Avoiding MAC padding in trigger-based PPDUs

Abstract

A radio station (STA) 103A in a wireless local area network (WLAN) 100 implements a method for avoiding media access control (MAC) padding of trigger-based (TB) physical layer convergence protocol data units (PPDUs) (e.g., trigger-based (TB) PPDUs). The method may reduce current or power consumption by the STA, which may optimize the STA, and potentially the WLAN 100 as a whole. In one example, the method includes the STA receiving a trigger frame from an access point (AP) 101. The trigger frame specifies a length of the PPDU. The method further includes the STA generating a TB PPDU based on the specification in the trigger frame. In particular, the STA generates a PPDU having a length shorter than the length specified by the trigger frame. The method also includes the STA transmitting the generated PPDU to the AP.

Description

Technical Field

[0001] In the Institute of Electrical and Electronics Engineers (IEEE) 802.11ax protocol, an access point (AP) can communicate with multiple stations (STAs) simultaneously. In one scenario, the AP transmits a trigger frame to an STA to discover data that the STA desires to transmit to the AP. Each of the STAs responds to the AP's trigger frame using a physical layer convergence protocol data unit (PPDU) that contains the requested information.

[0002] When generating a PPDU, the STA may need to pad the PPDU to meet the length of the PPDU defined in the trigger frame. Most of the padding is done at the media access control (MAC) layer by adding dummy frames to reach the defined length. PPDU length equalization is used to avoid or minimize potential transient events that can occur when the STA stops transmitting its PPDU in the middle of an uplink (UL) transmission. These transient effects can reduce the error vector magnitude (EVM) of the PPDU. In addition, the transmission of padding in a PPDU may require more resources than the transmission of data in the PPDU. For example, the current or time associated with the transmission of padding in a PPDU may be undesirably large compared to the current or time associated with the transmission of data in the PPDU. Furthermore, the current or power consumption in the case of UL transmissions subject to the AP's grouping policy can be affected by unpredictability and instability.

Summary of the Invention

[0003] In a wireless local area network (WLAN), a radio station (STA) implements a method to avoid media access control (MAC) padding in IEEE 802.11ax trigger-based (TB) physical layer convergence protocol data units (PPDUs). This method can reduce the current consumption by the STA, thereby optimizing the STA and, in some cases, the entire WLAN. In one example, this method includes the STA receiving a trigger frame from an access point (AP). The trigger frame specifies the length of the TB PPDU. This method further includes the STA generating a TB PPDU based on the specification in the trigger frame. In particular, the STA generates a TB PPDU with a length shorter than the length specified by the trigger frame. This method also includes the STA transmitting the generated TB PPDU to the AP.

[0004] In another example, the method described above in the paragraph above may be implemented using one or more non-temporary computer-readable media. In addition, the method described above in the paragraph above may be implemented by an apparatus having means for performing the operation of the method.

[0005] For detailed explanations of various examples, please refer to the attached drawings below. [Brief explanation of the drawing]

[0006] [Figure 1] This is a diagram illustrating an example architecture of a network system.

[0007] [Figure 2A] This timing diagram shows the interaction between an exemplary access point (AP) and an exemplary radio station (STA) in a network system designed according to the IEEE 802.11ax protocol. [Figure 2B]This timing diagram shows the interaction between an exemplary access point (AP) and an exemplary radio station (STA) in a network system designed according to the IEEE 802.11ax protocol.

[0008] [Figure 3] This figure shows an illustrative graph that highlights the gradual decrease in gain over time caused by the gradual shutdown of an example radio station (STA).

[0009] [Figure 4] This figure shows electronic devices according to several examples.

[0010] [Figure 5] This figure shows the components of an electronic device according to several examples. [Modes for carrying out the invention]

[0011] The examples described herein relate to one or more devices (e.g., a radio station (STA), an access point (AP), etc.) configured to operate in a network (e.g., a wireless local area network (WLAN), etc.) designed according to a wireless protocol (e.g., the IEEE 802.11ax protocol, any other IEEE 802.11 protocol, any other suitable wireless protocol, or any combination thereof). In one scenario, the exemplary STA generates a trigger-based (TB) physical layer convergence protocol data unit (PPDU) in response to receiving a trigger frame from the AP. In this scenario, the generated TB PPDU has a shorter length than the length specified by the trigger frame. The shorter length of the generated TB PPDU is due to the generated TB PPDU containing little to no padding. Thus, the amount of current or power associated with the transmission of the generated TB PPDU can be reduced. More specifically, the current or power associated with the transmission of the generated TB PPDU is less than the current or power associated with the transmission of a TB PPDU with a length specified by the trigger frame. The current or power savings resulting from the generated TB PPDU can improve the operation of the STA and, in some scenarios, the network itself.

[0012] Figure 1 is a diagram of an exemplary architecture of system 100 of a network (e.g., a local area network (LAN), a wireless LAN (WLAN), etc.). The following description is provided for exemplary system 100 operating with wireless protocols (e.g., the IEEE 802.11ax protocol, any other IEEE 802.11 protocol, any other suitable wireless protocol, any combination thereof, etc.). In particular, exemplary system 100 is not limited to the IEEE 802.11ax protocol and is applicable to other protocols or combinations of protocols that benefit from the principles described herein, such as current or future IEEE 802.11 protocols.

[0013] As shown in Figure 1, the system 100 includes an AP 101 coupled to an antenna array 105. The antenna array 105 shown in Figure 1 includes one antenna, but the antenna array 105 may include multiple antennas. In one example, the antenna array 105 is coupled to one or more receivers (not shown) of the AP 101, which are capable of receiving any number of signals. In one example, the antenna array 105 is coupled to one or more transmitters (not shown) of the AP 101, which are capable of transmitting any number of signals. The exemplary antenna array 105 may be communicatively coupled to one or more transceivers (not shown) of the AP 101, which are capable of receiving or transmitting any number of signals.

