Method and system for null in wireless communication network

Abstract

Methods and systems for null in a wireless communication network are disclosed herein. In one embodiment, a method performed by a first wireless communication node for initiating a null transmission comprises transmitting a control message to be received by a second wireless communication node, where the control message notifies the second wireless communication node to initiate a null transmission towards a first station; and transmitting data to the first station during transmission of the null transmission from the second wireless communication node to the first station, where the data includes an identification of one or more wireless communication nodes that are permitted to transmit the null transmission, the one or more wireless communication nodes including the second wireless communication node.

Description

[0001] This application is a divisional application of the Chinese invention patent application with application number 202080082865.0 and name “Method and system for blanking in a wireless communication network”. Technical Field

[0002] The present disclosure relates generally to wireless communications, and more particularly, to methods and systems for inter-cell interference nulling in wireless communication networks. Background Art

[0003] With the rapid growth of user data, the demand for spectrum is increasing. Previous solutions to address existing and emerging user data services require increasing data rates by widening channels or dense base station (BS) deployment. For example, channel bandwidth has increased from 200kHz in 2G Global System for Mobile Communications (GSM) to 5MHz in 3G Wideband Code Division Multiple Access (WCDMA), and from 20MHz in 4G Long Term Evolution (LTE) to 100MHz in Advanced LTE Pro. However, conventional sub-6GHz spectrum is almost fully allocated, and licensing is expensive for system operators. In addition, the cost and time required to obtain backhaul connectivity and site selection permits in millions of local jurisdictions limit further densification of the network. In addition, even complete reuse of frequency resources between adjacent cells can lead to high levels of inter-cell interference, which in turn severely limits the available communication speeds for some users, especially at the cell edge.

[0004] Regarding wireless LANs, the same challenges exist as for cellular wireless networks. For example, dense deployment of access points (APs) in many stores, apartments, or shopping malls can cause overlapping basic service sets (BSSs), which degrades the performance of each network. Existing solutions address the problem of overlapping BSSs or inter-cell interference in wireless LANs by using different orthogonal channels on each AP. However, this solution is impractical when the number of APs exceeds the number of available orthogonal channels.

[0005] Reusing frequency resources across neighboring cells can increase the capacity of wireless network designs. However, there is a need for inter-cell interference management systems and methods. In particular, there is a need for systems and methods for inter-cell interference nulling between neighboring cells. Summary of the invention

[0006] The exemplary embodiments disclosed herein are intended to solve problems related to one or more problems existing in the prior art, as well as to provide additional features, which will become apparent when the following detailed description is made in conjunction with the accompanying drawings. According to various embodiments, exemplary systems, methods, devices, and computer program products are disclosed herein. However, it should be understood that these embodiments are presented by way of example and not limitation, and it will be apparent to those of ordinary skill in the art who have read this disclosure that various modifications may be made to the disclosed embodiments while remaining within the scope of this disclosure.

[0007] In one embodiment, a method for initiating a blanking transmission performed by a first wireless communication node includes: transmitting a control message to be received by a second wireless communication node, wherein the control message notifies the second wireless communication node to initiate a blanking transmission toward a first station; and transmitting data to the first station during the transmission of the blanking transmission from the second wireless communication node to the first station.

[0008] In another embodiment, a method for providing a blanking transmission performed by a first wireless communication node includes: receiving a control message from a second wireless communication node, wherein the control message notifies the first wireless communication node to initiate a blanking transmission toward a first site; and transmitting data to the second site during the blanking transmission from the first wireless communication node to the first site.

[0009] In another embodiment, a device for initiating a blanking transmission includes: a transceiver, the transceiver being configured to: transmit a control message to be received by a wireless communication node, wherein the control message notifies the wireless communication node to initiate a blanking transmission toward a first station; and transmit data to the first station during the transmission of the blanking transmission from the wireless communication node to the first station.

[0010] In another embodiment, an apparatus for initiating a blanking transmission includes: a receiver configured to receive a control message from a wireless communication node; at least one processor configured to control an antenna to direct the blanking transmission toward a first station based on the received control message; and a transmitter configured to transmit data to a second station while transmitting the blanking transmission to the first station.

[0011] In further embodiments, the present invention provides a non-transitory computer-readable storage medium storing computer-executable instructions that, when executed, perform any of the methods disclosed herein.

[0012] In yet another embodiment, a wireless communication node includes a memory storing computer executable instructions that, when executed, perform any of the methods disclosed herein; and at least one processor coupled to the memory and configured to execute the computer executable instructions. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Various exemplary embodiments of the present disclosure are described in detail below with reference to the accompanying drawings. The accompanying drawings are provided for illustrative purposes only and only describe exemplary embodiments of the present disclosure to facilitate the reader's understanding of the present disclosure. Therefore, the accompanying drawings should not be considered as limiting the breadth, scope or applicability of the present disclosure. It should be noted that for clarity and ease of description, these drawings are not necessarily drawn to scale.

[0014] Figure 1 Illustrated is a block diagram of an exemplary multi-cell communication network in which the interference nulling techniques disclosed herein may be implemented according to some embodiments of the present invention.

[0015] Figure 2A A timing diagram for transmission of a control message, data transmission to a first station, and data transmission for interference nulling to a second station according to some embodiments of the present invention is illustrated.

[0016] Figure 2B A timing diagram for transmitting a control message, a channel contention window, data transmission to a first station, and data transmission for interference nulling to a second station according to another embodiment of the present invention is illustrated.

[0017] Figure 2C A timing diagram for transmission of a control message, a response message, a data transmission to a first station, and a data transmission for interference nulling to a second station according to various embodiments of the present invention is illustrated.

