Communication device and transmission method

Abstract

Various embodiments of the present invention relate to a communication device and a transmission method. A transmission method for improving transmission throughput of a communication device includes: receiving a wireless signal including a received packet; judging whether the received packet comes from the overlapping basic service set, and judging the duration of the transmission opportunity according to the information carried by the received packet; and when it is determined that the received packet comes from the overlapping basic service set, performing packet transmission in a spatial multiplexing manner within the duration of the transmission opportunity; and performing the packet transmission in a general manner after the duration of the transmission opportunity ends. The transmission power used by the spatial multiplexing method is different from the transmission power used by the general method, and the plurality of packets are transmitted in the spatial multiplexing method for the duration of the transmission opportunity.

Description

Technical Field

[0001] The present invention relates to a spatial reuse transmission method, and more particularly to a transmission method based on the application of spatial reuse transmission to further improve transmission throughput.

[0002] Background of the Invention

[0003] In modern life, there may be multiple Basic Service Sets (BSS) of Wi-Fi devices in the same space at the same time, causing Wi-Fi devices located in the overlapping Basic Service Set (OBSS) to find it difficult to find idle resources (such as idle time) for transmission due to the use of the Carrier Sense Multiple Access / Collision Avoidance (CSMA / CD) mechanism, which greatly reduces the transmission efficiency of the Wi-Fi devices.

[0004] To solve this problem, a transmission method that can effectively improve transmission throughput and a communication device that executes the transmission method are needed. Summary of the invention

[0005] According to an embodiment of the present invention, a communication device includes a wireless transceiver circuit and a baseband signal processing circuit. The wireless transceiver circuit is used to transmit and receive wireless signals, wherein the wireless signals include received packets. The baseband signal processing circuit is coupled to the wireless transceiver circuit and is used to process the received packets. The baseband signal processing circuit includes a decision unit and a transmission packet scheduling unit. The decision unit is used to determine whether the received packet comes from an overlapping basic service set, and to determine the length of the duration of the transmission opportunity based on the information carried by the received packet. The transmission packet scheduling unit is used to schedule the transmission of multiple packets. When the decision unit determines that the received packet comes from the overlapping basic service set, the transmission packet scheduling unit arranges the transmission of a first packet among the multiple packets within the duration of the transmission opportunity, and after the transmission of the first packet is completed, further determines whether the duration of the transmission opportunity has not ended, and after determining that the duration of the transmission opportunity has not ended, the transmission packet scheduling unit arranges the transmission of a second packet among the multiple packets within the duration of the transmission opportunity.

[0006] According to another embodiment of the present invention, a communication device includes a wireless transceiver circuit and a baseband signal processing circuit. The wireless transceiver circuit is used to transmit and receive wireless signals, wherein the wireless signals include received packets. The baseband signal processing circuit is coupled to the wireless transceiver circuit, and is used to process the received packets, determine whether the received packets are from an overlapping basic service set, and determine the length of the duration of the transmission opportunity based on the information carried by the received packets. When it is determined that the received packets are from the overlapping basic service set, the baseband signal processing circuit performs packet transmission in a spatial multiplexing manner during the duration of the transmission opportunity, and performs packet transmission in a general manner after the duration of the transmission opportunity ends. The transmission power used in the spatial multiplexing manner is different from the transmission power used in the general manner, and the baseband signal processing circuit transmits multiple packets in a spatial multiplexing manner during the duration of the transmission opportunity.

[0007] According to another embodiment of the present invention, a transmission method is provided to improve the transmission throughput of a communication device, comprising: receiving a wireless signal, wherein the wireless signal includes a received packet; determining whether the received packet is from an overlapping basic service set, and determining the length of the duration of the transmission opportunity based on the information carried by the received packet; and when determining that the received packet is from the overlapping basic service set, performing packet transmission in a spatial multiplexing manner during the duration of the transmission opportunity; and performing packet transmission in a general manner after the duration of the transmission opportunity ends. The transmission power used in the spatial multiplexing manner is different from the transmission power used in the general manner, and multiple packets are transmitted in a spatial multiplexing manner during the duration of the transmission opportunity. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 is a block diagram showing an example of a communication device according to an embodiment of the present invention.

[0009] Figure 2 is a block diagram showing an example of a baseband signal processing circuit according to an embodiment of the present invention.

[0010] Figure 3 is a flow chart showing an example of a transmission method according to an embodiment of the present invention.

[0011] Figure 4 FIG. 4 is a timing diagram of packet transmission for implementing a first contention mechanism according to an embodiment of the present invention.

