Slow preamble puncturing

Abstract

A wideband (WB) wireless device is provided. The WB wireless device is configured to operate communication according to an LBT procedure through a plurality of resource units (RUs) forming a main channel and one or more auxiliary channels to transmit a PHY protocol data unit (PPDU), and the PPDU bandwidth is equal to the frequency covered by the RUs for the LBT procedure. The WB device is further configured to modify the PPDU bandwidth by removing one or more RUs within the first auxiliary channel when narrowband (NB) interference is present in the first auxiliary channel during the first LBT procedure, perform a subsequent second LBT procedure on the modified PPDU bandwidth, and transmit the PPDU with the modified PPDU bandwidth after the second LBT procedure.

Description

Technology Field

[0001] The present disclosure relates to wireless communication, and in particular to a configuration for preamble puncturing. Background Technology

[0002] Wi-Fi, also known as a Wireless Local Area Network (WLAN), is a technology currently operating primarily in the 2.4 GHz or 5 GHz bands. To ensure compatibility and interoperability between different WLAN entities, such as between an access point and a mobile terminal, standards exist that regulate the physical (PHY) layer, the Media Access Control (MAC) layer, and other aspects of the access point or wireless terminal; both the access point and the mobile terminal may be referred to as a Station (STA) in this specification. Wi-Fi generally operates in unlicensed bands, and therefore, communication over Wi-Fi may be affected by interference sources from any number of known and unknown devices. Wi-Fi is generally used as a wireless extension of fixed broadband access in hotspots, such as airports, train stations, and restaurants, as well as in home environments.

[0003] Wireless coexistence

[0004] For example, when operating in unlicensed bands such as 2.4 GHz ISM, 5 GHz band, or 6 GHz band, some means of spectrum sharing mechanism is typically required unless transmission is restricted to using very low power. Two exemplary spectrum sharing mechanisms are listen-before-talk (LBT), also referred to as carrier sense multiple access with collision avoidance (CSMA / CA), and frequency hopping (FH).

[0005] The operating procedure of LBT is as the name suggests. Before a transmission can be initiated, the transmitter listens to the channel to determine whether the channel is idle or if there is another transmission already in progress. If the channel is identified as idle, a transmission can be initiated; however, if the channel is identified as busy, the transmitter must abandon the transmission and essentially continue to monitor the channel until it becomes idle. LBT is used by different versions of IEEE 802.11, commonly referred to as Wi-Fi, operating in the 2.4 GHz ISM (Industrial, Scientific and Medical) band as well as, for example, the 5 GHz and 6 GHz bands. LBT is also adopted by standards developed by 3GPP operating in the 5 GHz band, such as NR-U (New Radio-Unlicensed). When FH is used, spectrum sharing is based on using only a specific portion of the band for a relatively small fraction of the total time to leave space for other transmissions. FH is an approach used by Bluetooth (BT).

[0006] While it is not obvious whether to adopt LBT or FH, LBT is generally the preferred approach if the channel bandwidth used is relatively large, for example, 20 MHz or more, and the required channel usage is highly dynamic with significant variability. On the other hand, FH is highly suitable for narrowband systems where the occupied bandwidth is much smaller (around 1 or 2 MHz) and predictable and deterministic channel usage is required.

[0007] While both LBT and FH can be considered effective spectrum sharing mechanisms, both typically work well only when all devices use the same spectrum sharing mechanism. That is, if all devices apply LBT or use FH, the devices tend to work well. However, if some devices use LBT while others use FH, the devices may not work properly. For example, a broadband system using LBT may detect a narrowband transmission and delay it, even though the transmission would have been successful without significant damage to the narrowband system. Conversely, because the average sense power within the broadband channel is relatively low, the broadband system may fail to detect the narrowband system and subsequently initiate a transmission that could potentially cause harmful interference to the narrowband system.

[0008] The above situation exists in the 2.4 GHz ISM band, where Wi-Fi uses LBT while BT uses FH. To allow for good coexistence between the two standards, BT has developed support for Adaptive FH (AFH), which means that a BT device detects whether Wi-Fi transmission is present on some Wi-Fi channels and then adapts the hopping pattern used for FH so that frequencies matching the Wi-Fi channels are not used (in this specification, these channels are referred to as blacklisted channels). In Bluetooth LE (BLE), only three channels are used for initial link establishment, and additional specific measures are taken to limit interference to Wi-Fi by selecting these three channels so that they do not overlap with, for example, the three most used Wi-Fi channels in the 2.4 GHz ISM band, namely channels 1, 6, and 11.

[0009] Preamble puncturing in IEEE 802.11

[0010] A feature introduced in the IEEE 802.11ax ('High Efficiency', HE) revision is 'preamble puncturing'. Preamble puncturing allows an HE station (STA) to transmit or receive a Physical Protocol Data Unit (PPDU) over the channel even when that portion of the channel bandwidth is not occupied by the PPDU being transmitted or received. In other words, the corresponding portion of the bandwidth of the entire PPDU, including the preamble as well as the data field, is left empty. It is important to note that this mechanism applies only to preambles where a 20 MHz 'hole' is transmitted at zero energy, which leads to a punctured preamble. In the remaining portion, HE's ability to allocate different parts of the frequency band to users by allocating 'Resource Units (RUs)' is applied, so the 20 MHz hole is not allocated to any user. Consequently, no energy is transmitted in these holes even during the data portion of the PPDU. Therefore, by combining 'preamble puncturing' with a matching RU allocation, the entire PPDU can be considered punctured.