[0018] Figure 3A A block diagram of an exemplary multi-cell communication network in which a station transmits or relays control messages to a wireless communication node is illustrated according to some embodiments of the present invention.

[0019] Figure 3B A timing diagram for transmitting a first control message, a second control message, data transmission to a first station, and data transmission for interference nulling to a second station according to another embodiment of the present invention is illustrated.

[0020] Figure 4 A timing diagram for data transmission to a first station and delayed data transmission with interference nulling to a second station according to various embodiments of the invention is illustrated.

[0021] Figure 5AA block diagram of an exemplary multi-cell communication network in which interference nulling techniques are implemented with a first station receiving a control message from a first communication node and transmitting a response message prior to receiving a data transmission is illustrated according to some embodiments of the present invention.

[0022] Figure 5B A timing diagram for transmitting a first control message, a second response message, a data transmission to a first station, and a data transmission with nulling to a second station according to other embodiments of the present invention is illustrated.

[0023] Figure 6 The diagram illustrates a timing diagram for transmitting a first control message, a first channel contention window, a second channel contention window with a suspended backoff process, a third channel contention window with a suspended backoff process, data transmission to a first station, and data transmission with interference nulling to a second station according to other embodiments of the present invention.

[0024] Figure 7 A block diagram of a wireless communication node configured to perform the methods disclosed herein according to various embodiments of the invention is illustrated. DETAILED DESCRIPTION

[0025] Various exemplary embodiments of the present disclosure are described below with reference to the accompanying drawings to enable those of ordinary skill in the art to make and use the present disclosure. It is obvious to those of ordinary skill in the art that, after reading the present disclosure, various changes or modifications may be made to the examples described herein without departing from the scope of the present disclosure. Therefore, the present disclosure is not limited to the exemplary embodiments and applications described and illustrated herein. In addition, the specific order and / or hierarchy of steps in the methods disclosed herein are merely exemplary methods. Based on design preferences, the specific order or hierarchy of steps of the disclosed methods or processes may be rearranged while remaining within the scope of the present disclosure. Therefore, it will be understood by those of ordinary skill in the art that the methods and techniques disclosed herein present various steps or actions in an example order, and the present disclosure is not limited to the specific order or hierarchy presented unless otherwise expressly stated.

[0026] As discussed herein, a "wireless communication node" may include or be implemented as a next generation node B (gNB), an E-UTRAN node B (eNB), a transmission reception point (TRP), an access point (AP), a donor node (DN), a relay node, a core network (CN) node, a RAN node, a master node, a secondary node, a distributed unit (DU), a centralized unit (CU), etc., which is consistent with the common understanding of these terms in the art. In addition, as discussed herein, a "wireless communication device" may include or be implemented as a station (STA), a mobile terminal (MT), a mobile station (MS), etc., which is consistent with the common understanding of these terms in the art. In the description of the following exemplary embodiments, a "wireless communication node" is referred to as an "AP", and a "wireless communication device" is referred to as a "STA". However, it should be understood that the scope of the present disclosure is not limited to these exemplary embodiments.

[0027] Figure 1 FIG. 1 illustrates an exemplary communication network 100 according to some embodiments of the present invention, in which the inter-cell interference nulling techniques disclosed herein may be implemented. Figure 1 As shown in FIG. 1 , an exemplary multi-cell communication network 100 includes a master AP (MAP) 101, a neighbor AP (NAP) 104, and a plurality of STAs (e.g., a first STA 102 and a second STA 103), which are communicatively coupled to the MAP 101 and the NAP 104 via respective RF links 108, 109, 110, and 111. In some embodiments, the RF links 108, 109, 110, and 111 are unlicensed links. In various embodiments, the RF links 108, 109, 110, and 111 operate in a millimeter wave radio frequency band, such as a 60 GHz unlicensed band. Figure 1 Also shown is a wireless cell coverage area 105 of the MAP 101 and a wireless cell coverage area 106 of the NAP 104. Figure 1 As shown in , in some embodiments, wireless cells 105 and 106 may have overlapping coverage areas 107. In other embodiments, STA 102 and STA 103 may be co-located in the overlapping coverage area 107, near the cell edges of wireless cells 105 and 106. Thus, according to some embodiments, the present disclosure describes systems and methods for providing inter-cell interference nulling for stations located in the overlapping coverage area 107.

[0028] According to various embodiments, the MAP 101 and the NAP 104 may each be equipped with multiple antennas (e.g., antenna arrays) configured to provide multiple-input multiple-output (MIMO) links with multiple STAs 102 and 103. In an alternative embodiment, the MAP 101 and the NAP 104 may each be equipped with a phased array antenna capable of forming one or more radio beams that can be electronically steered. In addition, the MAP 101 and the NAP 104 are configured to use the same channel resources (such as frequency and time) to perform transmissions to the multiple STAs 102 and 103. Although in Figure 1 Only two APs 101 and 104, and only two STAs 102 and 103 are shown, but it should be understood that according to various embodiments of the present invention, additional APs and additional STAs may exist in the wireless network to implement the inter-cell interference nulling technology described herein.

[0029] Similar to MAP 101 and NAP 104, STA 102 and STA 103 may also each include multiple antennas or phased antenna arrays. In an alternative embodiment, STA 102 and STA 103 may each be equipped with a single antenna. Figure 1 In the example shown in FIG. 1 , STA 102 and STA 103 may be associated with MAP 101 and NAP 104. In one embodiment, STA 102 and STA 103 may be associated with MAP 101 and NAP 104 via a basic service set (BSS).

