阅读说明：本技术 针对未许可频带中的大规模多输入多输出(mimo)的动态干扰抑制 (Inhibit for the dynamic disturbance of the extensive multiple-input and multiple-output (MIMO) in unlicensed band ) 是由 A·加西亚·罗德里格斯 G·杰拉奇 D·洛佩兹-佩瑞兹 L·加拉茨·焦尔达诺 A·邦凡特 于 2018-02-27 设计创作，主要内容包括：一种节点被配置为连接到大规模多输入多输出(MIMO)阵列,以在未许可频带中向多个用户设备提供空间复用信道。该节点包括处理器,处理器被配置为基于由节点执行以获取未许可频带的第一先听后说(LBT)操作的结果,向干扰抑制分配大规模MIMO阵列的一定数目的自由度。处理器还被配置为基于被分配给干扰抑制的自由度的数目来生成空间滤波器。该节点还包括收发器,收发器被配置为使用空间滤波器来执行第二LBT操作。(A kind of node is configured to connect to extensive multiple-input and multiple-output (MIMO) array, to provide spatial reuse channel to multiple user equipmenies in unlicensed band.The node includes processor, processor be configured as based on being executed from node with obtain unlicensed band the first listem-before-talk (LBT) operation as a result, distributing the freedom degree of the certain amount of extensive MIMO array to AF panel.Processor is additionally configured to generate spatial filter based on the number for the freedom degree for being assigned to AF panel.The node further includes transceiver, and transceiver is configured with spatial filter to execute the 2nd LBT operation.)

1. a kind of method, comprising:

Implementing extensive multiple-input and multiple-output (MIMO) array to provide space to multiple user equipmenies in unlicensed band At the node of multipling channel, grasped based on being executed by the node with obtaining the first listem-before-talk (LBT) of the unlicensed band Make as a result, distributing the freedom degree of the certain amount of the extensive MIMO array to AF panel；

Spatial filter is generated based on the number for the freedom degree for being assigned to AF panel；And

The 2nd LBT operation is executed using the spatial filter.

2. according to the method described in claim 1, further comprising:

The spatial filter is being applied to the letter obtained during the first LBT operation by the extensive MIMO array Number sample before, store the sample.

3. according to the method described in claim 2, including: wherein in response to institute to the freedom degree that AF panel distributes the number The result for stating the first LBT operation is that the successful and described node obtains the unlicensed band, selectively reduces quilt Distribute to the number of the freedom degree of AF panel.

4. according to the method described in claim 2, including: wherein in response to institute to the freedom degree that AF panel distributes the number State that the first LBT operation is unsuccessful and the node fails to obtain the unlicensed band, selectively increase be assigned to it is dry Disturb the number of the freedom degree of inhibition.

5. according to the method described in claim 1, further comprising:

Determine the freedom degree of initial number to AF panel based on the number in the dominant characteristics direction for covariance matrix Distribution, the covariance matrix are used for the received signal during the Quiet Time intervals of the node.

6. a kind of node, the node is configured to connect to extensive multiple-input and multiple-output (MIMO) array, unlicensed Spatial reuse channel is provided to multiple user equipmenies in frequency band, the node includes:

Processor is configured as based on the first listem-before-talk (LBT) for obtaining the unlicensed band by node execution Operation as a result, distribute the freedom degree of the certain amount of the extensive MIMO array to AF panel, and based on being assigned Spatial filter is generated to the number of the freedom degree of AF panel；And

Transceiver is configured with the spatial filter to execute the 2nd LBT operation.

7. node according to claim 6, further comprises:

Memory is configured as being applied to the spatial filter during the first LBT operation by described extensive Before the sample for the signal that MIMO array obtains, the sample is stored.

8. node according to claim 6, wherein the processor is configured to: in response to the first LBT operation The result is that the successful and described node obtains the unlicensed band, selectively reduces and is assigned to AF panel The number of freedom degree.

9. node according to claim 6, wherein the processor is configured to: not in response to the first LBT operation The successful and described node fails to obtain the unlicensed band, selectively increases the freedom degree for being assigned to AF panel The number.

10. node according to claim 6, wherein the processor is configured to: based on the master for being directed to covariance matrix The number of characteristic direction is led to determine the freedom degree of initial number to the distribution of AF panel, the covariance matrix is used in institute By the transceiver received signal during stating the Quiet Time intervals of node.

