Method, system and device for changing wireless transmission power based on path loss information

Abstract

A method may include, at a first station in a wireless network, receiving a path loss (PL) transmission from at least a second station, dynamically changing power used for transmissions from the first station to the second station based on the received PL information, determining PL values ​​for transmissions received at the first station from other stations, and sending, from the first station, a PL transmission including the determined PL value for at least one other station. The PL transmission is configured to be received by stations of the same wireless network and stations of different wireless networks. Corresponding devices and systems are also disclosed.

Description

[0001] This application is an international application of U.S. non-provisional application No. 16 / 572,195, filed on September 16, 2019, which claims the benefit of U.S. provisional patent application serial number 62 / 836,846, filed on April 22, 2019, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present disclosure relates generally to wireless systems and, more particularly, to wireless systems having devices with dynamic adjustment of transmit power based on operating environment. Background Art

[0003] Currently, the IEEE 802.11 wireless standard does not require stations (STAs) to control transmit (TX) power as long as the transmit (TX) power does not exceed a maximum allowed threshold (i.e., the spectral mask). In dense Wi-Fi deployment environments, transmissions on channels (e.g., 80 MHz channels) are limited by bandwidth contention for overlapping basic service sets (OBSS). For example, in dense deployments of mixed Wi-Fi STAs such as 802.11a, 802.11n, and 802.11ac, there is little chance of no contention on any of the 20 MHz channels within the 80 MHz bandwidth. As a result, opportunities to transmit on the entire 80 MHz bandwidth become rare, and overall throughput is impacted.

[0004] The upcoming IEEE 802.11ax standard specifies that TX power control should be adjustable at the STA to facilitate parallel transmissions in strong OBSS environments. However, there is no clear indication of how to utilize or establish TX power control. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 is a block diagram of a system according to an embodiment.

[0006] Figures 2A to 2C is a series of diagrams illustrating a system in which STAs can calculate path loss values ​​and distribute these values ​​to other STAs with beacon-like transmissions.

[0007] Figure 2D and 2E is a diagram further illustrating that STAs of a system may calculate path loss values ​​and distribute these values ​​to other STAs with beacon-like transmissions.

[0008] Figure 3 is a diagram illustrating information elements that may be included in a beacon-like transmission according to an embodiment.

[0009] Figure 4 is a diagram illustrating adjustable transmit (TX) power based on path loss according to an embodiment.

[0010] Figure 5 is a flow chart of a method for receiving a path loss beacon according to an embodiment.

[0011] Figure 6 is a flow chart of a method for sending a path loss beacon according to an embodiment.

[0012] Figure 7 is a flow chart of a method for adjusting power of data transmission based on path loss information according to an embodiment.

[0013] Figure 8A and 8B is a diagram illustrating the operation of a "good neighbor" transmission opportunity according to an embodiment.

[0014] Figure 9 is a flow chart illustrating a "good neighbor" transmission opportunity method according to an embodiment.

[0015] Figure 10 is a block diagram of a wireless communication device according to an embodiment.

[0016] Figure 11 is a block diagram of a wireless communication device according to another embodiment.

[0017] Figure 12 is a diagram of a system of Internet of Things devices according to an embodiment. DETAILED DESCRIPTION

[0018] According to an embodiment, a transmitting station (STA) of a wireless network (e.g., a basic service set, BSS) can determine and use the lowest possible transmit (TX) power that can ensure sufficient signal strength (e.g., signal-to-interference-plus-noise ratio, SINR) for its data to be correctly received at the destination STA. As a result, the transmitting STA can introduce the lowest possible interference or significantly reduced interference to other STAs in the network and any neighboring networks.

[0019] In some embodiments, some data transmissions can be performed in parallel between overlapping networks (overlapping BSSs, OBSSs). STAs on different networks can determine whether the received signal strength (e.g., received signal strength indicator, RSSI) of a transmission at a STA on an adjacent network will remain below the neighbor STA's interference threshold (e.g., clear channel assessment, CCA). If yes (i.e., not exceeding the threshold), the transmission can proceed. If no (i.e., exceeding the threshold), the transmission can be delayed or canceled.

[0020] According to an embodiment, STAs can exchange and broadcast path loss (PL) information to all compatible STAs within range. PL information can be instantaneous in nature, periodically updated and transmitted from each STA. Based on the PL information, the transmitting STA can use the PL information from itself to its destination (i.e., receiving) STA to determine the minimum required TX power. Each STA can use the PL information obtained from the most recent broadcast (e.g., beacon frame) sent from its destination STA.

[0021] According to an embodiment, a STA can determine the PL value from broadcasts sent by other STAs. In some embodiments, the broadcast may include a beacon frame with an information element (IE) containing a TX power value (for the transmitting STA) and one or more PL values ​​with an associated STA identifier (e.g., a MAC address). From this broadcasted STA identifier, the STA can determine its own PL value. After learning its PL value, the STA can transmit to the destination STA at a TX power that offsets PL loss. In some embodiments, a safety margin may be added above the minimum TX power to ensure throughput performance. The overall TX power may be lower than the system's maximum TX power or default TX power.

[0022] According to an embodiment, a STA can calculate a PL value based on broadcasts sent by other STAs. In some embodiments, the PL value of another STA can be determined based on the difference between the TX power value in the beacon from the other STA and the received signal strength (RSSI) at the receiving STA. Such a PL value can be stored and then included in the beacon transmitted by the STA.

[0023] In some embodiments, when a STA is transmitting to multiple STAs (e.g., a multicast frame), the transmitting STA may use a TX power determined to be offset from the highest PL among all destination STAs (plus an optional safety margin in some embodiments). When transmitting to all STAs (i.e., a broadcast frame), the transmitting STA may use the maximum allowed TX power.

[0024] In some embodiments, PL information may be periodically transmitted to all STAs of a wireless network as well as STAs of neighboring wireless networks.