[0030] like Figure 1As shown in FIG. 1 , MAP 101 is configured to generate a data transmission beam 108 and transmit the data transmission beam to a first STA 102, and NAP 104 is configured to generate a data transmission beam 109 and transmit the data transmission beam to a second STA 103. MAP 101 is also configured to generate and transmit an interference nulling beam 111, which is intended to null / minimize the transmission power toward the second STA 103, and NAP 104 is also configured to generate and transmit an interference nulling beam 110, which is intended to null / minimize the transmission power toward the first STA 102. According to various embodiments, MAP 101 and NAP 104 may form interference nulling beams 109 and 110 using any precoding scheme. For example, MAP 101 and NAP 104 may null interference signals toward STA 102 and STA 103 using a linear precoding technique, such as a zero-forcing (ZF) beamforming method. Such precoding enables MAP 101 and NAP 104 to create antenna patterns that favor wave propagation along desired spatial directions while attenuating (nulling) propagation along undesired directions.

[0031] In some embodiments, MAP 101 and NAP 104 rely on estimated channel state information (CSI) that describes the channel characteristics of the RF link between the transmitter and the receiver to form data transmission beams 108 and 109 and interference nulling beams 110 and 111 accordingly. Figure 1 As shown in FIG. 1 , according to some embodiments, the MAP 101 may simultaneously transmit a data transmission beam 108 to the first STA 102 and an interference nulling beam 111 to the second STA 103. Similarly, according to some embodiments, the NAP 104 may simultaneously transmit a data transmission beam 109 to the second STA 103 and an interference nulling beam 110 to the first STA 102. In addition, the channel state information (CSI) may indicate the propagation state of the communication link from the transmitter to the receiver, such as the combined effects of scattering, fading, and power attenuation with distance.

[0032] Typically, the receiver can estimate the CSI by a predetermined signal (such as a reference signal, a training signal, or a pilot signal) in a received radio frame. Therefore, CSI makes it possible to adjust the transmission according to the channel conditions, so that higher network throughput and spectrum efficiency can be achieved in MIMO systems. In some embodiments, CSI can be utilized to calculate the precoding vector / matrix for beamforming in order to minimize the signal energy at the target receiver. According to some embodiments, CSI can also be used to determine whether interference to another target receiver in an adjacent network can be eliminated. In some embodiments, CSI can be represented in the form of a channel impulse response in the time domain or a channel frequency response in the frequency domain.

[0033] Figure 2A A timing diagram for transmitting a wireless control message 201 from a master AP (e.g., MAP 101) to a neighboring AP (e.g., NAP 104) is illustrated, wherein the control message notifies the neighboring AP that a blanking transmission 204 is allowed from the neighboring AP to a target station (e.g., first STA 102). In some embodiments, the control message 201 is transmitted in a radio frame. In alternative embodiments, for a given wireless network, system, or protocol, the control message 201 may be transmitted in any suitable data format (e.g., subframe, resource block (RB), etc.) having any suitable length / size. Figure 2A As shown in , in some embodiments, after completing the transmission of the control message 201, after a predetermined amount of time 202, the master AP starts data transmission 203 to the target site. In some embodiments, the radio frame carrying the wireless control message 201 may be a notification frame or a trigger frame. In some embodiments, the radio frame carrying the wireless control message 201 may be a null packet including only the leading portion of the data packet. In some embodiments, the predetermined amount of time 202 may be a SIFS (e.g., 16 microseconds).

[0034] In some embodiments, the wireless control message 201 may include an identification of one or more neighboring APs (e.g., NAP 104). For example, the wireless control message 201 may include a single ID, a group ID, a media access control (MAC) address, a pairing ID of one or more neighboring APs, two or more single IDs, multiple group IDs, multiple MAC addresses, or a pairing ID of two or more neighboring APs that are permitted to transmit a blanking transmission 204 to one or more target STAs. After receiving the control message, the one or more neighboring APs are configured to transmit a data transmission to a corresponding STA (e.g., the second STA 103) that is different from the target STA (e.g., the first STA 102), wherein the target STA is blanked. In other words, each neighboring AP will transmit data to the corresponding intended STA while transmitting a blanking transmission (i.e., an interference blanking beam) to the corresponding target STA. The effect of the blanking transmission is to eliminate the effect of any interference that may reach the target STA from the intended data transmission to the intended STA. In some embodiments, after a predetermined time period after receiving the control message 201, one or more neighboring APs will begin transmitting the data transmission 204 with the nulling operation, so that the data transmission 204 with the nulling operation will begin substantially simultaneously with the master AP starting its data transmission 203 to the target STA.

[0035] refer to Figure 2B In some embodiments, the master AP will transmit a control message (e.g., a radio frame) 211 and, after a predetermined time period 212, transmit a data transmission 213 to a target STA (e.g., the first STA 102). This is similar to the above description of Figure 2A Embodiment described. However, in this embodiment, after the neighboring AP receives the control message 211 from the master AP, the neighboring AP may initiate a channel contention protocol 214. The channel contention protocol 214 may be any mechanism for sharing a given wireless channel between multiple APs that desire to utilize the wireless channel simultaneously. For example, the channel contention protocol 214 may be based on an enhanced distributed channel access (EDCA) or distributed channel function (DCF) mechanism. According to various other embodiments, when an enhanced distributed channel access (EDCA) or distributed channel function (DCF) mechanism is used, a neighboring AP may be allowed to access a shared wireless channel with a higher priority than a station associated with it.