Background technique

Unlicensed band is the part of radio spectrum, they do not require the use of license, and therefore can be by meeting regulations Any equipment be used to emit or receive radiofrequency signal.Emit or receive the wireless of signal in licensed band or unlicensed band Communication equipment is commonly known as node, they may include being operated in unlicensed spectrum according to 802.11 standard of IEEE Wi-Fi access point.Node further includes according to long term evolution (LTE) mark such as defined by third generation partner program (3GPP) The base station that the standard of standard etc operates in licensed spectrum.It can implement to mend in unlicensed spectrum according to the base station of LTE operation Downlink (SDL) channel is filled, to provide additional bandwidth to user equipment to be used for downlink communication, these user equipmenies Also using the channel and base station communication in licensed band.Licensed band can be referred to as LTE-L frequency band, and unlicensed band can To be referred to as LTE-U frequency band.Other base stations assist access (LAA) standard to operate in unlicensed band according to license.Some bases Standing only, operation is without the support in licensed band in unlicensed band, for example, according to the new of such as MuLTEFire etc Emerging standard.

In dense network, the channel in unlicensed band can be by grasping according to different radio access technologies (RAT) The node (such as Wi-Fi access point and LTE base station) of work is reused.The communication carried out by the node operated according to different RAT It is coordinated, the interference between transmission to reduce different nodes using unobstructed channel estimation techniques.For example, listem-before-talk (LBT) rule coexists and requires each node monitoring channel (for example, " listening "), to be detected on channel before channel information Energy.If the energy level detected is lower than threshold level, channel is considered unobstructed, and node is scheduled It is freely transmitted on channel in time interval.If the energy level detected is higher than threshold level, (it indicates that channel is not logical Smooth, because another node is just in channel), then listener node is carrying out another trial to retract before obtaining channel, Until energy level drops to threshold value or less.Energy detection threshold for Wi-Fi is -62 decibels-milliwatt (dBm), and needle Energy detection threshold to LTE-U, LAA is that -72dBm and MuLTEFire is -72dBm.Wi-Fi node can also be to as follows Signal execute the decoding of Wi-Fi lead code, these signals have lower than energy detection threshold and detecting higher than -82dBm Energy level.If Wi-Fi node is successfully decoded by other energy waters of Wi-Fi node between -62dBm and -82dBm Lead code in the flat transmission carried out, then the Wi-Fi node retracts.

Detailed description of the invention

By reference to attached drawing, the disclosure can be better understood, and make its many features and advantage to this field Technical staff be apparent.Similar or identical project is indicated the use of same reference numeral in different figures.

Fig. 1 is the block diagram of wireless communication system in accordance with some embodiments.

Fig. 2 is curve graph, is used as space zero point number for different Wi-Fi configuration which illustrates in accordance with some embodiments Purpose function realized and rate.

Fig. 3 is the block diagram of the node in accordance with some embodiments for being configured to connect to extensive MIMO array.

Fig. 4 illustrates the different number of freedom in accordance with some embodiments that AF panel is used in successive time interval The dynamic allocation of degree.

Fig. 5 is the flow chart of method in accordance with some embodiments, and this method is assigned to interference suppression for dynamically modification The number of the freedom degree of the extensive MIMO array of system.

Fig. 6 is the wireless communication system of the dynamic allocation in accordance with some embodiments for executing the freedom degree for AF panel Block diagram.

Specific embodiment

The antenna for the big figure in extensive multiple-input and multiple-output (MIMO) array implemented by node provides big figure Spatial degrees of freedom, can support the spatial multiplexing communication with multiple user equipmenies.As long as example, N >=K, N number of antenna it is big Scale MIMO array can provide spatial reuse channel to each user equipment in K user equipment.Additional space is free Degree can be assigned to AF panel, be coexisted with improving with other transmitters (such as interfering Wi-Fi nodes).For example, passing through At least D freedom degree is distributed to the space zero point being placed on direction in space corresponding with D interfering nodes, D single The interference of antenna interference node can be suppressed, wherein D≤N-K.The freedom degree of the big figure of extensive MIMO array is distributed A possibility that node successfully obtains unlicensed band during LBT process is increased to AF panel.However, being obtained not in node In the case where licensed band, each freedom degree for being assigned to AF panel becomes unavailable for user data wave beam forming or multiple With.The rival demand of AF panel and user data wave beam forming or multiplexing is routinely by distributing the freedom degree of fixed number It is balanced to AF panel.However, the static assignment of freedom degree does not result in the optimum performance of node, because actual needs is suppressed Interference volume time to time change, for example, because the numbers of interfering nodes may be due to activation, deactivation, mobility, environment item Part etc. and increase or decrease.