[0025] In some embodiments, a STA can calculate an instantaneous PL report and exchange it with other compatible STAs in its own BSS and other BSSs. Based on this report, the STA can calculate the appropriate TX power to introduce minimal OBSS interference for simultaneous data transmissions in other BSSs. Based on the instantaneous PL information, compatible transmitting STAs can transmit data using the lowest possible TX power, which ensures sufficient SNR for their data to be correctly received at its destination STA. When all STAs operate in this manner, the transmitting STA can introduce the lowest possible interference to other STAs that are not the destination of its data. Therefore, if the communicating STA pairs are sufficiently separated, and if the RSSI of the TX power of one transmitting STA pair remains below the CCA sensing threshold of the other STA pairs, there is a higher probability that data transmissions can occur concurrently between OBSSs.

[0026] In the various embodiments that follow, like items are referred to by like reference numerals, but the preceding digits correspond to the figure numbers.

[0027] refer to Figure 1 , a system 100 according to an embodiment is shown in the figure. The system 100 may include an access point (AP) 102-0 and a plurality of STAs (104-0 to 104-2). The AP 102-0 may enable the STAs (104-0 to 104-2) to access one or more other networks. The AP 102-0 and the STAs (104-0 to 104-2) may communicate with each other via wireless transmissions to form a wireless network 106-0. When such communications are initiated, they may be conceptualized as occurring on a path. For example, Figure 1 Paths 108-0 through 108-2 are shown between STA 102-0 and various other devices of network 106-0. It will be appreciated that other STAs 104-1 and 104-2 have similar paths to other devices of the system.

[0028] exist Figure 1In the figure, STA 104-0 is shown as including a communication circuit 110, which can implement dynamic power control of the transmitted signal based on the received PL information of the destination device (e.g., STA or AP). It should be understood that any or all of the STA / APs (102, 104-0 to 104-2) can include such a communication circuit 110. The communication circuit 110 can include a PL section 112 and a transmit (TX) power control section 114. The PL section 112 can store PL information of the path to other STA / APs in the same wireless network 106-0 (and in some cases, devices in adjacent wireless networks). This PL information can be received by other devices (STA / AP) in the same wireless network 106-0 as well as devices in adjacent wireless networks. In some embodiments, the PL information can be updated over time, allowing the transmission to adapt as the environment changes.

[0029] Additionally or alternatively, the PL section 112 can determine the PL value based on transmissions received from other devices (STAs / APs). This PL information can then be transmitted back to the sending device. Such transmissions can be broadcast (addressed to all devices within range), sent directly to the sending device, or sent indirectly to the sending device (e.g., via an AP or other intermediary device).

[0030] The TX power control section 114 can adjust the transmit power used for transmissions to other STAs or APs. In particular, the TX power control section 114 can reduce the TX power from the maximum allowable level for transmission based on the destination's PL information, thereby minimizing the possibility of the transmission interfering with other nearby devices. In some embodiments, the TX power control section 114 can determine a TX power level that can take into account any PL and meet a certain minimum threshold (e.g., RSSI) for the destination, while transmitting below the maximum power level when possible. As just one example, the TX power control section 114 can provide the following transmit powers:

[0031] TX power = target RX + PL + margin

[0032] Where Target RX may be the desired power level at the receiving device, PL is the path loss from the transmitting device to the receiving device, and Margin is a predetermined amount of additional power used to help ensure the signal is received.

[0033] In this way, transmissions between wireless devices may be selectively reduced from a default or maximum power to reduce potential interference with other networks (eg, frequency bands).

[0034] In some embodiments, a STA may include PL information of devices outside its own wireless network. The STA may use this neighboring PL information to control its own transmissions, thereby reducing or eliminating interference to neighboring devices. For example, still referring to Figure 1 In addition to wireless network 106-0, there may be a neighboring wireless network 106-1, which may include one or more other STAs (one shown as 104-3) and optionally another AP 102-1. STA 104-0 of the first wireless network 106-0 may include PL information for a path 108-3 to STA 104-3 of the neighboring wireless network 106-1. STA 104-0 may monitor the channel on which neighboring STA 104-3 may be transmitting. If STA 104-0 determines that neighboring STA 104-3 is transmitting, it may adjust or postpone its own transmission to reduce or eliminate interference with the transmission of neighboring STA 104-3.

[0035] In an embodiment, wireless network 106-0 may be a basic service set (BSS) operating in accordance with an IEEE wireless standard. Wireless network 106-1 may be an overlapping BSS (OBSS) operating in accordance with the same or another IEEE wireless standard. In some embodiments, wireless network 106-0 may operate in accordance with the IEEE 802.11ax standard.

[0036] According to an embodiment, devices of a wireless network may transmit PL information to each other in any suitable manner, including directly (transmission from one device to another) and indirectly (transmission via another device, such as a shared AP, as just one example). In some embodiments, a device may use a beacon-like transmission to communicate PL information to other devices. A beacon-like transmission may be a transmission that can be received by multiple devices of the same wireless network and may be a beacon according to a standard or protocol. Reference will now be made to Figures 2A to 2E One such embodiment is described.

[0037] Figures 2A to 2E 2 is a sequence of diagrams illustrating the operation of a wireless system 200 including STAs 204-0 through 204-2. STAs 204-0 through 204-2 can communicate with each other wirelessly according to a predetermined standard or protocol. Such communication can include the transmission and reception of data frames or packets. Each STA can include its own PL section 210-0 through 210-2. The PL sections 210-0 through 210-2 can each include a computing section 212-0 through 212-2 and a data receiving section 214-0 through 214-2.

[0038] The calculation section (212-0 to 212-2) can generate a PL value based on transmissions received from other STAs. The PL value can represent the signal power difference between the strength of the signal at the transmitting STA and the signal at the receiving STA. The calculated PL value can then be transmitted for reception and storage by other STAs.

[0039] refer to Figure 2A , STA 204-0 may transmit a beacon-like transmission 216-0. The transmission 216-0 may have a format that allows it to be detected by other STAs of the system 200 (e.g., a type, address, or other fields that identify the transmission). The transmission 216-0 may take any suitable form, including a data frame or packet, and may include a transmit power value TX(0), which may correspond to the power level at the STA 204-0 when the transmission 216-0 is transmitted. The transmission 216-0 may be received by STA1 204-1 and STA2 204-2, which may extract the TX(0) value and determine the received signal strength (e.g., RSSI) of the transmission 216-0. Using these values, STA1 and STA2 (204-1 / 2) may calculate a PL value. Thus, STA1 204-1 may calculate and store the PL value "PL STA0->STA1" in its calculation portion 212-1, and STA2 204-2 may calculate and store the PL value "PL STA0->STA2" in its calculation portion 216-2.