[0014] AP101 is sometimes called a wireless AP (WAP). AP101 can be a hardware device or node on a LAN or WLAN that enables devices (e.g., STA103A~103C, etc.) to connect to each other, to the Internet, or to other networks using a wireless standard (e.g., one of the following: IEEE 802.11 protocol, Bluetooth, etc.).

[0015] System 100 also includes, in particular, STA103A-103C capable of receiving frames or packets from AP101 and transmitting frames or packets to AP101. As shown in Figure 1, each of STA103A-103C includes a corresponding antenna array 107A-107C. Each of antenna arrays 107A-107C may include one or more antennas. Each antenna array 107A-107C may be communicatively coupled to one or more corresponding receivers (not shown) from among the STA103A-103C capable of receiving signals. In one example, each antenna 107A-107C may be communicatively coupled to one or more corresponding transmitters (not shown) from among the STA103A-103C capable of transmitting signals. In one example, each antenna 107A-107C is communicably coupled to one or more corresponding transceivers (not shown) from among STA103A-103C capable of receiving or transmitting signals. In one embodiment, each of STA103A-103C is a device capable of using one or more IEEE 802.11 protocols (e.g., IEEE 802.11ax protocol). An STA (e.g., any one of STA103A-103C) may be, for example, a laptop, desktop personal computer (PC), personal digital assistant (PDA), Wi-Fi phone, vehicle, wearable, tablet, or any other type of computing device operable by an end user. An STA (e.g., any one of STA103A-103C) may be fixed, mobile, or portable. At least one of the STA103A~103C devices includes an IEEE 802.11-compliant Media Access Control (MAC) and a Physical Layer (PHY) interface to a Wireless Media (WM).

[0016] As shown in Figure 1, AP101 can communicate with STA103A via a wireless or wired coupling mechanism 109A. Similarly, AP101 can communicate with STA103B via a wireless or wired coupling mechanism 109B. Likewise, AP101 can communicate with STA103C via a wireless or wired coupling mechanism 109C.

[0017] System 100 may be designed according to the IEEE 802.11ax protocol. In such a system, AP101 can utilize orthogonal frequency division multiplexing access (OFDMA), which enables parallel and simultaneous transmission of frames to multiple STAs (e.g., STA103A-103C). One feature of OFDMA is the subdivision of channels into smaller frequency allocations called resource units (RUs). To serve multiple STA103A-103Cs, AP101 allocates at least one RU to each of the STA103A-103Cs. After the allocation of RUs, uplink (UL) and downlink (DL) communications can occur simultaneously between AP101 and the multiple STA103A-103Cs over the RUs.

[0018] Multi-user multiplexed input / output (MU-MIMO) is another feature of System 100, designed according to the IEEE 802.11ax protocol. Like OFDMA, MU-MIMO also enables simultaneous UL and DL communication between AP101 and STA103A-103C. MU-MIMO includes using beamforming to direct signals to one or more intended wireless devices (e.g., AP101, one or more of STA103A-103C).

[0019] To coordinate UL OFDMA or UL MU-MIMO transmissions, AP101 can transmit trigger frames to STA103A-103C. Trigger frames are control frames that manage access to the WM and provide MAC layer reliability functions. More specifically, trigger frames identify common parameters (e.g., duration, guard interval (GI), etc.) for the next UL OFDMA or UL MU-MIMO transmission, allocate RUs (Rules of Use) for STA103A-103C, and define one or more transmission parameters for at least one of STA103A-103C. These transmission parameters include packet length, transmission power, modulation and coding scheme (MCS), number of spatial streams (NSS), channel width, modulation scheme, coding scheme, physical layer convergence protocol data unit (PPDU) format, bandwidth (BW), and PPDU duration.

[0020] After receiving a trigger frame, STA103A-103C respond in a synchronized manner. More specifically, STA103A-103C generate trigger-based (TB) packets. The TB packets can be TB PPDUs or any other TB packets used to respond to the trigger frame. STA103A-103C then send further TB packets to AP101 after a specified time interval called a short frame interval (SIFS). After AP101 receives the TB packets, AP101 generates one or more block acknowledgment (BA) frames (e.g., a BA frame for each STA103A-103C, a multi-STA BA frame for two or more STA103A-103C, etc.). AP101 then sends BA frames to STA103A-103C after the SIFS. Subsequently, UL OFDMA or UL MU-MIMO transmission can be initiated.

[0021] The trigger frame can determine the packet length for TB packets (e.g., TB PPDUs) generated by STA103A-103C. Typically, the packet length is the same for all TB packets that should be generated by STA103A-103C. In many scenarios, STA103A-103C include different amounts of data in each of their respective TB packets. For example, the amount of data that STA103A includes in its TB packet may be less or more than that that STA103B includes in its TB packet. However, the fact that each of the TB packets associated with STA103A-103C has the same length may necessitate padding some of the TB packets to meet length requirements. This phenomenon is sometimes called packet length equalization.

[0022] Padding involves filling unused portions of data structures (e.g., packets, frames, etc.) with bits, characters, and / or dummy frames. Padding may be performed at the end of a data structure to fill it with data. Data structures may be padded with "1" bits, whitespace characters, null characters, or dummy frames. In particular with respect to exemplary system 100, transmitting padded TB packets from STA103A-103C to AP101 may be suboptimal in some situations. For example, the amount of current or power associated with transmitting padded TB packets from STA103A to AP101 may be suboptimal. In particular, and in this example, the amount of current or power associated with transmitting the padding within a padded TB packet may be undesirably greater than the amount of current or power associated with transmitting the data portion of the padded TB packet. In such scenarios, current or power is wasted on transmitting non-essential data (e.g., padding).