[0012] Figure 5 is a flow chart showing a transmission method for implementing a first contention mechanism according to an embodiment of the present invention.

[0013] Figure 6 FIG. 4 is a timing diagram of packet transmission for implementing the second contention mechanism according to an embodiment of the present invention.

[0014] Figure 7 is a flow chart showing a transmission method for implementing a second contention mechanism according to an embodiment of the present invention. DETAILED DESCRIPTION

[0015] Figure 1 1 is a block diagram showing an example of a communication device according to an embodiment of the present invention. The communication device 100 may include at least an antenna 110, a wireless transceiver circuit 120, and a baseband signal processing circuit 130. It is worth noting that Figure 1 This is a simplified schematic diagram of a communication device, in which only components related to the present invention are shown. A person skilled in the art will appreciate that a communication device may include many components not shown in the figure. Figure 1 Components are shown to implement wireless communications and related signal processing functions.

[0016] The wireless transceiver circuit 120 is used to receive wireless signals through the antenna 110 and process the received wireless signals, or process the signals to be transmitted and transmit the corresponding wireless signals through the antenna 110. For example, the wireless transceiver circuit 120 can perform power amplification or attenuation processing on the signal, as well as up-conversion or down-conversion, to convert the baseband signal into a radio frequency signal or convert the radio frequency signal into a baseband signal. The baseband signal processing circuit 130 is used to process the baseband signal and control the operation of the communication device 100, including various operations, judgments, and signal generation, processing and transmission during the process of establishing a connection between the communication device 100 and another communication device and conducting wireless communication.

[0017] The communication device 100 can operate in accordance with the communication protocol specified by 802.11, and can be a device that supports spatial reuse. In an embodiment of the present invention, the communication device 100 can be used to implement a wireless access point (AP) in a basic service set (BSS), and can also be used to implement a station (Station) in a basic service set that accesses a network through a wireless access point.

[0018] In the wireless communication standard 802.11ax, a spatial reuse (SR) mechanism is established, which enables communication devices to transmit simultaneously during the transmission opportunities (Transmission Opportunity, abbreviated as TXOP) of other communication devices by adjusting the transmission end power and other methods, thereby achieving the effect of improving spectrum utilization. However, the 802.11 standard only describes the transmission regulations for transmitting a packet within the transmission opportunity of an OBSS. Therefore, in the prior art, when a communication device completes the transmission of a packet within the transmission opportunity time of other communication devices, the wireless communication standard does not specify how to transmit in the remaining time. From this behavior, it can be found that even if the SR mechanism established by the wireless communication standard is applied, a lot of time and opportunities for transmitting packets are still wasted. In particular, the longer the transmission opportunity period of the OBSS, the more serious the negative impact on the throughput and delay that users care about.

[0019] To solve this problem, the present invention proposes a transmission method (which can be regarded as an improved method based on the existing SR mechanism) that can effectively improve transmission throughput and reduce delay, and a communication device that executes the transmission method.

[0020] Figure 2 2 is a block diagram showing an example of a baseband signal processing circuit according to an embodiment of the present invention. The baseband signal processing circuit 200 may include a decision unit 210, a transmission packet scheduling unit 220, a memory unit 230 and a timer 240. In an embodiment of the present invention, the wireless signal received by the wireless transceiver circuit 120 may be converted from a radio frequency signal to a baseband signal after conversion, and the converted baseband signal may include a received packet. The baseband signal processing circuit 200 may process the received packet, and the decision unit 210 therein may determine whether the received packet is from an overlapping basic service set (OBSS). For example, in an embodiment of the present invention, the decision unit 210 may determine whether the received packet is from an OBSS based on the content set in the basic service set color (BSS color) field in the received packet. If the BSS color set in the received packet is different from the BSS color to which the communication device 100 currently belongs, it means that the received packet is from an OBSS. In contrast, if the BSS color set in the received packet is the same as the BSS color to which the communication device 100 currently belongs, it means that the received packet is not from the OBSS but from the BSS to which the communication device 100 belongs.

[0021] In the embodiment of the present invention, when it is determined that the received packet is from the OBSS, the decision unit 210 in the baseband signal processing circuit 130 / 200 can determine to perform packet transmission in a spatial multiplexing manner within the transmission opportunity duration (Duration) corresponding to the packet. On the contrary, when the received packet is not from the OBSS but from the BSS to which the communication device 100 belongs, the decision unit 210 in the baseband signal processing circuit 130 / 200 will suspend the execution of the packet transmission to avoid packet collision or interference.