[0040] The stations can then start sending their own beacons, thereby enabling all stations to accumulate the PL values ​​of all other STAs.

[0041] refer to Figure 2B , station STA 204-1 may transmit its own beacon-like transmission 216-1. Transmission 216-1 may include a TX power value TX(1), which may correspond to the power level at STA 204-1 at the time of transmission. In the illustrated embodiment, transmission 216-1 may also include PL information that has been calculated by STA 204-1 (i.e., PL STA0->STA1).

[0042] Transmission 216-1 may be received by STA0 204-0 and STA2 204-2, which may extract the TX(1) value and determine the received signal strength of transmission 216-1. Consequently, STA0 204-0 may calculate the PL value "PL STA1->STA0" in its calculation section 212-0, and STA2 204-2 may calculate the PL value "PL STA1->STA2" in its calculation section 212-2. Furthermore, STA0 204-0 may identify the PL value ("PL STA0->STA1") included in transmission 216-1 as corresponding to itself and, therefore, may extract the PL value and store it in its receive section 214-0.

[0043] refer to Figure 2C , occurs with Figure 2B The same general operation is shown, only now utilizing STA 204-2. STA 204-2 may send a beacon-like transmission 216-2, which may include a TX power value TX(2) and the PL value it has calculated. STA0 204-0 may store its corresponding PL value (i.e., PL STA0->STA2) and may calculate a PL value based on transmission 216-2 (STA2->STA0). Similarly, STA1 204-1 may store its corresponding PL value (i.e., PL STA1->STA2) and calculate a PL value based on transmission 216-2 (STA2->STA1).

[0044] refer to Figure 2D , the operation can be as follows Figure 2A However, in some embodiments, the STA receiving the transmission 216-3 may recalculate the PL value. Thus, the PL value "PL STA0->STA1" may be updated in the calculation portion 212-1 of STA1 204-1, and "PL STA0->STA2" may be updated in the calculation portion 212-2 of STA2 204-2.

[0045] refer to Figure 2E , eventually each STA (204-0 to 204-2) having a calculation part ( Figures 2A to 2E All STAs in the network will receive and store PL values ​​from other STAs. In addition, such PL values ​​can be periodically updated when transmissions are received.

[0046] In some embodiments, system 200 may be a BSS and / or OBSS operating in accordance with the IEEE 802.11ax standard. Furthermore, the transmissions (216-0 to 216-4) may be periodic beacon transmissions. Furthermore, the STAs (204-0 to 204-2) may or may not be part of the same wireless network.

[0047] According to an embodiment, a STA may periodically broadcast a beacon frame or other type of management frame, which may contain an IE with the TX power of the frame and one or more PL values ​​used by other STAs. Figure 3 An IE 322 that may be included in a data frame according to an embodiment is shown. The IE 322 may include a TX power value (TX) (i.e., the power of the transmission containing the IE), one or more PL values ​​(two PL values, shown as PLx, PLy), and a station identifier corresponding to the PL value.

[0048] In the example shown, TX power may be a 1-octet value indicating the TX power (in dBm) when the STA transmits a beacon frame containing IE 322. IE 322 may contain an array of PL values. Figure 3 An example of two PL values ​​is shown; however, if more than two compatible STAs are in range, the array may be larger, or the IE may store only one PL value. It should be understood that in some embodiments, the array of PL values ​​may include those for STAs that are not part of the transmitting device's BSS. Each PL value may be a 7-octet data structure with a 1-octet value for the PL (in dB) and a 6-octet MAC address of the STA whose beacon frame was received and decoded by the transmitting STA. In some embodiments, only the most recently calculated PL value may be included in the IE. As just one example, a STA may include PL values ​​generated within the past 100 ms or so. This helps ensure that the PL value reflects the current state of the wireless environment.

[0049] Figure 4 is a diagram illustrating control of RX power according to an embodiment. Figure 4Shows the power (PWR) and frequency (FREQ) of a broadcast channel 424 used by one or more wireless systems. A standard or protocol may indicate a first spectral mask 426 of the channel. Only as an example, the spectral mask 426 may be a default and / or maximum TX power. According to an embodiment, based on the PL value, the STA may transmit at a lower power than the default value. For example, the transmission to the first destination STA may essentially follow a lower power spectral mask 428-0, which is generated due to considering the path loss PLx to the destination STA. The transmission to the second destination STA (where the PL value is lower (Ply < PLx)) may follow an even lower power spectral mask 428-1.

[0050] It should be understood that the specific shape of the lower power spectral masks 428-0 / 1 is exemplary. Embodiments may achieve a lower TX power in any suitable manner, including but not limited to excluding specific frequencies and / or frequency ranges within the channel 424.

[0051] Figure 5 Is a flowchart of a method 530 according to an embodiment. The method 530 may be performed by a STA that receives a beacon-like transmission from another STA. The method 530 may include determining whether a beacon-like transmission is being received 530-0. Such an action may include detecting a data frame with a specific identifier that designates the data frame as a transmission including PL-related data. In the absence of such a beacon-like transmission (No from 530-0), the method 530 may continue with other (e.g., standard) operations 530-2.

[0052] If a beacon-like transmission is received (Yes from 530-0), the method 530 may calculate the PL value of the transmitting STA 530-4. Such an action may include any of the techniques described herein, including determining the received signal strength of the beacon-like transmission and subtracting such a value from the TX power value. The transmit power value may be included in the beacon-like transmission. However, in other embodiments, the beacon-like transmission may occur at a certain maximum power known to all compatible STAs in the system and thus may not be included in the beacon-like transmission.

[0053] The receiving STA may store the calculated PL value for subsequent transmissions (530-6). The receiving STA may also determine whether the beacon-like transmission includes PL information related to its own transmission (540-8). Such an action may include checking the beacon-like transmission for data (e.g., IE) including the station identifier (e.g., MAC address) of the receiving station. If the beacon-like transmission does not include such PL information (No from 530-8), the method 530 may continue with other (e.g., standard) operations 530-2.