[0011] A typical use of ‘preamble puncturing,’ referred to as ‘puncturing’ below, is when a specific part of the operating bandwidth of the BSS is evaluated as unavailable based on applicable rules and regulations in the presence of an existing system (incumbent) with higher priority (e.g., radar signal), or is evaluated as ‘busy’ due to the presence of an OBSS signal, interference, or noise.

[0012] Since 'puncturing' of the data portion is based on allocating RUs to the receiver(s) of the PPDU, puncturing in HE is limited to valid RU allocations defined by HE's Orthogonal Frequency Division Multiple Access (OFDMA)-based multi-user transmission. The IEEE 802.11be Extremely High Throughput (EHT) amendment extends the flexibility of RU allocation to support OFDM transmission for a single user as well as much more bandwidth division involving OFDMA.

[0013] According to the HE and EHT amendments, the 'preamble puncturing' granularity for HE as well as EHT PPDU is 20 MHz. For example, a 20 MHz portion can be punctured in an 80 MHz channel, or a 40 MHz portion can be punctured in a 160 MHz channel. Therefore, in EHT, aggregate bandwidths such as 60 MHz or 120 MHz are possible.

[0014] Narrowband (NB) interference to broadband (WB) systems can be problematic in several different ways. First, NB transmission can prevent WB devices from accessing the communication medium, which can be considered wasteful because, as illustrated in the diagram in Fig. 1, for example, using only 1 MHz of spectrum can render a 160 MHz channel unusable, leaving many resources unused. Second, due to power being highly concentrated in a very narrow bandwidth, it can be very difficult for WB systems to handle interference from narrowband signals.

[0015] Therefore, existing systems may face difficulties due to various coexistence issues.

[0016] Aspects of the invention are provided by the appended independent claims, and embodiments of the invention are provided by the appended dependent claims.

[0017] Some embodiments advantageously provide a method, system, and apparatus for preamble puncturing in a wireless communication system.

[0018] In one or more embodiments, puncturing is proposed when a broadband transmitter receives narrowband interference. The implementation takes into account that it may be very difficult to achieve ideal puncturing due to the limited processing time between detecting the interference and the transmission occurring. Brief explanation of the drawing

[0019] A more complete understanding of the present embodiment, and the advantages and features associated with the present embodiment, will be more easily understood by referring to the following detailed description when considered together with the attached drawings. Figure 1 is a diagram of an example showing how NBFH transmission can block WB transmission, leading to large spectral inefficiency. FIG. 2 is a schematic diagram of an exemplary network architecture illustrating a communication system according to the principles of the present disclosure. FIG. 3 is a block diagram of an AP communicating with a non-AP STA (Non-AP STA) through at least a partial wireless connection according to some embodiment of the present disclosure. FIG. 4 is a flowchart of an exemplary process in a non-AP STA according to some embodiments of the present disclosure. FIG. 5 is an exemplary schematic diagram showing how a subsequent punctured PPDU pattern is selected based on channel detection according to some embodiments of the present disclosure. FIG. 6 is another exemplary schematic diagram showing how a subsequent punctured PPDU pattern is selected based on channel detection according to some embodiments of the present disclosure. FIG. 7 is a diagram of a performance plot showing the FTP download delay of a 10 MB file having different coexistence mechanisms in a scenario in which 1 to 6 BT devices act as interfering bodies according to some embodiments of the present disclosure. FIG. 8 is a diagram of a performance plot showing the gaming latency of a cloud gaming user with different coexistence mechanisms in a scenario where 1 to 6 BT devices act as interfering bodies according to some embodiments described in this specification. Specific details for implementing the invention

[0020] There is a need to improve the coexistence between WB systems and NB systems, and specifically, for example, it may be beneficial for WB systems to reduce their operating bandwidth by using puncturing to attempt to avoid NB devices.

[0021] However, performing this can be a very difficult task because puncturing cannot be fully dynamic in most implementations. This is due to the very limited time between detecting narrowband interference and performing transmission, which may not leave enough time to reassemble data units for transmission.

[0022] Therefore, there is a need for an efficient and feasible puncturing algorithm to avoid NB interference.

[0023] One or more embodiments described in this specification solve one or more problems of existing systems by providing, for example, a puncturing algorithm to avoid NB interference.

[0024] Before describing exemplary embodiments in detail, it should be noted that the embodiments are primarily composed of a combination of device components and processing steps related to preamble puncturing based, for example, on PHY protocol data unit (PPDU) resizing. Accordingly, components are indicated in the drawings by conventional symbols where appropriate, and the drawings illustrate only specific details suitable for understanding the embodiments so as not to obscure the disclosure with details that will be readily apparent to those skilled in the art who benefit from the description in this specification. Similar numbers refer to similar elements throughout the description.

[0025] As used herein, relational terms such as “first” and “second,” “top” and “bottom,” etc., may be used solely to distinguish one entity or element from another, without necessarily requiring or implying any physical or logical relationship or order between these entities or elements. The technical terms used herein are for the purpose of describing specific embodiments only and are not intended to limit the concepts described herein. As used herein, unless the context clearly indicates otherwise, the singular form is intended to also include the plural form. Additionally, it will be understood that when the terms “comprising,” “comprising,” “comprising,” and / or “comprising” are used herein, they specify the presence of the mentioned feature, integer, step, action, element, and / or component, but do not exclude the presence or addition of one or more other features, integers, steps, actions, elements, components, and / or groups thereof.