Implement extensive MIMO array and provides the section of spatial reuse channel with multiple user equipmenies into unlicensed band The performance of point is modified by following: previous listem-before-talk (LBT) operation of unlicensed band is obtained based on being executed by node As a result, the freedom degree of extensive MIMO array is dynamically distributed to AF panel.In some embodiments, the first number Freedom degree be assigned to AF panel, and node executes LBT operation to attempt to obtain unlicensed band.If LBT is operated Result be successful, and node obtains unlicensed band, then node, which determines to reduce, is assigned to the freedom degree of AF panel Number whether may make performance degradation.For example, the freedom degree of reduction number can be used to generate modified space in node Filter is to be used for AF panel.Modified spatial filter is then applied to the letter obtained during previous LBT operation Number the sample stored, whether will be successful when reducing the freedom degree of number with the result of determination previous LBT operation. If it is, then being operated for subsequent LBT and in data transmission or reception period, being assigned to the freedom degree of AF panel Number be reduced.If it is not, then the number of freedom degree is maintained at current number.If the result of previous LBT operation is not Success, and node cannot obtain unlicensed band, then and node determines the number for increasing the freedom degree for being assigned to AF panel Whether performance is possibly improved.For example, the freedom degree of increase number can be used to generate modified spatial filter in node.Through The spatial filter of modification is then applied to the stored sample of the signal obtained during previous LBT operation, to determine first Whether the result of preceding LBT operation will succeed when increasing the freedom degree of number.If it is, then being operated for subsequent LBT And it is increased in data transmission or reception period, the number for being assigned to the freedom degree of AF panel.If it is not, then freely The number of degree is maintained at current number.

Fig. 1 is the block diagram of wireless communication system 100 in accordance with some embodiments.Wireless communication system 100 includes being connected to The node 105 of extensive MIMO array 110, extensive MIMO array 110 include (N number of) antenna element of certain amount, these The multiplexing of the wave beam forming for the down link signal that antenna element is used to be launched and the uplink signal being received.Schemed In the embodiment shown, extensive MIMO array 110 is implemented as being depicted as the two-dimentional battle array of the antenna element of small cube in Fig. 1 Column.However, some embodiments of extensive MIMO array 110 are carried out using other antenna configurations, the line including antenna element Property array, cylindrical array of antenna element, etc..As discussed herein, node 105 is generated for by MIMO gusts extensive The down link signal of the transmission of column 110, and handle by the extensive 110 received uplink signal of institute of MIMO array.

Node 105 and extensive MIMO array 110 serve multiple user equipmenies in overlay area or cell 115 111,112,113.User equipment 111,112,113 is collectively referred to herein as " user equipment 111-113 ".Extensive MIMO array The number (N) of antenna element in 110 is most greater than the user equipment serviced by node 105 and extensive MIMO array 110 Big figure (K_MAX).For example, the user equipment serviced by extensive MIMO array 110 in the embodiment illustrated in fig. 1 The number (K) of 111-113 is three.Extensive MIMO array 110 implements N=64 antenna element to service K=3 user equipment 111-113.Therefore, in this embodiment, N > > K.However, the embodiment of extensive MIMO array 110 is not limited to service three N=64 antenna element of a user equipment.Some embodiments of extensive MIMO array 110 implement more or fewer antennas Element services more or fewer user equipmenies.For example, hundreds of or thousands of antenna elements can be implemented in extensive MIMO array Part services tens of or hundreds of user equipmenies.

Some embodiments of node 105 and extensive MIMO array 110 are in unlicensed band to user equipment 111-113 It provides and is wirelessly connected.Unlicensed band is the part of radio spectrum, they do not require the use of license, and therefore can be by any Equipment is used to emit or receive radiofrequency signal.For example, unlicensed national information infrastructure (UNII) by include 5.15GHz extremely The part of the radio-frequency spectrum of frequency band in 5.825GHz range is formed.For another example industry, science and medical (ISM) radio Frequency band is the part of radio-frequency spectrum, they are internationally retained for unlicensed communication.Other than other frequency bands, ISM radio bands further include the frequency band of the centre frequency with 2.4GHz and the bandwidth of 100MHz, the center with 5.8GHz The frequency band of the bandwidth of the frequency band and centre frequency and 250MHz with 24.125GHz of frequency and the bandwidth of 150MHz.Do not permitted Can frequency band can be contrasted with licensed band, licensed band is granted to specific ISP, and is only used for by this The wireless communication of ISP or license-holder's authorization.