[0036] Figure 2C A timing diagram for transmitting a control message, a response message, data transmission to a first station, and data transmission for interference nulling to a second station according to other embodiments of the present invention is illustrated. Figure 2C Similar to Figure 2A, however, in response to receiving the control message 221, the neighboring AP will transmit a response message 223. According to various embodiments, the response message 223 may be an acknowledgement (ACK) frame, a clear to send (CTS) control frame, or a null frame. In some embodiments, the master AP may start a data transmission 222 after a predetermined time period after receiving the response message 223 from the neighboring AP. Similarly, after a predetermined time period after completing the transmission of the response message 223, the neighboring AP will initiate the transmission of a data transmission with a nulling operation 224. In some embodiments, after completing the transmission of the response message 223, both the master AP and the neighboring AP will start their respective transmissions 222 and 224 substantially simultaneously.

[0037] In addition, before transmitting the data transmission with the blanking operation 224, the response message 223 may be transmitted by the neighboring AP to occupy the wireless channel. In this case, a channel contention process with other neighboring APs may not be necessary because, after detecting the response message transmitted by the first neighboring AP, the other neighboring APs may be preconfigured to maintain their respective channel contention processes for a predetermined time period. In some embodiments, the response message 223 may include information related to the duration that the shared wireless channel may be occupied by the neighboring AP when performing the data transmission with the blanking operation 224. Therefore, the other neighboring APs may maintain their respective channel contention processes for the indicated duration to perform the data transmission with the blanking operation 224. As discussed above, the data transmission with the blanking operation 224 includes a data transmission to the intended STA (e.g., the second STA 103) while transmitting an interference cancellation "blank transmission" to the target STA (e.g., the first STA 102).

[0038] In another embodiment, information about the duration or length of the data transmission from the master AP or the neighboring AP may be included in the wireless control message 221 and / or the response message 223. In the case where the duration of the data transmission from the master AP and the neighboring AP is uneven, the maximum duration of the data transmission may be used to set the length field of the data transmission frame. In some embodiments, for example, the maximum duration may be set in the L-SIG field or the duration field of the MAC header. Thus, all involved APs may add additional transmission time "padding" to align their data transmission frames with the maximum duration of the data transmission frame to be allocated to the AP.

[0039] Figure 3A A block diagram of an exemplary multi-cell communication network in which a station transmits or relays control messages to a wireless communication node is illustrated according to some embodiments of the present invention. Figure 3AAs shown in FIG, a master AP (MAP) 301 sends a wireless control message to some associated stations (STA) 303 via an RF link 302. After receiving the wireless control message from MAP 301, STA 303 can relay the original control message or transmit an updated wireless control message to a neighboring AP (NAP) 304 via an RF link 305, notifying NAP 304 that it can perform a blanking transmission. In some embodiments, STA 303 can directly forward or relay a first wireless frame containing a control message received from MAP 301 to NAP 304. In an alternative embodiment, MAP 301 transmits a first wireless frame containing a first control message to STA 303. The first control message instructs STA 303 to transmit a second wireless frame containing a second control message to NAP 304. The second control message instructs NAP 304 to allow NAP 304 to perform a blanking transmission. After receiving the first control message or the second control message, NAP 304 can perform a blanking transmission according to, for example, the above description. FIG. 2A to FIG. 2C Any of the methods discussed, NUL performs a data transfer with a NUL operation.

[0040] Figure 3B A timing diagram of a method of transmitting a wireless control message 306 from a master AP (MAP) to an associated station (STA), which in turn transmits an updated wireless control message 307 informing a neighboring AP (NAP) that blanking transmission is permitted. Figure 3B As shown in , MAP transmits a wireless control message 306 to the STA within a first wireless frame. In some embodiments, the STA may transmit an updated wireless control message 307 in a second wireless frame after a short inter-message space (SIFS) interval (e.g., 16us) after receiving the wireless control message 306. In another embodiment, the updated wireless control message 307 may be an acknowledgment (ACK) message. In some embodiments, the STA may transmit the updated wireless control message 307 after executing a channel contention protocol, as discussed above. In addition, after a predetermined time after completing the sending of the updated wireless control message 307 from the associated station, both MAP and NAP may initiate data transmission 308 and blank transmission 309, respectively. In an alternative embodiment, the associated STA may simply relay the first wireless frame containing the first control message to the NAP, as discussed above. Upon receiving the first control message or the second control message, the NAP 304 may initiate a data transmission 308 and a blank transmission 309, for example, according to the above description. FIG. 2A to FIG. 2C Any of the methods discussed, NUL performs a data transfer with a NUL operation.

[0041] Figure 4A timing diagram of a method of transmitting a data transmission message 401 from a master AP according to various embodiments of the present invention is illustrated, wherein the data transmission message 401 has a control message embedded in the data transmission message 401 indicating that a blanking transmission is allowed. In some embodiments, the data transmission message 401 may include the identification of one or more neighboring APs that are permitted to transmit a data transmission with a blanking operation 402. For example, the data transmission message 401 may include a single APID, a group ID of neighboring APs, a MAC address, or a pair of IDs of neighboring APs that are permitted to transmit the blanking transmission 402 to corresponding sites along with their corresponding data transmissions. In other embodiments, information indicating the blanking transmission, the identification of the neighboring APs, and any other additional control message / signaling may be included in the preamble or PHY header of the data transmission message 401. In some embodiments, as Figure 4 As shown, after a predetermined time period 403 after receiving the data transmission message 401, the neighboring AP may blank and start the data transmission with the blanking operation 402. In another embodiment, after receiving the control message, the neighboring AP may blank and start the data transmission with the blanking operation 402 according to the above FIG. 2A to FIG. 2C Any of the methods discussed to perform the operation.