[0026] In the embodiments described herein, connection terms, such as "in communication with," may be used to indicate electrical or data communication, which may be achieved, for example, by physical contact, induction, electromagnetic radiation, radio signaling, infrared signaling, or optical signaling. Those skilled in the art will recognize that a number of components may be interoperable and that modifications and variations are possible to achieve electrical and data communication.

[0027] In some embodiments described herein, terms such as “coupled,” “connected,” etc. may be used herein to indicate a connection, although not necessarily a direct one, and may include wired and / or wireless connections.

[0028] In some embodiments, the terms "access point" or "AP" are used interchangeably and may include or be network nodes. The AP may include any of the following: a base station (BS), a radio base station, a base station transceiver (BTS), a base station controller (BSC), a radio network controller (RNC), a g Node B (gNB), an evolved Node B (eNB or eNodeB), a Node B, a multi-standard radio (MSR) radio node such as an MSR BS, a multi-cell / multicast coordination entity (MCE), a relay node, an integrated access and backhaul (IAB), a donor node controlling relay, a radio access point (AP), a transmission point, a transmission node, a remote radio unit (RRU) remote radio head (RRH), a core network node (e.g., a mobile management entity (MME), a self-configuring network (SON) node, a coordination node, a positioning node, an MDT node, etc.), an external node (e.g., a third-party node, a node outside the current network), nodes within a distributed antenna system (DAS), a spectrum access system (SAS) node, an element management system (EMS), etc. The AP may also include test equipment. APs may include wireless routers, wireless transceivers, Wi-Fi access points, wireless local area network (WLAN) access points, network controllers, etc.

[0029] In some embodiments, the non-limiting term “device” is used to describe a wireless device (WD) and / or user equipment (UE) that may be used to implement some embodiments of the present disclosure. In some embodiments, the device may be an access point (AP) station (STA) and / or may include it. In some embodiments, the device may be a non-access point station (non-AP STA) and / or may include it. In some embodiments, the device may be any type of device capable of communicating with a network node, such as an AP, via a wireless signal. The device may be any wireless communication device, target device, portable device, device-to-device (D2D) device, machine-type device or machine-to-machine (M2M) capable device, low-cost and / or low-complexity device, sensor equipped with a device, computer, tablet, mobile terminal, smartphone, laptop embedded device (LEE), laptop embedded device (LME), USB dongle, customer premises equipment (CPE), Internet of Things (IoT) device, Narrowband IoT (NB-IoT) device, or reduced capability (RedCap) device, etc.

[0030] A device may be considered a network node and may include physical components such as a processor, allocated processing elements or other computing hardware, computer memory, communication interfaces, and other supporting computing hardware. A network node may use dedicated physical components, or the node may be assigned to use physical components of other devices, such as computing devices or data center resources; in this case, the network node is said to be virtualized. A network node may be associated with multiple physical components that may be located in a single location or distributed across multiple locations.

[0031] Although the description in this specification may be made in the context of either downlink (DL) or uplink (UL) communication, it should be understood that the disclosed basic principles may also be applicable to the other of DL and UL communication. In some embodiments of this disclosure, the principles may be considered applicable to transmitters and receivers. For DL ​​communication, the AP station may be a transmitter and the receiver is a non-AP station. For UL communication, the transmitter may be a non-AP station and the receiver is an AP station.

[0032] It should also be noted that some embodiments of this disclosure may be supported by the Institute of Electrical Engineers (IEEE) 802.11 standard. IEEE 802.11 represents a set of wireless local area network (WLAN) air interface standards developed by the IEEE 802.11 Committee for short-range communication (e.g., tens of meters to hundreds of meters). Some embodiments may also be supported by standard documents disclosed in the Third Generation Partnership Project (3GPP) technical specifications. That is, some embodiments of the description may be supported by the above documents. Furthermore, all terms disclosed in this document may be explained by the above standard documents.

[0033] It should be noted that while technical terms from a specific wireless system, such as IEEE 802.11, 3GPP, LTE (Long Term Evolution), 5th Generation (5G) and / or NR (New Radio), may be used in this disclosure, this should not be construed as limiting the scope of this disclosure to the aforementioned systems alone. Other wireless systems, including, without limitation, WCDMA (Wide Band Code Division Multiple Access), WiMAX (Worldwide Interoperability for Microwave Access), UMB (Ultra Mobile Broadband), and GSM (Global System for Mobile Communications), may also benefit from utilizing the ideas covered within this disclosure.

[0034] It is further noted that functions described in this specification as being performed by one or more of STAs, APs, non-AP STAs, wireless devices, network nodes, etc. may be distributed across multiple STAs, APs, non-AP STAs, wireless devices, network nodes, etc. In other words, the functions of the devices described in this specification are not limited to being performed by a single physical device, but are considered to be distributed among several physical devices.

[0035] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as generally understood by those skilled in the art to which this disclosure pertains. It will be further understood that terms used herein should be interpreted as having a meaning consistent with the meaning of such terms in the context of this specification and related technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined so in this specification.