[0054] If the beacon-like transmission includes PL information for the receiving STA (yes from 530-8), the PL information may be stored by the receiving STA and used to control the TX power 530-10 to the indicated destination STA. This power adjustment may take any suitable form, as described herein or an equivalent scheme. As just one example, the TX power may be selected to exceed the PL value sufficiently to enable the destination STA to detect the transmission, plus some safety margin, where the overall transmission is less than the maximum (or default) power level dictated by the standard / protocol under which the system operates.

[0055] Figure 6 6 is a flow chart of a method 632 according to another embodiment. Method 632 may be performed by a STA to send a beacon-like transmission with PL information to other STAs. Method 632 may include creating an IE 632-2 having a PL value and a TX power value. The PL value may take any of the forms described herein and may be a value calculated by the transmitting STA in response to transmissions received from other STAs. However, in alternative embodiments, such a value may be received from another device (e.g., an AP may collect the values ​​and send them to the STAs in its BSS). The TX power value may indicate the power at which the beacon-like transmission will be sent. In some embodiments, this may be the maximum allowable power.

[0056] Method 632 may then determine whether to send a beacon-like transmission 632-0. In some embodiments, this may include running a timer so that a beacon-like transmission is sent at a predetermined period. However, alternative embodiments may include any other triggering event, including but not limited to a request for PL information or a beacon by another device, or a STA detecting or being notified of a predetermined change in the operating environment.

[0057] If no beacon-like transmission has been sent (No from 632-0), method 632 may determine whether any new PL values ​​exist 632-4. This action may include determining whether a new (or updated) PL value has been calculated in response to a transmission from another STA. If a new PL value exists (Yes from 632-4), method 632 may update the IE (632-2). If no new PL value exists (No from 632-4), method 632 may return to 632-0.

[0058] When a beacon-like transmission is to be sent (yes from 632-0), method 632 can send a beacon-like transmission 632-8 using an IE containing the PL value and TX power. This transmission can be at the power level specified in the IE, and in some embodiments, can be full power as determined by the management system's standards / protocols.

[0059] According to an embodiment, a STA can adjust its TX power based on the PL information associated with the destination STA. If the STA decides to transmit data, it can retrieve the latest PL information from its memory. This value may have been recently sent by the destination STA in a beacon-like frame. If no PL information exists, the STA can transmit data at a predetermined (e.g., maximum allowed) TX power. If PL information does exist for the destination, the STA can transmit data using a TX power that offsets the expected PL from itself to the destination STA, plus an optional safety margin. This TX power can be lower than the default (e.g., maximum allowed) power level.

[0060] In some embodiments, if the data is not correctly received by the destination STA, the transmitting STA may increase the safety margin and then retransmit the data. Such steps may be repeated until the data is received or the maximum allowed TX power is reached.

[0061] For incompatible STAs (i.e., STAs that cannot adjust their TX power based on PL information) or for broadcast frames, data can be transmitted at a default TX power. Furthermore, if PL information for the destination STA is not available, the STA can transmit data at the default TX power. In some embodiments, if the PL information is outdated (not current enough), the STA can transmit data at the default TX power.

[0062] In the case of transmitting a multicast frame, assuming that the transmitting STA has the PL information of all destination STAs, the transmitting STA can use a TX power that can offset the highest PL among the destination STAs, plus a safety margin.

[0063] Figure 7 7 is a flow chart of another method 734 according to an embodiment. Method 734 may be performed by a STA when transmitting data to another STA. According to method 734, TX power may be adjusted based on the PL information of the destination STA. Method 734 may include starting data transmission operation 734-0. This action may be initiated by an application running on a device, as one of many possible examples. Method 734 may determine whether there is recent PL information for the destination STA 734-2. Such an action may include checking for PL information previously received and currently stored in a predetermined location. In some embodiments, such an action may also include accessing a time value (e.g., a timestamp) associated with the PL value to determine how recently the PL information was received. If no PL information exists for the destination (or such PL information is determined to be outdated) (No from 734-2), the method may transmit at a default power, which in the illustrated embodiment may be a maximum power 734-4.

[0064] If there is valid PL information for the destination (yes from 734-2), the method can transmit 734-6 at a reduced power level intended to exceed the expected PL plus some margin. In the embodiment shown, the TX power can be given by:

[0065] TX power = RSSI + PL + margin

[0066] Where RSSI can be the expected received signal strength indicator at the destination STA, PL is the path loss to the destination STA, and margin is the additional power level. However, any other suitable method that can take PI into account while maintaining a lower than default TX power can be used to achieve the reduced TX power. Once the TX power has been determined, the method can transmit data 734-8 at the determined TX power.

[0067] In the illustrated embodiment, the method 734 may then determine an acknowledgment (ACK) 734-10 of the receipt of the TX data. If an ACK is received (Yes from 734-10), the method 734 may return to 734-0. If an ACK is not received (No from 734-10), if the data transmission is at the maximum allowable power (Yes from 734-12), the method 734 may follow the action for failure to receive an ACK (e.g., retransmission) 734-14.

[0068] If the data transmission is not at the maximum allowable power (No from 734-12), the method 734 may increase the value used to calculate the TX power margin 734-16. In the illustrated embodiment, this increase includes doubling the TX margin. However, this should not be construed as limiting. The TX margin may be increased by a greater or lesser amount. Utilizing the new margin value, the TX power may then be updated 734-18. The method 734 may then retransmit the TX data (proceeding to 734-6 or 734-8).

[0069] According to an embodiment, wireless devices can control TX power based not only on PL information of devices of their own network, but also on potential interference from neighboring networks. This capability is referred to herein as "good neighbor" TX opportunity detection and will be referred to as Figure 8A and Figure 8B Although the description will be made with reference to overlapping networks operating according to the IEEE 802.11 standard, Figure 8A and Figure 8B , but this arrangement should not be construed as limiting. The capabilities described herein may be deployed in any other suitable wireless network.

[0070] Figure 8A and Figure 8B806-0 and an adjacent network (OBSS) 806-1. BSS 806-0 may include AP 802-0 and STAs 804-0 through 804-2. STA 804-1 may include communication circuitry 810 that may implement dynamic power control of a transmit signal based on PL information, as described herein or an equivalent scheme. Figure 8A and Figure 8B In the example of FIG, AP 802-0 and STA 804-0 also include such communication circuitry 810. However, a fewer or greater number of devices may include communication circuitry 810.