[0022] More specifically, in the embodiment of the present invention, the decision unit 210 may determine the duration of the transmission opportunity according to the information carried by the packet, and set the timer 240 according to the length, so that the timer 240 counts a period of time equivalent to the length. When the timer 240 expires, a notification signal may be sent to notify the decision unit 210, or the decision unit 210 may periodically query to confirm whether the timer 240 has expired.

[0023] According to an embodiment of the present invention, the decision unit 210 can calculate how much transmission time the entire OBSS packet will occupy based on the length field in the Physical Layer Convergence Protocol (abbreviated as PLCP) header of this packet. Next, the decision unit 210 can check the duration field in the Media Access Control (MAC) header of this packet, and understand how long there will be packet transmission after the end of this packet through the value carried in this field. The decision unit 210 can determine the length of the duration of the transmission opportunity corresponding to this packet based on these two fields, so that it can be understood how long the channel will have OBSS packets in the future.

[0024] In addition, in an embodiment of the present invention, when it is determined that the received packet is from the OBSS, the decision unit 210 may set the value of the parameter SR_Period stored in the memory unit 230 to a first value, wherein the memory unit 230 may be a memory space with a length of 1 bit. In an embodiment of the present invention, the parameter SR_Period stored in the memory unit 230 is used to indicate the state of the spatial multiplexing period, or to indicate whether it is currently within the transmission opportunity duration corresponding to this packet. For example, when the value of the parameter SR_Period is set to 1, it means that it is currently in the spatial multiplexing period or is currently within the transmission opportunity duration corresponding to this packet. When the timer 240 expires, the decision unit 210 may change the value of the parameter SR_Period stored in the memory unit 230, for example, setting the value of the parameter SR_Period to a second value different from the first value to indicate that it is not currently in the spatial multiplexing period or is no longer within the transmission opportunity duration corresponding to this packet.

[0025] In an embodiment of the present invention, the transmission packet scheduling unit 220 can determine whether the duration of the transmission opportunity corresponding to this packet has ended according to the value of the parameter SR_Period, and perform packet transmission in a spatial multiplexing manner before the duration of the transmission opportunity corresponding to this packet ends.

[0026] Figure 3 is a flow chart showing an example of a transmission method according to an embodiment of the present invention. The transmission method can be used to improve the transmission throughput of the communication device 100, and includes the following steps performed by the communication device 100:

[0027] Step S302: Receive a wireless signal, wherein the wireless signal includes a received packet.

[0028] Step S304: Determine whether the received packet is from the OBSS, and determine the duration of the transmission opportunity according to the information carried by the received packet. When it is determined that the received packet is from the OBSS, execute step S306. When it is determined that the received packet is not from the OBSS, execute step S308.

[0029] Step S306: Perform packet transmission in a spatial multiplexing manner within the duration of the transmission opportunity corresponding to the received packet. In an embodiment of the present invention, before the duration of the transmission opportunity corresponding to the received packet ends, the communication device 100 may stop performing multiple packet transmissions in a spatial multiplexing manner in step S306. For example, the baseband signal processing circuit 130 may transmit multiple packets in a spatial multiplexing manner within the duration of the transmission opportunity corresponding to the received packet, and after determining that the duration of the transmission opportunity corresponding to the received packet ends, stop performing packet transmission in a spatial multiplexing manner and execute step S310.

[0030] Step S308: Wait for the duration of the transmission opportunity corresponding to the received packet to end.

[0031] Step S310: Perform packet transmission in a normal manner.

[0032] In an embodiment of the present invention, the transmission power used by the spatial multiplexing method is different from the transmission power used by the general method. For example, in order to avoid affecting the packet transmission of the OBSS, the transmission power used by the spatial multiplexing method may be lower than the transmission power used by the general method.

[0033] Reference Figure 2 The packet transmission in step S306 will be described in more detail below.

[0034] In an embodiment of the present invention, the transmission packet scheduling unit 220 is used to schedule the transmission of multiple packets. When the decision unit 210 determines that the received packet is from the OBSS, the transmission packet scheduling unit 220 may first arrange the transmission of the first packet within the duration of the transmission opportunity, and after the transmission of the first packet is completed, further determine whether the duration of the transmission opportunity corresponding to the received packet has not ended according to the value of the parameter SR_Period, and when it is determined that the duration of the transmission opportunity corresponding to the received packet has not ended, the transmission packet scheduling unit 220 may continue to arrange the transmission of the second packet within the duration of the transmission opportunity corresponding to the received packet.