[0042] Figure 5A A block diagram of an exemplary multi-cell communication network according to some embodiments of the present invention is illustrated in which interference nulling techniques are implemented using a first station receiving a control message from a first communication node and transmitting a response message before receiving a data transmission. Figure 5A As shown in FIG, a master AP (MAP) 501 sends a wireless control message to a first station (STA) 505 via an RF link 504. After receiving the wireless control message from MAP 501, STA 505 may transmit a response message to MAP 501 and a neighboring AP (NAP) 509 via RF links 503 and 508, respectively. The response message indicates to NAP 509 that it is permitted to perform blanking transmission. In some embodiments, NAP 509 may estimate channel state information (CSI) based on the response message received from STA 505. In addition, NAP 509 may store the channel state information (CSI) measurement value. In addition, NAP 509 may use the stored CSI to form an interference nulling beam toward STA 505.

[0043] After receiving the response message from the STA 505, the MAP 501 and the NAP 509 may start data transmission via the RF links 502 and 506, respectively. According to various embodiments, the NAP 509 selects a second target station (STA) 507 associated with the NAP 509 to transmit data to the target station 507 based on one or more predetermined criteria. In some embodiments, the one or more predetermined criteria may be that when the NAP 509 transmits data to the second STA 507, with the null transmission toward the first STA 505, the residual signal strength toward the first STA 505 is less than or equal to a predetermined threshold value null. Alternatively, if no target station meets the residual signal strength condition within the wireless cell coverage of the NAP 509, the data transmission with the null operation from the NAP 509 is suspended.

[0044] Figure 5B The diagram illustrates a timing diagram for transmitting a wireless control message 510 from a master AP (MAP) to a target station, which in turn transmits a response message 511, notifying both the MAP and the neighboring AP (NAP) that blank transmission is allowed, according to some embodiments. In some embodiments, the wireless control message 510 may be embedded in a wireless frame. In some embodiments, the response message 511 may be included in a wireless frame referred to as a "response frame 511." In some embodiments, the response frame 511 may be an empty frame. In other embodiments, the response frame 511 may be embedded in a PHY header of a wireless frame transmitted from the target station. In addition, the response message included in the response frame 511 may be included in a SIG field or a training signal of the wireless frame. As shown in FIG. Figure 5B As shown in FIG. 5 , after a predetermined time interval after receiving the response message 511, the MAP and the NAP may start data transmission 512 and data transmission with a null operation 513, respectively. In other embodiments, after receiving the response message 511, the NAP may start data transmission 512 and data transmission with a null operation 513, respectively. FIG. 2A to FIG. 2C Any of the methods discussed to perform the operation.

[0045] In some embodiments, there may be several neighboring APs causing inter-cell interference. Figure 6A timing diagram of a method for limiting blanking transmissions in the presence of several interfering neighboring APs according to various embodiments of the present invention is illustrated. For example, according to a given protocol, a MAP may transmit a wireless control message 601 in a preamble or PHY header of a radio frame, the wireless control message including information indicating that blanking transmissions are allowed or expected, IDs of one or more NAPs, and other additional control messages / signaling. In addition, the MAP may transmit a data transmission message 602 after a predetermined amount of time. In addition, a carrier sense multiple access with collision avoidance (CSMA / CA) mechanism may be implemented between NAPs that detect or receive a blanking transmission 604 from another neighboring AP. For example, one of the NAPs may end its channel contention backoff window 603 earlier than the other NAPs, and may blank start a data transmission with a blanking operation 604. After detecting a data transmission with a blanking operation 604 from the first NAP, the other NAPs may suspend their current decrementing backoff counters for channel contention, thereby delaying their respective channel contention backoff processes 605 and 606 by a predetermined time accordingly. After the predetermined time expires, the corresponding channel contention backoff processes 605 and 606 are initiated again.

[0046] Figure 7 A block diagram of a network node (NN) 700 according to various embodiments of the present invention is illustrated. NN 700 is an example of a wireless communication node that can be configured to implement the various methods described herein. In some embodiments, NN 700 can be a wireless communication node, such as an access point (AP), as described herein. In other embodiments, NN 700 can be a wireless communication device, such as a station (STA), as described herein. Figure 7 As shown in , NN 700 includes a housing 740 that contains a system clock 702 , a processor 704 , a memory 706 , a transceiver 710 including a transmitter 712 and a receiver 714 , a power module 708 , and a blanking module 720 .

[0047] In this embodiment, system clock 702 provides timing signals to processor 404 for controlling the timing of all operations of NN 700. Processor 704 controls the general operation of NN 700 and may include one or more processing circuits or modules, such as a central processing unit (CPU) and / or any combination of general purpose microprocessors, microcontrollers, digital signal processors (DSPs), field programmable gate arrays (FPGAs), programmable logic devices (PLDs), controllers, state machines, gating logic, discrete hardware components, dedicated hardware finite state machines, or any other suitable circuits, devices, and / or structures that can perform computations or other data operations.

[0048] The memory 706, which may include both a read-only memory (ROM) and a random access memory (RAM), may provide instructions and data to the processor 704. A portion of the memory 706 may also include a non-volatile random access memory (NVRAM). The processor 704 typically performs logic and arithmetic operations based on program instructions stored in the memory 706. The instructions (also referred to as software) stored in the memory 406 may be executed by the processor 704 to perform the methods described herein. The processor 404 and the memory 706 together form a processing system for storing and executing software. As used herein, "software" means any type of instruction, whether referred to as software, firmware, middleware, microcode, etc., which can configure a machine or device to perform one or more desired functions or processes. Instructions may include code (e.g., source code format, binary code format, executable code format, or any other suitable code format). When executed by one or more processors, the instructions cause the processing system to perform the various functions described herein.