[0071] OBSS 806-1 may include its own AP 802-1 and STAs 804-3 and 804-4. STAs 804-3 and 804-4 may include communication circuitry 810. BSS 806-0 and OBSS 806-1 are configured to potentially use the same range of transmission frequencies. That is, the channels used by BSS 806-0 may be the same as, overlap with, or be part of the channels used by OBSS 806-1, and vice versa.

[0072] Still refer to Figure 8A and Figure 8B In the described operation, it is assumed that STA 804-3 in OBSS 806-1 is currently transmitting to STA 804-4. In addition, STA 804-1 in BSS 806-0 is preparing to transmit to STA 804-0.

[0073] When STA 804-1 has some data to send, it can first sense whether the medium is idle. As just one example, STA 804-1 can perform a carrier sensing operation on the channel and determine a TX opportunity based on its own threshold (e.g., CCA). If the TX opportunity exists within its own BSS 806-0, even if concurrent data transmission 836 occurs in OBSS 806-1, STA 804-1 can determine an adjusted TX power level that is less than the maximum value allowed to transmit to destination STA 804-0, as described with respect to various embodiments herein, or an equivalent scheme.

[0074] However, before performing the data transmission, STA 804-1 may also calculate the estimated received signal strength (e.g., RSSI) that will be generated at the concurrently transmitting STA 804-3 in OBSS 806-1. STA 804-1 may make such a determination in any suitable manner, but in some embodiments, it may use PL information 838 received from neighboring STA 804-3. If the estimated received signal strength at the concurrently transmitting neighboring STA 804-3 is below the interference threshold (e.g., CCA) of STA 804-3, STA 804-1 may initiate its data transmission request to the destination STA 804-0 in its BSS 806-0.

[0075] refer to Figure 8B , assuming that the data transmission of STA 804-1 is determined not to interfere with the concurrent data transmission 836 of neighboring STA 804-3. Therefore, STA 804-1 may perform concurrent data transmission 840 to STA 804-0. The TX power may be at a level less than the level that would trigger the CCA threshold at neighboring STA 804-3.

[0076] However, if STA 804-1 has determined that data transmission to STA 804-0 will interfere with the concurrent data transmission 836 of neighboring STA 804-3, the data transmission may be canceled or delayed.

[0077] In some embodiments, if the reduced TX power concurrent data transmission (e.g., 840) is unsuccessful, STA 804-1 may increase the TX power level, as described herein or an equivalent scheme. Each time STA 804-1 increases the TX power for retransmission, it may again determine the estimated impact (e.g., RSSI) at any concurrently transmitting STA in a neighboring BSS (e.g., OBSS 806-1). If the new estimated impact at any concurrently transmitting neighboring STA is below the neighboring STA's interference threshold (e.g., CCA), STA 804-1 may retransmit the data. Otherwise, STA 804-1 may delay data retransmission until the channel clears to avoid interference.

[0078] According to an embodiment, the throughput of multiple networks (e.g., BSSs) operating on the same channel can be improved if all networks perform "good neighbor" TX opportunity detection (as described herein or an equivalent scheme). In a worst-case scenario, STAs of neighboring BSSs can transmit data sequentially at the maximum allowable TX power as specified in current standards.

[0079] Figure 9is a flow chart of a method 942 for "good neighbor" TX opportunity detection according to an embodiment. The method 942 may be performed by a STA when sending data to another STA in an environment where neighboring STAs have concurrent data transmissions.

[0080] Method 942 may include starting a data transmission operation 942-0. Method 942 may determine whether a TX opportunity exists in its network 942-2. Such action may include the STA performing a CCA, etc. However, any suitable action may be taken according to the governing standards / protocols. If it is determined that there is no TX opportunity (No from 942-2), method 942 may delay or abandon the data transmission 942-18.

[0081] If it is determined that there is a TX opportunity (YES from 942-2), the method 942 may determine whether there is a PL loss for the destination STA 942-4. If there is no PL information for the destination STA (NO from 942-4), the method may transmit at a default power, which in the illustrated embodiment may be a maximum power 942-6. If there is valid PL information for the destination (YES from 942-4), the method may determine a reduced power level for transmission to the destination 942-8. This action may be consistent with Figure 7 The actions shown in 734-2, 734-4 and 734-6 are the same.

[0082] Based on the determined TX power (i.e., the TX power of 942-8 or the maximum power of 942-6), the method 942 may estimate the RSSI at the concurrently transmitting STA (of another BSS) 942-10. If the estimated RSSI is greater than the CCA at the concurrently transmitting STA (i.e., there is a possibility of interference) (Yes from 924-12), the method may delay or abandon the data transmission 942-18. If the estimated RSSI is not greater than the CCA at the concurrently transmitting STA (No from 924-12), the method may send data at the determined TX power 942-14. If an ACK is received for the data transmission (Yes from 942-16), the method 942 may return to 942-0.

[0083] If no ACK is received for the data transmission (No from 942-16), and if the data transmission is not at the maximum allowable power, the method 942 may increase the value of the margin to reach the TX power 942-20. Using the new margin value, the TX power 942-22 may then be updated, and the method 942 may return to 942-10 (determining the RSSI at the neighboring STA).

[0084] The various methods described herein can be performed by an AP or STA in any suitable manner. In some embodiments, such methods can take the form of microcode and firmware present in the MAC layer circuitry of a WLAN device. However, such specific implementations should not be construed as limiting.

[0085] Figure 10 1 is a block diagram of a device 1004 according to an embodiment. In some embodiments, device 1004 may be an implementation of a STA as described herein. Device 1004 may include communication circuitry 1010, a controller 1052, radio circuitry 1056, and input / output (I / O) circuitry 1058. Communication circuitry 1010 may be WLAN circuitry, including WiFi control circuitry 1010-0 and WiFi MAC circuitry 1010-1. The WLAN circuitry may operate in any suitable frequency band, including, but not limited to, the 2.4 GHz band, the 5.0 GHz band, and / or the 6.0 GHz band.

