Method and system for LBT threshold setting for directional reception and transmission

Abstract

A method and system for setting LBT or CCA thresholds for directional reception and transmission are provided. In an embodiment, a method for determining whether a channel in an unlicensed frequency band channel of a wireless network is idle in a wireless device includes using the wireless device to detect energy along a first beamforming direction. The method also includes using the wireless device to determine an energy detection threshold. The method also includes using the wireless device to determine whether the unlicensed frequency band channel in at least a first reception direction is idle based on the energy and the energy detection threshold.

Description

[0001] This application claims priority to U.S. Provisional Application No. 62 / 512,547, filed on May 30, 2017, entitled “Method and System for Setting LBT Thresholds for Directional Reception and Transmission,” and U.S. Application No. 15 / 882,439, filed on January 29, 2018, entitled “Method and System for Setting LBT Thresholds for Directional Reception and Transmission,” all of which are incorporated herein by reference in their entirety. Technical Field

[0002] The present disclosure generally relates to a system and method for wireless communication using an unlicensed frequency band, and more particularly to a system and method for determining whether a channel in an unlicensed frequency band is idle. Background Art

[0003] Long Term Evolution (LTE) Licensed Assisted Access (LAA) and WiFi 802.11 both use Carrier Sense Multiple Access / Collision Avoidance (CSMA / CA) when trying to access unlicensed band channels. CSMA / CA consists of two parts: Clear Channel Assessment (CCA) / Listen Before Talk (LBT) and a random backoff mechanism.

[0004] In the Institute of Electrical and Electronics Engineers (IEEE) 802.11 system, fixed energy detection / packet detection (ED / PD) thresholds are used. In 802.11ad, both the Directional Multi-Gigabit (DMG) Ctrl PHY and the conventional DMG physical layer aggregation process protocol data unit (PPDU) use a -68 decibel milliwatt (dBM) threshold for packet detection (PD), and ED uses a threshold of -48dBm. dBm is an abbreviation for the power ratio in decibels (dB) of the measured power relative to one milliwatt (mW). A power level of 0dBm is equivalent to a power of 1 milliwatt. Quasi-omnidirectional antennas are used to measure the channel. Other WiFi systems operating in different frequency bands use similar schemes, but do not necessarily use the same threshold levels.

[0005] In the European Telecommunications Standards Institute (ETSI) European Standard (EN) 302 567, the CCA threshold is related to the maximum transmit power, that is, assuming that the antenna gain is 0 dBi, the energy detection threshold of CCA should be -47 dBm + (40 dBm – P out (dBm). The expression dBi is used to define the gain of an antenna system at RF relative to an isotropic radiator. dBi is an abbreviation for "decibels relative to isotropic". LTE LAA / Enhanced LAA (eLAA) uses a similar scheme but with different values. IEEE802.11ax also introduces a similar scheme as an additional feature to improve spatial reuse.

[0006] The above schemes all assume quasi-omnidirectional antennas. However, directional antennas are increasingly being used to improve the performance of wireless systems. For example, in high frequencies (HF) (e.g., 60 GHz), directional antennas are widely used to enhance the coverage of transmitters and receivers. Since directional antennas are widely used, a channel in one direction may be available, while the same channel in another direction may be unavailable. However, when the same channel in different directions is unavailable, current idle channel assessment methods cannot determine whether a channel in a particular direction is available. Therefore, many advantages of using directional antennas cannot be achieved in current schemes. Summary of the invention

[0007] According to one embodiment of the present disclosure, a method for determining whether a channel in an unlicensed frequency band channel in a wireless network is idle in a wireless device is provided. The method includes using the wireless device to detect energy along a first beamforming direction. The method also includes using the wireless device to determine an energy detection threshold. The method also includes using the wireless device to determine whether the unlicensed frequency band channel is idle in at least a first receiving direction based on the energy and the energy detection threshold.

[0008] According to another embodiment of the present disclosure, a wireless device is provided for determining whether a channel in an unlicensed frequency band channel in a wireless network is idle. The wireless device includes one or more antennas, a detector, a threshold determiner, and a channel state determiner. The detector is coupled to the one or more antennas. The detector is operable to detect energy along a first beamforming direction. The threshold determiner is operable to determine an energy detection threshold. The channel state determiner is operable to determine whether the unlicensed frequency band channel is idle in at least a first receiving direction based on the energy and the energy detection threshold.

[0009] According to another embodiment of the present disclosure, a wireless device for determining whether a channel in an unlicensed frequency band channel in a wireless network is idle is provided. The wireless device includes a non-transitory memory, the non-transitory memory includes instructions and one or more processors communicating with the non-transitory memory. The one or more processors execute instructions. The instructions include detecting energy along a first beamforming direction. The instructions also include determining an energy detection threshold. The instructions also include determining whether the unlicensed frequency band channel is idle in at least a first receiving direction based on the energy and the energy detection threshold.

[0010] According to another embodiment, a method in a wireless device for determining whether a channel in an unlicensed frequency band channel in a wireless network is idle includes detecting energy along a first receive direction using the wireless device. The method also includes determining an energy detection threshold based on an effective EIRP using the wireless device. The effective EIRP is determined based on at least one of an average equivalent isotropic radiated power (EIRP) and a maximum EIRP. The method also includes determining whether the unlicensed frequency band channel is idle in at least the first receive direction based on a comparison of the energy detected along the first receive direction with the energy detection threshold. The EIRP is the product of at least one transmit power of the wireless device and one or more antenna gains of one or more beamforming vectors in a linear domain.

[0011] In one or more of the above embodiments, the energy detection threshold is determined according to at least one of the transmit power of the wireless device or the transmit antenna gain of the wireless device.

[0012] In one or more of the above embodiments, the antenna gain includes the dipole gain and the array gain.

[0013] In one or more of the above embodiments, the effective antenna gain is determined according to the average antenna gain and / or the maximum antenna gain.

[0014] In one or more of the above embodiments, the energy detection threshold is determined according to an average value or a maximum value of the transmitted antenna gain, or an average value or a maximum value of the EIRP after the first time interval.

[0015] In one or more of the above embodiments, the first time interval is at least one listen-before-talk (LBT) time interval or at least one clear channel assessment (CCA) time interval.

[0016] In one or more of the above embodiments, the energy detection threshold is determined according to an average value or a maximum value of the antenna gain or an average value or a maximum value of the EIRP of the wireless device.

