EP3689072A1

EP3689072A1 - Method and apparatus for resource slot configuration and allocating user equipments to resource slots for controlling channel access from the user equipments

Info

Publication number: EP3689072A1
Application number: EP17927655.5A
Authority: EP
Inventors: Markus Mueck; Ingolf Karls; Christian Drewes; Ziad YOUSSEF; Erfan H. MAJEED; Peter Jung; Guido Bruck
Original assignee: Intel IP Corp
Current assignee: Intel Corp
Priority date: 2017-09-29
Filing date: 2017-09-29
Publication date: 2020-08-05
Also published as: EP3689072A4; WO2019066882A1; CN111096031A; CN111096031B

Abstract

Examples provide an access node, a network controller, an apparatus for mobile communication, a mobile communication system, a method and a computer program for an access node or a network controller. A control unit in an access node or a central controller may select a time slot configuration. The channel is divided into a plurality of time slots in time domain in accordance with the selected time slot configuration. Wireless communication devices may be grouped into a plurality of groups based on quality of service (QoS) requirements of the wireless communication devices. A group of wireless communication devices may be allocated to a time slot. The group of wireless communication devices may access the channel using a carrier sense multiple access/collision avoidance (CSMA/CA) mechanism. The control unit may monitor occurrences of events at the wireless communication devices and select a new time slot configuration based on the events.

Description

Method and apparatus for resource slot configuration and allocating user equipments to resource slots for controlling channel access from the user equipments

Field

Examples relate to an access node, a network controller, an apparatus for mobile communication, a mobile communication system, a method and a computer program for an access node or a network controller, and in particular, but not exclusively, to a concept and mechanism for selecting resource slot configuration and allocating user equipments (UEs) to resource slots for controlling channel access from the UEs and interference mitigation.

Background

The Federal Communications Commission (FCC) adopted rules for spectrum sharing techniques (i.e. Spectrum Access System (SAS)) in the 3.55-3.70 GHz band (hereafter "3.5 GHz band"). The 3.55-3.65 GHz band is currently allocated for use by the Department of Defense (DoD) radar systems. This frequency band is suitable for small cell applications. It can be used as an alternative of the existing mobile services or adopted from a primary system to achieve higher coverage and data rates.

The FCC report and order describes the mechanism for using the 3.5 GHz band to provide a service called Citizens Broadband Radio Service (CBRS). The spectrum sharing techniques in the 3.5 GHz band are based on a three-tiered approach (incumbent licensees, priority access (PA) licensees, and general authorized access (GAA) operators). Opening the 3.5 GHz band for sharing can improve the data rate and coverage of existing systems like Long-Term Evolution (LTE), LTE-Advanced, MuLTEfire, Wi-Fi type of systems (all requiring modifications in order to be able to connect to and coordinate with the SAS entity).

The IEEE 802.11 channel access mechanism is based on the distributed coordination function (DCF) using carrier sense multiple access/collision avoidance (CSMA/CA). Fig. 1 shows the IEEE 802.11 medium access control (MAC) structure with different coordination functions. The DCF provides a basic CSMA/CA mechanism for accessing a channel by all devices.

Contention-free services for prioritized access are obtained through the point coordination function (PCF). As shown in Fig. 2, the PCF divides the channel in two periods, a contention free period (CFP) and a contention period (CP). In the CFP, the access point polls a specific station to transmit and the stations get an own time slot to use the channel. In the CP, the contention-based access with CSMA/CA is applied. The hybrid coordination function (HCF) is added in the 802.1 le version of the IEEE 802.11 standards. The HCF includes two types of access methods to access the channel: enhanced distributed channel access (EDCA) and HCF controlled channel access (HCCA). In the EDCA mode, high priority data can be sent more often and a transmit opportunity (TXOP) may be provided to a station where the station can transmit messages several times consecutively. The HCCA is similar to the PCF and uses a CFP and a CP. In the CFP, users are assigned to time slots with a traffic classes (TC). In the CP, the EDCA is applied.

The IEEE 802.11 channel access scheme uses Interframe Spaces (IFS) to prioritize the channel access for different traffic classes or priorities. Fig. 3 shows the relationship between the IFSs. The shorter the IFS, the higher the priority. The DCF uses a Distributed Interframe Space (DIFS), a Short Interframe Space (SIFS), and an Extended Interframe Space (EIFS). The SIFS is be used when devices have seized the medium and need to keep it for the duration of the frame exchange sequence to be performed, (e.g. prior to acknowledgement (ACK) and clear-to-send (CTS) frames). When a station desires to transmit a data frame in a DCF mode, the station needs to wait for the duration of a DIFS after the previous frame's completion. The EIFS value is used by stations that have received a frame containing errors.

The PCF and the HCF use additionally a Priority Interframe Space (PIFS) and an Arbitration Interframe Space (AIFS). The PIFS is used by devices during the CFP in the PCF mode. The AIFS value depends on the access category (AC) and is used to prioritize one AC over another, for example to give a priority to a voice call over an email application. A shorter AIFS period means that a message has a higher probability of being transmitted with low latency. The elementary time unit in the IEEE 802.11 system is a slot time (SlotTime). The slot time is dependent on the physical layer (e.g. propagation time, latencies, or the like). The IFS is measured in units of a slot time. The SIFS value corresponds to the slot time. The values of other IFSs are derived from the specified values of the SIFS and the slot time. Brief description of the Figures

Some examples of apparatuses and/or methods will be described in the following by way of example only, and with reference to the accompanying figures, in which

Fig. 1 shows the IEEE 802.11 MAC structure with different coordination functions; Fig. 2 illustrates switching between a CFP and a CP; Fig. 3 shows the relationship between the IFSs;

Fig. 4 illustrates an example of a wireless communication system;

Fig. 5 illustrates an example control unit that is configured to adaptively set a time slot configuration and allocate UEs or access nodes to the time slots;

Fig. 6 shows an example interaction between a grouping controller and an environment monitor; Fig. 7 shows an example signaling diagram of a process of allocating a UE to a time slot, updating the time slot configuration, and deallocating a UE; and

FIG. 8 illustrates an architecture of a system of a network in accordance with some embodiments.

Detailed Description

Various examples will now be described more fully with reference to the accompanying drawings in which some examples are illustrated. In the figures, the thicknesses of lines, layers and/or regions may be exaggerated for clarity.

Accordingly, while further examples are capable of various modifications and alternative forms, some particular examples thereof are shown in the figures and will subsequently be described in detail. However, this detailed description does not limit further examples to the particular forms described. Further examples may cover all modifications, equivalents, and alternatives falling within the scope of the disclosure. Like numbers refer to like or similar elements throughout the description of the figures, which may be implemented identically or in modified form when compared to one another while providing for the same or a similar functionality.

It will be understood that when an element is referred to as being "connected" or "coupled" to another element, the elements may be directly connected or coupled or via one or more intervening elements. If two elements A and B are combined using an "or", this is to be understood to disclose all possible combinations, i.e. only A, only B as well as A and B. An alternative wording for the same combinations is "at least one of A and B". The same applies for combinations of more than 2 Elements.

The terminology used herein for the purpose of describing particular examples is not intended to be limiting for further examples. Whenever a singular form such as "a," "an" and "the" is used and using only a single element is neither explicitly or implicitly defined as being mandatory, further examples may also use plural elements to implement the same functionality. Likewise, when a functionality is subsequently described as being implemented using multiple elements, further examples may implement the same functionality using a single element or processing entity. It will be further understood that the terms "comprises," "comprising," "includes" and/or "including," when used, specify the presence of the stated features, integers, steps, operations, processes, acts, elements and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, processes, acts, elements, components and/or any group thereof.

Unless otherwise defined, all terms (including technical and scientific terms) are used herein in their ordinary meaning of the art to which the examples belong.

The present disclosure presents examples for providing a capability of learning and implementing an efficient resource slot configuration in a wireless communication network to configure resource slots in which a channel access mechanism can be performed by UEs 410 and an access node 420. The resource slot configuration is a configuration selected by a network (or a device acting or operating as a network device) for dividing a channel into a plurality of resource slots, wherein a UE is assigned to a specific resource slot. The resource slot configuration is adaptable to the QoS requirements of the UEs 410 and/or the network.