[0036] Some embodiments provide configurations for preamble puncturing. Referring again to the drawings where similar elements are referred to by similar reference numerals, FIG. 2 illustrates a schematic diagram of a communication system (10) according to one embodiment configured in accordance with the principles of the present disclosure. The communication system (10) of FIG. 2 is a non-limiting example, and other embodiments of the present disclosure may be implemented by one or more other systems and / or networks. Referring to FIG. 2, the system (10) may include a wireless local area network (WLAN). Devices within the system (10) may communicate over one or more spectrums, such as unlicensed spectrum, which may include frequency bands typically used by Wi-Fi technology, for example. One or more devices may be further configured to communicate over other frequency bands, such as shared licensed frequency bands. The system (10) may include one or more coverage areas (12a, 12b), etc. (collectively referred to as “coverage areas (12”)) that can be defined by corresponding access points (APs) (14a, 14b), etc. (collectively referred to as “APs (14”) in this specification). The APs (14) may or may not be able to connect to another network, such as a core network, via a wired or wireless connection. The system (10) may include a plurality of non-AP devices, such as non-AP STAs (16a, 16b, 16c), etc. (collectively referred to as non-AP STAs (16)). The system (10) may include a plurality of narrowband (NB) non-AP devices (17a, 17b), etc. (collectively referred to as NB non-AP STAs (17)). The NB non-AP STA may operate according to one or more frequency hopping methods, wherein the NB non-AP STA may be configured to perform frequency hopping based partially on the punctured preamble described herein.Each non-AP STA (16) may be located within one or more coverage areas (12) and may be configured to be wirelessly connected to one or more APs (14). For convenience, two APs (14a, 14b) and two non-AP STAs (16a, 16b) are shown, but note that the communication system may include many more non-AP STAs (16) and APs (14). Each AP (14) may be connected to one or more non-AP STAs (16) and may perform tasks such as servicing, configuring, and scheduling.

[0037] It should be understood that the system (10) may include additional nodes / devices not shown in FIG. 2. Furthermore, the system (10) may include far more connections / interfaces than shown in FIG. 2. Accordingly, the elements shown in FIG. 2 are presented for ease of understanding.

[0038] Additionally, the non-AP STA (16) is considered to be able to communicate with more than one AP (14) and / or more than one type of AP (14) and / or configured to communicate separately. Furthermore, the AP (14) may be able to communicate with other APs (14) and / or configured to communicate separately, which may be via wired and / or wireless communication channels.

[0039] The non-AP (16) is configured to include a preamble unit (18), and the preamble unit (18) is configured to perform one or more non-AP (16) functions described herein, for example, in relation to scaling or modifying the PPDU size.

[0040] An exemplary implementation according to one embodiment of the AP (14) and non-AP STA (16) discussed in the previous paragraph will now be described with reference to FIG. 3.

[0041] The AP (14) includes hardware (20) comprising a communication interface (22), a processing circuit (24), a processor (26), and memory (28). The communication interface (22) may be configured to communicate with any node / device within the system (10) according to some embodiments of the present disclosure, such as one or more other APs (14) and / or one or more non-AP STAs (16). In some embodiments, the communication interface (22) may be formed or include, for example, one or more radio frequency (RF) transmitters, one or more RF receivers and / or one or more RF transceivers, or may be considered as a wireless interface. In some embodiments, the communication interface (22) may also include a wired interface.

[0042] The processing circuit (24) may include one or more processors (26) and memory, such as memory (28). In addition to the processor (26) and memory (28), the processing circuit (24) may include an integrated circuit for processing and / or control, such as one or more processors and / or processor cores and / or FPGAs (Field Programmable Gate Arrays) and / or ASICs (Application Specific Integrated Circuitry) adapted to execute instructions. The processor (26) may be configured to access (e.g., write to and / or read from memory (28)) memory (28), which may include any type of volatile and / or non-volatile memory, such as cache and / or buffer memory and / or RAM (Random Access Memory) and / or ROM (Read-Only Memory) and / or optical memory and / or EPROM (Erasable Programmable Read-Only Memory).

[0043] AP (14) may additionally include software (30) stored internally, for example, in memory (28), or in external memory (e.g., a database) accessible by AP (14) via an external connection. Software (30) may be executable by a processing circuit (24). The processing circuit (24) may be configured to control any method and / or process described herein and / or to cause such method and / or process to be performed, for example, by AP (14). Memory (28) is configured to store data, program software code and / or other information described herein. In some embodiments, software (30) may include instructions stored in memory (28) that configure AP (14) to cause the processing circuit (24) to perform a process described herein in relation to AP (14) (e.g., a process described with reference to FIG. 4 and / or any other figure in this specification) when executed by a processor (26) and / or a preamble unit (18), and / or to perform.

[0044] Referring still to FIG. 3, the non-AP STA (16) includes hardware (32), which may include a communication interface (34), a processing circuit (36), a processor (38), and memory (40). The communication interface (34) may be configured to communicate with one or more APs (14) and / or other elements within the system (10), for example, via a wireless connection (35), according to some embodiments of the present disclosure. In some embodiments, the communication interface (34) may be formed or include, for example, one or more radio frequency (RF) transmitters, one or more RF receivers and / or one or more RF transceivers, or may be considered as a wireless interface. In some embodiments, the communication interface (34) may also include a wired interface.

[0045] The processing circuit (36) may include one or more processors (38) and memory, such as memory (40). Furthermore, in addition to traditional processors and memory, the processing circuit (36) may include integrated circuits for processing and / or control, such as one or more processors and / or processor cores and / or FPGAs (Field Programmable Gate Arrays) and / or ASICs (Application Specific Integrated Circuitry) adapted to execute instructions. The processor (38) may be configured to access (e.g., write to and / or read from memory (40)) memory (40), which may include any type of volatile and / or non-volatile memory, such as cache and / or buffer memory and / or RAM (Random Access Memory) and / or ROM (Read-Only Memory) and / or optical memory and / or EPROM (Erasable Programmable Read-Only Memory).