[0017] In one or more of the above embodiments, the energy is normalized based on the antenna gain of one or more receiving antennas.

[0018] In one or more of the above embodiments, detecting energy includes performing beam scanning over one or more time slots to detect multiple energies corresponding to multiple receiving directions, wherein each of the one or more time slots corresponds to a different receiving direction.

[0019] In one or more of the above embodiments, detecting energy includes detecting multiple energies in multiple beamforming directions, wherein detection of energy in different receiving directions is staggered in the frequency domain.

[0020] In one or more of the above embodiments, detecting energy includes detecting multiple energies corresponding to multiple receiving directions in parallel.

[0021] In one or more of the above embodiments, the average EIRP of the transmission burst is determined according to:

[0022]

[0023] Among them, k i is the size of the time resource, n i Allocation in resource units, i is the size of the allocated frequency resource, N is the duration of the transmission burst before additional listen-before-talk (LBT) is performed within the channel occupation time (COT), is the transmitted power per time or frequency unit of spatial layer s in the linear domain, is the antenna gain of the beamforming vector for spatial layer s of assignment i in the linear domain.

[0024] In one or more of the above embodiments, the average EIRP of the initial device is determined according to:

[0025]

[0026] Among them, P max is the maximum allowed transmit power of the initial device in the linear domain, is the antenna gain of the initial device available beamforming vector in the linear domain.

[0027] In one or more of the above embodiments, the maximum EIRP of the transmission burst is determined according to:

[0028]

[0029] Among them, k i is the size of the time resource, n i is the allocation in resource units, i is the size of the allocated frequency resource, N is the duration of the transmission burst before additional listen-before-talk (LBT) is performed within the channel occupation time (COT), is the transmitted power per time or frequency unit of spatial layer s in the linear domain, is the antenna gain of the beamforming vector for spatial layer s of assignment i in the linear domain.

[0030] In one or more of the above embodiments, the maximum EIRP of the initial device is determined according to:

[0031]

[0032] Among them, P maxis the maximum allowed transmit power of the initial device in the linear domain, is the antenna gain of the initial device available beamforming vector in the linear domain.

[0033] In one or more of the above embodiments, the method includes initiating a burst after a successful listen-before-talk (LBT), wherein the energy detection threshold is set based on an average EIRP or a maximum EIRP of the burst.

[0034] In one or more of the above embodiments, the wireless device extends the current continuous transmission burst without performing additional LBT when the average or maximum EIRP of the allocation including the extension does not exceed the average EIRP or maximum EIRP of the transmitter when contending for the channel.

[0035] In one or more of the above embodiments, when the average EIRP or maximum EIRP of the allocation including the extension exceeds the average or maximum EIRP when the transmitter is used to contend for the channel, the wireless device performs another LBT before continuing to transmit the extension portion.

[0036] In one or more of the above embodiments, the average EIRP comprises a weighted average of multiple EIRPs corresponding to each resource allocation in a subsequent burst, wherein a weighting factor of each EIRP is associated with a portion of resources in the burst in at least one of the time domain, the frequency domain, and the spatial domain.

[0037] In one or more of the above embodiments, the average EIRP of the device is an average of a plurality of allowed EIRPs of the initial device.

[0038] In one or more of the above embodiments, the maximum EIRP includes the maximum value of multiple EIRPs of each resource allocation in the subsequent burst. When multiple resource allocations are multiplexed in the frequency domain of the same time unit, the EIRPs of the resource allocations multiplexed in the frequency domain of the same time unit should be summed in the linear domain. Then, the maximum value is performed between the multiple EIRPs corresponding to each time unit.

[0039] In one or more of the above embodiments, the maximum EIRP of the device is the maximum value of all allowed EIRPs of the initial device.

[0040] In one or more of the above embodiments, when the effective EIRP of the allocation including the extension exceeds the effective EIRP when the transmitter was contending for the channel, the wireless device performs another LBT before continuing to transmit the extension portion.

[0041] An advantage of one or more embodiments of the present disclosure is reduced interference. In addition, in one or more embodiments, when directional antennas are used on the transmitter and / or receiver, the signal to interference and noise ratio (SINR) on the receiver side is not reduced. In addition, in one or more embodiments, the reduced interference ensures that there are more spatial sharing opportunities between nodes sharing the same unlicensed frequency band. In addition, in one or more embodiments, the joint CCA of all potential receiving directions helps to alleviate the hidden node problem. The energy detection (ED) threshold related to the effective antenna gain supports transmitters with larger antenna gain (i.e., narrow beam). In addition, in one or more embodiments, the disclosed method reduces interference in non-expected areas while maintaining a given SINR on the receiver side. In addition, in one or more embodiments, the reduced interference ensures that there are more spatial sharing opportunities between nodes sharing the same unlicensed frequency band. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] In order to more fully understand the present invention and its advantages, reference is now made to the following detailed description, which is illustrated in conjunction with the accompanying drawings:

[0043] Figure 1 An embodiment network for transmitting data in which the disclosed methods and systems may be implemented is shown;

[0044] Figure 2 is a diagram of an embodiment of a system according to a first option for channel sensing using directional antennas;

[0045] Figure 3 is a diagram of an embodiment of a system according to a second option for channel sensing using directional antennas;

[0046] Figure 4 is a diagram of an embodiment of a system according to a third option for channel sensing using directional antennas;

[0047] Figure 5 is a diagram of an alternative embodiment of a system according to the third option of channel sensing using directional antennas;

[0048] Figure 6 A diagram of an example embodiment of a transmission burst after LBT, including multiple consecutive resource allocations in the time domain;

[0049] Figure 7 is a diagram of an example embodiment of multiple resource allocation in the frequency domain;

[0050] Figure 8 A diagram of an example embodiment of a transmission burst after LBT, including a combination of a control channel and multiple consecutive resource allocations in the time-frequency domain;

[0051] Fig. 9A diagram of an example embodiment in which a transmission burst after LBT can be extended without additional LBT;

[0052] Fig.10 is a diagram of an example embodiment when a transmission burst should be interrupted;

[0053] Fig.11 A flow chart of an embodiment of a method for determining whether a channel in an unlicensed frequency band is idle;

[0054] Fig.12 A flow chart of an embodiment of a method for determining whether a channel in an unlicensed frequency band is idle;