The resource slots to which the channel is divided into are defined as time slots, frequency slots, antenna polarization slots, multiple-input multiple-output (MTMO) slots (e.g. one among multiple independent transmission channels corresponding to an eigenmode of the MIMO channel matrix), space slots, or any combination thereof (such as, time/frequency slots, time/space slots, frequency/space slots, time/MIMO slots, time/frequency /MIMO slots, time/frequency/space slots, etc.). Hereafter, the examples will be explained with reference to "time slots." However, it should be noted that the examples are not limited to time slots, but are equally applicable to different types of resource slots.

The channel access mechanism implemented by UEs 410 and access nodes 420 may be a distributed channel access mechanism or any other types of channel access mechanism. For example, the channel access mechanism may be CSMA/CA. Hereafter, the examples will be explained with reference to CSMA/CA. However, it should be noted that the examples are not limited to CSMA/CA, but are equally applicable to different types of channel access mechanisms. In the examples disclosed hereafter, the term "QoS requirements" (and the associated "QoS" accordingly) will be used to include any requirements that a UE may request for the network or any measures or criteria that a UE's or network's performance or experience may be evaluated for, and may not necessarily be tied to a service itself. For examples, the "QoS requirements" may be throughput requirements, delay requirements, access rate requirements, collision requirements, interference requirements, power efficiency requirements, subscription type-related requirements (e.g. requirements according to more or less costly service contracts, etc.), or the like.

Conventional end device grouping and allocations schemes (e.g. for Internet-of-things (IoT)) do not provide a self-organized, runtime adaptive time slot allocation/configuration scheme in terms of QoS, where several CSMA/CA-based devices may operate to fulfill certain criteria. In addition, the conventional end device grouping schemes are implemented open loop and interfere with channel access requirements of the end devices. According to the examples disclosed herein, the overall efficiency and flexibility for network and user demands is substantially increased.

According to the examples disclosed herein, the grouping controller is capable of learning the environment and using the collected real-time knowledge and environment behavior for decision making. The grouping function is implemented to find an optimal end device-to-slot allocation mapping to perform fair coexistence between the end devices with different QoS requirements and to reach an optimal interaction between the end devices which are using different operation modes (e.g. the IEEE 802.1 1 EDCA mode influences the DCF mode due to short contention windows). The grouping controller with deep learning capabilities can provide an optimal end device assignment to the time slot to achieve fair coexistence between the end devices with different QoS requirements and different operation modes.

Fig. 4 illustrates an example of a wireless communication system 400. Examples provide a wireless communication system 400 including a plurality of user equipments (UEs) 410 and one or more access nodes 420. A further example is a wireless communication system 400 including a plurality of UEs 410, one or more access nodes 420, and a central controller 430 for controlling the access node(s) 420 and/or the UEs 410. A UE 410 is a wireless communication device used by a user. The UEs 410 implement CSMA/CA for accessing a channel in the wireless communication system 400. As CSMA/CA may be used as an access scheme for the UE 410, the wireless communication system 400 may implement, for example, WiFi, licensed assisted access (LAA), MuLTEfire, or the like. A UE 410 may be, or may be included in, a mobile terminal, a mobile transceiver, a smartphone, a cell phone, a station, a laptop, a notebook, a personal computer, a tablet computer, a Personal Digital Assistant (PDA), a Universal Serial Bus (USB) stick, a car, or any other type of device having wireless transmission/reception capabilities.

An access node 420 is a network device operable to communicate with one or more UEs 410 in a coverage area (e.g., a cell) covered by the access node 420. An access node 420 may control the channel access by the UEs 410 in a coverage area of the access node 420. The coverage area of an access node 420 may be a macro cell or a small cell (such as a pico cell, a metro cell, a femto cell, a micro cell, a nano cell, or the like). The access nodes 420 may be in or adjacent to a coverage area of other access nodes (e.g. a small cell access node located in a coverage area of a macro cell access node). The access nodes 420 may be located in the fixed or stationary part of the system 400. The access nodes 420 may belong to the same category or to different categories. Access nodes 420 in different categories may have different priorities in accessing a channel in the network. For example, the access nodes 420 may be a tier-2 device or a tier-3 device in the SAS system. The access nodes 420 may also implement CSMA/CA for accessing a channel and controlling the accesses from the UEs 410. The access node 420 may be a base station, a base station transceiver, a (e)NodeB, a home (e)NodeB, an access point, a Citizens Broadband Radio Service Device (CBSD), a remote radio head, a relay node, a transmission point, a SAS controller, or the like, which may be further divided into a remote unit and a central unit. In some examples, a UE 410 may act or operate as an access node 420 (e.g. a smartphone operating as an AP or as a CBSD, etc.), and the functions implemented in an access node 420 in the examples disclosed herein may be implemented in a UE 410 as well. The central controller 430 is a network controller (i.e. a network entity) that may interact (either via a wireless connection or a wired connection) with one or more access nodes 420 for managing the system. There may be more than one central controller in the system 400 and each central controller may interact with a different set of access nodes. The central controller 430 may perform functions for access control from the UEs 410 or implement measures for interference mitigation in the coverage areas, or the like. The central controller 430 may be a stand-alone controller or may be incorporated into another network entity. The central controller 430 may be located in a core network of a macro area mobile network (e.g. a Third Generation (3G) or Fourth Generation (4G) core network) or may be external to the core network. The central controller 430 may be a SAS controller provided for incumbent protection and spectrum allocation in the SAS system.