[0046] Accordingly, the non-AP STA (16) may additionally include software (42) stored internally, for example, in memory (40) or stored in external memory (e.g., a database) accessible by the non-AP STA (16) via an external connection. The software (42) may be executable by a processing circuit (36). The processing circuit (36) may be configured to control any method and / or process described herein and / or to cause such method and / or process to be performed, for example, by the non-AP STA (16). The memory (40) is configured to store data, program software code and / or other information described herein. In some embodiments, the software may include instructions stored in a memory (40) that configures the non-AP STA (16) to perform a process described herein (e.g., a process described with reference to FIG. 4 and / or any other figure in the specification) in relation to the non-AP STA (16) when executed by the processor (38).

[0047] In FIG. 3, the connection between the devices, AP (14) and non-AP STA (16), is illustrated without explicit reference to any mediating device or connection. However, it should be understood that mediating devices and / or connections may exist between these devices, although not explicitly illustrated.

[0048] Although FIG. 3 illustrates the preamble unit (18) as being within the processor, it is considered that this element can be implemented such that a part of the element is stored in a corresponding memory within the processing circuit. In other words, the element can be implemented as hardware within the processing circuit or as a combination of hardware and software.

[0049] FIG. 4 is a flowchart of an exemplary process in a first non-AP STA (16) (e.g., a wideband (WB) wireless device (16)) according to one or more embodiments described herein. One or more blocks and / or functions and / or methods performed by the first non-AP STA (16) may be performed by one or more elements of the non-AP STA (16) according to an exemplary process / method, such as a preamble unit (18) in a processing circuit (36), a memory (40), a processor (38), a communication interface (34), etc. The non-AP STA (16) is configured to detect narrowband interference during a listening procedure (block S100) as described herein. The non-AP STA (16) is configured to modify the size of a PHY protocol data unit (PPDU) (block S102) to perform a subsequent listening procedure, wherein the modification is based on the detection of narrowband interference.

[0050] According to one or more embodiments, the PPDU size is modified by statically puncturing a plurality of resource units (RU).

[0051] According to one or more embodiments, the PPDU size may be based at least on channel detection.

[0052] According to one or more embodiments, the listening procedure is a backoff procedure.

[0053] According to one or more embodiments, the PPDU size may be based on at least a previous backoff procedure.

[0054] According to one or more embodiments, the PPDU size is based on the probability that a narrowband interferometer continues to be transmitted on the same channel and the relative difference in the PPDU size after modification.

[0055] According to one or more embodiments, the WB wireless device is an 802.11 WB wireless device.

[0056] According to one or more embodiments, narrowband interference is based on frequency hopping.

[0057] One or more embodiments described herein provide a low-complexity and effective preamble puncturing method for handling the presence of narrowband interference. Due to the limited time between detecting narrowband interference and performing the transmission of the punctured PPDU, puncturing in a completely dynamic manner is a very difficult task, and therefore one or more embodiments described herein determine a puncturing pattern for subsequent PPDU transmission.

[0058] In the following examples, narrowband interference is caused by using a frequency hopping system such as Bluetooth, but the teaching is equally applicable to other wireless communication protocols that can cause narrowband interference.

[0059] Example 1: Static puncturing

[0060] In the first embodiment, the WB wireless device (16) detects narrowband interference and then decides to statically puncture one or more resource units (RUs). This may seem strange at first glance because the NBFH device (e.g., a device causing narrowband interference such as the NB wireless device (17)) is likely to move on different channels depending on the FH method. However, the NBFH device is likely to try and find the best operating channel for the NBFH device's frequency hopping set. For example, Bluetooth uses adaptive frequency hopping to tag a specific channel that Bluetooth considers unsuitable for communication as "unused" for that channel hopping set, and is more likely to start operation on the punctured RU in this way.

[0061] Therefore, this can lead to improved performance for both the WB device (16) and the NBFH device. Furthermore, this method allows the WB device (16) to have control and select the appropriate RU to puncture. For example, if it may be more beneficial to puncture a specific RU than another RU, or if there are multiple interfering NBFH devices, puncturing the smallest available RU may not be sufficient and rather puncturing a subset of multiple RUs is preferred.

[0062] However, in static puncturing, there may be a long convergence time until the NBFH device finds the punctured spectrum and operates on that spectrum (depending on the implementation), and furthermore, there may be no absolute guarantee that the NBFH device will ultimately converge only to that part of the bandwidth (e.g., the punctured part of the bandwidth selected by the WB device (16)).

[0063] Example 2: Slow RU puncturing

[0064] In another embodiment, the WB wireless device (16) punctures in a more dynamic manner than in Example 1 so as not to rely entirely on the operation of the NBFH device, for example, so as not to rely entirely on the NBFH device converging to a punctured portion of the bandwidth. In this case, the puncture is still not entirely dynamic due to the previously mentioned validity limit. Rather, instead of dynamically changing the puncture of the PPDU belonging to the current backoff instance, the puncture size of the PPDU belonging to the subsequent backoff instance is dynamically changed.

[0065] FIG. 5 is an example timing diagram showing how a subsequent punctured PPDU pattern is selected based on channel detection according to one or more embodiments of the present disclosure. For example, a broadband device is operating while sharing a channel with an NBFH device over a 160 MHz channel. Initially, when the WB radio device (16) performs an LBT, the WB radio device (16) performs an LBT with the intention of transmitting a full 160 MHz wide PPDU. According to the method by which IEEE 802.11 bundles 20 MHz channels, initially during the first backoff slot, only the main 20 MHz channel (p20) is observed (indicated by a short solid line in FIG. 5), which is always idle.