[0055] Fig.13 A flow chart of an embodiment of a method for determining whether a channel in an unlicensed frequency band is idle;

[0056] Fig.14 A flow chart of an embodiment of a method for determining whether a channel in an unlicensed frequency band is idle;

[0057] Fig.15 A flow chart of an embodiment of a method for determining whether a channel in an unlicensed frequency band is idle;

[0058] Fig.16 is a block diagram of an embodiment of a system for determining whether an unlicensed frequency band channel is idle using directional reception and / or transmission;

[0059] Fig.17 A block diagram of an embodiment processing system for performing the methods described herein is shown;

[0060] Fig.18 A block diagram of a transceiver suitable for sending and receiving signaling in a telecommunications network is shown. DETAILED DESCRIPTION

[0061] The making and use of various embodiments are discussed in detail below. However, it should be understood that the present disclosure provides many applicable inventive concepts that can be embodied in various specific contexts. The specific embodiments discussed are only to illustrate the specific ways to make and use the present invention, and do not limit the scope of the present invention.

[0062] Disclosed herein are systems, apparatus, and methods for setting CCA or LBT thresholds when a transmitter and / or receiver uses directional transmit / receive antennas. Also disclosed herein are systems, apparatus, and methods for energy detection and adjusting CCA thresholds when one or more directional antennas are used on a transmitter and / or receiver. Directional transmission / reception may be achieved by (one or more) directional antennas or antenna array beamforming. In one embodiment, the initial device detects energy P rThe initial device detects the energy P r The level of the energy detection threshold is compared to the energy detection threshold. When transmitting, the energy detection threshold applies to the transmit power and the effective transmit antenna gain. In one embodiment, the effective transmitter antenna gain may not be exactly the same as the antenna gain of the hardware. The effective transmitter gain may depend on one or more narrow antenna gains, the number of antennas, the beamforming vector, and other factors.

[0063] In one embodiment, when directional reception is used, channel sensing is performed by a collocated transmit and receive point (TRP) zone using a quasi-omnidirectional beam. As used herein, the term "zone" refers to a service coverage area provided by an evolved NodeB (eNB). CCA is performed separately, and the decision to transmit is based on the CCA results of one or more TRPs. In another embodiment, when directional reception is used, the beam scans each of multiple directions in each time slot using analog beamforming to perform channel sensing. In another embodiment, the coverage area is divided into multiple directions, and in a single time slot using digital beamforming, channel sensing is performed using multiple parallel sensing in multiple directions. In another embodiment, sensing of different beams using digital beamforming is interleaved in the frequency domain.

[0064] In one embodiment, the detected energy is normalized. In one embodiment, the detected energy is normalized by dividing the detected energy by the antenna gain of the receiving antenna. For example, if the detected energy is -40 dBm and the antenna gain of the receiving antenna is 20 dBi, the normalized detected energy is -60 dBm.

[0065] An advantage of one or more embodiments of the present disclosure is reduced interference. In addition, in one or more embodiments, when directional antennas are used at the transmitter and / or receiver, the signal to interference and noise ratio (SINR) on the receiver side is not reduced. In addition, in one or more embodiments, the reduced interference ensures that there are more spatial sharing opportunities between nodes sharing the same unlicensed frequency band. In addition, in one or more embodiments, the joint CCA of all potential receiving directions helps to alleviate the hidden node problem. The ED threshold related to the effective antenna gain supports transmitters with larger antenna gain (i.e., narrow beam). In addition, in one or more embodiments, the disclosed method reduces interference in non-expected areas while maintaining a given SINR on the receiver side. In addition, in one or more embodiments, the reduced interference ensures that there are more spatial sharing opportunities between nodes sharing the same unlicensed frequency band.

[0066] Figure 1An embodiment network 100 for transmitting data is shown, in which the disclosed methods and systems can be implemented. The network 100 includes multiple network components. The network components may include access points (APs), user equipment (UEs), or any other wireless receiving points. In one embodiment, the network 100 includes an access point (AP) 110 with a coverage area 112, multiple UEs 120-122, and a backhaul network 130. In various embodiments, the AP 110 may be a transmission and reception point (TRP), a base station (BS), a base transceiver station (BTS), an eNodeB (eNB), a next generation base station NodeB (sometimes referred to as a gNB), a wireless router, etc. Therefore, the AP 110 may include any component capable of providing wireless access, especially by establishing an uplink (dashed line) and / or downlink (dotted line) connection with the UE 120-122. The UE 120-122 may include any component capable of establishing a wireless connection with the AP 110. Examples of UEs 120-122 include mobile phones, tablets, and laptops. Backhaul network 130 may be any component or collection of components that allows data to be exchanged between AP 110 and a remote end (not shown). In some embodiments, network 100 may include various other wireless devices, such as relays, femtocells, and the like.

[0067] Components in network 100 may communicate using unlicensed band channels. To transmit on an unlicensed band, each of UE 120-122 and AP 110 must determine whether the channel is idle or occupied, for example, by CCA or LBT. In one embodiment, one or more of UE 120-122 and AP 110 include directional antennas (or perform transmit / receive beamforming) to increase the coverage of the transmitter and receiver. The initial device (e.g., one of UE 120-122 or AP 110) detects the energy of the AP 110 through the P r In one embodiment, the antenna gain at the receiver side is assumed to be 0 dBi. In one embodiment, the energy detection P r In all receive directions. The initial device will P r In one embodiment, when the initial device sends, the energy detection threshold (ED thrd ) is dynamically determined based on the transmit power and / or based on the transmitter antenna gain. If the detected energy is less than the energy detection threshold, the initiating device determines that the channel is idle and can continue to transmit. In one embodiment, the channel may be idle in one direction but not in another. In this case, the initiating device may transmit in the direction where the channel is idle, but not in the direction where the channel is not idle.

[0068] In one embodiment, the potential transmitter will detect the energy P r is compared with an energy detection threshold. In one aspect, the energy detection threshold is adaptive to the transmit power and effective TX antenna gain in subsequent transmissions. Thus, in one aspect, the ED thrd =X+Y-min(Y,P out +a*G TX ), where the unit is dBm. “X” is a predefined parameter related to the CCA level, such as -47 or -48dBm. “Y” is a predefined parameter related to the maximum equivalent isotropic radiated power (EIRP) limit, such as 40dBm in an indoor environment. “P out " is the transmission power. "G TX ” is the effective transmit antenna gain at the originating device. “a” is a parameter that provides an advantage to devices with larger antenna gain. In one aspect, when a=1, P out +a*G TX Equal to EIRP.