Any of the radio links between entities/devices of the wireless communication system 400 may operate according to any one or more of the following radio communication technologies and/or standards including, but not limited to: a Global System for Mobile Communications (GSM) radio communication technology, a General Packet Radio Service (GPRS) radio communication technology, an Enhanced Data Rates for GSM Evolution (EDGE) radio communication technology, and/or a Third Generation Partnership Project (3GPP) radio communication technology, for example Universal Mobile Telecommunications System (UMTS), Freedom of Multimedia Access (FOMA), 3 GPP Long Term Evolution (LTE), 3 GPP Long Term Evolution Advanced (LTE Advanced), Code division multiple access 2000 (CDMA2000), Cellular Digital Packet Data (CDPD), Mobitex, Third Generation (3G), Circuit Switched Data (CSD), High-Speed Circuit- Switched Data (HSCSD), Universal Mobile Telecommunications System (Third Generation) (UMTS (3G)), Wideband Code Division Multiple Access (Universal Mobile Telecommunications System) (W-CDMA (UMTS)), High Speed Packet Access (HSPA), High-Speed Downlink Packet Access (HSDPA), High-Speed Uplink Packet Access (HSUPA), High Speed Packet Access Plus (HSPA+), Universal Mobile Telecommunications System-Time-Division Duplex (UMTS- TDD), Time Division-Code Division Multiple Access (TD-CDMA), Time Division- Synchronous Code Division Multiple Access (TD-CDMA), 3rd Generation Partnership Project Release 8 (Pre-4th Generation) (3 GPP Rel. 8 (Pre-4G)), 3 GPP Rel. 9 (3rd Generation Partnership Project Release 9), 3GPP Rel. 10 (3rd Generation Partnership Project Release 10) , 3 GPP Rel. 11 (3rd Generation Partnership Project Release 11), 3 GPP Rel. 12 (3rd Generation Partnership Project Release 12), 3GPP Rel. 13 (3rd Generation Partnership Project Release 13), 3 GPP Rel. 14 (3rd Generation Partnership Project Release 14), 3 GPP Rel. 15 (3rd Generation Partnership Project Release 15), 3GPP Rel. 16 (3rd Generation Partnership Project Release 16), 3GPP Rel. 17 (3rd Generation Partnership Project Release 17), 3GPP Rel. 18 (3rd Generation Partnership Project Release 18), 3 GPP 5G, 3 GPP LTE Extra, LTE- Advanced Pro, LTE Licensed- Assisted Access (LAA), MuLTEfire, UMTS Terrestrial Radio Access (UTRA), Evolved UMTS Terrestrial Radio Access (E-UTRA), Long Term Evolution Advanced (4th Generation) (LTE Advanced (4G)), cdmaOne (2G), Code division multiple access 2000 (Third generation) (CDMA2000 (3G)), Evolution-Data Optimized or Evolution- Data Only (EV-DO), Advanced Mobile Phone System (1st Generation) (AMPS (1G)), Total Access Communication System/Extended Total Access Communication System (TACS/ETACS), Digital AMPS (2nd Generation) (D-AMPS (2G)), Push-to-talk (PTT), Mobile Telephone System (MTS), Improved Mobile Telephone System (IMTS), Advanced Mobile Telephone System (AMTS), OLT (Norwegian for Offentlig Landmobil Telefoni, Public Land Mobile Telephony), MTD (Swedish abbreviation for Mobiltelefonisystem D, or Mobile telephony system D), Public Automated Land Mobile (Autotel/PALM), ARP (Finnish for Autoradiopuhelin, "car radio phone"), NMT (Nordic Mobile Telephony), High capacity version of NTT (Nippon Telegraph and Telephone) (Hicap), Cellular Digital Packet Data (CDPD), Mobitex, DataTAC, Integrated Digital Enhanced Network (iDEN), Personal Digital Cellular (PDC), Circuit Switched Data (CSD), Personal Handy-phone System (PHS), Wideband Integrated Digital Enhanced Network (WiDEN), iBurst, Unlicensed Mobile Access (UMA), also referred to as also referred to as 3 GPP Generic Access Network, or GAN standard), Zigbee, Bluetooth®, Wireless Gigabit Alliance (WiGig) standard, mmWave standards in general (wireless systems operating at 10-300 GHz and above such as WiGig, IEEE 802. Had, IEEE 802. Hay, etc.), IEEE 802.11 standards in general including 802.11a, 802.1 lb, 802.1 lg, 802.1 In, and 802.1 lac, technologies operating above 300 GHz and THz bands, (3GPP/LTE based or IEEE 802.1 lp and other) Vehicle-to-Vehicle (V2V) and Vehicle- to-X (V2X) communication technologies, DSRC (Dedicated Short Range Communications) communication systems such as Intelligent-Transport-Systems and others, etc. Moreover, the wireless communication system 400 may be used or operated in the context of any spectrum management scheme including dedicated licensed spectrum, unlicensed spectrum, (licensed) shared spectrum (such as Licensed Shared Access (LSA) in 2.3-2.4 GHz, 3.4-3.6 GHz, 3.6-3.8 GHz and further frequencies and Spectrum Access System (SAS) in 3.55-3.7 GHz and further frequencies). Applicable spectrum bands include International Mobile Telecommunications (IMT) spectrum (including 450 - 470 MHz, 790 - 960 MHz, 1710 - 2025 MHz, 2110 - 2200 MHz, 2300 - 2400 MHz, 2500 - 2690 MHz, 698-790 MHz, 610 - 790 MHz, 3400 - 3600 MHz, etc.). Note that some bands are limited to specific region(s) and/or countries), IMT-advanced spectrum, IMT-2020 spectrum (expected to include 3600-3800 MHz, 3.5 GHz bands, 700 MHz bands, bands within the 24.25-86 GHz range, etc.), spectrum made available under FCC's "Spectrum Frontier" 5G initiative (including 27.5 - 28.35 GHz, 29.1 - 29.25 GHz, 31 - 31.3 GHz, 37 - 38.6 GHz, 38.6 - 40 GHz, 42 - 42.5 GHz, 57 - 64 GHz, 64 - 71 GHz, 71 - 76 GHz, 81 - 86 GHz and 92 - 94 GHz, etc), the ITS (Intelligent Transport Systems) band of 5.9 GHz (typically 5.85-5.925 GHz) and 63-64 GHz, bands currently allocated to WiGig such as WiGig Band 1 (57.24- 59.40 GHz), WiGig Band 2 (59.40-61.56 GHz) and WiGig Band 3 (61.56-63.72 GHz) and WiGig Band 4 (63.72-65.88 GHz), the 70.2 GHz - 71 GHz band, any band between 65.88 GHz and 71 GHz, bands currently allocated to automotive radar applications such as 76-81 GHz, and future bands including 94-300 GHz and above. Furthermore, the scheme can be used on a secondary basis on bands such as the TV White Space bands (typically below 790 MHz) where in particular the 400 MHz and 700 MHz bands are promising candidates. Besides cellular applications, specific applications for vertical markets may be addressed such as Program Making and Special Events (PMSE), medical, health, surgery, automotive, low- latency, drones, etc. applications. A hierarchical application of the scheme is possible, e.g. by introducing a hierarchical prioritization of usage for different types of users (e.g., low/medium/high priority, etc.), based on a prioritized access to the spectrum e.g. with highest priority to tier- 1 users, followed by tier-2, then tier-3, etc. users, etc. In the disclosed examples, other hierarchical approaches are also possible. Examples may also be applied to different Single Carrier or orthogonal frequency division multiplex (OFDM) flavors (cyclic prefix OFDM (CP-OFDM), single carrier frequency division multiple access (SC-FDMA), single carrier OFDM (SC-OFDM), filter bank-based multicarrier (FBMC), orthogonal frequency division multiple access (OFDMA), etc.) and in particular 3 GPP NR (New Radio) by allocating the OFDM carrier data bit vectors to the corresponding symbol resources. In vehicular communications (such as IEEE 802.1 lp, LTE C-V2X, V2V (Vehicle-to-Vehicle), V2I (Vehicle-to-Infrastructure), V2P (Vehicle-to- Person), etc. communications) or other safety related contexts, a priority user may relate to "safety related applications" users while the non-priority users may relate to "non-safety related applications". Some examples may provide protection of priority users - in order to protect the correct operation of such safety related applications. Non-safety applications are less critical and a failure may be tolerated. The same scheme may be employed for any prioritization of "higher priority applications" vs "lower priority applications" in the vehicular communications context or any other context. In some examples the protection can be in three dimensions. For example, if the spectrum is shared with satellites, drones, or other objects moving above ground, the sky above a certain altitude (including the satellite special slots) would become a priority area or zone and the interference to satellites due to terrestrial communication might be reduced or even minimized. Here, it may be sufficient in some examples to impose suitable antenna patterns such that emissions remain in the terrestrial space and do not radiate into space. If the multipath/scattering environment becomes too challenging for some users (at least some emission power may always radiate towards the satellite), this user may be forced to reduce its output power levels, to switch to another frequency band or similar. Examples disclosed herein may be applied to the case where a central entity (e.g. a SAS controller in CBRS/SAS, an LSA controller in LSA, or the like) exists. Examples disclosed herein may be applied to systems other than spectrum sharing systems if a central entity is available to execute the coordination tasks. The functionalities of the access node 420 (e.g. a CBRS/SAS/LSA CBSD, AP, eNodeB, etc.) may be located in a dedicated component (such as a dedicated CBSD, AP, eNodeB, etc.) or may be part of any other device including a UE (e.g. a UE may take a role of a CBRS/SAS/LSA CBSD, AP, eNodeB, etc., for example in the CBSD/SAS tier-3 mode where the system operates similar to unlicensed systems such as WiFi, MuLTEfire, etc.).

FIG. 8 illustrates an architecture of a system 800 of a network in accordance with some embodiments. The system 800 is shown to include a user equipment (UE) 801 and a UE 802. The UEs 801 and 802 are illustrated as smartphones (e.g., handheld touchscreen mobile computing devices connectable to one or more cellular networks), but may also comprise any mobile or non-mobile computing device, such as Personal Data Assistants (PDAs), pagers, laptop computers, desktop computers, wireless handsets, or any computing device including a wireless communications interface.

In some embodiments, any of the UEs 801 and 802 can comprise an Internet of Things (IoT) UE, which can comprise a network access layer designed for low-power IoT applications utilizing short-lived UE connections. An IoT UE can utilize technologies such as machine- to-machine (M2M) or machine-type communications (MTC) for exchanging data with an MTC server or device via a public land mobile network (PLMN), Proximity-Based Service (ProSe) or device-to-device (D2D) communication, sensor networks, or IoT networks. The M2M or MTC exchange of data may be a machine-initiated exchange of data. An IoT network describes interconnecting IoT UEs, which may include uniquely identifiable embedded computing devices (within the Internet infrastructure), with short-lived connections. The IoT UEs may execute background applications (e.g., keep-alive messages, status updates, etc.) to facilitate the connections of the IoT network.