Node 105 and extensive MIMO array 110 are required and in unlicensed band according to identical or different radio The other equipment of access technology operation coexist.Some embodiments of node 105 and extensive MIMO array 110 are according to LTE standard Operation, and be configured as coexisting with other equipment, such as operated in the small cell 130 serviced by Wi-Fi node 120 Wi-Fi node 120,125.Node 105 can be enhanced by following to be coexisted with Wi-Fi node 120,125: utilizing big rule Space 0. 135,140 is placed on corresponding with Wi-Fi node 120,125 by the subset of the freedom degree of mould MIMO array 110 On direction in space.Node 105 supports space channel using another (mutual exclusion) subset of the freedom degree of extensive MIMO array 110 145,150,155, they are used for wave beam forming or multiplexing in direction in space corresponding with user equipment 111-113. Space 0. 135,140 and space channel 145,150,155 are indicated that the spatial filter is in node 105 by spatial filter Based on the channel state information from Wi-Fi node 120,125, the channel state information from user equipment 111,112,113, And be assigned to support space 0. 135,140 subset in freedom degree number and be generated.Therefore, node 105 It supports the communication in the first subspace of space channel 145,150,155, and generates in the space with the first Orthogonal Subspaces Space 0. 135,140 in second subspace of channel.

Node 105 is configured to dynamically change the number for being assigned to the freedom degree of space zero point, unlicensed to support It AF panel in frequency band and coexists.Some embodiments of node 105 are configured as being based on being executed by node 105 not permitted to obtain Can frequency band previous listem-before-talk (LBT) operation as a result, by the freedom degree of the certain amount of extensive MIMO array 110 point Dispensing AF panel.For example, the freedom degree that node 105 can distribute minimal amount is used for AF panel to guarantee successful LBT Operation allows node 105 to obtain unlicensed band, or the prediction possibility at least by success LBT operation is increased to threshold value More than.It is optimal for distributing the freedom degree of minimal amount necessary to operating for success LBT, because (1) node 105 can obtain Take unlicensed band, and (2) node 105 can by increase the number for the freedom degree that be assigned to wave beam forming or multiplexing come Realize bigger beam forming gain.Therefore node 105 can be moved based on the number for the freedom degree for being assigned to AF panel Spatial filter is generated to state, and use space filter operates to execute subsequent LBT.

Fig. 2 is curve graph 200, is used as space zero for different Wi-Fi configuration which illustrates in accordance with some embodiments Points purpose function realized and rate.The longitudinal axis is indicated with every sector (or cell) of megabits per second (Mbps) and fast Rate, and the number of horizontal axis instruction space zero point.Curve graph 200 indicates that for such as lower node and rate, the node use packet The extensive MIMO array of N=64 root antenna is included to service K=8 user equipment.The instruction of solid line 205 is for including every sector one The configuration of a Wi-Fi cluster and rate, dotted line 210 instruction for include every two Wi-Fi clusters in sector configuration and it is fast Rate, and lineae trapezoidea 215 indicates for the configuration for including every four Wi-Fi clusters in sector and rate.

Every kind configuration in rate 205,210,215 with space zero point number increase and increase, until and rate 205,210,215 reach peak value.Wi-Fi cluster greater number of for every sector, peak value appear in greater number of space zero At point, since it is desired that greater number of freedom degree is to inhibit the interference from greater number of Wi-Fi cluster.The zero point in space When number is lower than the value with the peak value of rate is generated, node is less likely to obtain unlicensed band, because of the freedom of insufficient number Degree is assigned to AF panel, and is operated and be less likely successfully by the LBT that node executes.In space, the number of zero point, which is higher than, produces When the value of raw and rate peak value, is operated by the LBT that node executes and a possibility that success is reached steady, but can be used for wave beam The number of figuration or the freedom degree of multiplexing is reduced, and keeps node achievable and rate degrades.