[0069] In a first embodiment, the ED is derived from the maximum value of the antenna gain within the burst immediately following the LBT or the channel occupancy time (COT) transmission. thrd The antenna gain includes the dipole factor and the array factor. In one embodiment, the dipole factor and the array factor are provided in dB. The dipole factor, f T , is derived from the radiation pattern in the transmit direction. The array factor, W TX , derived from the beamforming vector. If only one antenna element is used for transmission, then is the beamforming vector used in the subsequent COT. The effective antenna gain, G TX ,in accordance with is determined. Assume that J beamforming vectors are used in MCOT. In one embodiment, the ED threshold is derived based on the maximum transmit antenna gain of the initial device. In this case, is available at the initial device, and the effective transmit antenna gain at the initial device is

[0070] The beamforming vector of a phased antenna array is defined as w v is a vector of length m, w h is a vector of length n. v Each item in

[0071]

[0072] w h Each item in

[0073] Given

[0074] Generate DFT beam candidates based on uniform vertical and horizontal angle distribution, for example, M = N = 4, The array gain is normalized by the input energy of the antenna array to 10log 10 (MN). In one aspect, the array gain is as follows. Table 1 below is an example of an antenna pattern. One "X" corresponds to a pair of cross-polarized antennas. "M" is the number of rows of the planar antenna array, and "N" is the number of columns of the planar antenna array. In Table 1, there are a total of 2xMxN antenna elements.

[0075]

[0076] Table 1

[0077] Table 2 below shows examples of beam gains for beam IDs and beam directions. The values ​​in Table 2 are calculated according to equations defined in IEEE 802.11-09 / 0334r8, which is incorporated herein by reference as if reproduced in its entirety.

[0078]

[0079] Table 2

[0080] In one aspect, assuming M=N=4, if the array gain is normalized by the radiated energy of the array, the array gain is obtained as shown in Table 3 below.

[0081]

[0082] Table 3

[0083] Assuming M=4, N=8, if the array gain is normalized by the radiation energy of the array, the array gain is obtained as shown in Table 4 below.

[0084]

[0085] Table 4

[0086] Assuming M=N=8, if the array gain is normalized by the radiation energy of the array, the array gain is obtained as shown in Table 5 below.

[0087]

[0088] Table 5

[0089] In one embodiment, the effective antenna gain may also include a factor in dB related to the relative beam width. For example, the effective antenna gain may be defined as The relative beam width is Where A is the solid angle with an antenna gain greater than a predetermined threshold, such as 0 dBi. In one embodiment, the effective antenna gain is determined by the average antenna gain of multiple beamforming vectors according to:

[0090]

[0091] Among them, k i is the size of the time resource, n i is the allocation in resource units, i is the size of the allocated frequency resource, N is the duration of the transmission burst before additional listen-before-talk (LBT) during the channel occupation time (COT), S i is the number of spatial layers of resource allocation i, and is the antenna gain of the beamforming vector of spatial layer s assigned i in the linear domain. In one embodiment, the effective antenna gain is determined by the average of the antenna gains of the available beamforming vectors of the device according to:

[0092]

[0093] in, is the antenna gain of the initial device available beamforming vector in the linear domain.

[0094] The use of directional sensing by the initial device increases the possibility of hidden nodes. In one embodiment, when directional antennas are used, one of the following methods is used for channel sensing.

[0095] Figure 2 2 is a diagram of an embodiment of a system according to the first option of using directional antennas for channel sensing. In system 200, as shown, joint CCA is performed on juxtaposed TRPs, each TRP serving a corresponding one of zones B1, B2, and B3 with a wider / quasi-omnidirectional beam. In one embodiment, the area to be covered for channel sensing is divided into wide zones B1, B2, and B3, and each beam covers one of zones B1, B2, and B3, respectively. In the described example, each zone B1, B2, and B3 occupies 120 degrees of the total area. In other embodiments, the area may be divided into multiple or fewer zones. Channel sensing in each zone B1, B2, and B3 is performed almost simultaneously. In one embodiment, three antenna arrays are used to serve three zones B1, B2, and B3, and each antenna array covers one of zones B1, B2, and B3. In other embodiments, other numbers of zones and antenna arrays may be used, each zone being served by its own antenna array. In one embodiment, each antenna array may be a single antenna.

[0096] Figure 33 is a diagram of an embodiment of a system 300 according to a second option for channel sensing using directional antennas. In the system 300, channel sensing is performed by beam scanning on each one or more time slots to detect multiple energy levels corresponding to multiple beamforming directions. Each beam covers a sub-area of ​​the total 360 degrees of the area to be covered. In the depicted example, each beam covers a 30 degree range. However, in other embodiments, the area may be divided into larger or smaller beams. Each of the one or more time slots corresponds to a different receive direction. In one embodiment, channel sensing uses analog beamforming.

[0097] Figure 4 4 is a diagram of an embodiment of a system according to the third option of using directional antennas for channel sensing. In system 400, multiple parallel sensing is performed, where in each time slot, channel sensing is performed for multiple directions. In one embodiment, channel sensing uses digital beamforming.

[0098] Figure 5 is a diagram of an alternative embodiment of a system 500 according to the third option of channel sensing using directional antennas. In the system 500, sensing of different beams is interleaved in the frequency domain.

[0099] In another embodiment, the ED threshold may be derived based on the maximum transmit power of the originating device.

[0100] In another embodiment, the ED threshold is derived based on the maximum transmit power after LBT.

[0101] In another embodiment, the initial device determines the channel status (busy or idle) based on multiple CCA results from different directions. For example, if the channel perception along the transmission direction is idle, the transmission channel is considered to be idle. In another example, if more than X% of the directional CCA results including the transmission direction are idle, then the channel can be considered to be idle. In another example, if the CCA in the direction including the transmission direction and the reverse direction is idle, then the channel can be considered to be idle. In one aspect, the initial device compares the maximum value or average value of multiple CCA results from different directions with a threshold. The maximum or average CCA can be performed on the CCA result in the direction of interest.