The UEs 801 and 802 may be configured to connect, e.g., communicatively couple, with a radio access network (RAN) 810 - the RAN 810 may be, for example, an Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E- UTRAN), a NextGen RAN (NG RAN), or some other type of RAN. The UEs 801 and 802 utilize connections 803 and 804, respectively, each of which comprises a physical communications interface or layer (discussed in further detail below); in this example, the connections 803 and 804 are illustrated as an air interface to enable communicative coupling, and can be consistent with cellular communications protocols, such as a Global System for Mobile Communications (GSM) protocol, a code-division multiple access (CDMA) network protocol, a Push-to-Talk (PTT) protocol, a PTT over Cellular (POC) protocol, a Universal Mobile Telecommunications System (UMTS) protocol, a 3GPP Long Term Evolution (LTE) protocol, a fifth generation (5G) protocol, a New Radio (NR) protocol, and the like. In this embodiment, the UEs 801 and 802 may further directly exchange communication data via a ProSe interface 805. The ProSe interface 805 may alternatively be referred to as a sidelink interface comprising one or more logical channels, including but not limited to a Physical Sidelink Control Channel (PSCCH), a Physical Sidelink Shared Channel (PSSCH), a Physical Sidelink Discovery Channel (PSDCH), and a Physical Sidelink Broadcast Channel (PSBCH).

The UE 802 is shown to be configured to access an access point (AP) 806 via connection 807. The connection 807 can comprise a local wireless connection, such as a connection consistent with any IEEE 802.11 protocol, wherein the AP 806 would comprise a wireless fidelity (WiFi®) router. In this example, the AP 806 is shown to be connected to the Internet without connecting to the core network of the wireless system (described in further detail below).

The RAN 810 can include one or more access nodes that enable the connections 803 and 804. These access nodes (ANs) can be referred to as base stations (BSs), NodeBs, evolved NodeBs (eNBs), next Generation NodeBs (gNB), RAN nodes, and so forth, and can comprise ground stations (e.g., terrestrial access points) or satellite stations providing coverage within a geographic area (e.g., a cell). The RAN 810 may include one or more RAN nodes for providing macrocells, e.g., macro RAN node 811, and one or more RAN nodes for providing femtocells or picocells (e.g., cells having smaller coverage areas, smaller user capacity, or higher bandwidth compared to macrocells), e.g., low power (LP) RAN node 812.

Any of the RAN nodes 811 and 812 can terminate the air interface protocol and can be the first point of contact for the UEs 801 and 802. In some embodiments, any of the RAN nodes 811 and 812 can fulfill various logical functions for the RAN 810 including, but not limited to, radio network controller (RNC) functions such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management. In accordance with some embodiments, the UEs 801 and 802 can be configured to communicate using Orthogonal Frequency-Division Multiplexing (OFDM) communication signals with each other or with any of the RAN nodes 811 and 812 over a multicarrier communication channel in accordance various communication techniques, such as, but not limited to, an Orthogonal Frequency-Division Multiple Access (OFDMA) communication technique (e.g., for downlink communications) or a Single Carrier Frequency Division Multiple Access (SC-FDMA) communication technique (e.g., for uplink and ProSe or sidelink communications), although the scope of the embodiments is not limited in this respect. The OFDM signals can comprise a plurality of orthogonal subcarriers.

In some embodiments, a downlink resource grid can be used for downlink transmissions from any of the RAN nodes 811 and 812 to the UEs 801 and 802, while uplink transmissions can utilize similar techniques. The grid can be a time-frequency grid, called a resource grid or time-frequency resource grid, which is the physical resource in the downlink in each slot. Such a time-frequency plane representation is a common practice for OFDM systems, which makes it intuitive for radio resource allocation. Each column and each row of the resource grid corresponds to one OFDM symbol and one OFDM subcarrier, respectively. The duration of the resource grid in the time domain corresponds to one slot in a radio frame. The smallest time-frequency unit in a resource grid is denoted as a resource element. Each resource grid comprises a number of resource blocks, which describe the mapping of certain physical channels to resource elements. Each resource block comprises a collection of resource elements; in the frequency domain, this may represent the smallest quantity of resources that currently can be allocated. There are several different physical downlink channels that are conveyed using such resource blocks.

The physical downlink shared channel (PDSCH) may carry user data and higher-layer signaling to the UEs 801 and 802. The physical downlink control channel (PDCCH) may carry information about the transport format and resource allocations related to the PDSCH channel, among other things. It may also inform the UEs 801 and 802 about the transport format, resource allocation, and H-ARQ (Hybrid Automatic Repeat Request) information related to the uplink shared channel. Typically, downlink scheduling (assigning control and shared channel resource blocks to the UE 102 within a cell) may be performed at any of the RAN nodes 811 and 812 based on channel quality information fed back from any of the UEs 801 and 802. The downlink resource assignment information may be sent on the PDCCH used for (e.g., assigned to) each of the UEs 801 and 802.

The PDCCH may use control channel elements (CCEs) to convey the control information. Before being mapped to resource elements, the PDCCH complex- valued symbols may first be organized into quadruplets, which may then be permuted using a sub-block interleaver for rate matching. Each PDCCH may be transmitted using one or more of these CCEs, where each CCE may correspond to nine sets of four physical resource elements known as resource element groups (REGs). Four Quadrature Phase Shift Keying (QPSK) symbols may be mapped to each REG. The PDCCH can be transmitted using one or more CCEs, depending on the size of the downlink control information (DCI) and the channel condition. There can be four or more different PDCCH formats defined in LTE with different numbers of CCEs (e.g., aggregation level, L=l, 2, 4, or 8). Some embodiments may use concepts for resource allocation for control channel information that are an extension of the above-described concepts. For example, some embodiments may utilize an enhanced physical downlink control channel (EPDCCH) that uses PDSCH resources for control information transmission. The EPDCCH may be transmitted using one or more enhanced the control channel elements (ECCEs). Similar to above, each ECCE may correspond to nine sets of four physical resource elements known as an enhanced resource element groups (EREGs). An ECCE may have other numbers of EREGs in some situations. The RAN 810 is shown to be communicatively coupled to a core network (CN) 820— via an S 1 interface 813. In embodiments, the CN 820 may be an evolved packet core (EPC) network, a NextGen Packet Core (NPC) network, or some other type of CN. In this embodiment the SI interface 813 is split into two parts: the Sl-U interface 814, which carries traffic data between the RAN nodes 811 and 812 and the serving gateway (S-GW) 822, and the Sl- mobility management entity (MME) interface 815, which is a signaling interface between the RAN nodes 811 and 812 and MMEs 821. In this embodiment, the CN 820 comprises the MMEs 821, the S-GW 822, the Packet Data Network (PDN) Gateway (P-GW) 823, and a home subscriber server (HSS) 824. The MMEs 821 may be similar in function to the control plane of legacy Serving General Packet Radio Service (GPRS) Support Nodes (SGSN). The MMEs 821 may manage mobility aspects in access such as gateway selection and tracking area list management. The HSS 824 may comprise a database for network users, including subscription-related information to support the network entities' handling of communication sessions. The CN 820 may comprise one or several HSSs 824, depending on the number of mobile subscribers, on the capacity of the equipment, on the organization of the network, etc. For example, the HSS 824 can provide support for routing/roaming, authentication, authorization, naming/addressing resolution, location dependencies, etc.

The S-GW 822 may terminate the SI interface 813 towards the RAN 810, and routes data packets between the RAN 810 and the CN 820. In addition, the S-GW 822 may be a local mobility anchor point for inter-RAN node handovers and also may provide an anchor for inter-3GPP mobility. Other responsibilities may include lawful intercept, charging, and some policy enforcement.

The P-GW 823 may terminate an SGi interface toward a PDN. The P-GW 823 may route data packets between the EPC network 823 and external networks such as a network including the application server 830 (alternatively referred to as application function (AF)) via an Internet Protocol (IP) interface 825. Generally, the application server 830 may be an element offering applications that use IP bearer resources with the core network (e.g., UMTS Packet Services (PS) domain, LTE PS data services, etc.). In this embodiment, the P-GW 823 is shown to be communicatively coupled to an application server 830 via an IP communications interface 825. The application server 830 can also be configured to support one or more communication services (e.g., Voice-over-Internet Protocol (VoIP) sessions, PTT sessions, group communication sessions, social networking services, etc.) for the UEs 801 and 802 via the CN 820.

The P-GW 823 may further be a node for policy enforcement and charging data collection. Policy and Charging Enforcement Function (PCRF) 826 is the policy and charging control element of the CN 820. In a non-roaming scenario, there may be a single PCRF in the Home Public Land Mobile Network (HPLMN) associated with a UE's Internet Protocol Connectivity Access Network (IP-CAN) session. In a roaming scenario with local breakout of traffic, there may be two PCRFs associated with a UE's IP-CAN session: a Home PCRF (H-PCRF) within a HPLMN and a Visited PCRF (V-PCRF) within a Visited Public Land Mobile Network (VPLMN). The PCRF 826 may be communicatively coupled to the application server 830 via the P-GW 823. The application server 830 may signal the PCRF 826 to indicate a new service flow and select the appropriate Quality of Service (QoS) and charging parameters. The PCRF 826 may provision this rule into a Policy and Charging Enforcement Function (PCEF) (not shown) with the appropriate traffic flow template (TFT) and QoS class of identifier (QCI), which commences the QoS and charging as specified by the application server 830.