The number time to time change of the Wi-Fi cluster of every sector in actual deployment, for example, due to activating, deactivating Work, mobility, environmental condition, etc..Therefore, as illustrated in Figure 2, optimize sky required for realized as node and rate Between the number of zero point also change over time.For example, if the number of the Wi-Fi cluster of every sector is from every in first time interval The Wi-Fi cluster of sector two changes to the Wi-Fi cluster of every sector in the second time interval four, then generates the peak value with rate The number of required space zero point is changed to from for the approximation 16 with rate 210 for the approximation 25 with rate 215.Xiang Gan Therefore the dynamic allocation for disturbing the number of the freedom degree of inhibition need the number in response to interfering nodes to change in time, and maintain The optimal number of space zero point.

Fig. 3 is the block diagram of the node 300 in accordance with some embodiments for being configured to connect to extensive MIMO array.Node 300 be used to implement some embodiments of node 105 shown in Fig. 1.In scheduling frame 305, node 300 is configured as not The scheduling of communication is executed in licensed band using extensive MIMO array.In transmission frame 310, node 300 is configured as The transmission of data is executed in first subspace of space channel, while space zero is executed on the second subspace of space channel It sets.Therefore, node 300 is configured as setting the wave beam forming for being executed concurrently downlink transmission with space zero.Node 300 can also It is enough using with scheduling frame 305 and transmit frame 310 similarly the frame that operates, be executed concurrently uplink to be set with space zero and transmit Multiplexing.

In frame 315, covariance matrix of the estimation of node 300 for one or more interfering nodes.In order to estimate association side Poor matrix, node 300 interrupts during Quiet Time intervals or around transmission, and monitors during Quiet Time intervals by big Scale MIMO array received signal.Received signal be used to generate the letter for being directed to interfering nodes (such as Wi-Fi node) Channel state information.Channel state information be used to inhibit dry during subsequent silent stage and data transmission and reception stage It disturbs, for example, after Quiet Time intervals expire.In some embodiments, channel state information be used to generate for interfering The covariance matrix of node.For example, enablingIt is indicated in N number of antenna element in extensive MIMO array and is according with Number interval m at by node received signal.Node monitors received signal in the interim of M symbol, and generates The estimation of their aggregated channel covariance matrixIt is as follows:

Wherein ()^HIndicate conjugate transposition operation.Covariance matrix indicates in extensive MIMO array and its overlay area Interfering nodes between space channel.

In a block 320, space resources is assigned to downlink spatial channel and space zero point.Node determination is assigned to The number of the space zero point of the AF panel of the interfering nodes indicated in channel covariance matrices.As discussed herein, node Whether unlicensed band is successfully obtained based on previous LBT operation, to dynamically determine for subsequent LBT operation and data transmission Space zero point number.Once the number of space zero point has been determined, node generate spatial filter, indicate for pair The space channel and space zero point of downlink transmission progress wave beam forming.Spatial filter can be in LBT operational phase sum number Signal is applied to according to during the transmission stage.

In frame 325, node scheduling user is for the communication in unlicensed band.In the illustrated embodiment, Data transmission for scheduled user depends on node by the LBT operation to run succeeded to obtain unlicensed band.

In frame 330, node executes LBT operation.LBT operation is performed following signal, these signals are based on frame 320 The spatial filter of middle generation and filtered.Application space filter is referred to as " LBT of enhancing " during LBT operation.In order to Start LBT operation, node interrupts or around transmission, and monitor by extensive MIMO array received signal.Spatial filter It is applied to monitored signal, to remove the received signal on the subspace of channel for corresponding to space zero point.Therefore, In It is not included in following signal on direction in space associated with space zero point from interfering nodes received signal, these letters Number it is used for determining whether energy level detected is higher than threshold value in received signal, which indicates unlicensed band quilt Another interfering nodes occupy.If energy level detected is higher than threshold value, LBT operates unsuccessful and node and does not obtain Unlicensed band.If LBT operation is unsuccessful, node does not execute frame 335, frame 340, the operation in frame 345.If detected Energy level be lower than threshold value, then LBT operate successfully and node acquisition unlicensed band.