[0102] In one embodiment, assuming the EIRP at the original device is the same, G TX The term is weighted toward devices with larger transmit antenna gain (i.e., narrow beam). In one embodiment, “G TX The parameter "a" in front of the "" item is less than 1, for example 0.5.

[0103] In one aspect, the ED threshold is derived based on the maximum antenna gain of the originating device, where:

[0104]

[0105] In one aspect, the ED threshold is derived based on the maximum value of the antenna gain after LBT given by:

[0106]

[0107] Where j is the index of the resource configuration.

[0108] Figure 6 600 is a diagram of an example embodiment of a transmission burst after LBT, including multiple consecutive resource allocations in the time domain. The transmission direction in at least one resource allocation is different from the other resource allocations. The arrows in the blocks represent the transmission direction of the corresponding resource allocation in the transmission burst. Multiple arrows in a block represent multiple layers in a resource allocation.

[0109] Figure 7 Diagram 700 of an example embodiment of multiple resource allocations in the frequency domain. At least one resource allocation has a different transmission direction than the other resource allocations. Arrows in the blocks indicate the transmission direction of the corresponding resource allocations in a transmission burst.

[0110] Figure 8 800 is a diagram of an example embodiment of a transmission burst after LBT, including a combination of one or more control channels and multiple contiguous resource allocations in the time-frequency domain. In one aspect, the gNB uses different beamforming for the control channels than for the data channels. The arrows in the blocks indicate the transmission direction of the corresponding resource allocation in the transmission burst. Multiple arrows in a block indicate multiple layers in a resource allocation.

[0111] In one embodiment, the ED threshold is based on the average EIRP of subsequent transmission bursts, and the ED thrd =X+Y-min(Y, Average(EIRP)). The average EIRP of the transmission burst is calculated by the following equation:

[0112]

[0113] Among them, k i is the size of the time resource, n i is the allocation in resource units, i is the size of the allocated frequency resource, N is the duration of the transmission burst before additional LBT is performed within the channel occupation time (COT), is the transmit power per T / F unit of spatial layer s in the linear domain (i.e., in linear units such as mW, as opposed to logarithmic units such as dBm), is the antenna gain of the beamforming vector for spatial layer s of assignment i in the linear domain.

[0114] In one aspect, there are multiple allocations with different beamforming vectors in a transmission burst. In one aspect, the time unit is an OFDM symbol, a time slot, a subframe, etc. In one aspect, the frequency resource unit is a physical resource block group (PRG), a resource block group (RBG), a subband, or a channel. In some allocations, multiple spatial layers are configured. In one aspect, the average value of EIRP provides resources for control, reference signal (RS), and data.

[0115] In one aspect, the average EIRP of the initial equipment is determined according to:

[0116]

[0117] Among them, P max is the maximum allowed transmit power of the initial device in the linear domain, is the antenna gain of the initial device available beamforming vector in the linear domain.

[0118] In one or more of the above embodiments, the maximum EIRP of the transmission burst is determined according to:

[0119]

[0120] Among them, k i is the size of the time resource, n i is the allocation in resource units, i is the size of the allocated frequency resource, N is the duration of the transmission burst before additional LBT is performed within the channel occupation time (COT), is the transmitted power per time or frequency unit of spatial layer s in the linear domain. is the antenna gain of the beamforming vector for spatial layer s of assignment i in the linear domain.

[0121] In one or more of the above embodiments, the maximum EIRP of the initial device is determined according to:

[0122]

[0123] Among them, P max is the maximum allowed transmit power of the initial device in the linear domain, is the antenna gain of the device's available beamforming vector in the linear domain.

[0124] In one aspect, when the ED threshold under consideration of extension is higher than the ED threshold of the ongoing burst for channel access, the transmitter extends the current continuous transmission burst without additional LBT. Equivalently, the average / maximum EIRP under consideration of the allocation in extension should not exceed the average / maximum EIRP when the transmitter is used to contend for the channel. Otherwise, a new burst should be started after a successful LBT, where the ED threshold is set by the average EIRP of the new burst.

[0125] Fig. 9 900 is a diagram of an example embodiment when a transmission burst after LBT can be extended without additional LBT. The ED threshold used in the LBT before the original transmission burst is based on the effective antenna gain or effective EIRP of the resource allocations from n1 to n5. If the effective antenna gain or effective EIRP of the extended portion (resource allocations n6 to n8) is not greater than that of n1 to n5 (or the effective antenna gain or effective EIRP of the resource allocations including n1 to n8 is not greater than that of n1 to n5), the initial device can continuously transmit n6 to n8 without any interruption or LBT.

[0126] Fig.10 1000 is a diagram of an example embodiment when a transmission burst is interrupted. If the effective antenna gain or effective EIRP from resource allocations n6 to n8 is greater than the effective antenna gain or effective EIRP from n1 to n5 (or, including the effective antenna gain or effective EIRP from n1 to n8 resource allocations is greater than the effective antenna gain or effective EIRP from n1 to n5), the ongoing burst is not extended. Additional LBT is required before transmission from n6 to n8 is performed.

[0127] Fig.11 Flowchart of an embodiment of a method 1100 for determining whether a channel in an unlicensed frequency band is idle. The method begins at block 1102, where energy along one or more receive directions is determined. At block 1104, an energy detection threshold is determined based on (one or more) transmit powers and / or (one or more) antenna gains of a transmission of the wireless device. At block 1106, it is determined whether the unlicensed frequency band is idle based on the energy and the energy detection threshold, after which the method 1100 may end.

[0128] Fig.12A flow chart of an embodiment of a method 1200 for determining whether a channel in an unlicensed frequency band is idle. The method 1200 begins at block 1204, where a joint CCA channel sensing is performed across directional regions using a quasi-omnidirectional beam. At block 1206, a determination is made as to whether the channel is idle based on the results of the CCA channel sensing, after which the method 1200 may end. Each directional region covers an angular subset of 360 degrees around the initial device.

[0129] Fig.13 A flow chart of an embodiment of a method 1300 for determining whether a channel in an unlicensed frequency band is idle. The method 1300 begins at block 1304, where a beam scan of a directional area is performed in each time slot assuming analog beamforming to perform channel sensing. At 1306, it is determined whether the channel is idle based on the channel sensing result, after which the method 1300 may end.