[0049] The transceiver 710 including a transmitter 712 and a receiver 714 allows the NN 700 to transmit and receive data to and from an external network node (e.g., a STA or AP). The antenna 750 is typically attached to the housing 740 and electrically attached to the transceiver 710. In various embodiments, the NN 700 includes (not shown) multiple transmitters, multiple receivers, and multiple transceivers. In some embodiments, the antenna 750 includes a multi-antenna array that can form multiple beams according to MIMO beamforming technology, each of the beams pointing in a different direction.

[0050] The blanking module 720 may be implemented as part of the processor 704 programmed to perform the functions herein, or it may be a separate module implemented in hardware, firmware, software, or a combination thereof. According to various embodiments, the blanking module 720 is configured to perform interference blanking (attenuation) functions as described herein, such as performing channel state information (CSI) measurements, precoding calculations, data transmissions or acknowledgements (ACKs), clear to send (CTSs), or generating blanking transmissions, as discussed above. In some embodiments, the blanking module 720 may be implemented as software (i.e., computer executable instructions) stored in a non-transitory computer readable medium, which, when executed by the processor 704, converts the processor 704 into a special purpose computer to perform the blanking operations described herein.

[0051] The various components and modules discussed above within housing 740 are coupled together via bus system 730. Bus system 730 may also include, in addition to a data bus, a power bus, a control signal bus, and / or a status signal bus. It should be understood that the modules of NN 700 may be operably coupled to each other using any suitable techniques and media. It should also be understood that additional modules (not shown) may be included in NN 700 without departing from the scope of the present invention.

[0052] Although various embodiments of the present disclosure have been described above, it should be understood that they are presented by way of example only and not by way of limitation. Similarly, various figures may depict example architectures or configurations, which are provided to enable those of ordinary skill in the art to understand the example features and functions of the present disclosure. However, these people will understand that the present disclosure is not limited to the example architectures or configurations shown, but can be implemented using a variety of alternative architectures and configurations. In addition, as will be understood by those of ordinary skill in the art, one or more features of an embodiment may be combined with one or more features of another embodiment described herein. Therefore, the breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments.

[0053] It should also be understood that any reference to an element using names such as "first," "second," etc. herein generally does not limit the number or order of these elements. Instead, these names may be used herein as a convenient means of distinguishing two or more elements or instances of an element. Thus, reference to a first element and a second element does not mean that only two elements can be used, or that the first element must be before the second element in some way.

[0054] In addition, those skilled in the art will appreciate that information and signals may be represented using any of a variety of different techniques and methods. For example, data, instructions, commands, information, signals, bits, and symbols may be represented by voltage, current, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0055] Those skilled in the art will further appreciate that any of the various illustrative logical blocks, modules, processors, devices, circuits, methods, and functions described in conjunction with the aspects disclosed herein may be implemented by electronic hardware (e.g., digital implementations, analog implementations, or a combination of both), firmware, various forms of programs or design codes incorporating instructions (which, for convenience, may be referred to herein as "software" or "software modules"), or any combination of these technologies.

[0056] In order to clearly understand this interchangeability of hardware, firmware and software, various illustrative components, blocks, modules, circuits and steps have been generally described above according to their functions. Whether such functions are implemented as hardware, firmware or software, or a combination of these technologies, depends on the specific application and the design constraints imposed on the entire system. Skilled technicians can implement the described functions in various ways for each specific application, but such implementation decisions will not lead to departure from the scope of this disclosure. According to various embodiments, processors, devices, components, circuits, structures, machines, modules, etc. can be configured to perform one or more functions of the functions described herein. The term "configured to" or "configured for" used herein for a specific operation or function refers to a processor, device, component, circuit, structure, machine, module, signal, etc., which is physically constructed, programmed, arranged and / or formatted to perform a specific operation or function.

[0057] In addition, it will be understood by those of ordinary skill in the art that the various exemplary logic blocks, modules, devices, components, and circuits described herein may be implemented within or performed by an integrated circuit (IC), which may include a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic device, or any combination thereof. The logic blocks, modules, and circuits may also include antennas and / or transceivers to communicate with various components within a network or device. A processor programmed to perform the functions of this document will become a specially programmed or dedicated processor and may be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in combination with a DSP core, or any other suitable configuration to perform the functions described herein.

[0058] If implemented in software, these functions can be stored as one or more instructions or codes on a computer-readable medium. Therefore, the steps of the method or algorithm disclosed herein can be implemented as software, which is stored on a computer-readable medium. Computer-readable media include both computer storage media and communication media, including any medium that can transfer a computer program or code from one place to another. The storage medium can be any available medium that can be accessed by a computer. As an example and not limitation, such computer-readable media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, disk storage or other magnetic storage device, or any other medium that can be used to store the desired program code in the form of instructions or data structures and can be accessed by a computer.

[0059] In this article, the term "module" used herein refers to software, firmware, hardware, and any combination of these elements for performing the associated functions described herein. In addition, for the purpose of discussion, various modules are described as separate modules; however, it is obvious to those of ordinary skill in the art that two or more modules can be combined to form a single module that performs the associated functions according to the embodiments of the present disclosure.

[0060] Various modifications to the implementations described in this disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other implementations without departing from the scope of this disclosure. Therefore, this disclosure is not intended to be limited to the implementations shown herein, but to conform to the broadest scope consistent with the novel features and principles disclosed herein, as described in the appended claims.