[0066] However, at PIFS (25μs) before transmission begins, the device begins observing all 20 MHz segments of the 160 MHz channel (indicated by the long dashed line in FIG. 5). Consequently, the WB radio device (16) detects NB interference, and the backoff fails. According to Example 2, instead of waiting for the NB transmission to be completed, the WB radio device (16) restarts its LBT procedure but now has a PPDU (in this case, 40 MHz) limited to the maximum available channel bandwidth containing the main channel that avoids NB interference. This constraint allows the WB radio device (16) to successfully complete the backoff procedure and transmit the PPDU.

[0067] Referring again to FIG. 5, in the final slot of the backoff procedure, the WB wireless device (16) detects that there is still ongoing NB interference when data transmission begins (indicated by a shorter dashed line) and accordingly remembers this for the next channel access attempt (e.g., storing data indicating such ongoing NB interference). Therefore, at the start of the next channel access attempt, the WB wireless device (16) immediately limits the PPDU bandwidth to 40 MHz and thereby increases the probability of successfully completing the backoff.

[0068] In the timing diagram of Fig. 6, NB interference is interrupted during the backoff procedure. As described above, the broadband device has already prepared a 40 MHz PPDU, which is not changed. However, in the final backoff slot before transmission, the broadband device detects that NB interference has been interrupted (as indicated by the longer dashed line), and therefore prepares a full 160 MHz PPDU in a subsequent attempt.

[0069] By using this method, narrowband interference that remains at the same frequency for a longer period of time can be effectively avoided. Furthermore, by reducing the size of the transmitted PPDU, the possibility of it being blocked by another NBFH device is reduced.

[0070] Furthermore, by maintaining a trace of successful PPDU formats in memory (40), the WB wireless device (16) may decide to use this method in a statistical manner when narrowband interference is not persistent. Thus, depending on how much narrowband interference is present, the operating channel will be reduced by the WB wireless device (16) to allow a good opportunity to access the channel (see FIG. 5).

[0071] In another example, the WB wireless device (16) considers not only the possibility of NB interference being present in the channel, but also the potential benefits of using a wider channel bandwidth. For example, if this means that a much wider channel bandwidth can be adopted, it may be beneficial for the WD wireless device (16) to attempt to wait for the interference to pass. In other cases, it may also be beneficial for the WB wireless device (16) to attempt a wider bandwidth PPDU first and then restart the LBT after detecting NB interference.

[0072] In another example, the WB wireless device (16) may also want to consider what type of traffic is being transmitted. For example, by selecting a reduced PPDU format and applying a puncturing pattern, the probability of successful channel access increases, but the total data that can be transmitted within the PPDU is reduced. Therefore, for latency-sensitive applications (e.g., software applications running on the WB wireless device (16)), it may be more beneficial to select a stricter PPDU format to attempt to guarantee channel access, whereas applications that rely more on high throughput may want to choose to wait for narrowband interference to pass.

[0073] Below, some performance curves of this method are described in a simulation scenario in which three Wi-Fi APs use non-overlapping 160 MHz channels to communicate with three Wi-Fi STAs (e.g., WB wireless devices (16)). The Wi-Fi nodes are interfered with by one to six Bluetooth links transmitting 1280B of data with a periodicity of 20 milliseconds.

[0074] In the example illustrated in the graph of Figure 7, the Wi-Fi STA performs FTP file downloads, and thus the key performance metric measured is the average file download latency. In this case, using ideal full dynamic puncturing shows significant gains compared to the case without puncturing, whereas slow puncturing shows minimal or no gain. For this traffic assumption, raw throughput is important. However, the implementation of slow puncturing within the simulation does not effectively utilize the available spectrum because it punctures only with valid RU sizes. For example, a 160 MHz channel can only be punctured with 80 / 40 / 20 MHz transmissions, and thus many valuable resources are left unused. A more effective implementation that utilizes the mRU introduced in 11be (e.g., 802.11be) or allocates RUs to multiple users can achieve better spectrum efficiency and thus increase gains, even in the case of FTP.

[0075] In contrast, the graph in Fig. 8 shows the results when FTP traffic is replaced by cloud gaming traffic, namely high-speed video downlink (average 30 MB / s) and small but high-frequency control traffic uplink (15 ms inter-frame duration). As a key performance metric, the worst-case round-trip time corresponding to the gaming latency observed by the user (i.e., the sum of the 99th percentiles of uplink and downlink latency) is used. From the results, it can be seen that while ideal fully dynamic puncturing still provides the best performance, there is already a significant benefit in using slow-adapting puncturing compared to the case without puncturing. This result can be explained by the fact that for such latency-sensitive traffic, reducing channel access time is important, while maximum throughput is secondary, especially for small control uplink frames.

[0076] Therefore, one or more embodiments described in this specification are beneficial for latency-threshold applications where a reduction in the time to access a channel in the presence of narrowband interference is important.

[0077] Additional examples

[0078] In the present disclosure, the frequency hopping device is assumed to be a narrowband interference device. However, it should be noted that the teachings described herein may also be applied to handle narrowband interference from technology that stays on the same frequency channel or does not change its operating channel very frequently.

[0079] Furthermore, in some scenarios, the narrowband interferometer may be any technology operating in a narrower band than the broadband device. For example, if there is one or more 20 MHz Wi-Fi APs operating on separate channels within a larger 160 MHz channel, the broadband wireless device (16) may also utilize the present disclosure to find a suitable PPDU format for subsequent channel attempts.