[0035] More specifically, the transmission packet scheduling unit 220 may include a response unit 221, a transmission power control unit 222, multiple back-off engines 223-1, 223-2...223-N, and multiple queues 224-1, 224-2...224-N. The response unit 221 is used to determine whether it is still within the duration of the transmission opportunity corresponding to the received packet according to the value of the parameter SR_Period (for example, to determine whether the duration of the transmission opportunity has not yet ended), and to arrange the transmission of multiple packets in accordance with the selected competition mechanism. The transmission power control unit 222 is used to set the transmission power and rate used by the current packet according to the currently set transmission mode (for example, the aforementioned spatial multiplexing mode or general mode). Each queue is used to temporarily store a part of multiple packets to be transmitted and has a corresponding priority. Each back-off engine corresponds to a queue and is used to count the random back-off time for the corresponding queue.

[0036] The 802.11 standard defines a Quality of Service (QoS) mechanism that sends packets to four queues of different priorities according to their importance. For example, N may be a positive integer greater than or equal to four, so queues 224-1 to 224-N may include at least queues corresponding to the following four access categories AC_VO, AC_VI, AC_BE, and AC_BK with priorities from high to low, where AC is the abbreviation of Access Category, VO stands for Voice, VI stands for Video, BE stands for Best Effort, and BK stands for Background.

[0037] As described above, each queue corresponds to a backoff engine. When it is determined that a packet transmission is to be performed, each backoff engine 223-1 to 223-N will start counting the corresponding random backoff time, and in the process continue to monitor whether any packet is transmitted in the channel. If a packet is detected to be transmitted, the backoff engine will suspend the counting operation until the packet transmission is completed and the channel is confirmed to be idle before continuing the unfinished counting operation. The backoff engines 223-1 to 223-N will continue to count the corresponding random backoff time until one of the backoff engines completes the counting operation first, which means that the backoff engine that completes the counting operation first competes for the opportunity of this packet transmission.

[0038] As described above, when the response unit 221 determines that the duration of the transmission opportunity has not yet ended, the response unit 221 will determine to arrange the transmission of multiple packets (for example, the first packet and the second packet mentioned above) in a spatial multiplexing manner in accordance with the selected contention mechanism. In an embodiment of the present invention, the selectable contention mechanism includes a first contention mechanism and a second contention mechanism. According to an embodiment of the present invention, when the selected contention mechanism is the first contention mechanism, the backoff engine 223-1~223-N will respond to each packet transmission determined to be executed within the duration of the transmission opportunity (hereinafter referred to as OBSS-TXOP) corresponding to the received packet (that is, the packet determined to be from OBSS) to count the corresponding random backoff time. When the selected contention mechanism is the second contention mechanism, the backoff engine 223-1~223-N will only respond to the first packet transmission determined to be executed within the duration of OBSS-TXOP to count the corresponding random backoff time.

[0039] In other words, in the embodiment of the present invention, the first competition mechanism causes the fallback engines 223-1 to 223-N to compete for the opportunity of packet transmission again before each packet transmission, so that the multiple packets transmitted during the duration of the OBSS-TXOP (for example, the first packet and the second packet mentioned above) can be packets temporarily stored by different queues. The second competition mechanism only causes the fallback engines 223-1 to 223-N to compete for the opportunity of packet transmission before the first packet transmission, and after the transmission of a packet is completed, the queue corresponding to the fallback engine that successfully competed still provides subsequent packets. Therefore, the multiple packets transmitted during the duration of the OBSS-TXOP (for example, the first packet and the second packet mentioned above) will be packets temporarily stored by the same queue.

[0040] Figure 4 FIG. 4 is a timing diagram of packet transmission for implementing a first contention mechanism according to an embodiment of the present invention. Figure 4The bottom of the figure shows the transmission operation Tx and the receiving operation Rx performed by the communication device 100. From the receiving operation Rx of the communication device 100, it can be seen that the communication device 100 receives a packet from the OBSS, such as the physical layer protocol data unit (abbreviated as PPDU) OBSS-PPDU shown in the figure. In addition, the symbol OBSS-TXOP marked in the figure represents the transmission opportunity corresponding to the packet (OBSS-PPDU in this example) received from the OBSS by the communication device 100, and the parameter SR_Period marked in the figure shows the value set by the parameter SR_Period stored in the memory unit 230. In addition, the symbols AC_VO_BO and AC_BE_BO marked in the figure respectively show the countdown operation performed by the backoff engine corresponding to the access categories AC_VO and AC_BE, which counts the corresponding random backoff time in a countdown manner.

