PeriodicTimer. If the BSR index is 27, and the BSR periodicity is 10 msec, then it is 55474 / 10, and the rate 84 will be approximately 5K / msec.

[0095] In some embodiments, the information 86 indicating the packet arrival rate includes a time distribution indicator 86A associated with the data in the buffer. In this way, the UE 1 can provide auxiliary information about how the packets are distributed between two BSR occasions, in addition to the packet arrival rate. In conventional operation, the gNB is typically configured to clean the UE buffer by allocating large resources at the beginning of the allocation, as described above. The auxiliary information provided by the time distribution indicator 86A can be configured to indicate one of a plurality of selectable options, e.g. by providing a value of one or more bits. Various options can be:

[0096] Type I: empty the buffer using a first resource occupancy level, and continue the allocation with a second resource occupancy level that is lower than the first resource occupancy level. This corresponds to the allocation of FIG. 1. Figure 10A and Figure 10B and Figure 11A and​Figure 11B The method implemented in the examples provided above. In this way, the base station 110 attempts to first clean the UE buffer, i.e. by allocating a large TB size (as in the conventional approach), and continues to give resource allocations after the resource allocation in the time window for UL transmission associated with the BSR period.

[0097] Type II: Distributed. In this way, the base station 110 can be configured to distribute resource allocations for UL transmissions of the UE buffer 126 and any subsequent data entering the buffer determined based on the information 86 indicating packet arrival rate. In one embodiment, this can include allocating a medium size TB size for each UL occasion in the BSR period until the next BSR.

[0098] Type III: Reverse distribution. This can be seen as a variation of Type II. Based on the BSR 85 and the information 86 indicating packet arrival rate, resources can be specifically allocated at the end of the BSR period. For example, if the BSR 85 indicates a high buffer data level, a large TB size can be allocated at the beginning of the BSR period, however based on the information 86 indicating packet arrival rate, one or more UL occasions can be allocated from the end of the BSR period based on the amount of data expected to enter the buffer in the BSR period. In one variation of this embodiment, a high packet arrival rate indicated by the information 86 can result in UL occasions being allocated starting from the end of the time window of the BSR period, while no resource allocation is provided for the first UL occasion due to the BSR 85 indicating a low data level present in the buffer 126.

[0099] Figure 12A and Figure 12B Figures showing embodiments of Figure 10A , Figure 10B , and Figure 11A and Figure 11B are shown, but where the base station is configured to allocate resources according to the Type III approach described above. According to Figure 10AThe top graph of Figure 1 1 shows the buffer occupancy level indicated by the solid line. At BSR occasion 1201, UE 1 reports the occupancy level of the buffer. In addition, information 86 indicating the packet arrival rate is provided by UE 1, for example by a quantized value, a relative value or a real value. In response thereto, base station 1 10 allocates UL resources and informs UE 1. Due to the high buffer occupancy level, base station 1 10 is configured to seek to empty the buffer 126 at the earliest possible occasion and allocates resources for this purpose to be used at UL occasion 1202. In addition, based on information 86, further resources are allocated and scheduled for a subsequent UL occasion 1203 within the same BSR period before the next BSR 1004. In this embodiment, these occasions are scheduled at the end of the period and, for this purpose, a larger TB is allocated at the last occasion. In the next BSR 1204, the buffer occupancy level of the transmission buffer 126 is lower than in the first BSR 1201, but the packet arrival rate is about the same. Based on the buffer indicated by BSR 85, for example with respect to a threshold level, base station 1 10 will not allocate any initial resources for UL transmission at the beginning 1205 of the associated subsequent period. However, based on information 86 obtained in or with BSR 85, resources are allocated and scheduled for a subsequent UL occasion 1206 at the end of the period.