[0023] The examples described in this specification can assist in reducing the amount of current or power associated with the transmission of TB packets generated by a STA. In one example, a STA (such as any one of STA103A - 103C) has data that does not satisfy a TB packet (such as a TB PPDU) with a specified length within a trigger frame received by the STA. In this example, the STA generates a TB packet having a length shorter than the length specified by the trigger frame. More specifically, the STA generates a TB packet with or without slight padding. The exemplary TB packet may be referred to herein as a shortened TB packet.

[0024] Assuming that there is little or no padding in the shortened TB packet, most or only the relevant or necessary data is included in the shortened TB packet. By minimizing or eliminating the padding in the TB packet, the amount of current or power associated with the transmission of the TB packet is reduced. That is, by transmitting a shortened TB packet (having a length shorter than the length specified by the trigger frame), one or more of the aforementioned drawbacks are avoided. In one example, the amount of current or power associated with the transmission of the data portion of the shortened TB packet is greater than the amount of current or power associated with the transmission of the padding of the shortened TB packet (if the shortened TB packet includes padding). In another example, and for a shortened TB packet without padding, there is no current or power dedicated to padding transmission. In either of the aforementioned examples, most or all of the current or power associated with the transmission of the shortened TB packet is dedicated to the transmission of the data portion of the shortened TB packet. In this way, the current or power dedicated to padding transfer is slight or non - existent. Assuming that current or power is saved by using shortened TB packets (instead of "full - length" TB packets), the operation or function of transmitting the STA of system 100 can be improved as a whole.

[0025] Figures 2A to 2B are timing diagrams showing the interaction between an exemplary access point (AP) 201 and exemplary wireless stations (STAs) 203A to 203C in a network system 200 designed according to the IEEE 802.11ax protocol. System 200 is the same as or similar to system 100 described above with respect to FIG. 1. As shown in FIGS. 2A to 2B, system 200 includes AP 201 and STAs 203A to 203C. AP 201 is the same as AP 101 described above with respect to FIG. 1.

[0026] In each of FIGS. 2A to 2B, the data exchange between AP 201 and STAs 203A to 203C is related to the time represented by the horizontal axis 243. The time increases in the right direction as shown by the horizontal axis 243. Thus, frames and packets are exchanged at specific times (e.g., t1, t2, t3, short inter-frame space (SIFS) 245, etc.).

[0027] Next, with respect to FIG. 2A, AP 201 generates a trigger frame 231. The trigger frame has been described above in connection with FIG. 1. Next, at time t1, AP 201 transmits trigger frame 231 to STAs 203A to 203C during time frame t1.

[0028] Following the reception of trigger frame 231, each of STAs 203A to 203C processes trigger frame 231 to generate a TB packet. More specifically, STA 203A processes trigger frame 231 to generate a TB packet 237, STA 203B processes trigger frame 231 to generate a TB packet 239, and STA 203C processes trigger frame 231 to generate a TB packet 241. Each of TB packets 237, 239, and 241 can be a TB PPDU or any other TB packet used to respond to a trigger frame (e.g., trigger frame 231, etc.).

[0029] After SIFS245A has elapsed, each of STA203A~203C transmits one of each of TB packets 237, 239, and 241 to AP201 during time frame t2. In response to receiving TB packets 237, 239, and 241, AP201 generates BA233. After SIFS245B has elapsed, AP201 transmits BA233 to STA203A~203C during time frame t3. After STA203A~203C receive BA233, UL OFDMA transmission or UL MU-MIMO transmission can be initiated. In one example, SIFS245A~245B have predetermined identical durations.

[0030] Each of the TB packets 237, 239, and 241 can be a TB PPDU. In some scenarios, the TB PPDU includes a legacy preamble, a high-efficiency (HE) preamble, and a payload, which may be referred to herein as data. In other scenarios, the TB PPDU further includes padding. As shown in Figure 2A, TB PPDU 237 includes a legacy preamble 205, an HE preamble 207, data 209, and padding 211. Furthermore, also shown in Figure 2A, TB PPDU 239 includes a legacy preamble 213, an HE preamble 215, data 217, and no padding. In addition, also shown in Figure 2A, TB PPDU 241 includes a legacy preamble 221, an HE preamble 223, data 225, and no padding / data.

[0031] A legacy preamble (for example, one of the legacy preambles 205, 213, and 221) allows legacy devices (for example, devices not designed to work with the IEEE 802.11ax protocol, etc.) to decode the TB PPDU. In other words, the legacy preamble is included in the TB PPDU for backward compatibility. The legacy preamble includes (i) a legacy short training field (L-STF), sometimes called a non-high-throughput (HT) short training field; (ii) a legacy long training field (L-LTF), sometimes called a non-HT training field; and (iii) a legacy signaling field (L-SIG), sometimes called a non-HT signaling field.

[0032] HE preambles (e.g., HE preamble 207, HE preamble 215, HE preamble 223, etc.) can only be decoded by devices designed to work with the IEEE 802.11ax protocol. HE preambles include (i) a repeating legacy signal field (RL-SIG), sometimes called a repeating non-HT signal field, an HE signal A field (HE-SIG-A), (iii) an HE signal B field (HE-SIG-B), (iv) an HE short training field (HT-STF), and (v) an HE long training field (HE-LTF).

[0033] The TB PPDU also includes the payload (e.g., data 209, data 217, data 225, etc.). This data may include the service field, the physical layer service data unit (PSDU), and the PPDU tail bits. Some of the bits in the service field may be used for synchronization in the receiver. The PSDU corresponds to the MAC protocol data unit (PDU) defined in the MAC layer and may contain data generated / used in higher layers. The PPDU tail bits may be used to return the encoder to a zero state.