Node is requested for user device transmissions (at frame 335) with pilot signal transmitted, and node can be used these and lead Frequency signal is used for channel estimation.Some embodiments of node are in the space channel subspace orthogonal with the direction of most strong jamming node Upper broadcast request.For example, identified spatial filter in frame 320, which can be used, in node carrys out broadcast request.Node is in frame 340 Pilot signal is received, and estimates the channel state information for the user equipment for transmitting pilot signal using pilot signal. Spatial filter identified in frame 320 is applied to the received pilot signal of institute by some embodiments of node, thus by interfering The signal of node-node transmission space zero point represented by spatial filter inhibits.

In frame 345, node executes scheduled data transmission.Data transmit the space based on determined by a block 320 Filter and be pre-coded, with prevent data transmission cause to interfere at interfering nodes.

Fig. 4 illustrates the different numbers in accordance with some embodiments that AF panel is used in successive time interval 400,405 The dynamic allocation of purpose freedom degree.In time interval 400, extensive MIMO array 410 is by the first subset allocation of freedom degree It gives user equipment 411,412,413 (collectively referred to herein as " user equipment 411-413 "), and by the second subset of freedom degree Distribute to the inhibition to the interference from interfering nodes 415.First subset of freedom degree be used for support space channel 421, 422, the wave beam forming of the communication on 423 (collectively referred to herein as " space channel 421-423 ") or multiplexing, and freedom degree Second subset is used for the space 0. 425 for supporting to be placed on the direction in space of interfering nodes 415.

In time interval 405, the signal from additional interfering nodes 430 is detected by extensive MIMO array 410. Additional interfering nodes 430 may be activated during time interval 405, it may be possible to come during time interval 405 Mobile node or environmental condition in the range of extensive MIMO array 410 may change as follows, which Extensive MIMO array 410 is caused to detect the stronger interference signal from interfering nodes 430.As discussed herein, attached The presence of the interfering nodes 430 added can be detected based on the failure that the LBT executed by extensive MIMO array 410 is operated.It rings Ying Yu detects additional interfering nodes 430, and it is additional to support that extensive MIMO array 410 distributes greater number of freedom degree Space 0. 435 is placed on the direction in space of interfering nodes 430.Increase the number for supporting the freedom degree of AF panel A possibility that increasing successfully LBT operation, cost are to reduce the number for the freedom degree that can be used for space channel 421-423, this can It can be reduced the total throughout of space channel 421-423.

Fig. 5 is the flow chart of method 500 in accordance with some embodiments, and method 500 is assigned to dry for dynamically modification Disturb the number of the freedom degree of the extensive MIMO array of inhibition.It is shown in this method implementation node 105 shown in FIG. 1, Fig. 3 Node 300 and Fig. 4 shown in extensive MIMO array 410 some embodiments in.

At frame 505, the freedom degree of initial number is allocated for AF panel.Conservative method initially distributes big number Purpose can be used for AF panel with freedom degree, to guarantee successful LBT operation, or at least by the prediction of success LBT operation Probability increases to threshold value or more.For example, node can arbitrarily be defined by following conservative manner for AF panel from By the number (D) spent

D=[0.8N]

Wherein invariant 0.8 is obtained by the emulation in different scenes.Greedy method initially distributes peanut Freedom degree is used for AF panel.In some embodiments, the initial number for being allocated for the freedom degree of AF panel is based on association The number in the dominant characteristics direction in variance matrix determines, the covariance matrix based on from interfering nodes received signal come really It is fixed.For example, the number for the freedom degree distributed can be set to be equal to comprising from the received given percentage of interfering nodes The number of the characteristic direction of signal power.

At frame 510, node is operated based on the current distribution of the freedom degree to AF panel to execute LBT.In order to execute LBT operation, current number (D) the Lai Shengcheng spatial filter of node based on the freedom degree for being allocated for AF panel.Node Then transmission of the monitoring from one or more interfering nodes in unlicensed band in Quiet Time intervals, and application is empty Between received signal power on subspace of the filter to determine the space channel as defined in spatial filter.

At decision box 515, node is by received signal power and threshold value comparison to determine whether LBT operation succeeds. If it (is more than threshold value because of received signal power, and node is not obtained to unlicensed frequency that LBT operation, which is unsuccessful, The access of band), then node does not execute scheduled communication during the current iteration of LBT process.Then method 500 flows to judgement Frame 520.If LBT operation is that successfully (because received signal power is less than or equal to threshold value, and node is obtained to not The access of licensed band), then node executes scheduled communication.Then method 500 flows to decision box 525.