[0080] Therefore, according to one or more embodiments, a broadband transmitter can achieve much better channel access delay and throughput when the medium is shared with a narrowband device compared to a conventional coexistence method.

[0081] Some non-limiting examples

[0082] 1. A method within a broadband wireless device (16) for improving channel access delay or throughput of the broadband wireless device (16) in an environment shared with a narrowband interferometer, wherein the method comprises:

[0083] Step to initiate a backoff procedure to access the wireless medium,

[0084] A step of detecting narrowband interference that forces a wireless device to stop a backoff procedure,

[0085] It includes the step of selecting a PPDU size for a subsequent backoff procedure based on the use of a narrowband interference frequency.

[0086] 2. In the method of Example 1, the wireless device selects the same PPDU format that cleared the previous backoff attempt.

[0087] 3. In the method of Example 2, the decision to select the same PPDU format is based on detecting narrowband interference until transmission occurs.

[0088] 4. In the method of Example 1, the WB wireless device (16) stores one or more previous successful PPDU formats in memory and selects the next PPDU size based on statistics.

[0089] 5. In the method of Example 1, the WB wireless device (16) statically selects a punctured PPDU format.

[0090] 6. In any one of the methods of Examples 1 to 5, the determination of the PPDU size takes into account the probability that the NB interferometer will continue to transmit on the same channel and the relative difference in PPDU size.

[0091] 7. In any one of the methods of Examples 1 to 6, the WB wireless device (16) is an 802.11 STA.

[0092] 8. In the method of Example 6, the transmission size after puncturing matches the valid RU size.

[0093] 9. In any one of the methods of Examples 1 to 8, the narrowband interferometer (e.g., NB wireless device (17)) uses frequency hopping.

[0094] As will be understood by those skilled in the art, the concepts described herein may be embodied as methods, data processing systems, computer program products, and / or computer storage media storing executable computer programs. Accordingly, the concepts described herein may take the form of embodiments that are entirely hardware, embodiments that are entirely software, or embodiments combining software and hardware aspects, which are generally referred to as "circuits" or "modules" in this specification. Any process, step, operation, and / or function described herein may be performed by and / or associated with a corresponding module that may be implemented in software and / or firmware and / or hardware. Furthermore, the disclosure may take the form of a computer program product on a computer-readable storage medium having computer program code embodied on a medium executable by a computer. Any suitable computer-readable medium having a substance, including a hard disk, CD-ROM, electronic storage device, optical storage device, or magnetic storage device, may be utilized.

[0095] Some embodiments are described herein with reference to flowchart examples and / or block diagrams of methods, systems, and computer program products. It will be understood that each block of the flowchart examples and / or block diagrams, and combinations of blocks within the flowchart examples and / or block diagrams, may be implemented by computer program instructions. Such computer program instructions may be provided to a processor of a general-purpose computer (thereby creating a special-purpose computer), a special-purpose computer, or other programmable data processing device to create a machine, and instructions executed through the processor of the computer or other programmable data processing device accordingly create means for implementing the functions / behaviors specified in the flowchart and / or block diagram blocks or blocks.

[0096] These computer program instructions may also be stored in computer-readable memory or storage media capable of instructing a computer or other programmable data processing device to function in a specific manner, and accordingly, instructions stored in computer-readable memory produce a manufactured article comprising instruction means that implements a function / behavior specified in blocks or blocks of a flowchart and / or block diagram.

[0097] Computer program instructions can also be loaded onto a computer or other programmable data processing device to create a computer-implemented process by causing a series of operational steps to be performed on the computer or other programmable device, and accordingly, instructions executed on the computer or other programmable device provide steps for implementing functions / behaviors specified in blocks or blocks of a flowchart and / or block diagram.

[0098] It should be understood that the functions / actions mentioned in the blocks may occur out of the order mentioned in the operation examples. For example, two blocks depicted consecutively may actually be executed substantially simultaneously, or blocks may sometimes be executed in reverse order depending on the related functions / actions. Although some of the diagrams include arrows on the communication path to show the main direction of communication, it should be understood that communication may occur in the opposite direction to the depicted arrows.

[0099] Computer program code for performing the operation of the concept described herein may be written in an object-oriented programming language such as Python, Java®, or C++. However, computer program code for performing the operation of initiation may also be written in a conventional procedural programming language such as the "C" programming language. The program code may be executed wholly on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer, and partially on a remote computer. In the latter scenario, the remote computer may be connected to the user's computer via a local area network (LAN) or a wide area network (WAN), or a connection to an external computer may be established (e.g., via the Internet using an Internet service provider).

[0100] Many different embodiments have been disclosed in this specification in connection with the above description and drawings. It will be understood that describing and illustrating every combination and subcombination of these embodiments literally would be overly repetitive and obscure. Accordingly, all embodiments may be combined in any manner and / or combination, and this specification, including the drawings, should be interpreted as constituting a complete written description of every combination and subcombination of the embodiments described herein, and of the manner and process of manufacturing and using them, and will support claims for any such combination or subcombination.

[0101] It will be recognized by those skilled in the art that the embodiments described herein are not limited to those specifically illustrated and described above. Furthermore, it should be noted that, unless otherwise stated above, all accompanying drawings are not drawn to scale. Various modifications and variations are possible in light of the above teachings.