[0034] Typically, legacy preambles (e.g., legacy preamble 205, legacy preamble 213, legacy preamble 221, etc.) have a predetermined size, and as a result, a predetermined amount of time (e.g., duration) needs to be transmitted to AP201. In addition, HE preambles (e.g., HE preamble 207, HE preamble 215, HE preamble 223, etc.) have a predetermined size, and as a result, a predetermined amount of time (e.g., duration) needs to be transmitted to AP201. However, payloads (e.g., data 209, data 217, data 225, etc.) may have different sizes from each other, and as a result, different amounts of time (e.g., duration) need to be transmitted to AP201. For example, as also shown in Figure 2A, data 225 is smaller than data 209, and data 209 is smaller than data 217. Therefore, in this example, the duration associated with the transmission of data 209, data 217, and data 225 will vary. Regardless of these differences, each of the TB PPDUs 237, 239, and 241 has a common information length 235 identified by the trigger frame 231. That is, each of the STAs 203A-C needs to communicate with one of each of the TB PPDUs 237, 239, and 241 within a specific time frame (t2) based on the common information length 235 indicated in the trigger frame 231. In such a scenario, one or more of the STAs 203A-203C may employ padding to ensure that their TB PPDUs fit the length identified by the trigger frame 231. For example, also with respect to Figure 2A, STA 203A generates a TB PPDU 237 containing a legacy preamble 205, an HE preamble 207, data 209, and padding 211. In this example, the data 209 is not long enough to satisfy the common information length 235. Therefore, STA203A pads the TB PPDU237 to ensure that the TB PPDU237 conforms to the length specified by the trigger frame 231.

[0035] An STA (for example, any one of STA203A-203C) does not always employ padding. For example, again with respect to Figure 2A, STA203B generates a TB PPDU239 containing a legacy preamble 213, an HE preamble 215, and data 217. In this example, data 217 has a length that satisfies the common information length 235. Therefore, STA203B does not pad the TB PPDU239.

[0036] In particular with respect to system 200 shown in Figure 2A, transmitting the padded TB PPDU 235 from STA103A to AP201 may be suboptimal in some situations. For example, the amount of current or power associated with transmitting the padded TB PPDU 235 from STA103A to AP201 may be suboptimal. In particular, and in this example, the amount of current or power associated with transmitting the padding 211 in the padded TB PPDU 235 may be greater than the amount of current or power associated with transmitting the data 209 in the padded TB PPDU 235. In such scenarios, current or power is wasted on the transmission of non-essential data (e.g., padding 211).

[0037] The examples described herein can help reduce the amount of current or power associated with the transmission of TB packets generated by the STA. In one example, and with reference to Figure 2A, the STA203C has data 225 in a trigger frame 231 received by the STA203C that does not meet the length of a TB PPDU 241 specified by the trigger frame 231. In this example, the STA203C generates a TB PPDU 241 with a length L1 shorter than the common information length 235 specified by the trigger frame 231. In particular, the STA203C generates a TB PPDU 241 without padding. This example of a TB PPDU 241 may be referred to herein as a shortened TB PPDU 241.

[0038] Assuming there is no padding within the shortened TB PPDU 241, only the relevant or necessary data 225 is contained within the shortened TB PPDU 241. By eliminating the padding within the TB PPDU 241, the amount of current or power associated with the transmission of the TB PPDU 241 is reduced. That is, by transmitting a shortened TB PPDU 241 (having a length L1 shorter than the length 235 identified by the trigger frame 231), one or more of the aforementioned drawbacks are avoided. For example, with respect to the shortened TB PPDU 241, there is no current or power dedicated to the transmission of padding. Therefore, most or all of the current or power associated with the transmission of the shortened TB PPDU 241 is directed towards the transmission of data 225. Assuming that current or power is saved by using a shortened TB PPDU (instead of a "full-length" TB PPDU 241, such as TB PPDU 237), the operation of transmitting STA203C or the functionality of system 200 as a whole may be improved.

[0039] Referring now to Figure 2B, another example of system 200 is shown. System 200 shown in Figure 2B is similar to system 200 shown in Figure 2A, except that in Figure 2B, STA203C generates a TB PPDU 249 and transmits it to AP201. The illustrative TB PPDU 249 includes a legacy preamble 221, an HE preamble 223, data 225, and padding 247. TB PPDU 249 is an example of a TB packet that can help reduce the amount of current or power associated with the transmission of TB packets generated by the STA. In one example, and with respect to Figure 2B, STA203C has data 225 that does not meet the length of a TB PPDU 247 specified in a trigger frame 231 received by STA203C. In this example, STA203C generates a TB PPDU 249 with a length L2 shorter than the common information length 235 specified by the trigger frame 231. In particular, STA203C generates a TB PPDU249 with padding 247 that does not fill the entire length of the TB PPDU249, as identified by the trigger frame 231. This exemplary TB PPDU249 may be referred to herein as the abbreviated TB PPDU249.

[0040] Assuming that only a small amount of padding 247 exists within the shortened TB PPDU 249, only relevant or necessary data 225 and a small amount of non-essential data (e.g., padding 247) are contained within the shortened TB PPDU 249. By minimizing the padding within the TB PPDU 249, the amount of current or power associated with the transmission of the TB PPDU 249 is reduced. That is, by transmitting a shortened TB PPDU 249 (having a length L2 shorter than the length 235 identified by the trigger frame 231), one or more of the aforementioned drawbacks are avoided. For example, with respect to the shortened TB PPDU 249, the current or power dedicated to the transmission of padding 247 is less than the current or power dedicated to the transmission of data 225. Therefore, a larger portion of the current or power associated with the transmission of the shortened TB PPDU 249 is dedicated to the transmission of data 225, and a smaller portion is dedicated to the transmission of non-essential data (e.g., padding 247). Assuming that current or power is saved by using the shortened TB PPDU249 (instead of the "full-length" TB PPDU such as TB PPDU237), the operation of the STA203C or the functionality of system 200 as a whole may be improved.