Claims

1. A method for initiating a blanking transmission performed by a first wireless communication node, the method comprising: transmitting a control message to be received by a second wireless communication node, wherein the control message notifies the second wireless communication node to initiate the blanking transmission toward the first station; as well as During the transmission of the blanking transmission from the second wireless communication node to the first station, data is transmitted to the first station, wherein the data includes identifications of one or more wireless communication nodes that are permitted to transmit the blanking transmission, the one or more wireless communication nodes including the second wireless communication node.

2. The method according to claim 1, wherein the data further comprises at least one of the following: an identification of a wireless communication node; a group identifier of adjacent wireless communication nodes; Media Access Control (MAC) address; or Pairing identities of one or more neighboring wireless communication nodes that are permitted to transmit blanking transmissions and their corresponding data transmissions to one or more stations.

3. The method of claim 1, wherein a preamble or a physical layer (PHY) header of the data comprises at least one of: an identifier indicating a transmission blanking transmission; one or more identifiers of one or more neighboring wireless communication nodes; or Information associated with the control message.

4. The method according to claim 1, wherein the control message comprises at least one of the following: one or more identifications of one or more wireless communication nodes; one or more group identifiers of one or more wireless communication nodes; a pairing identifier of one or more adjacent wireless communication nodes; One or more MAC addresses; or Pairing identification of one or more neighboring wireless communication nodes that are permitted to transmit blanking transmissions and their corresponding data transmissions to one or more stations.

5. The method according to claim 1, wherein: After a predetermined period of time has elapsed, initiating transmission of the data to the first site; and The control message causes the second wireless communication node to initiate the blanking transmission after the predetermined time period has elapsed.

6. The method according to claim 5, further comprising: receiving a response message from the second wireless communication node after transmitting the control message, wherein the predetermined time period is determined based on a time when the response message is received, The blanking transmission is initiated after the predetermined time period has passed.

7. The method according to claim 6, wherein: a first duration of transmission from the first wireless communication node is included in the control message; A second duration of transmission from the second wireless communication node is included in the response message; and The duration of the blanking transmission is selected to be the longer of the first duration and the second duration.

8. The method of claim 1, wherein the control message is included in a transmission including the data transmitted to the first station.

9. The method according to claim 1, further comprising: transmitting the control message to the first station so that the first station transmits a response message to be received by the second wireless communication node, wherein the response message causes the second wireless communication node to select a second site based on at least one predetermined criterion, and A nulling operation is performed on data transmission from the second wireless communication node to the second station.

10. The method of claim 9, wherein the at least one predetermined criterion comprises: Whether the strength of a residual signal to be received by the first station as a result of the data transmission from the second wireless communication node to the second station is less than or equal to a predetermined threshold value.

11. The method of claim 1, wherein the control message includes information identifying the second wireless communication node.

12. A method for providing blanking transmissions performed by a first wireless communication node, the method comprising: receiving a control message from a second wireless communication node, wherein the control message notifies the first wireless communication node to initiate the blanking transmission toward the first station; as well as During the transmission of the blanking transmission to the first station, data is transmitted to the second station, wherein the data includes identifications of one or more wireless communication nodes that are permitted to transmit the blanking transmission, the one or more wireless communication nodes including the second wireless communication node.

13. The method according to claim 12, wherein the data further comprises at least one of the following: an identification of a wireless communication node; a group identifier of adjacent wireless communication nodes; Media Access Control (MAC) address; or Pairing identities of one or more neighboring wireless communication nodes that are permitted to transmit blanking transmissions and their corresponding data transmissions to one or more stations.

14. The method of claim 12, wherein a preamble or a physical layer (PHY) header of the data comprises at least one of: Indicates the flag of the transmission set to null; one or more identities of one or more neighboring wireless communication nodes; or Information associated with the control message.

15. The method according to claim 12, wherein the control message comprises at least one of the following: one or more identifications of one or more wireless communication nodes; one or more group identifiers of one or more wireless communication nodes; a pairing identifier of one or more adjacent wireless communication nodes; One or more MAC addresses; or Pairing identification of one or more neighboring wireless communication nodes that are permitted to transmit blanking transmissions and their corresponding data transmissions to one or more stations.

16. The method of claim 12, wherein: After a predetermined period of time has passed, initiating transmission of the data to the second site; and The control message causes the first wireless communication node to initiate the blanking transmission after the predetermined time period has elapsed.

17. The method according to claim 12, further comprising: transmitting a response message from the first wireless communication node after receiving the control message, wherein the predetermined time period is determined based on a time when the response message is transmitted, The blanking transmission is initiated after the predetermined time period has passed.

18. The method of claim 17, wherein: a first duration of transmission from the first wireless communication node is included in the response message; A second duration of transmission from the second wireless communication node is included in the control message; and The duration of the blanking transmission is selected to be the longer of the first duration and the second duration.

19. The method of claim 12, wherein the control message is included in a transmission including the data transmitted to the first station.

20. The method of claim 12, further comprising: receiving a response message transmitted from the first station, wherein the response message is transmitted in response to receiving the control message from the second wireless node, wherein the received response message causes the first wireless communication node to select a second station based on at least one predetermined criterion, and A null operation is performed on data transmission from the first wireless communication node to the second station.

21. The method of claim 20, wherein the at least one predetermined criterion comprises: Whether the strength of a residual signal to be received by the first station as a result of the data transmission from the first wireless communication node to the second station is less than or equal to a predetermined threshold value.

22. The method of claim 12, wherein the control message includes information identifying the first wireless communication node.