[0102] Examples:

[0103] Example A1. As a wideband (WB) wireless device,

[0104] Detect narrowband interference during the listening procedure;

[0105] To perform a subsequent listening procedure, the PHY protocol data unit (PPDU) size is configured to be modified, and the modification is based on the detection of narrowband interference.

[0106] Example A2. In the WB wireless device of Example A1, the PPDU size is modified by at least statically puncturing a plurality of resource units (RU).

[0107] Example A3. In any one of Examples A1 to A2, the WB wireless device may have a PPDU size based at least on channel detection.

[0108] Example A4. In any one of Examples A1 to A3, the listening procedure is a backoff procedure.

[0109] Example A5. In the WB wireless device of Example A4, the PPDU size can be based at least on the previous backoff procedure.

[0110] Example A6. In any one of Examples A1 to A5, the PPDU size is based on the probability that a narrowband interferometer continues to transmit on the same channel and the relative difference in the size of the PPDU after modification.

[0111] Example A7. In any one of Examples A1 to A6, the WB wireless device is an 802.11 WB wireless device.

[0112] Example A8. In any one of Examples A1 to A7, the narrowband interference is based on frequency hopping.

[0113] Example B1. A method implemented by a wideband (WB) wireless device, wherein the method is:

[0114] A step of detecting narrowband interference during a listening procedure; and

[0115] The method includes a step of modifying the size of the PHY protocol data unit (PPDU) to perform a subsequent listening procedure, and the modification is based on the detection of narrowband interference.

[0116] Example B2. In the method of Example B1, the PPDU size is modified by at least statically puncturing a plurality of resource units (RU).

[0117] Example B3. In any one of the methods of Examples B1 to B2, the PPDU size may be based at least on channel detection.

[0118] Example B4. In any one of the methods of Examples B1 to B3, the listening procedure is a backoff procedure.

[0119] Example B5. In the method of Example B4, the PPDU size can be based at least on the previous backoff procedure.

[0120] Example B6. In any one of the methods of Examples B1 to B5, the PPDU size is based on the probability that the narrowband interferometer continues to be transmitted on the same channel and the relative difference in the size of the PPDU after modification.

[0121] Example B7. In any one of the methods of Examples B1 to B6, the WB wireless device is an 802.11 WB wireless device.

[0122] Example B8. In any one of the methods of Examples B1 to B7, narrowband interference is based on frequency hopping.

Claims

Claim 1 A wideband (WB) wireless device (16) configured to operate communication according to a listen-before-talk (LBT) procedure through a plurality of resource units (RUs) forming a main channel and one or more auxiliary channels to transmit a physical protocol data unit (PHY protocol data unit; PPDU) - the PPDU bandwidth is the same as the frequency covered by the RUs for the LBT procedure -; modify the PPDU bandwidth (S136) by removing one or more RUs in the first auxiliary channel when narrowband (NB) interference is present in the first auxiliary channel during the first LBT procedure; perform a subsequent second LBT procedure on the modified PPDU bandwidth; and transmit a PPDU with the modified PPDU bandwidth after the second LBT procedure. Claim 2 A WB wireless device (16) further configured to restore PPDU bandwidth when no NB interfering device is present in the first auxiliary channel during a third LBT procedure following the second LBT procedure. Claim 3 In paragraph 2, the minimum time between the second LBT procedure and the third LBT procedure is set to a first value for latency-sensitive traffic and a second value for traffic not designated as latency-sensitive traffic, and the first value is greater than the second value, WB wireless device (16). Claim 4 A WB wireless device (16), wherein in any one of paragraphs 1 to 3, the LBT procedure is a backoff procedure. Claim 5 A WB wireless device (16) which is an IEEE 802.11 WB wireless device in any one of paragraphs 1 to 4. Claim 6 In claim 5, the removal of the RU includes removing the RU corresponding to the IEEE 802.11 20 MHz channel, WB wireless device (16). Claim 7 In any one of claims 1 to 6, the narrowband interference is based on frequency hopping, WB wireless device (16). Claim 8 A method for a wideband (WB) wireless device (16), comprising: operating communication according to a listen-before-talk (LBT) procedure through a plurality of resource units (RUs) forming a main channel and one or more auxiliary channels to transmit a physical protocol data unit (PPDU) - wherein the PPDU bandwidth is the same as the frequency covered by the RUs for the LBT procedure -; modifying the PPDU bandwidth by removing one or more RUs in the first auxiliary channel when narrowband (NB) interference is present in the first auxiliary channel during the first LBT procedure (S136); performing a subsequent second LBT procedure on the modified PPDU bandwidth; and transmitting a PPDU with the modified PPDU bandwidth after the second LBT procedure. Claim 9 A method according to claim 8, further comprising the step of restoring the PPDU bandwidth when no NB interfering element exists in the first auxiliary channel during a third LBT procedure following the second LBT procedure. Claim 10 In claim 9, the minimum time between the second LBT procedure and the third LBT procedure is set to a first value for latency-sensitive traffic and a second value for traffic not designated as latency-sensitive traffic, wherein the first value is greater than the second value. Claim 11 A method in which, in any one of paragraphs 8 through 10, the LBT procedure is a backoff procedure. Claim 12 A method according to any one of claims 8 to 11, wherein the WB wireless device (16) is an IEEE 802.11 WB wireless device. Claim 13 A method according to claim 12, wherein removing the RU includes removing the RU corresponding to an IEEE 802.11 20 MHz channel. Claim 14 A method according to any one of claims 8 to 13, wherein the narrowband interference is based on frequency hopping.

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