[0041] In Figures 2A and 2B, STA203C completes the transmission of shortened TB PPDUs (e.g., TB PPDU241, TB PPDU249, etc.) before the end of time frame t2. In some scenarios, STA203C shuts down after completing the transmission of shortened TB PPDUs (e.g., TB PPDU241, TB PPDU249, etc.). As a result, STA203C shuts down before any one of STA203A-203B shuts down. In many scenarios, STA203C may shut down abruptly. Initial and abrupt shutdowns of STA203C can affect the operation of STA203A-203B. Specifically, initial and abrupt shutdowns of STA203C can result in transient events that negatively impact the operation of STA203A-203B. To prevent transient events, the STA203C may, in one example, be designed to gradually shut down 251 after the transmission of shortened TB PPDUs (e.g., TB PPDU241, TB PPDU249, etc.) to the AP201. In one example, and as shown in Figures 2A and 2B respectively, the STA203C gradually shuts down 251 the radio frequency (RF) power associated with the transmission of shortened TB PPDUs (e.g., TB PPDU241, TB PPDU249, etc.) following the transmission of data 225 in the shortened TB PPDU. Figure 3, described below, provides additional details regarding the gradual shutdown of the STA when transmitting shortened TB PPDUs to the AP.

[0042] Figure 3 shows an illustrative graph 300 that highlights the gradual decrease in gain over time due to the gradual shutdown of an exemplary radio station (STA). Graph 300 includes a vertical axis 305 representing the gain in current (or power) associated with the exemplary STA, and a horizontal axis 307 representing the time associated with the shutdown of the exemplary STA after completing the transmission of TB packets (e.g., TB PPDU, shortened TB PPDU, etc.).

[0043] As explained above in Figures 1 to 2B, an STA (e.g., STA203C, as explained above in relation to Figures 2A to 2B) that transmits a shortened TB PPDU (e.g., TB PPDU241, TB PPDU249, etc.) to an AP (e.g., AP201, etc.) will complete its transmission before the length of time specified by the trigger frame (e.g., trigger frame 231, etc.). Typically, an STA transmitting a shortened TB PPDU will suddenly shut down after the transmission of the shortened TB PPDU. This sudden shutdown produces a sharp drop in gain, as shown by curve 303 in Figure 3. Conceptually, the sharp drop in gain shown by curve 303 can be likened to an ideal brickwall response 303. The sharp drop in gain can produce transient events that affect the operation of other STAs associated with the STA that transmitted the shortened TB PPDU.

[0044] In one example, an STA transmitting a shortened TB PPDU is designed to gradually shut down after transmitting the shortened TB PPDU to the AP. This gradual shutdown produces a gradual decrease in gain, as shown by curve 301 in graph 300. This gradual decrease in gain minimizes or eliminates the occurrence of transient events that could affect the operation of other STAs associated with the STA that transmitted the shortened TB PPDU.

[0045] Figure 4 shows an electronic device 400 according to several examples. The electronic device 400 may implement a base station, or AP (e.g., AP101, AP201, etc.), or STA (e.g., any one of STA130A-103C, any one of STA203A-203C, etc.), and / or any or all of any other elements / devices considered herein. The electronic device 400 may include one or more of the following: application circuit elements 405, baseband circuit elements 410, one or more radio front-end modules 415, memory circuit elements 420, power management integrated circuit elements (PMICs) 425, power circuit elements 430, network controller circuit elements 435, network interface connectors 440, satellite positioning circuit elements 445, and user interfaces 450. In some examples, the electronic device 400 may include additional elements such as memory / storage, displays, cameras, sensors, or input / output (I / O) interfaces. In other examples, the components described below may be included in multiple devices; that is, the electronic device 400 may span multiple devices.

[0046] As used herein, the term “circuit element” may refer to, be part of, or include hardware components such as electronic circuits, logic circuits, (shared, dedicated, or group) processors and / or (shared, dedicated, or group) memories, application-specific integrated circuits (ASICs), field-programmable devices (FPDs) (e.g., field-programmable gate arrays (FPGAs), programmable logic devices (PLDs), composite PLDs (CPLDs), high-capacity PLDs (HCPLDs), structured ASICs, or programmable system-on-a-chip (SoCs)), and digital signal processors (DSPs) configured to provide the functions described. In some examples, a circuit element may run one or more software or firmware programs to provide at least some of the functions described. In addition, the term “circuit element” may also refer to a combination of one or more hardware elements (or a combination of circuits used in an electrical or electronic system) with program code used to perform the functions of the program code. In these examples, a combination of hardware elements and program code may also be called a particular type of circuit element.

[0047] The terms “application circuit element” and / or “baseband circuit element” may be considered synonymous with “processor circuit element” and may be referred to as “processor circuit element.” As used herein, the term “processor circuit element” may refer to, be part of, or include a circuit element capable of performing a sequence of arithmetic or logical operations sequentially and automatically, or recording, storing, and / or transferring digital data. The term “processor circuit element” may refer to one or more application processors, one or more baseband processors, physical central processing units (CPUs), single-core processors, dual-core processors, triple-core processors, quad-core processors, and / or any other devices capable of executing computer executable instructions or performing other operations, such as program code, software modules, and / or functional processes.

[0048] Furthermore, the term “network element” may describe physical or virtualized equipment used to provide wired or wireless communication network services. The term “network element” may be considered and / or referred to as networked computer, networking hardware, network equipment, network node, router, switch, hub, bridge, wireless network controller, AP (e.g., AP 101, AP 201, etc.), gateway, server, virtualized virtual network function (VNF), network function virtualization infrastructure (NFVI), etc.