[0086] Wi-Fi MAC circuitry 1010-1 may include a PL section 1012 and a TX power control section 1014. PL section 1012 may include circuitry for storing PL information received from other devices via wireless connections. PL information may correspond to the expected signal power loss when transmitting from device 1004 to a destination device and may identify a value unique to each destination device. PL values ​​may take any of the forms described herein or equivalents. Furthermore, PL values ​​may be used for devices in the same network (e.g., BSS) as device 1004, but may also be used for devices in different networks (e.g., adjacent or overlapping BSSs). In some embodiments, PL section 1012 may also include circuitry for generating (and updating) PL values ​​for transmission to other devices, as described herein or equivalents. Such circuitry may include any suitable arithmetic logic circuitry that can calculate PL based on a signal received from another device. The arithmetic logic circuitry may include fixed logic, programmable logic, one or more processors that execute instructions, or any combination thereof.

[0087] The power control portion 1014 may include circuitry for controlling the TX power of the device 1004. In particular, the power control portion 1014 may adjust the TX power to a level below a default (e.g., maximum) power level based on the PL information of the destination, as described herein or an equivalent scheme. As in the case of the PL portion 1012, the power control portion 1014 may include any suitable arithmetic logic circuitry. In some embodiments, the power control portion 1014 may output a signal to the radio circuitry 1056 to control the TX power level.

[0088] Radio circuitry 1056 may include circuitry for receiving and transmitting signals according to at least one standard or protocol. Radio circuitry 1056 may include any suitable circuitry according to the selected protocol and, in some embodiments, may include physical interface (PHY) circuitry and baseband circuitry. Radio circuitry 1056 may control the TX power level based on signals / values ​​received from communication circuitry 1010. In some embodiments, radio circuitry 1056 may transmit / receive in any internationally recognized industrial, scientific, or medical (ISM) frequency band. In some embodiments, radio circuitry 1056 may comply with IEEE 802.11 standards, such as IEEE 802.11ax.

[0089] Controller 1052 may control the operation of communication circuitry 1010. In some embodiments, controller 1052 may include circuitry (or instructions executable by the circuitry) for determining when to transmit and what data to include in the transmission. In some embodiments, PL values ​​may be stored in controller 1052 instead of or in addition to communication circuitry 1010. Controller 1052 may schedule path loss transmissions (e.g., beacons) from device 1004, including sending such transmissions in a periodic manner. In the illustrated embodiment, controller 1052 may include processor portion 1052-0 and memory portion 1052-1. Memory portion 1052-1 may include, or may be written to include, instructions for forming a PL-data frame, including creating an array of PL values ​​with corresponding identifiers. Memory portion 1052-1 may also be configured to store PL values ​​for subsequent transmission.

[0090] I / O circuitry 1058 may implement control of device 1004 by providing external input to device 1004. I / O circuitry 1058 may include circuitry for implementing communication with device 1004 according to any suitable method, including any of various serial data communication standards / methods, including but not limited to: Serial Digital Interface (SDI), Universal Serial Bus (USB), Universal Asynchronous Receiver Transmitter (UART), I / O, and the like. 2 C or I 2 S.

[0091] In some embodiments, device 1004 may be an integrated circuit device, where various parts are included in one integrated circuit package or formed in the same integrated circuit substrate.

[0092] Figure 111 is a block diagram of a device 1104 according to another embodiment. Device 1104 may be a compatible station as described in various embodiments herein and equivalents. Device 1104 may include communication circuitry 1110, a controller 1152, a radio portion 1156, I / O circuitry 1158, and an antenna connection 1160. Communication circuitry 1110 may include WLAN control circuitry 1110-0, MAC layer circuitry 1110-1, and physical layer (PHY) circuitry 1162.

[0093] The WLAN control circuit 1110-0 may enable communications to occur in accordance with one or more communication standards, including the IEEE 802.11ax standard, as just one example. Figure 11 In an embodiment, the WLAN control circuit 1110-0 may include a processor portion 1152-0 and a memory system 1152-1. The processor portion 1152-0 may include one or more processors configured to execute instructions stored in the memory system 1152-1. The processor portion 1152-0 may include one or more general-purpose processors and / or special-purpose processors. The memory system 1152-1 may include one or more memory types that may be configured to store instructions executable by the processor portion 1152-0 and to store data for use by the processor portion 1152-0. In some embodiments, the memory system 1152-1 may include random access volatile memory (e.g., dynamic and / or static RAM) and non-volatile read-only memory (e.g., flash memory).

[0094] WLAN control circuitry 1110-0 may provide various functions, including a PL beaconing function 1164, a PL calculation function 1112, and a TX power control function 1114. PL beaconing function 1164 may include assembling a PL data frame in memory system 1152-1 for transmission by device 1104. The PL data frame may have a type or other field that designates it as a beacon or other type of multicast data frame for reception by multiple other devices. The PL data frame may include PL values ​​generated (and periodically updated) by device 1104, which are currently being transmitted to other devices so that the other devices have PL values ​​for transmission back to device 1104. Each PL value may have a corresponding identifier (e.g., a MAC address). The PL data frame may also include the TX power of the beacon.

[0095] PL calculation functionality 1112 may generate a PL value based on transmissions detected from other devices. In some embodiments, PL calculation functionality 1112 may generate a PL value based on an RSSI value generated by radio portion 1156 and a TX power included in a data frame corresponding to the transmission that generated the RSSI value.

[0096] The TX power control function 1114 can generate a TX power value for an outgoing data frame. The TX power can be adjusted based on the PL value of the destination device, as described herein and equivalent schemes. In some embodiments, the TX power control function 1114 can also adjust the TX power value based on "good neighbor" TX opportunity detection, as described herein and equivalent schemes.

[0097] MAC layer circuitry 1110-1 can perform MAC layer operations, including merging appropriate headers, error correction, and length fields, as well as segmenting and reassembling data frames. MAC layer circuitry 1110-1 can receive data from and send data to WLAN control circuitry 1110-0 via backplane 1163. PHY layer circuitry 1162 can perform PHY layer operations, including, but not limited to, converting MAC layer data into a format suitable for the wireless medium being used, and controlling the modulation of outgoing data frames and the demodulation of incoming data frames.