Referring again to Fig. 4, in some examples, the access node 420 or the central controller 430 selects a time slot configuration (more generally, a resource slot configuration), wherein a channel is divided into a plurality of time slots in time domain in accordance with the selected time slot configuration. As stated above, the examples will be explained with reference to time slot and time slot configuration, but the examples are equally applicable to any type of resource slots and resource slot configuration schemes. The channel may be defined with a plurality of elementary time units (e.g. SlotTimes) in time domain, and each time slot may comprise one or more elementary time units. In a first time slot configuration, the communication channel is divided into time slots in a first manner, while in a second time slot configuration, the communication channel is divided into time slots in a different second manner. For example, in the first time slot configuration, a given time period corresponds to a first number of time slots, while in the second time slot configuration the same time period corresponds to a different second number of time slots. In the first time slot configuration, a first time slot (of a sequence of time slots) may comprise a first number of elementary time units, while in the second time slot configuration the first time slot may comprise a different second number of elementary time units.

The access node 420 (either acting alone or under the control of the central controller 430, or a UE 410 acting as an access node or as a CBSD, etc.) may group UEs 410 into a plurality of groups based on QoS requirements of the UEs 410, and allocate a group of UEs 410 to a time slot(s). The group of UEs 410 may access the channel using a CSMA/CA mechanism (more generally, any channel access mechanism). As stated above, the examples will be explained with reference to CSMA/CA, but the examples are equally applicable to any type of channel access mechanisms. The group of UEs 410 may compete for the channel in the allocated time slot or time slots. If a UE 410 gains an access to the channel (e.g., by implementing the CSMA/CA mechanism), the UE 410 may initiate transmission of frames. The access node 420 or the central controller 430 may be capable of learning the environment and using it, for example, for making a decision regarding time slot configuration, influencing the access duration of the UEs (e.g. Tier-3 users of the SAS system) to the spectrum based on predetermined criteria, and reducing the level of channel access requests by the access nodes or the UEs using time slot allocation, such that the resource usage and system efficiency may be improved. For example, the channel access by the UEs 410 within the allocated time slot using a CSMA/CA mechanism may be controlled by the access nodes 420 or the central controller 430 adaptively based on QoS requirements such as throughput, delay, access rate, collision, interference, power efficiency, subscription type-related requirements, or the like.

Fig. 5 illustrates an example control unit 510 that is configured to adaptively set a time slot configuration and allocate UEs 410 or access nodes 420 to the time slots. The control unit 510 may include a grouping controller 610 and an environment monitor 620, which will be explained in detail with respect to Fig. 6. The control unit 510 interacts with the TDMA- CSMA/CA function 520 to adaptively configuring time slots and allocating UEs 410 or access nodes 420 to the time slots in different network situations based on certain criteria. In this example, the control unit 510 initially selects the time slot configuration (CI) as shown on the left side of Fig. 5, and later changes to the time slot configuration (C2) as shown on the right side of Fig. 5 based on the changed network situation. The control unit 510 may consider certain criteria such as QoS requirements of the UEs (e.g. collision requirements or delay requirements of the UEs), an interference level experienced on the channel, the number of UEs or access nodes in the system, or the like in determining the time slot configuration and allocating the UEs 410 or access nodes 420 to the time slots. It is well known that the efficiency of the CSMA/CA mechanism is decreased substantially with higher channel traffic. In accordance with the channel allocation scheme of the examples disclosed herein, the offered channel traffic will be reduced due to the reduced contention participants and therefore the efficiency of the CSMA/CA mechanism will be increased. The control unit 510 can be a software module configured to perform the functions in accordance with the examples disclosed herein, including determining the time slot configuration and allocation of UEs 410 to time slots based on certain criteria to maximize performance in the wireless communication system 400. In examples, the control unit 510 may be implemented using one or more processing units, one or more processing devices, any means for processing, any means for determining, any means for calculating, such as a processor, a computer or a programmable hardware component being operable with accordingly adapted software. In other words, the described functions of the control unit 510 may as well be implemented in software, which is then executed on one or more programmable hardware components. Such hardware components may comprise a general purpose processor, a Digital Signal Processor (DSP), a micro-controller, etc.

In one example, the control unit 510 may be included in the access node 420 and the access node 420 may implement the time slot configuration and UE allocation based on certain criteria, i.e. the control unit 510 is included in the access node 420 such that the access node 420 makes the time slot configuration and allocation decision for the UEs 410 that are connected to, or request a connection to, the access node 420. The control unit 510 in the access node 420 may select and reselect the time slot configuration and allocate UEs 410 to the time slots adaptably based on the QoS requirements of the UEs 410 or the network. The criteria that the control unit 510 may consider includes, but is not limited to, throughput, data rate, collision, latency, robustness, network topology, interference, or the like.

The control unit 510 may also determine whether the UEs 410 assigned to a time slot can access the channel without contention or through contention, for example, based on the number of UEs assigned to a time slot. For example, if more UEs (e.g. the number of UEs is more a threshold) are assigned to the same time slot the UEs may access the channel through contention and if less UEs (e.g. the number of UEs is equal to or less than a threshold) are assigned to the same time slot, the UEs may access the channel without contention. The duration of the time slot may depend on QoS requirements of UEs 410 allocated to the time slot. For example, UEs 410 with high QoS requirements may be allocated to a longer time slot (comprising more elementary time units) and UEs 410 with low QoS requirements may be allocated to a shorter time slot (comprising less elementary time units). Rejected UEs (e.g., through a reject request-to-send (RRTS) message by an access point) may be allocated with the UEs 410 with a low QoS requirement. For example, UEs 410 may be given different priorities based on a subscription status of the UEs 410, and may be allocated to a different time slot based on the subscription-based priorities. In one example, the time slots may be classified based on their QoS requirements, for example low QoS requirement slots and high QoS requirement slots. For example, UEs previously rejected by an access node may be distributed over the low QoS requirement slots to avoid performance degradation on the high QoS requirement slots.

In another example, to solve the hidden node problem, allocation of UEs 410 to time slots may be based on the spatial distribution between the UEs 410. For example, UEs 410 geographically separated further may be allocated to different time slots. With this scheme, the contention-based access can be improved because the contention window size can be decreased due to reduction of competition in a time slot.

In still another examples, UEs with a specific QoS requirement below a pre-determined threshold and UEs with the specific QoS requirement equal to or above the pre-determined threshold may be grouped separately and allocated to different time slots. In another example, UEs with a specific QoS requirement are grouped separately and allocated in a separate time slot. For example, the specific QoS requirement may be a collision requirement or a delay requirement.

In accordance with another example, the control unit 510 may be included in the central controller 430 and the central controller 430 may implement the time slot configuration and allocation. For example, the central controller 430 may set the time slot configuration and allocate access nodes 420 to time slots based on certain criteria. In this example, the access nodes 420 may access the channel in the allocated time slot. The central controller 430 (e.g. the SAS controller) may implement this method for interference mitigation between access nodes.

In determining time slot configuration and allocation of access nodes 420 to time slots, the control unit 510 may consider spatial distribution of the access nodes 420, coverage of the access nodes 420, priority of the access nodes 420, or the like. For example, the control unit 510 may allocate access nodes 420 that are closely located to each other to different time slots to avoid interference, and allocate access nodes 420 located closely but having a small coverage area or access nodes 420 that are spaced far apart to the same time slot. For some QoS requirements, there may be a certain number of suitable configuration schemes Cm to improve the performance. In examples, the adaptation is built in a manner that allows the allocation of different time slots for a certain group of access nodes 420 or UEs 410.

As disclosed above, the channel is divided into a plurality of time slots wherein each time slot comprises one or more elementary time units in the system. There may be several potential time slot configurations which can be used to fulfill certain QoS requirement s). The time slot configuration may be selected or determined by adapting different QoS requirements in runtime. The time slot configuration (C_m) that provides an optimal or better results to fulfil a certain QoS criteria may be selected among a plurality of possible time slot configurations (C). In accordance with one example, the time slot configuration may be selected or determined to find the optimal policy that maximizes the reward as follows: where the state s describes the required criterion (e.g. collision, latency, throughput, interference, access rate, or the like), the action a is a selection of a particular time slot configuration (C_m) among a plurality of possible time slot configurations (C), and r is a reward. The action-value function Q outputs the reward achievable by the selected action a for the state s. The action- value function Q may specify the long-term value for an action a. The above maximization of the action-value function Q formulates the goal of finding the action with the best value (or gain).