23. A first wireless communication node, comprising: A transceiver, the transceiver being configured to: transmitting a control message to be received by a second wireless communication node, wherein the control message notifies the second wireless communication node to initiate a blanking transmission toward the first station; as well as Data is transmitted to the first station during the transmission of the blanking transmission from the second wireless communication node to the first station, wherein the data includes identification of one or more wireless communication nodes that are permitted to transmit the blanking transmission, the one or more wireless communication nodes including the second wireless communication node.

24. The first wireless communication node of claim 23, wherein the data further comprises at least one of the following: an identification of a wireless communication node; a group identifier of adjacent wireless communication nodes; Media Access Control (MAC) address; or Pairing identities of one or more neighboring wireless communication nodes that are permitted to transmit blanking transmissions and their corresponding data transmissions to one or more stations.

25. The first wireless communication node of claim 23, wherein a preamble or a physical layer (PHY) header of the data comprises at least one of: an identifier indicating a transmission blanking transmission; one or more identifiers of one or more neighboring wireless communication nodes; or Information associated with the control message.

26. The first wireless communication node of claim 23, wherein the control message comprises at least one of the following: one or more identifications of one or more wireless communication nodes; one or more group identifiers of one or more wireless communication nodes; a pairing identifier of one or more adjacent wireless communication nodes; One or more MAC addresses; or Pairing identification of one or more neighboring wireless communication nodes that are permitted to transmit blanking transmissions and their corresponding data transmissions to one or more stations.

27. The first wireless communication node of claim 23, wherein the transceiver is further configured to transmit the data to the first station after a predetermined time period has elapsed.

28. The first wireless communication node of claim 23, wherein the transceiver is further configured to: After transmitting the control message, a response message is received from the second wireless communication node, wherein the predetermined time period is determined based on a time when the response message is received.

29. The first wireless communication node according to claim 28, wherein: a first duration of transmission from the first wireless communication node is included in the control message; A second duration of transmission from the second wireless communication node is included in the response message; and The duration of the blanking transmission is selected to be the longer of the first duration and the second duration.

30. The first wireless communications node of claim 23, wherein the control message is included in a transmission including the data transmitted to the first station.

31. The first wireless communication node according to claim 23, further configured to: transmitting the control message to the first station so that the first station transmits a response message to be received by the second wireless communication node, wherein the response message causes the second wireless communication node to select a second site based on at least one predetermined criterion, and A null operation is performed on data transmission from the second wireless communication node to the second station.

32. The first wireless communication node of claim 31 , wherein the at least one predetermined criterion comprises: Whether the strength of a residual signal to be received by the first station as a result of the data transmission from the second wireless communication node to the second station is less than or equal to a predetermined threshold value.

33. The first wireless communication node of claim 23, wherein the control message includes information identifying the second wireless communication node.

34. A first wireless communication node, comprising: A transceiver, the transceiver being configured to: receiving a control message from a second wireless communication node, wherein the control message notifies the first wireless communication node to initiate a blanking transmission toward the first station; and Data is transmitted to a second station during the transmission of the blanking transmission from the first wireless communication node to the first station, wherein the data includes identifications of one or more wireless communication nodes permitted to transmit the blanking transmission, the one or more wireless communication nodes including the second wireless communication node.

35. The first wireless communication node of claim 34, wherein the data further comprises at least one of: an identification of a wireless communication node; a group identifier of adjacent wireless communication nodes; Media Access Control (MAC) address; or Pairing identities of one or more neighboring wireless communication nodes that are permitted to transmit blanking transmissions and their corresponding data transmissions to one or more stations.

36. The first wireless communication node of claim 34, wherein a preamble or a physical layer (PHY) header of the data comprises at least one of: Indicates the flag of the transmission set to null; one or more identities of one or more neighboring wireless communication nodes; or Information associated with the control message.

37. The first wireless communication node of claim 34, wherein the control message comprises at least one of: one or more identifications of one or more wireless communication nodes; one or more group identifiers of one or more wireless communication nodes; a pairing identifier of one or more adjacent wireless communication nodes; One or more MAC addresses; or Pairing identification of one or more neighboring wireless communication nodes that are permitted to transmit blanking transmissions and their corresponding data transmissions to one or more stations.

38. The first wireless communication node of claim 34, wherein: After a predetermined period of time has passed, initiating transmission of the data to the second site; and The control message causes the first wireless communication node to initiate the blanking transmission after the predetermined time period has elapsed.

39. The first wireless communication node according to claim 34, further configured to: transmitting a response message from the first wireless communication node after receiving the control message, wherein the predetermined time period is determined based on a time when the response message is transmitted, The blanking transmission is initiated after the predetermined time period has passed.

40. The first wireless communication node of claim 39, wherein: a first duration of transmission from the first wireless communication node is included in the response message; A second duration of transmission from the second wireless communication node is included in the control message; and The duration of the blanking transmission is selected to be the longer of the first duration and the second duration.

41. The first wireless communications node of claim 34, wherein the control message is included in a transmission including the data transmitted to the first station.

42. The first wireless communication node according to claim 34, further configured to: receiving a response message transmitted from the first station, wherein the response message is transmitted in response to receiving the control message from the second wireless node, wherein the received response message causes the first wireless communication node to select a second station based on at least one predetermined criterion, and A null operation is performed on data transmission from the first wireless communication node to the second station.

43. The first wireless communication node of claim 42, wherein the at least one predetermined criterion comprises: Whether the strength of a residual signal to be received by the first station as a result of the data transmission from the first wireless communication node to the second station is less than or equal to a predetermined threshold value.

44. The first wireless communication node of claim 34, wherein the control message includes information identifying the second wireless communication node.

45. A non-transitory computer-readable storage medium storing computer-executable instructions that, when executed, perform the method of any one of claims 1 to 22.

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