[0098] Radio section 1156 may include radio circuitry 1166, power amplifier circuitry 1168, low noise amplifier (LNA) circuitry 1170, switch circuitry 1172, and filter circuitry 1174. Radio circuitry 1166 may convert data frames into appropriate radio signals for transmission, and receive radio signals for demodulation into data frames. Figure 11 In an embodiment, radio circuitry 1166 may include TX power circuitry 1176 and RSSI detection circuitry 1178. TX power circuitry 1176 may vary the TX power of power amplifier circuitry 1168 in response to a value received from WLAN control circuitry 1110-0 via MAC and PHY layer circuitry (1110-1, 1162).

[0099] The power amplifier circuit 1168 can establish the TX power for the data frame. The LNA circuit 1170 can amplify the received signal for processing by the radio circuit 1166. The switch circuit 1172 can selectively switch the antenna connection 1160 between the power amplifier circuit 1168 and the LNA circuit 1170. The filter circuit 1174 can filter the received signal according to the medium used. The antenna connection 1160 can be configured to connect to the antenna assembly. Although Figure 11 One antenna connection is shown, but embodiments may include multiple antenna connections.

[0100] While embodiments can benefit numerous applications where wireless systems are deployed, systems employing numerous networks in close proximity to one another can achieve significant improvements in performance and power savings.A specific example system of such a system will now be described by way of example.

[0101] Figure 12A site control system 1200 is shown according to an embodiment. The system 1200 may include various BSSs 1206-0, 1206-1, and 1206-2 operating relatively close to each other at a site. The BSSs 1206-0 to 1206-2 may be formed by APs 1202-0 to 1202-2 and STAs 1204-0 to 1204-5. The STAs 1204-0 to 1204-5 may be Internet of Things (IoT) type devices. While each STA 1204-0 to 1204-5 may have any suitable functionality, in the illustrated embodiment, STAs of the same BSS 1206-0 to 1206-2 may have the same functionality. For example, STAs 1204-0 to 1204-2 of BSS 1206-0 may be security devices, STAs 1204-3 and 1204-4 of BSS 1206-1 may be lighting devices, and STAs 1204-5 and 1204-6 of BSS 1206-2 may be control devices.

[0102] The BSSs (1206-0 to 1206-2) may all share the same channel or operate on channels that may overlap with each other.

[0103] Some or all of the STAs (1204-0 to 1204-6) may have TX power adjustment capabilities as described herein (eg, reducing TX power based on the PL value of the destination STA and / or based on the possible impact on concurrent transmissions in neighboring BSSs).

[0104] In conventional systems, multiple BSSs deployed adjacent to each other sharing the same channel may experience limited or impaired throughput performance due to mutual interference between OBSSs. However, according to an embodiment, STAs (1204-0 to 1204-6) can have instantaneous or near-instantaneous RSSI reporting for other compatible STAs and can adjust TX power to facilitate simultaneous traffic within each BSS. This can reduce interference between STAs (both within the same BSS and in adjacent BSSs) and reduce power consumption. In addition, this adaptive and dynamic change in TX enables TX power to change as the operating environment at the station changes.

[0105] While the various features of the embodiments are understood through this description, specific features of the embodiments may include:

[0106] 1. STA Path Loss IE Broadcast. Each compatible STA can periodically broadcast a beacon frame or other type of management frame at the maximum allowed TX power. Such a frame can contain the TX power value and the Path Loss IE.

[0107] 2. STA beacon reception. Each compatible STA can receive, decode, and save TX power and PL information for the transmission path between itself and other compatible STAs operating on the same channel (or overlapping channels). Therefore, each compatible STA can store the latest PL information for data transmission from itself to other compatible STAs.

[0108] 3. STA Data Transmission. Based on instantaneous or essentially instantaneous PL information, each compatible transmitting STA can transmit data using the lowest determined TX power that ensures sufficient SINR for its data to be correctly received at its destination STA with a certain safety margin. In the case of transmitting multicast frames, the transmitting STA can use a TX power that can achieve the highest PL offset for all destination STAs, plus a safety margin. Optionally, if these STA pairs are sufficiently far from each other and if the RSSI of the TX power of the transmitting STA in one pair remains below the CCA sensing threshold of the other STA pairs, some data transmissions can occur in parallel between OBSSs.

[0109] 4. STA data retransmission. If the data transmission is not correctly received by the destination STA, the transmitting STA can increase the TX power margin (e.g., double the margin) until the maximum allowed TX power is reached. The transmitting STA can then check the estimated RSSI at any concurrently transmitting STA in the neighboring BSS. If the estimated RSSI value is below the CCA threshold, the STA can retransmit the data. Otherwise, the STA can delay data retransmission until the channel clears to avoid OBSS interference.

[0110] 5. Incompatible STAs. For incompatible STAs, data can be transmitted using the maximum allowed TX power. In addition, if the PL information between a pair of STAs is not available, each STA can assume that the other partner is an incompatible STA that does not support PL-based TX power adjustment.

[0111] Various novel features presented by the embodiments will be recognized by those skilled in the art. Such features may include, but are by no means limited to:

[0112] 1) Practical implementation of TX power control and parallel data transmission between OBSS.

[0113] 2) IE in beacon (or other management) frames, which includes TX power and PL information. By broadcasting and receiving this information, each compatible STA can know the essentially instantaneous PL from itself to all other compatible STAs.

[0114] 3) For data transmission and retransmission, the transmitting STA may use the PL information to determine the minimum TX power necessary for successful reception of its data at the destination STA for unicast or the STA for multicast.

[0115] 4) Based on the PL information, the transmitting STA can determine whether parallel data transmission between OBSSs will occur by estimating the RSSI at the concurrently transmitting STAs in the neighboring BSS. This can reduce the OBSS interference level.

[0116] Embodiments may provide various advantages that will be apparent to those skilled in the art. One of these advantages is the ability for IEEE 802.11ax-compliant STAs to simultaneously transmit data across an 80 MHz bandwidth in an OBSS environment. This capability may provide improved traffic throughput, reduced TX power, or both compared to conventional approaches.

[0117] Embodiments can benefit battery-operated industrial or home IoT products where power consumption and overall throughput can be key differentiators for users. Improved power consumption and overall throughput can significantly increase the value of such products compared to products offering only conventional performance.