In one example, the reward r may be evaluated as follows:

The parameter β may be chosen depending on a specific QoS criterion. For example, the parameter β may be the number of collisions occurred, a delayed time for channel access, a throughput experienced by the UEs, an interference level, an access rate, or the like. The parameter βΐ is the maximum value of β and β2 is the minimum value of β that may cover the whole dynamic range of the parameter β. The parameter β₀ and β₃ (β₀ and β₃ may be the same value or different values) represents the bounds for evaluating β as good or bad. In case where the dynamic range of the parameter β is unknown, the reward may be defined as follows:

For example, with a collision requirement, the reward will be +1 when the number of collisions occurred is below a certain threshold and -1 when the number of collisions occurred is above a threshold. The action (e.g. selection of a particular time slot configuration) may be performed with the one that results in the greatest reward.

In accordance with another example, to be able to adapt different QoS requirements and evaluate them, the measurements may be made in a general way, which combines several quantities in one parameter. For example, the reward r may be measured in terms of occurrences of events (E). An event is caused at a UE 410 when a QoS requirement is not met at the UE 410. For example, an event occurs when a UE 410 experiences a collision when accessing a channel using CSMA/CA. Alternatively, an event may occur when a UE 410 experiences a delay in accessing a channel more than a pre-determined threshold. An event may be caused at UEs 410 for different QoS requirements as well. When a UE 410 could not obtain the required QoS (e.g. collision, latency, throughput, or the like) an event is caused, and the events of all UEs 410 are collected. In this way, several requirements can be combined in an abstract way to make the evaluation more efficiently.

Depending on the state s and the action a, the reward r may be evaluated as follows:

The reward r_t corresponds with the event changes from the previous evaluation. The best action (e.g. time slot configuration) may be the one that results in the lowest events.

To evaluate the action based on the reward r_t, the function Q outputs, i.e. the reward (e.g. the monitored QoS occurred at the UEs) achievable by the selected action a for the state s, may be accumulated using a learning method as follows: The parameter a is a learning rate that affects the speed of learning and may be used to adjust the convergence and stability of the optimization process.

To simplify the search of the optimal policy among a plurality of potential time slot configurations, a look up table resulting from the learning method may be used to evaluate the actions. Table 1 is an example look-up table that may be used to evaluate the actions a_t based on the Q_t values.

As an example, it is assumed that there are 4 actions

where C_k is the k-th configuration, with the rewards as given in Table 2.

Table 2

For example, the optimization process may proceed as follows (wherein for each iteration, the table is updated to illustrate the evolution of Q, with a learning rate of 0.5):

Iteration 1 :

Iteration 2: Action a_t: a₃

Iteration 3 :

Iteration 4: Action a_t: a₂

Iteration 5: Action a_t: a_t

Iteration 6

Action at. a₂

Since in this example the configurations CO and C3 would give the best reward, it will dominate after some iterations and determine the stationary operation C_m of the system as defined as follows: where is the policy to follow.

The control unit 510 may include a grouping controller 610 and an environment monitor 620. The grouping controller 610 investigates the performance of UEs 410 (e.g. monitors QoS that the UEs 410 experience) and find an optimal time slot configuration and UE allocation based on QoS requirements of the UEs 410 or access nodes 420.

Fig. 6 shows an example interaction between a grouping controller 610 and an environment monitor 620. The grouping controller 610 interacts with the environment monitor 620 to find an optimal time slot configuration and device allocation scheme. The environment monitor 620 monitors the channel environment and sends feedback to the grouping controller 610.

In Fig. 6, the transition function T describes the environment changes depending on the executed action . The transition function may be unknown initially and

may be learned through reinforcement. After executing the action a_t, the environment responses with a state change, from to . For example, z_t represents the value of events

in the environment or the collision occurrence, i.e. z_t represents the parameter to be observed. The interference from other systems (e.g. access points outsides of control) is modeled through the disturbance variable . The disturbance variable x_t may influence the

environment transition function and thus the state change. The reward function is defined with Jl. The reward is given through For example, as disclosed above, the

reward may be evaluated based on the change of events in response to an action. Determining the environment state s_t is performed through Thus, the environment state

z_t represents an outer state space description, where the grouping controller 610 uses an inner state space representation through

The policy function π selects an action a_t based on the rewards and may be defined as follows:

Fig. 7 shows an example signaling diagram of a process of allocating a UE 410 to a time slot, updating the time slot configuration, and deallocating a UE 410. Fig. 7 shows three phases, i.e., an allocation/registration phase, an evaluation phase, and a deregistration phase. It should be noted that these three phases do not have to be performed in the order as shown in Fig. 7, and one or more of these phases may be performed separately and independently, may be performed in a different order, or may be omitted. For example, an allocation phase for a particular UE may be performed during or after the evaluation phase. In the allocation/registration phase, a UE 410 may send an allocation request to the control unit 510 (e.g. to an access node covering the area that the UE 410 is located) (710). The control unit 510 responses to the UE 410 with an allocation response (714). The allocation response may confirm the allocation request or may reject it due to a certain reason (e.g. unattainability). If the UE 410 is rejected, the UE 410 may request again after a certain waiting time. In case of successful registration, the UE 410 gets an allocation to a specific time slot and may access a channel using CSMA/CA within the allocated time slot.

In a certain time slot configuration, there may be different possibilities to assign the UEs to the time slots. The allocation of the UEs to the time slots may change from time to time. The control unit 510 may evaluate the time slot configuration (e.g. periodically or upon a certain trigger), for example based on how the UEs within a time slot influence the performance of each other. For example, for the evaluation, the control unit 510 (i.e. the grouping controller 610 in the control unit 510) may request UEs 410 to report occurrences of events at the UE 410 according the UE's QoS requirements (716). An event is caused when a required criterion is not met at the UE 410 as explained above. The grouping controller 610 receives the events reports from the UEs 410 (718). The grouping controller 610 may find an optimal time slot allocation based on the events reported by the UEs, and may send an update allocation request to the UEs 410 (720). The UEs 410 may send an update confirmation message to the control unit 510 (722). The grouping controller 610 may update the already assigned time slots to evaluate a different allocation scheme. The evaluation phase may take a couple of iterations to find the best allocation.

When a UE 410 no longer requires a connection with the network, the UE 410 may send a deallocation request to the control unit 510 (724). The control unit 410 may then respond with a deallocation response (726).

Another example is a computer program having a program code for performing at least one of the methods described herein, wherein the computer program is executed on a computer, a processor, a programmable hardware component, or the like. Another example is a machine- readable storage including machine readable instructions, when executed, to implement a method or realize an apparatus as described herein. A further example is a machine-readable medium including code, when executed, to cause a machine to perform any of the methods described herein.

The computer program may include a program code for selecting a time slot configuration, wherein a channel is divided into a plurality of time slots in time domain in accordance with the selected time slot configuration; grouping wireless communication devices into a plurality of groups based on QoS requirements of the wireless communication devices; allocating a group of wireless communication devices to a time slot, wherein the group of wireless communication devices access the channel using a CSMA/CA mechanism; monitoring QoS at the wireless communication devices; and selecting a new time slot configuration based on the monitored QoS.

The examples as described herein may be summarized as follows:

Example 1 is a method for controlling a channel access of a plurality of wireless communication devices. The method comprises selecting a resource slot configuration, wherein a channel is divided into a plurality of resource slots in accordance with the selected resource slot configuration, grouping wireless communication devices into a plurality of groups based on QoS requirements of the wireless communication devices, allocating a group of wireless communication devices to a resource slot, wherein the group of wireless communication devices access the channel using a channel access mechanism, monitoring QoS that the wireless communication devices experience, and selecting a new resource slot configuration based on the monitored QoS.

Example 2 is the method of example 1, wherein the new resource slot configuration is selected among a plurality of potential resource slot configurations.

Example 3 is the method of example 1, wherein the monitored QoS is accumulated over time wherein a learning method is applied to accumulate the monitored QoS.

Example 4 is the method of example 3, wherein a look-up table resulting from the learning method is used to evaluate the plurality of potential resource slot configurations.