[0041] As described above, when it is determined that the received packet is from the OBSS, the decision unit 210 may set the value of the parameter SR_Period stored in the memory unit 230 to a first value within the duration of the OBSS-TXOP, for example Figure 4 The bit value with a high level as shown enables the decision unit 210 and the transmission packet scheduling unit 220 to determine whether the current state is still within the duration of the OBSS-TXOP through the value of the parameter SR_Period.

[0042] In an embodiment of the present invention, the decision unit 210 may determine to perform packet transmission in a spatial multiplexing manner within the duration of the OBSS-TXOP, and therefore, the transmission packet scheduling unit 220 may start scheduling the transmission of multiple packets, and the response unit 221 notifies the backoff engine corresponding to the queue that temporarily stores the packets to be transmitted to start the countdown operation, thereby counting the corresponding random backoff time to transmit on a competitive channel. Generally speaking, each backoff engine will first count the corresponding arbitration inter-frame space (Arbitration Inter-Frame Space, abbreviated as AIFS), and then count the corresponding random backoff time. For example, the first countdown operations 4, 3, 2, 1 performed by the backoff engine corresponding to the access category AC_VO and the first countdown operations 9, 8, 7, 6 performed by the backoff engine corresponding to the access category AC_BE in the figure. Figure 4 In the embodiment, the countdown operation performed by the communication device 100 is uniformly labeled as AIFS+BO.

[0043] According to an embodiment of the present invention, when the selected contention mechanism is the first contention mechanism, the fallback engine corresponding to the queue temporarily storing packets to be transmitted will respond to each packet transmission determined to be performed within the duration of the OBSS-TXOP to perform a corresponding countdown operation. Figure 4 In the example shown, at least two countdown operations occur within the duration of the OBSS-TXOP.

[0044] In this example, the first countdown operation starts at time point 1, and the first countdown operation is first completed by the backoff engine corresponding to the access category AC_VO. Therefore, at time point 2, the communication device 100 transmits the packets temporarily stored in the queue of the access category AC_VO in a spatial multiplexing manner (marked as SR in the figure), such as the packet PPDU (AC_VO) of the access category AC_VO shown in the figure. It should be noted that before the packet PPDU (AC_VO) of the access category AC_VO is actually transmitted, the response unit 221 can reconfirm the value of the parameter SR_Period to determine whether it is still within the duration of the OBSS-TXOP. If so, the packet PPDU (AC_VO) will be transmitted.

[0045] After the transmission of the packet PPDU (AC_VO) is completed, the response unit 221 can reconfirm the value of the parameter SR_Period to determine whether it is still within the duration of the OBSS-TXOP. If so, start the second countdown operation. Assuming that the second countdown operation is first completed by the fallback engine corresponding to the access category AC_BE, at time point 3, the communication device 100 transmits the packets temporarily stored in the queue of the access category AC_BE in a spatial multiplexing manner, such as the packet PPDU (AC_BE) of the access category AC_BE shown in the figure. Similarly, before the packet PPDU (AC_BE) is actually transmitted, the response unit 221 can reconfirm the value of the parameter SR_Period to determine whether it is still within the duration of the OBSS-TXOP. If so, the packet PPDU (AC_BE) will be transmitted.

[0046] On the other hand, if it is determined that the duration of the OBSS-TXOP has ended, and the countdown operation at this time is first completed by the backoff engine corresponding to the access category AC_VO, at time point 4, the communication device 100 transmits the packet temporarily stored in the queue of the access category AC_VO in a general manner, such as the rightmost packet PPDU (AC_VO) shown in the figure. In addition, in an embodiment of the present invention, the transmission power of the packet transmitted in a general manner may be different from the transmission power of the packet transmitted in a spatial multiplexing manner.

[0047] Figure 51 is a flow chart showing a transmission method for implementing a first contention mechanism according to an embodiment of the present invention. The transmission method can be used to improve the transmission throughput of the communication device 100, and includes the following steps performed by the communication device 100 (mainly the baseband signal processing circuit 130 / 200 therein):

[0048] Step S502: Receive a packet.

[0049] Step S504: Parse the BSS color field in the received packet, the Length field in the PLCP header, and the Duration field in the MAC header to obtain their set contents.

[0050] Step S506: Determine whether the packet is from the OBSS. If yes, go to step S508. If no, go to step S512.

[0051] Step S508: Set the value of the parameter SR_Period to a first value within the duration of the transmission opportunity (ie, OBSS-TXOP) corresponding to the received packet, for example Figure 4 The bit values ​​are shown having a high level (which may correspond to a value of 1).