[0049] The application circuit element 405 may include one or more central processing unit (CPU) cores, as well as one or more of the following: cache memory, low dropout voltage regulators (LDOs), interrupt controllers, serial interfaces such as SPI, I2C, or universal programmable serial interface modules, timer counters including a real-time clock (RTC), interval and watchdog timers, general-purpose input / output (I / O or I / O), memory card controllers such as Secure Digital (SD) Multimedia Card (MMC), Universal Serial Bus (USB) interfaces, Mobile Industry Processor Interface (MIPI) interfaces, and Joint Test Access Group (JTAG) test access ports. In some examples, the electronic device 400 may not utilize the application circuit element 405 and instead may include a dedicated processor / controller for processing Internet Protocol (IP) data received from a network (e.g., a network designed according to the 802.11ax protocol, a network designed according to any other 802.11 protocol, etc.).

[0050] In addition or alternatively, application circuit elements 405 may include, but are not limited to, one or more field-programmable devices (FPDs) such as field-programmable gate arrays (FPGAs), programmable logic devices (PLDs) such as composite PLDs (CPLDs) and high-capacity PLDs (HCPLDs), ASICs such as structured ASICs, and programmable processors (PSoCs). In such examples, the circuit elements of application circuit element 405 may include logic blocks or logic fabrics and other interconnection resources that can be programmed to perform various functions, such as procedures, methods, and functions, in the various examples discussed herein (e.g., the generation of shortened TB PPDUs as described above in relation to Figures 1 to 3). In such examples, the circuit elements of the application circuit element 405 may include memory cells (e.g., erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, static memory (e.g., static random access memory (SRAM), antifuse, etc.)) used to store logic blocks, logic fabrics, data, etc., in lookup tables (LUTs), etc.

[0051] The baseband circuit element 410 may be implemented, for example, as one or more integrated circuits (ICs), a single-package IC soldered to a main circuit board, or as a soldering board including a multi-chip module containing two or more ICs. Although not shown, the baseband circuit element 410 may include one or more digital baseband systems that can be coupled via interconnect subsystems to a central processing unit (CPU) subsystem, an audio subsystem, and an interface subsystem. The digital baseband subsystem may also be coupled via another interconnect subsystem to a digital baseband interface and a mixed-signal baseband subsystem. Each of the interconnect subsystems may include a bus system, a point-to-point connection, a network-on-chip (NOC) structure, and / or some other suitable bus or interconnect technology. The audio subsystem may include digital signal processing circuit elements, buffer memory, program memory, audio processing accelerator circuit elements, data converter circuit elements such as analog-to-digital and digital-to-analog converter circuit elements, analog circuit elements including one or more amplifiers and filters, and / or other similar components. In some examples, the baseband circuit element 410 may include a protocol processing circuit element with one or more instances of a control circuit element (not shown) to provide control functions to the digital baseband circuit element and / or radio frequency circuit element (e.g., radio front-end module 415).

[0052] The user interface circuit element 450 may include one or more user interfaces designed to enable user interaction with the electronic device 400, or peripheral component interfaces designed to enable peripheral component interaction with the system 400. The user interface may include, but is not limited to, one or more physical or virtual buttons (e.g., a reset button), one or more indicators (e.g., light-emitting diodes (LEDs)), a physical keyboard or keypad, a mouse, a touchpad, a touchscreen, a speaker, or other audio-emitting devices, a microphone, a printer, a scanner, a headset, a display screen, or a display device. The peripheral component interfaces may include, but are not limited to, a non-volatile memory port, a Universal Serial Bus (USB) port, an audio jack, a power interface, or the like.

[0053] The radio front-end module (RFEM) 415 may include a millimeter-wave RFEM and one or more sub-millimeter-wave radio frequency integrated circuits (RFICs). In some implementations, one or more sub-millimeter-wave RFICs may be physically separated from the millimeter-wave RFEM. The RFICs may include connections to one or more antennas or antenna arrays, and the RFEM may be connected to multiple antennas. In alternative implementations, both millimeter-wave and sub-millimeter-wave radio functions may be implemented in the same physical radio front-end module 415. The RFEM 415 may incorporate both millimeter-wave and sub-millimeter-wave antennas. In one example, one or more RFEMs 415 transmit shortened TB PPDUs generated by application circuit elements 405 to APs (e.g., AP 101, AP 201, etc.). The generation and transmission of shortened TB PPDUs are described above in relation to Figures 1 to 3.

[0054] The memory circuit element 420 may include one or more volatile memories, including dynamic random access memory (DRAM) and / or synchronous dynamic random access memory (SDRAM), and non-volatile memories (NVM), including high-speed electrically erasable memory (commonly called flash memory), phase-change random access memory (PRAM), magnetoresistive random access memory (MRAM), etc. The memory circuit element 420 may be implemented as one or more of a solder-packaged integrated circuit, a socketed memory module, and a plug-in memory card.

[0055] The PMIC 425 may include a voltage regulator, a surge protector, a power alarm detection circuit element, and one or more backup power sources, such as a battery or capacitor. The power alarm detection circuit element may detect one or more of the brownout (undervoltage) and surge (overvoltage) conditions. The power circuit element 430 may provide power drawn from a network cable to provide both power supply and data connectivity to the electronic device 400 using a single cable.

[0056] The network controller circuit element 435 may provide connectivity to a network (e.g., a network designed according to the 802.11ax protocol, a network designed according to any one of the 802.11 protocols) using a standard network interface protocol such as Ethernet, Ethernet over GRE Tunnels, Ethernet over Multiprotocol Label Switching (MPLS), or some other suitable protocol. Network connectivity may be provided to / from electronic devices 400 via the network interface connector 440 using a physical connection that may be electrical (commonly called a "copper interconnect"), optical, or wireless. The network controller circuit element 435 may include one or more dedicated processors and / or FPGAs to communicate using one or more of the aforementioned protocols. In some implementations, the network controller circuit element 435 may include multiple controllers to provide connectivity to other networks using the same or different protocols.