Example 5 is the method as in any one of examples 1-4, wherein the resource slot configuration is selected by an AP of a wireless local area network, and the wireless communication devices are user equipments associated with the AP.

Example 6 is the method of example 5, wherein a user equipment operates as the AP.

Example 7 is the method as in any one of examples 1-4, wherein wireless communication devices with a specific QoS requirement below a pre-determined threshold and wireless communication devices with the specific QoS requirement equal to or above the predetermined threshold are grouped separately.

Example 8 is the method as in any one of examples 1-4, wherein wireless communication devices with a specific QoS requirement are grouped separately and allocated in a separate resource slot, wherein the specific QoS requirement is a collision requirement or a delay requirement.

Example 9 is the method as in any one of examples 1-4, wherein the resource slot configuration is selected by a network controller and the wireless communication devices are APs of wireless local area networks.

Example 10 is the method of example 9, wherein a UE operates as an AP. Example 11 is the method of example 9, wherein the APs are allocated to resource slots based on at least one of a geographic distance from neighboring APs and a size of coverage area of the APs.

Example 12 is the method as in any one of examples 1-4, wherein each of the wireless communication devices belongs to a specific tier depending on a priority to access the channel in a spectrum sharing mechanism, and a group of wireless communication devices that belong to a specific tier is allocated to a specific resource slot to control access duration of the group of wireless communication devices. Example 13 is the method as in any one of examples 1-4, wherein the resource slots to which the channel is divided into are defined as time slots, frequency slots, antenna polarization slots, MEVIO slots, space slots, or any combination thereof.

Example 14 is the method as in any one of examples 1-4, wherein the channel access mechanism is a distributed channel access mechanism.

Example 15 is the method of example 14, wherein the channel access mechanism is CSMA/CA. Example 16 is the method as in any one of examples 1-4, wherein the QoS requirements include at least one of collision requirements, delay requirements, power efficiency requirements, or subscription type requirements. Example 17 is a network device for controlling a channel access of a plurality of wireless communication devices. The network device comprises an environment monitor configured to monitor QoS that wireless communication devices experience, and a grouping controller configured to select a resource slot configuration, wherein a channel is divided into a plurality of resource slots in accordance with the selected resource slot configuration, group wireless communication devices into a plurality of groups based on QoS requirements of the wireless communication devices, allocate a group of wireless communication devices to a resource slot, wherein the group of wireless communication devices access the channel using a channel access mechanism, and select a new resource slot configuration based on the monitored QoS at the wireless communication devices.

Example 18 is the network device of example 17, wherein the new resource slot configuration is selected among a plurality of potential resource slot configurations.

Example 19 is the network device of example 17, wherein the monitored QoS is accumulated over time wherein a learning method is applied to accumulate the monitored QoS.

Example 20 is the network device of example 19, wherein a look-up table resulting from the learning method is used to evaluate the plurality of potential resource slot configurations.

Example 21 is the network device as in any one of examples 17-20, wherein the network device is an AP of a wireless local area network and the wireless communication devices are user equipment associated with the AP, and the resource slot configuration is selected by the AP.

Example 22 is the network device of example 21, wherein a user equipment operates as the AP. Example 23 is the network device as in any one of examples 17-20, wherein wireless communication devices with a specific QoS requirement below a pre-determined threshold and wireless communication devices with the specific QoS requirement equal to or above the pre-determined threshold are grouped separately.

Example 24 is the network device as in any one of examples 17-20, wherein wireless communication devices with a specific QoS requirement are grouped separately and allocated in a separate resource slot, wherein the specific QoS requirement is a collision requirement or a delay requirement.

Example 25 is the network device as in any one of examples 17-20, wherein the network device is a controlling entity in a network and the wireless communication devices are APs of wireless local area networks controlled by the controlling entity, and the resource slot configuration is selected by the controlling entity.

Example 26 is the network device of example 25, wherein a user equipment operates as an AP.

Example 27 is the network device of example 25, wherein the APs are allocated to resource slots based on at least one of a geographic distance from neighboring APs and a size of coverage area of the APs.

Example 28 is the network device as in any one of examples 17-20, wherein each of the wireless communication devices belongs to a specific tier depending on a priority to access the channel in a spectrum sharing mechanism, and the grouping controller allocates a group of wireless communication devices that belong to a specific tier to a specific resource slot to control access duration of the group of wireless communication devices.

Example 29 is the network device as in any one of examples 17-20, wherein the resource slots to which the channel is divided into are defined as time slots, frequency slots, antenna polarization slots, MEVIO slots, space slots, or any combination thereof.

Example 30 is the network device as in any one of examples 17-20, wherein the channel access mechanism is a distributed channel access mechanism. Example 31 is the network device of example 30, wherein the channel access mechanism is CSMA/CA. Example 32 is the network device as in any one of examples 17-20, wherein the QoS requirements include at least one of collision requirements, delay requirements, power efficiency requirements, or subscription type requirements.

Example 33 is an apparatus for controlling a channel access of a plurality of wireless communication devices. The apparatus comprises means for selecting a resource slot configuration, wherein a channel is divided into a plurality of resource slots in accordance with the selected resource slot configuration, means for grouping wireless communication devices into a plurality of groups based on QoS requirements of the wireless communication devices, means for allocating a group of wireless communication devices to a resource slot, wherein the group of wireless communication devices access the channel using a channel access mechanism, means for monitoring QoS that the wireless communication devices experience, and means for selecting a new resource slot configuration based on the monitored QoS. Example 34 is the apparatus of example 33, wherein the apparatus is an AP.

Example 35 is the apparatus of example 33, wherein the apparatus is a UE.

Example 36 is the apparatus as in any one of examples 33-35, wherein the resource slots to which the channel is divided into are defined as time slots, frequency slots, antenna polarization slots, MTMO slots, space slots, or any combination thereof.

Example 37 is the apparatus as in any one of examples 33-35, wherein the channel access mechanism is a distributed channel access mechanism.

Example 38 is the apparatus of example 37, wherein the channel access mechanism is CSMA/CA. Example 39 is the apparatus of example 38, wherein the wireless communication devices compete for accessing the channel using CSMA/CA.

Example 40 is the apparatus as in any one of examples 33-35, wherein the QoS requirements include at least one of collision requirements, delay requirements, power efficiency requirements, or subscription type requirements.

Example 41 is a computer program having a program code for performing the method of at least one of examples 1 to 16, when the computer program is executed on a computer, a processor, or a programmable hardware component.

Example 42 is a machine-readable storage including machine readable instructions, when executed, to implement a method of at least one of examples 1-16.

Example 43 is a machine-readable medium including code, when executed, to cause a machine to perform the method of any one of examples 1 to 16.

Example 44 is a network controller configured to perform a method in any one of examples 1-16.

Example 45 is a machine-readable medium including code, when executed, to cause a machine to perform a method comprising: selecting a resource slot configuration, wherein a channel is divided into a plurality of resource slots in accordance with the selected resource slot configuration, grouping wireless communication devices into a plurality of groups based on QoS requirements of the wireless communication devices, allocating a group of wireless communication devices to a resource slot, wherein the group of wireless communication devices access the channel using a channel access mechanism, monitoring QoS that the wireless communication devices experience, and selecting a new resource slot configuration based on the monitored QoS.

Example 46 is an integrated circuit (IC) for controlling a channel access of a plurality of wireless communication devices. The IC comprises means for selecting a resource slot configuration, wherein a channel is divided into a plurality of resource slots in accordance with the selected resource slot configuration, means for grouping wireless communication devices into a plurality of groups based on QoS requirements of the wireless communication devices, means for allocating a group of wireless communication devices to a resource slot, wherein the group of wireless communication devices access the channel using a channel access mechanism, means for monitoring QoS that the wireless communication devices experience, and means for selecting a new resource slot configuration based on the monitored QoS.

The aspects and features mentioned and described together with one or more of the previously detailed examples and figures, may as well be combined with one or more of the other examples in order to replace a like feature of the other example or in order to additionally introduce the feature to the other example.

Examples may further be or relate to a computer program having a program code for performing one or more of the above methods, when the computer program is executed on a computer or processor. Steps, operations or processes of various above-described methods may be performed by programmed computers or processors. Examples may also cover program storage devices such as digital data storage media, which are machine, processor or computer readable and encode machine-executable, processor-executable or computer- executable programs of instructions. The instructions perform or cause performing some or all of the acts of the above-described methods. The program storage devices may comprise or be, for instance, digital memories, magnetic storage media such as magnetic disks and magnetic tapes, hard drives, or optically readable digital data storage media. Further examples may also cover computers, processors or control units programmed to perform the acts of the above-described methods or (field) programmable logic arrays ((F)PLAs) or (field) programmable gate arrays ((F)PGAs), programmed to perform the acts of the above-described methods.