[0052] Step S510: Determine whether the duration of the OBSS-TXOP has not ended according to the value of the parameter SR_Period, for example, determine whether the value of the parameter SR_Period is set to 1. If yes, directly execute step S514. If no, execute step S514 after step S512.

[0053] Step S512: Wait for the duration of the TXOP of the received packet to end.

[0054] Step S514: The back-off engines perform a countdown operation until one of them completes the countdown operation first. In the embodiment of the present invention, the back-off engine that completes the countdown operation first obtains the packet transmission opportunity, and the response unit 221 finds the packet in the corresponding queue and transmits the packet according to the transmission power recommended by the transmission power control unit 222.

[0055] Step S516: Determine whether the duration of the OBSS-TXOP has not ended according to the value of the parameter SR_Period, for example, determine whether the value of the parameter SR_Period is set to 1. If yes, execute step S518. If no, execute step S520.

[0056] Step S518: Perform packet transmission in a spatial multiplexing manner.

[0057] Step S520: Perform packet transmission in a general manner.

[0058] It is worth noting that in the embodiment of the present invention, if there are packets to be transmitted temporarily stored in one or more queues, after determining that the received packet is a packet from the OBSS, the communication device 100 can continue to perform packet transmission in a spatial multiplexing manner during the duration of the OBSS-TXOP. In contrast, if the received packet is not a packet from the OBSS, the communication device 100 must wait until the TXOP duration of this packet ends before performing packet transmission, and will perform packet transmission in a general manner.

[0059] In addition, it is worth noting that according to the first contention mechanism proposed by the present invention, after step S518 is completed, the process may return to step S510. If it is still within the duration of the OBSS-TXOP, the first contention mechanism proposed by the present invention may be used to compete for the opportunity of packet transmission again in step S514.

[0060] Figure 6 is a packet transmission timing diagram showing the implementation of the second contention mechanism according to an embodiment of the present invention. Figure 6 The bottom of the diagram shows the transmission operation Tx and the reception operation Rx performed by the communication device 100. From the reception operation Rx of the communication device 100, it can be seen that the communication device 100 receives a packet from the OBSS, such as the OBSS-PPDU shown in the figure. In addition, the symbol OBSS-TXOP marked in the figure represents the transmission opportunity corresponding to the packet (OBSS-PPDU in this example) received from the OBSS by the communication device 100, and the parameter SR_Period marked in the figure shows the value set by the parameter SR_Period stored in the memory unit 230. In addition, the symbols AC_VO_BO and AC_BE_BO marked in the figure respectively show the countdown operations performed by the backoff engines corresponding to the access categories AC_VO and AC_BE, which count the corresponding random backoff times in a countdown manner.

[0061] As described above, when it is determined that the received packet is from the OBSS, the decision unit 210 may set the value of the parameter SR_Period stored in the memory unit 230 to a first value within the duration of the OBSS-TXOP, for example Figure 6 The bit value with a high level as shown enables the decision unit 210 and the transmission packet scheduling unit 220 to determine whether the current state is still within the duration of the OBSS-TXOP through the value of the parameter SR_Period.

[0062] In an embodiment of the present invention, the decision unit 210 may determine to perform packet transmission in a spatial multiplexing manner within the duration of the OBSS-TXOP, and therefore, the transmission packet scheduling unit 220 may start scheduling the transmission of multiple packets, and the response unit 221 may notify the backoff engine corresponding to the queue temporarily storing the packets to be transmitted to start the countdown operation, thereby counting the corresponding random backoff time to transmit on the competitive channel.

[0063] According to an embodiment of the present invention, when the selected contention mechanism is the second contention mechanism, the fallback engine corresponding to the queue temporarily storing packets to be transmitted will only respond to the countdown operation performed by the first packet transmission determined to be performed within the duration of the OBSS-TXOP. Figure 6 In the example shown, the countdown operation is performed only once during the duration of the OBSS-TXOP.

[0064] In this example, the first countdown operation is completed first by the backoff engine corresponding to the access category AC_VO. Therefore, at time point 1, the communication device 100 transmits the packets temporarily stored in the queue of the access category AC_VO in a spatial multiplexing manner (marked as SR in the figure), such as the packet PPDU (AC_VO) of the access category AC_VO shown in the figure. It should be noted that before the packet PPDU (AC_VO) of the access category AC_VO is actually transmitted, the response unit 221 can reconfirm the value of the parameter SR_Period to determine whether it is still within the duration of the OBSS-TXOP. If so, the packet PPDU (AC_VO) will be transmitted.