[0100] Figure 12B The resulting packet count versus packet delay is shown in Figure 1 1, showing that the maximum packet delay and the average packet delay are improved over the conventional approach of the prior art. For specific cases of packet arrival rate, the embodiment does not provide a reference Figure 10A and Figure 10B and Figure 11A and Figure 11B Summary of improvements of the embodiment. However, in case the logical unit 210 of UE 1 knows the packet arrival distribution accurately or approximately from the application providing the data, the embodiment can be most efficient in terms of at least the average delay. Based on such knowledge obtained for example from the application, UE 1 can be configured to selectively transmit an associated time distribution indicator 86A to base station 1 10. Figure 12B The tail of the graph in Figure 1 1 is caused by the same effect as Figure 10B in Figure 1 1.

[0101] In some embodiments, UE 1 can be arranged to transmit a predetermined bit pattern, for example in the UL data, to indicate to base station 1 10 that UE 1 has nothing to send until the next BSR report. This can be achieved for example by transmitting dummy data (e.g. all zeros, all ones) or another specified bit pattern in the allocated uplink resources. Reference can be made to Figure 10AAn example is given. Two first UL occasions at 1002 are provided to empty the buffer based on the BSR 85. Based on information 86 indicating the packet arrival rate, a further UL occasion is allocated at 40 ms. However, even if the arrival rate obtained or determined prior to sending information 86 is at a certain level, the packet arrival rate can actually decrease after the BSR 85 and information 86 are sent. If the refill of the buffer 126 is below a certain level (e.g. compared to a certain threshold), or if the buffer 126 is emptied at the last UL occasion (at 40 ms), this UL occasion can also be used to include the predetermined bit pattern. When the predetermined bit pattern from the UE is detected in one uplink occasion, the base station 110 can be configured to refrain from further resource allocation to the UE until a subsequent BSR period associated with the BSR 1004. This can be beneficial to minimize unnecessary uplink resource allocation, and these resources can instead be allocated to other UEs or other uses.

[0102] Referring back to Figure 8 , various methods can involve the base station 110 allocating 809 resources for UL transmission of the amount of data in the BSR period based on the BSR 85 and information 86 indicating the packet arrival rate, in order to provide resources for both data based on the BSR 85 and data based on an additional amount of data determined from the information 86. In particular, the uplink resources are allocated to match the data identified by the BSR and data determined to refill the buffer in the period based on the information 86 indicating the packet arrival rate, sufficient for UL transmission in the BSR period of the aggregated data. The base station 101 transmits 810 UL resource information 87 to be received 811 in the UE 1, which is allocated based on the BSR and information 86. Thereby, the UE 1 is configured to transmit 812 data using the resource information to be received 813 in the base station 110.

[0103] Various implementations have been outlined above, and they can be combined in any form except where they are mutually contradictory.

Claims

1. A method performed in a user equipment, UE, (1) for controlling uplink transmission of data to a base station (110) of a wireless network (100), the method comprising: transmitting (806) a buffer status report, BSR, (85) indicative of a buffer data level value to the base station; transmitting (806) information (86) indicative of a level of packet arrival rate of data into a transmission buffer to the base station; receiving (811) uplink resource information (87) from the base station in response to the BSR and the information; and transmitting (812) data (88) from the transmission buffer using the received resource information.

2. The method of claim 1, wherein, The information indicative of packet arrival rate is transmitted with the BSR.

3. The method of claim 1 or 2, the method comprising: determining a packet arrival rate at a point in time between transmission of the BSR and a previous BSR.

4. The method of claim 1 or 2, the method comprising: determining the packet arrival rate at the same time as obtaining the buffer data level value.

5. The method of claim 1, wherein, The information indicative of packet arrival rate is selectively transmitted based on BSR control data.

6. The method of claim 5, wherein, The BSR control data depends on an application providing data to the transmission buffer.

7. The method of claim 5, wherein, The BSR control data depends on quality of service, QoS, requirements.

8. The method of any one of claims 5-7, wherein, The BSR control data is determined by the UE.

9. The method of any one of claims 5-7, wherein, The BSR control data is received from the base station.

10. The method of claim 1, wherein, The information indicative of packet arrival rate comprises a packet arrival rate measured by the UE.