The description and drawings merely illustrate the principles of the disclosure. Furthermore, all examples recited herein are principally intended expressly to be only for pedagogical purposes to aid the reader in understanding the principles of the disclosure and the concepts contributed by the inventor(s) to furthering the art. All statements herein reciting principles, aspects, and examples of the disclosure, as well as specific examples thereof, are intended to encompass equivalents thereof. A functional block denoted as "means for ... " performing a certain function may refer to a circuit that is configured to perform a certain function. Hence, a "means for s.th." may be implemented as a "means configured to or suited for s.th.", such as a device or a circuit configured to or suited for the respective task.

Functions of various elements shown in the figures, including any functional blocks labeled as "means", "means for providing a sensor signal", "means for generating a transmit signal.", etc., may be implemented in the form of dedicated hardware, such as "a signal provider", "a signal processing unit", "a processor", "a controller", etc. as well as hardware capable of executing software in association with appropriate software. When provided by a processor, the functions may be provided by a single dedicated processor, by a single shared processor, or by a plurality of individual processors, some of which or all of which may be shared. However, the term "processor" or "controller" is by far not limited to hardware exclusively capable of executing software, but may include digital signal processor (DSP) hardware, network processor, application specific integrated circuit (ASIC), field programmable gate array (FPGA), read only memory (ROM) for storing software, random access memory (RAM), and non-volatile storage. Other hardware, conventional and/or custom, may also be included. A block diagram may, for instance, illustrate a high-level circuit diagram implementing the principles of the disclosure. Similarly, a flow chart, a flow diagram, a state transition diagram, a pseudo code, and the like may represent various processes, operations or steps, which may, for instance, be substantially represented in computer readable medium and so executed by a computer or processor, whether or not such computer or processor is explicitly shown. Methods disclosed in the specification or in the claims may be implemented by a device having means for performing each of the respective acts of these methods.

It is to be understood that the disclosure of multiple acts, processes, operations, steps or functions disclosed in the specification or claims may not be construed as to be within the specific order, unless explicitly or implicitly stated otherwise, for instance for technical reasons. Therefore, the disclosure of multiple acts or functions will not limit these to a particular order unless such acts or functions are not interchangeable for technical reasons. Furthermore, in some examples a single act, function, process, operation or step may include or may be broken into multiple sub-acts, -functions, -processes, -operations or -steps, respectively. Such sub acts may be included and part of the disclosure of this single act unless explicitly excluded.

Furthermore, the following claims are hereby incorporated into the detailed description, where each claim may stand on its own as a separate example. While each claim may stand on its own as a separate example, it is to be noted that - although a dependent claim may refer in the claims to a specific combination with one or more other claims - other examples may also include a combination of the dependent claim with the subject matter of each other dependent or independent claim. Such combinations are explicitly proposed herein unless it is stated that a specific combination is not intended. Furthermore, it is intended to include also features of a claim to any other independent claim even if this claim is not directly made dependent to the independent claim.

Claims

What is claimed is: 1. A method for controlling a channel access of a plurality of wireless communication devices, the method comprising:

selecting a resource slot configuration, wherein a channel is divided into a plurality of resource slots in accordance with the selected resource slot configuration;

grouping wireless communication devices into a plurality of groups based on quality of service (QoS) requirements of the wireless communication devices;

allocating a group of wireless communication devices to a resource slot, wherein the group of wireless communication devices access the channel using a channel access mechanism; monitoring QoS that the wireless communication devices experience; and

selecting a new resource slot configuration based on the monitored QoS.

2. The method of claim 1, wherein the new resource slot configuration is selected among a plurality of potential resource slot configurations.

3. The method of claim 1, wherein the monitored QoS is accumulated over time wherein a learning method is applied to accumulate the monitored QoS.

4. The method as in any one of claims 1-3, wherein the resource slot configuration is selected by an access point (AP) of a wireless local area network, and the wireless communication devices are user equipments associated with the AP.

5. The method of claim 4, wherein a user equipment operates as the AP.

6. The method as in any one of claims 1-3, wherein the resource slot configuration is selected by a network controller and the wireless communication devices are access points (APs) of wireless local area networks.

7. The method of claim 6, wherein a user equipment (UE) operates as an AP.

8. The method as in any one of claims 1-3, wherein each of the wireless communication devices belongs to a specific tier depending on a priority to access the channel in a spectrum sharing mechanism, and a group of wireless communication devices that belong to a specific tier is allocated to a specific resource slot to control access duration of the group of wireless communication devices.

9. The method as in any one of claims 1-3, wherein the resource slots to which the channel is divided into are defined as time slots, frequency slots, antenna polarization slots, multiple-input multiple-output (MIMO) slots, space slots, or any combination thereof.

10. The method as in any one of claims 1-3, wherein the channel access mechanism is carrier sense multiple access/collision avoidance (CSMA/CA).

11. The method as in any one of claims 1-3, wherein the QoS requirements include at least one of collision requirements, delay requirements, power efficiency requirements, or subscription type requirements.

12. A network device for controlling a channel access of a plurality of wireless communication devices, the network device comprising:

an environment monitor configured to monitor quality of service (QoS) that wireless communication devices experience; and

a grouping controller configured to select a resource slot configuration, wherein a channel is divided into a plurality of resource slots in accordance with the selected resource slot configuration, group wireless communication devices into a plurality of groups based on QoS requirements of the wireless communication devices, allocate a group of wireless communication devices to a resource slot, wherein the group of wireless communication devices access the channel using a channel access mechanism, and select a new resource slot configuration based on the monitored QoS at the wireless communication devices.

13. The network device of claim 12, wherein the new resource slot configuration is selected among a plurality of potential resource slot configurations.

14. The network device of claim 12, wherein the monitored QoS is accumulated overtime wherein a learning method is applied to accumulate the monitored QoS.

15. The network device as in any one of claims 12-14, wherein the network device is an access point (AP) of a wireless local area network and the wireless communication devices are user equipment associated with the AP, and the resource slot configuration is selected by the AP.

16. The network device of claim 15, wherein a user equipment operates as the AP.

17. The network device as in any one of claims 12-14, wherein the network device is a controlling entity in a network and the wireless communication devices are access points (APs) of wireless local area networks controlled by the controlling entity, and the resource slot configuration is selected by the controlling entity.

18. The network device of claim 17, wherein a user equipment operates as an AP.

19. The network device as in any one of claims 12-14, wherein each of the wireless communication devices belongs to a specific tier depending on a priority to access the channel in a spectrum sharing mechanism, and the grouping controller allocates a group of wireless communication devices that belong to a specific tier to a specific resource slot to control access duration of the group of wireless communication devices.

20. The network device as in any one of claims 12-14, wherein the resource slots to which the channel is divided into are defined as time slots, frequency slots, antenna polarization slots, multiple-input multiple-output (MIMO) slots, space slots, or any combination thereof.

21. The network device as in any one of claims 12-14, wherein the channel access mechanism is carrier sense multiple access/collision avoidance (CSMA/CA).

22. The network device as in any one of claims 12-14, wherein the QoS requirements include at least one of collision requirements, delay requirements, power efficiency requirements, or subscription type requirements.

23. An apparatus for controlling a channel access of a plurality of wireless communication devices, the apparatus comprising: means for selecting a resource slot configuration, wherein a channel is divided into a plurality of resource slots in accordance with the selected resource slot configuration;

means for grouping wireless communication devices into a plurality of groups based on quality of service (QoS) requirements of the wireless communication devices;

means for allocating a group of wireless communication devices to a resource slot, wherein the group of wireless communication devices access the channel using a channel access mechanism;

means for monitoring QoS that the wireless communication devices experience; and means for selecting a new resource slot configuration based on the monitored QoS.

24. The apparatus of claim 23, wherein the resource slots to which the channel is divided into are defined as time slots, frequency slots, antenna polarization slots, multiple-input multiple-output (MEVIO) slots, space slots, or any combination thereof.

25. The apparatus as in any one of claims 23-24, wherein the QoS requirements include at least one of collision requirements, delay requirements, power efficiency requirements, or subscription type requirements.