[0118] It should be understood that references throughout this specification to "one embodiment" or "an embodiment" mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Therefore, it is emphasized and should be understood that two or more references to "an embodiment," "one embodiment," or "an alternative embodiment" in various parts of this specification do not necessarily refer to the same embodiment. Furthermore, particular features, structures, or characteristics may be appropriately combined in one or more embodiments of the present invention.

[0119] Similarly, it should be understood that in the above description of exemplary embodiments of the present invention, various features of the present invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of simplifying the disclosure to help understand one or more of the various inventive aspects. However, this disclosure method should not be interpreted as reflecting an intention that the claims require more features than the features explicitly recited in each claim. On the contrary, the creative aspects lie in less than all the features of a single aforementioned disclosed embodiment. Therefore, the claims appended to the detailed description are hereby expressly incorporated into this detailed description, with each claim independently serving as a separate embodiment of the present invention.

Claims

1. A method comprising: At a first station in a wireless network compliant with at least one IEEE 802.11 standard, receiving a path loss (PL) transmission from at least a second station, the PL transmission comprising PL information corresponding to power loss in transmission from the first station to the second station, dynamically changing power used for transmissions from the first station to the second station based on received PL information, determining PL values ​​received at the first station from other stations for transmission, and sending, from the first station, a PL transmission comprising the determined PL value for at least one other station; The first station operates according to a predetermined communication standard; as well as At the first station: determining that a power level of a transmission to another station of the same wireless network is less than a maximum power level according to the communication standard, determining a power level received by a neighboring station of a different wireless network for the transmission, sending a transmission to the other station if the received power level is determined not to exceed a signal detection threshold level of the neighboring station, and If the received power level is determined to exceed the signal detection threshold level of the neighboring station, delaying or not sending a transmission to the other station, wherein The PL transmission is configured to be received by stations of the same wireless network and stations of different wireless networks.

2. The method according to claim 1, wherein Receiving the PL transmission includes receiving a data frame having a PL field and a station identification field.

3. The method according to claim 2, wherein: The station identification field includes a MAC address of the first station.

4. The method according to claim 1, wherein: Dynamically changing the power used for transmission includes: Determine the maximum power spectrum mask for the transmission channel, and Transmitting on the frequency of the channel at a power level below the spectrum mask.

5. The method according to claim 1, wherein: The first station and the second station operate according to a predetermined communication standard; and Dynamically changing the power used for transmission includes transmitting at an adjusted power level, the adjusted power level including: a target received power level at the second device, the PL value of the second device, and a predetermined margin value; in The adjusted power level is less than a maximum allowable power level according to the communication standard.

6. The method according to claim 1, wherein: Determining a PL value for a transmission received at the first station includes: receiving, from a transmitting station, a transmit TX power value corresponding to a power level of the transmission at the transmitting station, determining a received power value of the transmission at the first station, The receive power value is subtracted from the TX power value.

7. The method according to claim 6, wherein: Determining the received power value of the transmission at the first station includes generating a received signal strength indicator for the transmission from the sending station.

8. A wireless device comprising: Wireless communications circuitry compatible with at least one 802.11 wireless standard and comprising: a power control section configured to dynamically change transmit TX power for transmission to another device based on path loss PL information of the other device, the PL information corresponding to a TX power loss from the first device to the other device; a power detection section configured to detect the received signal strength of a data frame transmitted from another device, and The PL part is configured as follows: extracting PL information of other wireless devices from data frames received from the other wireless devices, and determining PL information of the other wireless device according to the data frame received from the other wireless device, wherein the PL information from the other wireless devices includes path loss information of at least one neighboring device that is part of a different wireless network; The power detection section is further configured to: prior to transmitting to another device of the same wireless network, determining a power level received at the at least one neighboring device for the transmission; and wherein, If the received power level is determined not to exceed a signal detection threshold level of the at least one neighboring device, sending a transmission to the other device, and If the received power level is determined to exceed a signal detection threshold level for the at least one neighboring device, transmissions to the other device are delayed or not sent.

9. The wireless device according to claim 8, wherein The PL part is the media access control MAC level circuit in the integrated circuit device.

10. The wireless device of claim 8, wherein: The PL part is also configured to: including PL information of at least one of the other wireless devices in a PL data frame, the PL data frame being configured to be received by the other wireless devices of the same or different wireless networks; as well as A radio circuit is configured to transmit the PL-data frame.

11. The wireless device of claim 10, wherein: The wireless device operates according to a predetermined communication standard; and The radio circuitry is configured to transmit the PL-data frame at a maximum power according to the communication standard.

12. The wireless device of claim 10, wherein: The radio circuit is configured to periodically transmit PL-data frames.

13. The wireless device of claim 8, wherein: The PL part includes at least one processor, and the at least one processor can be configured to: Extract the TX power value from a data frame received from another wireless device, Determine the received power value of the same data frame, and The receive power value is subtracted from the TX power value.

14. A system comprising: an access point device configured to connect station devices of a wireless network to at least one other network; as well as At least one station device, which communicates with the access point device through the wireless network, the at least one station device comprising: A communication circuit configured to: receiving path loss PL information from other station devices, the PL information corresponding to a signal strength loss from the at least one station device to the other station device, and dynamically reducing transmit TX power for transmission to another station device based on the PL information of the other station device, wherein the PL information from the other station devices includes path loss information of at least one neighboring device that is part of a different wireless network; The communication circuit is further configured to: Before transmitting to another station device of the wireless network, determining a power level received at the at least one neighboring device for the transmission, If the received power level is determined not to exceed the signal detection threshold level of the at least one neighboring device, sending a transmission to the other station device, and If the received power level is determined to exceed a signal detection threshold level for the at least one neighboring device, transmissions to the other station device are delayed or not sent.

15. The system of claim 14, wherein: The communication circuit is further configured to: determining PL values ​​of transmissions received by the at least one station device from other station devices, and The determined PL value is transmitted for reception by the other station device.

16. The system of claim 15, wherein: The communication circuit is further configured to periodically transmit the determined PL value in a beacon-like transmission.

17. The system of claim 14, wherein: The PL information includes a PL data field storing a PL value and an identification field storing a unique identifier of the another station device.

18. The system of claim 14, wherein: The wireless network operates according to a predetermined communication standard; and The communication circuit is further configured to transmit at full power according to the communication standard to station devices in the wireless network that do not have PL information.

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