[0130] Fig.14 A flow chart of an embodiment of a method 1400 for determining whether a channel in an unlicensed frequency band is idle. The method 1400 begins at block 1404, where multiple parallel channel sensing is performed for multiple directional areas in each time slot using digital beamforming. At 1406, it is determined whether the channel is idle based on the results of the channel sensing, after which the method 1400 may end.

[0131] Fig.15 A flow chart of an embodiment of a method 1500 for determining whether a channel in an unlicensed frequency band is idle. The method 1500 begins at block 1504, where sensing of different beams using digital beamforming is interleaved in the frequency domain. At 1506, it is determined whether the channel is idle based on the results of the channel sensing, after which the method 1500 may end.

[0132] Fig.161 is a block diagram of an embodiment of a system 1600, which is used to determine whether an unlicensed frequency band channel is idle using directional reception and / or transmission. The system 1600 includes one or more antennas 1602, a transceiver 1604, a detector 1606, a threshold determiner 1608, and a channel state determiner 1610. The one or more antennas 1602 may include a directional antenna or may include an antenna array that can be used for analog or digital beamforming. The transceiver 1604 is used to send and receive signals through the antenna 1602. The detector 1606 is connected to the antenna 1602 through the transceiver 1604. The detector is used to detect energy along various reception directions and can be operated to implement the detection part of the above-mentioned embodiment. The threshold determiner 1608 and the channel state determiner 1610 are connected to the detector 1606. The threshold determiner 1608 is used to determine the energy detection threshold according to at least one of the one or more transmission powers of the wireless device or the one or more transmission antenna gains of the wireless device. The channel state determiner 1608 is configured to determine whether the unlicensed frequency band channel is idle in at least one receive direction based on the energy and the energy detection threshold. The threshold determiner 1608 and the channel state determiner 1610 are operable to implement portions of any of the above embodiments. In one embodiment, the detector 1606, the threshold determiner 1608, and at least some portions of the channel state determiner are implemented in software. In one embodiment, the detector 1606, the threshold determiner 1608, and at least some portions of the channel state determiner are implemented in hardware.

[0133] Fig.17 1 shows a block diagram of an embodiment processing system 1700 for performing the methods described herein, which may be installed in a host device, such as, Figure 1 1700 includes a processor 1704, a memory 1706, and interfaces 1710-1714, which may (or may not) be used as Fig.17Arranged as shown. Processor 1704 may be any component or collection of components suitable for performing computing and / or other processing-related tasks, and memory 1706 may be any component or collection of components suitable for storing programs and / or instructions executed by processor 1704. In one embodiment, memory 1706 includes a non-transitory computer-readable medium. Interfaces 1710, 1712, 1714 may be any component or collection of components that allow processing system 1700 to communicate with other devices / components and / or users. For example, one or more of interfaces 1710, 1712, 1714 may be suitable for transmitting data, control or management messages from processor 1704 to applications installed on a host device and / or a remote device. As another example, one or more of interfaces 1710, 1712, 1714 may be suitable for allowing a user or user device (e.g., a personal computer (PC), etc.) to interact / communicate with processing system 1700. Processing system 1700 may include Fig.17 Additional components not described herein, such as long-term storage (eg, non-volatile memory, etc.).

[0134] In some embodiments, the processing system 1700 is included in a network device that is accessing a telecommunications network, or is part of a telecommunications network. In one example, the processing system 1700 is located in a network-side device in a wireless or wired telecommunications network, such as a base station, a relay station, a scheduler, a controller, a gateway, a router, an application server, or any other device in the telecommunications network. In other embodiments, the processing system 1700 is located in a user-end device that accesses a wireless or wired telecommunications network, such as a mobile station, a user equipment (UE), a personal computer (PC), a tablet computer, a wearable communication device (such as a smart watch, etc.), or any other device suitable for accessing a telecommunications network.

[0135] In some embodiments, one or more of interfaces 1710, 1712, 1714 connects processing system 1700 to a transceiver suitable for sending and receiving signaling in a telecommunications network.

[0136] Fig.18 1 shows a block diagram of a transceiver 1800 suitable for sending and receiving signaling in a telecommunications network. The transceiver 1800 may be installed in a host device, for example, Figure 1Any one of UE 120-122 and / or AP 110 in the network. As shown in the figure, transceiver 1800 includes network side interface 1802, coupler 1804, transmitter 1806, receiver 1808, signal processor 1810 and device side interface 1812. Network side interface 1802 may include any component or component set suitable for sending or receiving signaling in a wireless or wired telecommunications network. Coupler 1804 may include any component or component set suitable for facilitating two-way communication through network side interface 1802. Transmitter 1806 may include any component or component set (e.g., up converter, power amplifier, etc.) suitable for converting baseband signals into modulated carrier signals suitable for transmission through network side interface 1802. Receiver 1808 may include any component or component set (e.g., down converter, low noise amplifier, etc.) suitable for converting carrier signals received through network side interface 1802 into baseband signals. The signal processor 1810 may include any component or collection of components suitable for converting baseband signals into data signals suitable for communication through the device-side interface(s) 1812, and vice versa. The device-side interface(s) 1812 may include any component or collection of components suitable for transmitting data signals between the signal processor 1810 and components within a host device (e.g., the processing system 1700, a local area network (LAN) port, etc.).

[0137] The transceiver 1800 can send and receive signaling through any type of communication medium. In some embodiments, the transceiver 1800 sends and receives signaling through a wireless medium. For example, the transceiver 1800 can be a wireless transceiver suitable for communicating according to a wireless telecommunication protocol, such as a cellular protocol (e.g., Long Term Evolution (LTE)), a wireless local area network (WLAN) protocol (e.g., Wi-Fi, etc.), or any other type of wireless protocol (such as Bluetooth, near field communication (NFC), etc.). In the embodiment, the network side interface 1802 includes one or more antennas / radiating elements. For example, the network side interface 1802 may include a single antenna, multiple separate antennas, or a multi-antenna array for multi-layer communication, such as single input multiple output (SIMO), multiple input single output (MISO), multiple input multiple output (MIMO), etc. In other embodiments, the transceiver 1800 sends and receives signals through a wired medium, such as a twisted pair, a coaxial cable, an optical fiber, etc. A specific processing system and / or transceiver may use all of the components shown, or only a subset of the components, and the level of integration may vary from device to device.