The dynamic optimization of space resources distribution can improve the success rate of LBT operation significantly, because during this stage The amount of received signal power depends on the number (D) for being allocated for the freedom degree of AF panel.For example, enabling for interference section The feature decomposition of the estimated channel covariance matrices Z (as hereinbefore defined) of point are as follows:

Z=U Λ U^H,

WhereinIt is the diagonal matrix with the characteristic value to sort in descending order, and wherein 's I-th columnIt is feature vector associated with the ith feature value in Λ.By extensive MIMO during LBT operation Spatial filter used by array is given by:

WhereinIndicate unit matrix and Σ_DIt is defined as:

Σ_D=[u₁,u₂,...,u_D]。

Therefore, spatial filter Π_DSpace zero point is placed on the direction in space that most strong jamming node is located at.These Direction in space is also referred to as the characteristic direction of estimated channel covariance matrices Z.During LBT operation in given symbol Carving perceived signal power can be expressed as:

WhereinIt is during LBT operation in symbol moment m received signal.Above-mentioned relation illustrates Be allocated for the freedom degree of AF panel number (D) play the role of in symbol moment m received signal power it is basic, For example, bigger D value reduces the item number in right-hand side adduction, and therefore reduce total signal power P [m].

If following relationship for given time interval m ∈ 1 ..., M_LBTBe satisfied, then extensive MIMO array passes Transmission of data is to user equipment:

Here, λ_LBTCommonly referred to as LBT threshold value, and it is directed to Wi-Fi equipment adopted value λ_LBT=-62dBm, and needle To LAA equipment adopted value λ_LBT=-72dBm.In data transfer phase, extensive MIMO array stores information in memory, packet It includes: (1) indicating whether successful variable and (2) are before application space filters for LBT operation, it is received during LBT operation Signal y [m].

At decision box 520, node determines whether the number for increasing the freedom degree for being assigned to AF panel is predicted to be Improve the success rate of one or more subsequent LBT operations.In some embodiments, node is predicted to increase freedom degree by following Number whether will improve success rate: will be applied to formerly based on the freedom degree spatial filter generated for having modified number Received signal y [m] during preceding LBT operation.For example, node can execute the sequence of operation below:

1) it definesOr generally,It can be used.

2) it is based onCalculate modified spatial filter

3) by by modified spatial filterSignal y [m] is applied to calculate perceived interference P [m].This Operation can be by using in one or more previously LBT operation (for example, the LBT executed during previous time window is operated) phases Between received signal and be performed.

If the interference P [m] perceived is lower than threshold value is adjusted, then node determines channel when increasing the freedom degree of number Covariance has been estimated correctly, but the number for being allocated for the freedom degree of AF panel is insufficient.Method 500 because This flows to frame 530, and node increase is assigned to the number of the freedom degree of space zero point, for example, node passes through settingTo increase D.Otherwise, node does not increase the value of D, and method 500 flows to frame 510.In some embodiments, decision box 520 negative decision can indicate that some interfering nodes have moved, and for the current of the channel covariancc of interfering nodes Estimate the propagation channel without capturing new interfering nodes.In this case, D is simply increased to be not enough to inhibit newly to interfere.

At decision box 525, node determines whether the number for reducing the freedom degree for being allocated for AF panel can be tieed up Hold the success rate of LBT operation.In some embodiments, node predicts whether the number for reducing freedom degree will be tieed up by following It holds success rate: the freedom degree spatial filter generated based on modified number is applied to during previous LBT operation Received signal y [m].For example, node can execute the sequence of operation below:

1) it definesWherein D_oldIt is used for used by AF panel freely during being indicated in previous LBT operation The number of degree.Generally,It can be used.

2) it is based onCalculate modified spatial filter

3) by by preliminary filter updateSignal y [m] is applied to calculate perceived interference P [m].This behaviour Making can be by using during one or more previously LBT operation (for example, the LBT executed during previous time window is operated) Received signal and be performed.

If lower than threshold value is adjusted, then node determination is divided the interference P [m] perceived when reducing the freedom degree of number The number for being used in the freedom degree of AF panel can be reduced, the success rate without negatively affecting LBT operation.In frame At 535, therefore node is arrangedOtherwise, node does not modify the number of the freedom degree for AF panel, and method 500 flow to frame 510.