[0065] After the transmission of the first packet PPDU (AC_VO) is completed, the response unit 221 can confirm the value of the parameter SR_Period again to determine whether it is still within the duration of the OBSS-TXOP. If so, after waiting for the short interframe space (SIFS), the communication device 100 continues to transmit the packets (if any) temporarily stored in the queue of the access category AC_VO in a spatial multiplexing manner at time point 2, such as the second packet PPDU (AC_VO) shown in the figure.

[0066] Similarly, after the transmission of the second packet PPDU (AC_VO) is completed, the response unit 221 confirms the value of the parameter SR_Period again to determine whether it is still within the duration of the OBSS-TXOP. If so, after waiting for SIFS, the communication device 100 continues to transmit the packets temporarily stored in the queue of the access category AC_VO (if any) in a spatial multiplexing manner at time point 3, such as the third packet PPDU (AC_VO) shown in the figure.

[0067] After the transmission of the third packet PPDU (AC_VO) is completed, the response unit 221 confirms the value of the parameter SR_Period again to determine whether it is still within the duration of the OBSS-TXOP. If it is determined that the duration of the OBSS-TXOP has ended, the response unit 221 notifies the backoff engine corresponding to the queue that temporarily stores the packets to be transmitted to start the countdown operation, thereby counting the corresponding random backoff time to compete for the channel for transmission again. In this example, the countdown operation after the duration of the OBSS-TXOP ends is first completed by the backoff engine corresponding to the access category AC_BE. Therefore, at time point 4, the communication device 100 transmits the packets temporarily stored in the queue of the access category AC_BE in a general manner, such as the rightmost packet PPDU (AC_VO) shown in the figure. In an embodiment of the present invention, the transmission power of the packet transmitted in a general manner may be different from the transmission power of the packet transmitted in a spatial multiplexing manner.

[0068] Figure 7 1 is a flow chart showing a transmission method for implementing a second contention mechanism according to an embodiment of the present invention. The transmission method can be used to improve the transmission throughput of the communication device 100, and includes the following steps performed by the communication device 100 (mainly the baseband signal processing circuit 130 / 200 therein):

[0069] Step S702: Receive packets.

[0070] Step S704: Parse the BSS color field in the received packet, the Length field in the PLCP header, and the Duration field in the MAC header to obtain their set contents.

[0071] Step S706: Determine whether the packet is from the OBSS. If yes, go to step S708. If no, go to step S712.

[0072] Step S708: Set the value of the parameter SR_Period to a first value within the duration of the transmission opportunity (ie, OBSS-TXOP) corresponding to the received packet, for example Figure 6 The bit values ​​shown have a high level.

[0073] Step S710: Determine whether the duration of the OBSS-TXOP has not ended according to the value of the parameter SR_Period, for example, determine whether the value of the parameter SR_Period is set to 1. If yes, execute step S714. If no, execute step S712.

[0074] Step S712: Wait for the duration of the TXOP of the received packet to end.

[0075] Step S714: Determine whether the queue for transmitting data has been determined. If yes, execute step S716. If no, execute step S718.

[0076] Step S716: Wait for SIFS.

[0077] Step S718: The back-off engine performs a countdown operation until one of them completes the countdown operation first. In the embodiment of the present invention, the back-off engine that completes the countdown operation first obtains the packet transmission opportunity within the entire OBSS-TXOP duration, and the response unit 221 finds the packet in the corresponding queue and transmits the packet according to the transmission power recommended by the transmission power control unit 222.

[0078] Step S720: Determine whether the duration of the OBSS-TXOP has not ended according to the value of the parameter SR_Period, for example, determine whether the value of the parameter SR_Period is set to 1. If yes, execute step S722. If no, execute step S724.

[0079] Step S722: Perform packet transmission in a spatial multiplexing manner.

[0080] Step S724: Perform packet transmission in a general manner.

[0081] It is worth noting that in the embodiment of the present invention, if there are packets to be transmitted temporarily stored in one or more queues, after determining that the received packet is a packet from the OBSS and the fallback engine corresponding to one of the queues competes for the opportunity to transmit the packet, within the duration of the OBSS-TXOP, the communication device 100 can directly transmit the packets temporarily stored in the queue in sequence in a spatial multiplexing manner. In contrast, if the received packet is not a packet from the OBSS, the communication device 100 must wait until the TXOP duration of the packet ends before performing packet transmission, and the packet transmission will be performed in a general manner.