[0138] According to one embodiment of the present disclosure, a method in a wireless device is provided for determining whether a channel in an unlicensed frequency band channel in a wireless network is idle. The method includes using a wireless device to detect energy along a first beamforming direction. The method also includes using the wireless device to determine an energy detection threshold based on at least one of one or more transmit powers of the wireless device or one or more antenna gains of the wireless device. The method also includes using the wireless device to determine whether the unlicensed frequency band channel is idle in at least the first receiving direction based on the energy and the energy detection threshold.

[0139] According to another embodiment of the present disclosure, a wireless device is provided for determining whether a channel in an unlicensed frequency band channel in a wireless network is idle. The wireless device includes one or more antennas, a detector, a threshold determiner, and a channel state determiner. The detector is coupled to the one or more antennas. The detector is operable to detect energy along a first beamforming direction. The threshold determiner is operable to determine an energy detection threshold based on at least one of one or more transmit powers of the wireless device or one or more transmit antenna gains of the wireless device. The channel state determiner is operable to determine whether the unlicensed frequency band channel is idle in at least a first receive direction based on the energy and the energy detection threshold.

[0140] According to another embodiment of the present disclosure, a wireless device is provided for determining whether a channel in an unlicensed frequency band channel of a wireless network is idle. The wireless device includes a non-transitory memory, the non-transitory memory including instructions and one or more processors communicating with the non-transitory memory. One or more processors execute instructions. The instructions include detecting energy along a first beamforming direction. The instructions also include determining an energy detection threshold based on at least one of (one or more) transmit powers of the wireless device or (one or more) antenna gains of the wireless device's transmission. The instructions also include determining whether the unlicensed frequency band channel is idle in at least a first receive direction based on the energy and the energy detection threshold.

[0141] In one or more of the above embodiments, the energy detection threshold is determined according to at least one of the transmit power of the wireless device or the transmit antenna gain of the wireless device.

[0142] In one or more of the above embodiments, the antenna gain includes the dipole gain and the array gain.

[0143] In one or more of the above embodiments, the energy detection threshold is determined according to the maximum value of the antenna gain transmitted after the first time interval.

[0144] In one or more of the above embodiments, the first time interval includes at least one listen-before-talk (LBT) time interval or at least one clear channel assessment (CCA) time interval.

[0145] In one or more of the above embodiments, the energy detection threshold is determined according to the maximum antenna gain of the wireless device.

[0146] In one or more of the above embodiments, detecting energy includes detecting energy in multiple receiving directions.

[0147] In one or more of the above embodiments, the energy is normalized based on the antenna gain of one or more receiving antennas.

[0148] In one or more of the above embodiments, detecting energy includes performing beam scanning over one or more time slots to detect multiple energies corresponding to multiple receiving directions, wherein each of the one or more time slots corresponds to a different receiving direction.

[0149] In one or more of the above embodiments, detecting energy includes detecting multiple energies in multiple beamforming directions, wherein energy detections in different receiving directions are interleaved in the frequency domain.

[0150] In one or more of the above embodiments, detecting energy includes detecting multiple energies corresponding to multiple receiving directions in parallel.

[0151] According to another embodiment, a method in a wireless device for determining whether a channel in an unlicensed frequency band channel in a wireless network is idle includes detecting energy along a first receive direction using the wireless device. The method also includes determining an energy detection threshold based on an effective EIRP using the wireless device. The effective EIRP is determined based on at least one of an average equivalent isotropic radiated power (EIRP) and a maximum EIRP. The method also includes determining whether the unlicensed frequency band channel is idle in at least the first receive direction based on a comparison of the energy detected along the first receive direction with the energy detection threshold. The EIRP is a product of at least one transmit power of the wireless device and one or more antenna gains of one or more beamforming vectors in a linear domain.

[0152] In one or more of the above embodiments, the effective antenna gain is determined according to the average antenna gain and / or the maximum antenna gain.

[0153] In one or more of the above embodiments, the energy detection threshold is determined according to an average value or a maximum value of the antenna gain after the first time interval, or an average value or a maximum value of the transmitted EIRP.

[0154] In one or more of the above embodiments, the first time interval is one of a listen-before-talk (LBT) or a clear channel assessment (CCA) time interval.

[0155] In one or more of the above embodiments, the energy detection threshold is determined according to the maximum antenna gain of the wireless device.

[0156] In one or more of the above embodiments, detecting energy includes detecting energy in multiple receiving directions.

[0157] In one or more of the above embodiments, the energy is normalized according to the antenna gain of one or more receiving antennas.

[0158] In one or more of the above embodiments, detecting energy includes performing beam scanning in one or more time slots to detect multiple energies corresponding to multiple receiving directions, wherein each of the one or more time slots corresponds to a different receiving direction.

[0159] In one or more of the above embodiments, detecting energy includes detecting multiple energies in multiple beamforming directions, wherein the detection of energy in different receiving directions is interleaved in the frequency domain.

[0160] In one or more of the above embodiments, the detecting energy includes detecting multiple energies corresponding to multiple receiving directions in parallel.

[0161] In one or more of the above embodiments, the method includes determining at least one of an average EIRP and a maximum EIRP.

[0162] In one or more of the above embodiments, the average EIRP comprises a weighted average of multiple EIRPs corresponding to each resource allocation in a subsequent burst, wherein a weighting factor of each EIRP is associated with a portion of resources in the burst in at least one of the time domain, the frequency domain, and the spatial domain.

[0163] In one or more of the above embodiments, the average EIRP of the device is an average of a plurality of allowed EIRPs of the original device.

[0164] In one or more of the above embodiments, the maximum EIRP includes the maximum value of multiple EIRPs of each resource allocation in the subsequent burst. When multiple resource allocations are multiplexed in the frequency domain of the same time unit, the EIRPs of the resource allocations multiplexed in the frequency domain of the same time unit should be summed in the linear domain. Then, the maximum value is performed between the multiple EIRPs corresponding to each time unit.

[0165] In one or more of the above embodiments, the maximum EIRP of the device is the maximum value of all allowed EIRPs of the original device.

[0166] In one or more of the above embodiments, the average EIRP is determined according to:

[0167]

[0168] Among them, k i is the size of the time resource, n iis the allocation in resource units, i is the size of the allocated frequency resource, N is the duration of the transmission burst before additional LBT is performed within the channel occupation time (COT), is the transmitted power per time or frequency unit of spatial layer s in the linear domain, is the antenna gain of the beamforming vector for spatial layer s of assignment i in the linear domain.