In some embodiments, multiple instantiations of method 500 can be used differentValue is concomitantly performed.Node Then it can choose maintenance or improve the minimum of the success rate of subsequent LBT operationValue, so that the freedom degree of optimal number is divided It is used in AF panel.

Fig. 6 is the wireless communication system of the dynamic allocation in accordance with some embodiments for executing the freedom degree for AF panel 600 block diagram.Wireless communication system 600 includes the node 605 for being connected to extensive MIMO array 610, to be used for use space Channel 625,630 provides wireless connection to user equipment 615,620.Space 0. 635 can also be placed by doing by node 605 It disturbs on direction in space indicated by the position of node 640.

Node 605 includes transceiver 645, the signal for transmitting and receiving of transceiver 645, such as in node 605 and big rule The signal exchanged between mould MIMO array 610.Transceiver 645 may be implemented as single integrated circuit (for example, using single ASIC or FPGA) or be embodied as system on chip (SOC) comprising for implementing the disparate modules of the function of transceiver 645.Section Point 605 further includes processor 650 and memory 655.Processor 650 can be used to carry out the instruction stored in memory 655, And it stores information in memory 655, such as result of performed instruction.Transceiver 645, processor 650 and storage Therefore device 655 can be configured as some embodiments of node 300 shown in implementing Fig. 3.Transceiver 645,650 and of processor Memory 655 can be additionally configured to execute some embodiments of method 500 shown in Fig. 5.

In some embodiments, some aspects of technique described above can be by one of the processing system of execution software Or multiple processors are implemented.Software can including being stored in or being otherwise visibly embodied in non-transient computer Read one or more set of the executable instruction on storage medium.Software may include instruction and certain data, by one When a or multiple processors execute, manipulation one or more processors execute the one or more aspects of technique described above. Non-transient computer-readable storage media may include, for example, disk or optical disc memory apparatus, solid storage device (such as dodge Deposit), cache, random access storage device (RAM) or other non-volatile memory devices or multiple equipment, etc..It is non-transient The executable instruction stored on computer readable storage medium can be with source code format, assembler language code format, target Code format or other instruction formats being interpreted by one or more processors or otherwise can be performed.

Computer readable storage medium may include during use by the addressable any storage medium of computer system Or the combination of storage medium, to provide instruction and/or data to computer system.Such storage medium may include, but not Be limited to, optical medium (for example, compact-disc (CD), digital versatile disc (DVD), Blu-ray disc), magnetic medium (for example, floppy disk, tape, Or magnetic hard drives), volatile memory (for example, random access storage device (RAM) or cache), non-volatile memories Device (for example, read-only memory (ROM) or flash memory) or the storage medium for being based on MEMS (MEMS).It is computer-readable Storage medium can be embedded into computing system (for example, system RAM or ROM), be fixedly attached to computing system (for example, Magnetic hard drives), be removedly attached to computing system (for example, CD or be based on universal serial bus (USB) sudden strain of a muscle Deposit) or via cable network or wireless network (for example, network-accessible storage (NAS)) it is coupled to computer system.

It is noted that not all activity or element described in generality description above requires, specific activities or set It is standby it is a part of can not need, and in addition to described other than those, one or more other activities can be performed, Or one or more other elements can be included.Further, the sequence that activity is listed is not necessarily their quilts The sequence of execution.In addition, concept is described by reference to specific embodiment.However, those skilled in the art understand, no It is detached from the scope of the present disclosure described in claim as follows, various modifications and change can be made.Therefore, specification and Attached drawing will be treated in the illustrative sense rather than a restrictive sense, and all such modifications are intended to be included in the disclosure In the range of.

Benefit, other advantages and solution to the problem are being described above about specific embodiment.However, beneficial Place, advantage, solution to the problem and any benefit, advantage or solution can be made to occur or become more significant Any (multiple) features will not be interpreted the key of any or all claim, required or necessary feature.This Outside, particular embodiments disclosed above are merely illustrative, because disclosed theme can be by different but equivalent modes It is modified and is practiced, these modes are apparent to the those skilled in the art instructed herein are benefited from.In addition to right below Except described in it is required that, there is no limit the details being intended to for construction or design shown herein.It is therefore evident that Particular embodiments disclosed above can be altered or modified, and all such modifications are considered in disclosed master In the range of topic.Therefore, protection sought herein is elucidated in claim below.