[0057] The positioning circuit element 445 may include circuit elements for receiving and decoding signals transmitted by one or more navigation satellite constellations of a Global Navigation Satellite System (GNSS). Examples of navigation satellite constellations (or GNSS) may include, for example, the US Global Positioning System (GPS), Russia's Global Navigation System (GLONASS), the European Union's Galileo system, China's Beidou Satellite Navigation System, regional navigation systems, or GNSS augmentation systems (e.g., India's Regional Navigation Satellite System (NAVIC), Japan's Quasi-Zenith Satellite System (QZSS), France's DORIS (Doppler Orbitography and Radio-positioning Integrated by Satellite)). The positioning circuit element 445 may include various hardware elements for communicating with components of the positioning network, such as navigation satellite constellation nodes (e.g., hardware devices such as switches, filters, amplifiers, and antenna elements to facilitate over-the-air (OTA) communication).

[0058] Nodes or satellites in a navigation satellite constellation (GNSS nodes) can provide positioning services by continuously transmitting or broadcasting GNSS signals along a line of sight that can be used by GNSS receivers (e.g., positioning circuit elements implemented by positioning circuit elements 445 and / or STAs (e.g., any one of STA 103A-103C, any one of STA 203A-203C, etc.)) to determine their GNSS positions. The GNSS signals may include a message containing a pseudo-random code known to the GNSS receiver (e.g., a sequence of 1s and zeros), the transmission time (ToT) of the code epoch (e.g., a predefined point in the pseudo-random code sequence), and the GNSS node position at ToT. The GNSS receiver can monitor / measure GNSS signals transmitted / broadcast by multiple GNSSs (e.g., four or more satellites) and solve various equations to determine the corresponding GNSS positions. GNSS receivers typically also implement clocks that are less stable and precise than the atomic clocks of the GNSS nodes, and the GNSS receiver may use the measured GNSS signal to identify deviations from the true time of the GNSS receiver (e.g., the offset of the GNSS receiver clock relative to the GNSS node time). In some examples, positioning circuit elements 445 may include Micro-PNT (Micro-Technology for Positioning, Navigation, and Timing) integrated circuits (ICs) that use a master timing clock to perform position tracking / estimation without GNSS assistance.

[0059] A GNSS receiver can measure the time to arrival (ToA) of GNSS signals from multiple GNSS nodes according to its own clock. The GNSS receiver can determine the time-of-flight (ToF) value for each received GNSS signal from ToA and ToT, and then determine the three-dimensional (3D) position and clock deviation from the ToF. The 3D position can then be converted to latitude, longitude, and altitude. Positioning circuit element 445 can provide data to application circuit element 405, which may include one or more of position data or time data. Application circuit element 405 can use the time data to synchronize its operation with other radio base stations (e.g., AP 101, AP 201, etc.).

[0060] The components shown in Figure 4 can communicate with each other using interface circuit elements. As used herein, the term “interface circuit element” may refer to, be part of, or include a circuit element that provides information exchange between two or more components or devices. The term “interface circuit element” may refer to one or more hardware interfaces, such as buses, input / output (I / O) interfaces, peripheral component interfaces, network interface cards, etc. Any suitable bus technology may be used in a variety of implementations that may include any number of technologies, including industry standard architectures (ISA), extended ISAs (EISA), peripheral component interconnects (PCI), peripheral component interconnect extensions (PCIx), PCI Express (PCIe), or any number of other technologies. A bus may be a proprietary bus used, for example, in an SoC-based system. Other bus systems may include, in particular, I2C interfaces, SPI interfaces, point-to-point interfaces, and power buses.

[0061] Figure 5 is a block diagram showing components capable of reading instructions from a machine-readable or computer-readable medium (e.g., a non-temporary machine-readable storage medium) and implementing any one or more of the methods or techniques discussed herein, according to several examples. Specifically, Figure 5 shows a diagram of hardware resources 500 including one or more processors (or processor cores) 510, one or more memory / storage devices 520, and one or more communication resources 530, each of which may be communicatively coupled via a bus 540. As used herein, terms such as “computing resources” and “hardware resources” may refer to physical or virtual devices, physical or virtual components in a computing environment, and / or physical or virtual components in a particular device, such as computer devices, mechanical devices, memory space, processor / CPU time and / or processor / CPU usage, processor and accelerator load, hardware time or usage, power, input / output operation, ports or network sockets, channel / link allocation, throughput, memory usage, storage, networks, databases, and applications. For example, when node virtualization (e.g., NFV) is used, the hypervisor 502 may be executed to provide an execution environment to one or more network slices / subslice in order to utilize hardware resources 500. "Virtualized resources" may refer to computer, storage, and / or network resources provided to applications, devices, systems, etc. by the virtualization infrastructure.

[0062] Processor 510 (for example, a central processing unit (CPU), a reduced instruction set computing (RISC) processor, a multiple instruction set computing (CISC) processor, a graphics processing unit (GPU), a digital signal processor (DSP) such as a baseband processor, an application-specific integrated circuit (ASIC), a radio frequency integrated circuit (RFIC, another processor, or any suitable combination thereof) may include, for example, processors 512 and 514.

[0063] The memory / storage device 520 may include main memory, disk storage, or any suitable combination thereof. The memory / storage device 520 may include, but is not limited to, any type of volatile or non-volatile memory, such as dynamic random access memory (DRAM), static random access memory (SRAM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, or solid-state storage.