[0169] In one or more of the above embodiments, the average EIRP is the average EIRP of the burst, which is determined as follows:

[0170]

[0171] Among them, k i is the size of the time resource, n i is the allocation in resource units, i is the size of the allocated frequency resource, N is the duration of the transmission burst before additional listen-before-talk (LBT) is performed within the channel occupation time (COT), is the transmitted power per time or frequency unit of spatial layer s in the linear domain, is the antenna gain of the beamforming vector for spatial layer s of assignment i in the linear domain.

[0172] In one or more of the above embodiments, the average EIRP is the average EIRP of the initial device, and the average EIRP of the initial device is determined according to:

[0173]

[0174] Among them, P max is the maximum allowed transmit power of the initial device in the linear domain, is the antenna gain of the device's available beamforming vector in the linear domain.

[0175] In one or more of the above embodiments, the maximum EIRP is the maximum EIRP of the transmission burst, wherein the maximum EIRP of the transmission burst is determined according to:

[0176]

[0177] Among them, k i is the size of the time resource, n i is the allocation in resource units, i is the size of the allocated frequency resource, and N is the duration of the transmission burst before additional listen-before-talk (LBT) is performed within the channel occupation time (COT). is the transmitted power per time or frequency unit of spatial layer s in the linear domain. is the antenna gain of the beamforming vector for spatial layer s of assignment i in the linear domain.

[0178] In one or more of the above embodiments, the maximum EIRP is the maximum EIRP of the device, wherein the maximum EIRP of the device is determined according to:

[0179]

[0180] Among them, P max is the maximum allowed transmit power of the initial device in the linear domain, is the antenna gain of the device's available beamforming vector in the linear domain.

[0181] In one or more embodiments described above, the method includes initiating a burst after a successful listen-before-talk (LBT), wherein the energy detection threshold is set based on an average EIRP of the burst.

[0182] In one or more of the above embodiments, the wireless device extends the current continuous transmission burst without performing additional LBT when the average or maximum EIRP of the allocation including the extension does not exceed the average EIRP or maximum EIRP of the transmitter when contending for the channel.

[0183] In one or more of the above embodiments, when the effective EIRP of the allocation including the extension exceeds the effective EIRP when the transmitter was contending for the channel, the wireless device performs another LBT before continuing to transmit the extension portion.

[0184] In one or more of the above embodiments, when the average EIRP or maximum EIRP of the allocation including the extension exceeds the average or maximum EIRP when the transmitter is used to contend for the channel, the wireless device performs another LBT before continuing to transmit the extension portion.

[0185] It should be understood that one or more steps of the embodiment method provided herein can be performed by corresponding units or modules. For example, a signal can be sent by a sending unit or a sending module. A signal can be received by a receiving unit or a receiving module. A signal can be processed by a processing unit or a processing module. Other steps can be performed by a detection unit / module and a determination unit / module. Each unit / module can be hardware, software or a combination thereof. For example, one or more units / modules can be an integrated circuit, such as a field programmable gate array (FPGA) or an application specific integrated circuit (ASIC).

[0186] Although the present disclosure is described with reference to illustrative embodiments, this specification is not intended to be interpreted in a limiting sense. Various modifications and combinations of the illustrative embodiments and other embodiments of the present disclosure will be apparent to those skilled in the art with reference to the description. Therefore, the present disclosure covers any such modifications or embodiments.

Claims

1. A communication method, characterized in that: include: detecting energy along a first beamforming direction; determining an energy detection threshold, wherein the energy detection threshold is determined according to a maximum value of an equivalent isotropic radiated power (EIRP) after a first time interval, wherein the first time interval includes at least one listen-before-talk (LBT) time interval or at least one clear channel assessment (CCA) time interval; as well as It is determined whether an unlicensed band channel is idle in at least a first receiving direction according to the energy and the energy detection threshold.

2. The method according to claim 1, characterized in that The detection energy comprises: Beam scanning is performed in one or more time slots to detect energy corresponding to a plurality of receiving directions, wherein each of the one or more time slots corresponds to a different receiving direction.

3. The method according to claim 1, characterized in that The detection energy comprises: Energy is detected in multiple beamforming directions, wherein the detection of energy in different receive directions is interleaved in the frequency domain.

4. The method according to claim 1, characterized in that: The detecting energy includes: detecting energy corresponding to multiple receiving directions in parallel.

5. The method according to any one of claims 1 to 4, characterized in that The method also includes normalizing the energy based on antenna gain of one or more receiving antennas.

6. The method according to claim 5, wherein: The antenna gain includes the dipole gain and the array gain.

7. A communication device, characterized in that: include: A detection module, configured to detect energy along a first beamforming direction; A determination module, configured to determine an energy detection threshold, wherein the energy detection threshold is determined according to a maximum value of an equivalent isotropic radiated power (EIRP) after a first time interval, wherein the first time interval includes at least one listen-before-talk LBT time interval or at least one clear channel assessment CCA time interval; The determination module is further configured to determine whether the unlicensed frequency band channel is idle in at least a first receiving direction according to the energy and the energy detection threshold.

8. The device according to claim 7, characterized in that The detection module is used to detect energy, including: The detection module is used for performing beam scanning in one or more time slots to detect energy corresponding to multiple receiving directions, wherein each of the one or more time slots corresponds to a different receiving direction.

9. The device according to claim 7, characterized in that The detection module is used to detect energy, including: The detection module is used to detect energy in multiple beamforming directions, wherein the detection of energy in different receiving directions is staggered in the frequency domain.

10. The device according to claim 7, characterized in that The detection module is used to detect energy, including: The detection module is used to detect energy corresponding to multiple receiving directions in parallel.

11. The device according to any one of claims 7 to 10, characterized in that The apparatus is further configured to normalize the energy according to antenna gain of one or more receiving antennas.

12. The device according to claim 11, characterized in that The antenna gain includes the dipole gain and the array gain.

13. A communication device, comprising: a memory including instructions; as well as One or more processors in communication with the memory, wherein the one or more processors execute the instructions to cause the apparatus to perform the method of any one of claims 1 to 6.

14. A computer readable medium having instructions stored thereon, characterized in that: When the instructions are executed, the computer is caused to perform the method according to any one of claims 1 to 6.

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