11. The method of claim 1, wherein, The information indicative of packet arrival rate comprises a data value representing a quantized level of arrival rate.

12. The method of claim 1, wherein, The information indicative of packet arrival rate comprises a data value representing a relative level of arrival rate.

13. The method of claim 1, wherein, The information indicative of packet arrival rate comprises a flag indicating delay sensitive packet transmission.

14. The method of claim 1, wherein, The information indicative of packet arrival rate comprises a time distribution indicator associated with data in the transmission buffer.

15. The method of claim 1, the method comprising: transmitting a predetermined bit pattern using the received resource information based on the transmission buffer not containing any data scheduled before a subsequent BSR.

16. A method performed in a base station of a wireless network for controlling uplink transmission of data from a user equipment, UE, the method comprising: receiving a buffer status report, BSR, from the UE indicative of a data level value of a transmission buffer of the UE; receiving information from the UE indicative of a level of packet arrival rate of data into the transmission buffer; transmitting uplink resource information allocated in response to the BSR and the information to the UE; and receiving data from the UE transmitted using the uplink resource information. The information indicative of packet arrival rate is received with the BSR.

17. The method of claim 16, wherein, 18. The method of claim 16 or 17, the method comprising: obtaining information associated with data in the transmission buffer; ​ transmitting BSR control data to the UE, in dependence on information associated with the data, to control the UE to transmit the information indicative of packet arrival rate.

19. The method of claim 18, wherein, The BSR control data is dependent on an application providing data to the transmission buffer.

20. The method of claim 18, wherein, The BSR control data is dependent on quality of service, QoS, requirements.

21. The method of claim 16, wherein, The information indicative of packet arrival rate comprises a data value indicative of a measured arrival rate level.

22. The method of claim 16, wherein, The information indicative of packet arrival rate comprises a data value indicative of a quantized arrival rate level.

23. The method of claim 16, wherein, The information indicative of packet arrival rate comprises a data value indicative of a relative arrival rate level.

24. The method of claim 16, wherein, The information indicative of packet arrival rate comprises a 1-bit value, the method further comprising: determining a required allocation based at least on the received BSR and BSR periodicity.

25. The method of claim 16, the method comprising: allocating uplink resources for transmission of an amount of data in a subsequent period based on the BSR and on an additional amount of data determined from the information.

26. The method of claim 25, wherein, The uplink resources are allocated to be sufficient for UL transmission of both data identified by the BSR in the period and data determined to refill the transmission buffer in the period based on the information indicative of packet arrival rate.

27. The method of claim 25 or 26, the method comprising: scheduling uplink occasions based on the amount of data.

28. The method of claim 27, wherein, The scheduling provides distributed uplink occasions allocated based on the BSR and the information.

29. The method of claim 28, wherein, The scheduling provides one or more initial uplink occasions allocated based on the BSR and subsequent one or more uplink occasions for further uplink transmission based on the information.

30. The method of claim 28, wherein, The scheduling provides a uniform distribution of resources to the uplink occasions.

31. The method of claim 29, wherein, The information indicative of packet arrival rate comprises a time distribution indicator associated with data in the transmission buffer, and wherein the scheduling of the uplink occasions is further determined in dependence on the time distribution indicator.

32. The method of claim 26, the method comprising: detecting a predetermined bit pattern in data received from the UE in one uplink occasion; refusing allocation of further resources to the UE until a subsequent BSR period.

33. A UE configured to control uplink transmission of data to a base station of a wireless network, the UE comprising logic configured to control the UE to perform the method of any of claims 1 to 15.

34. A base station of a wireless network configured to control uplink transmission of data from a UE, the base station comprising logic configured to control the base station to perform the method of any of claims 16 to 32.

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