[0064] The communication resource 530 may include interconnection or network interface components or other suitable devices for communicating with one or more peripheral devices 504 or one or more databases 506 via the network 508. For example, the communication resource 530 may include wired communication components (for coupling via, for example, Universal Serial Bus (USB)), cellular communication components, NFC components, Bluetooth® components (e.g., Bluetooth® Low Energy), Wi-Fi® components, and other communication components. As used herein, the terms “network resource” or “communication resource” may refer to computing resources accessible by computer devices via a communication network. The term “system resource” may refer to any kind of shared entity for providing services, and may include computing and / or network resources. A system resource may be considered a set of coherent functions, network data objects, or services on a single or multiple hosts and accessible via a clearly identifiable server.

[0065] Instruction 550 may include software, programs, applications, applets, apps, or other executable code to cause at least one of the processors 510 to implement any one or more of the methods or techniques discussed herein. For example, instruction 550 may include executable code that enables the generation and transmission of shortened TB PPDUs, as described above in relation to Figures 1 to 3. Instruction 550 may reside entirely or partially within the processor 510 (e.g., in the processor's cache memory), the memory / storage device 520, or at least one of any suitable combination thereof. Furthermore, any part of instruction 550 may be transferred from any combination of peripheral devices 504 or database 506 to the hardware resource 500. Thus, the processor's memory 510, memory / storage device 520, peripheral devices 504, and database 506 are examples of computer-readable and machine-readable media.

[0066] At least one of the components shown in one or more prior drawings may be configured to perform one or more operations, techniques, processes, and / or methods shown in the examples considered herein. For example, a baseband circuit element described above in relation to one or more prior drawings may be configured to operate according to one or more of the examples considered herein. In another example, a circuit element associated with an STA, AP, network element, etc., as described above in relation to one or more prior drawings may be configured to operate according to one or more of the examples considered herein.

[0067] In this description, the term “coupled” means either an indirect or direct wired or wireless connection. Therefore, when a first device couples with a second device, the connection may be via a direct connection or via an indirect connection through other devices and connections. The phrase “based on” means “based at least partially on.” Therefore, if X is based on Y, X may be Y and any number of other factors. Also, the use of “A or B,” “A and / or B,” “A and B,” “at least one of A or B,” “at least one of A and B,” “A / B,” or “one or more of A and B” is intended to mean A only, B only, or A and B together.

[0068] Modifications to the described examples are permitted within the scope of the claims, and other examples are also permitted.

Claims

1. It is a method, The radio station (STA) receives a trigger frame that identifies the length of the trigger-based (TB) physical layer convergence protocol data unit (PPDU), The STA generates a TB PPDU, wherein the length of the generated TB PPDU is shorter than the specified length in the trigger frame. The STA transmits the generated TB PPDU, The STA is to gradually shut down after transmitting the generated TB PPDU, Methods that include...

2. The method according to claim 1, A method further comprising the STA receiving a block acknowledgment in response to the completion of the transmission of the generated TB PPDU.

3. The method according to claim 2, A method further comprising the STA refraining from transmitting any data in response to the completion of the transmission of the generated TB PPDU.

4. The method according to claim 3, The STA refrains from transmitting any data in response to the completion of the transmission of the generated TB PPDU. A method comprising refraining from transmitting any data before receiving the block acknowledgment by the STA.

5. The method according to claim 1, A method for generating the aforementioned TB PPDU, comprising padding the TB PPDU.

6. The method according to claim 1, A method wherein the generated TB PPDU includes a legacy preamble, a high-efficiency (HE) preamble, and data.

7. It is a device, A communication circuit element configured to transmit and receive data, A processing circuit element coupled to the aforementioned communication circuit element, The communication circuit element receives a trigger frame that identifies the length of a trigger-based (TB) physical layer convergence protocol data unit (PPDU). A TB PPDU is generated whose length is shorter than the specified length in the trigger frame. The generated TB PPDU is transmitted via the aforementioned communication circuit element. After transmitting the generated TB PPDU, the device is gradually shut down. The processing circuit element is configured as follows: A device including a device.

8. The apparatus according to claim 7, The apparatus is further configured such that the processing circuit element receives a block acknowledgment via the communication circuit element in response to the completion of the transmission of the generated TB PPDU.

9. The apparatus according to claim 8, The apparatus is further configured such that the processing circuit element refrains from transmitting any data via the communication circuit element in response to the completion of the transmission of the generated TB PPDU.

10. The apparatus according to claim 9, The apparatus further configured such that the processing circuit element refrains from transmitting any data through the communication circuit element before receiving the block acknowledgment.

11. The apparatus according to claim 7, The apparatus further comprises the processing circuit element configured to pad the TB PPDU.

12. The apparatus according to claim 7, The apparatus wherein the generated TB PPDU includes a legacy preamble, a high-efficiency (HE) preamble, and data.

13. One or more non-temporary computer-readable media, provided to a radio station (STA), The trigger receives a trigger frame that identifies the length of the trigger-based (TB) physical layer convergence protocol data unit (PPDU). This generates a TB PPDU whose length is shorter than the specified length in the trigger frame. The generated TB PPDU is then transmitted. After transmitting the generated TB PPDU, the STA is gradually shut down. One or more non-temporary computer-readable media containing instructions executable by one or more processors.

14. One or more non-temporary computer-readable media according to claim 13, One or more non-temporary computer-readable media further include instructions executable by the one or more processors to cause the STA to receive a block acknowledgment in response to the completion of the transmission of the generated TB PPDU.

15. One or more non-temporary computer-readable media according to claim 14, One or more non-temporary computer-readable media further include instructions executable by the one or more processors to cause the STA to refrain from transmitting any data in response to the completion of the transmission of the generated TB PPDU.

16. One or more non-temporary computer-readable media according to claim 15, One or more non-temporary computer-readable media further include instructions executable by the one or more processors to cause the STA to refrain from transmitting any data before receiving the block acknowledgment.

17. One or more non-temporary computer-readable media according to claim 13, One or more non-temporary computer-readable media further include instructions executable by the one or more processors to cause the STA to pad with TB PPDU.

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