[0082] In addition, it is worth noting that according to the second competition mechanism proposed by the present invention, after step S722 is completed, the process can return to step S710 to perform the judgment. If the judgment is still within the duration of the OBSS-TXOP, the judgment result of step S714 will be yes, so the fallback engine does not need to compete for the opportunity of packet transmission again, and directly continues to transmit the packets temporarily stored by the same queue after waiting for SIFS (step S716).

[0083] In an embodiment of the present invention, the value of the parameter SR_Period is set by obtaining the information of the OBSS-TXOP duration to indicate the status of the spatial multiplexing period. For example, if the value of the parameter SR_Period is set to 1, it means that it is still in the spatial multiplexing period, that is, the OBSS-TXOP duration has not ended. On the contrary, if the value of the parameter SR_Period is set to 0, it means that it is not in the spatial multiplexing period, that is, the OBSS-TXOP duration has ended. With this information, the transmission packet scheduling unit can flexibly arrange packet transmission, for example, according to the competition results of the aforementioned first competition mechanism or the second competition mechanism, arrange the packet to be transmitted in a spatial multiplexing manner, and transmit multiple packets in a spatial multiplexing manner within the OBSS-TXOP duration. In this way, the transmission throughput can be effectively improved and the delay can be reduced, so that the user experience is greatly improved.

[0084] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should fall within the scope of the present invention.

Claims

1. A communication device, include: A wireless transceiver circuit, configured to transmit and receive wireless signals, wherein the wireless signals include received packets; as well as A baseband signal processing circuit is coupled to the wireless transceiver circuit and is used to process the received packet, wherein the baseband signal processing circuit includes: A decision unit, configured to determine whether the received packet is from an overlapping basic service set, and determine the duration of the transmission opportunity according to information carried by the received packet; as well as A transmission packet scheduling unit, used to schedule the transmission of multiple packets, Wherein, when the decision unit determines that the received packet is from the overlapping basic service set, the transmission packet scheduling unit arranges the transmission of the first packet among the multiple packets within the duration of the transmission opportunity, and after the transmission of the first packet is completed, further determines whether the duration of the transmission opportunity has not ended, and when it is determined that the duration of the transmission opportunity has not ended, the transmission packet scheduling unit arranges the transmission of the second packet among the multiple packets within the duration of the transmission opportunity.

2. A communication device as described in claim 1, wherein when it is determined that the duration of the transmission opportunity has ended, the transmission packet scheduling unit arranges the transmission of a third packet among the multiple packets, wherein the transmission power of the third packet is different from the transmission power of the first packet and the transmission power of the second packet.

3. The communication device according to claim 1, wherein the baseband signal processing circuit further include: a memory unit for storing parameters, wherein the decision unit sets the value of the parameter to indicate the state during spatial multiplexing, and the transmission packet scheduling unit comprises: A plurality of queues, each queue being used to temporarily store a portion of the plurality of packets; a plurality of backoff engines, each backoff engine corresponding to one of the plurality of queues and configured to count a random backoff time; and A response unit is used for arranging the transmission of the first packet and arranging the transmission of the second packet according to a selected contention mechanism, and determining whether the duration of the transmission opportunity has not ended according to the value of the parameter stored in the memory unit.

4. A communication device as described in claim 3, wherein when the response unit determines that the duration of the transmission opportunity has not yet ended, the response unit determines to perform the transmission of the multiple packets in a spatial multiplexing manner, and when the selected competition mechanism is a first competition mechanism, the multiple backoff engines will respond to each packet transmission determined to be performed within the duration of the transmission opportunity to count the corresponding random backoff time, and when the selected competition mechanism is a second competition mechanism, the multiple backoff engines will only respond to the first packet transmission determined to be performed within the duration of the transmission opportunity to count the corresponding random backoff time.

5. A communication device as described in claim 4, wherein when the selected competition mechanism is the second competition mechanism, the first packet and the second packet are packets temporarily stored by the same queue, and the queue temporarily storing the first packet and the second packet is the queue corresponding to the backoff engine that first completes the counting of the random backoff time among the multiple backoff engines.

6. A communication device, include: A wireless transceiver circuit, configured to transmit and receive wireless signals, wherein the wireless signals include received packets; as well as a baseband signal processing circuit, coupled to the wireless transceiver circuit, configured to process the received packet, determine whether the received packet is from an overlapping basic service set, and determine the duration of the transmission opportunity according to information carried by the received packet, wherein when it is determined that the received packet is from the overlapping basic service set, the baseband signal processing circuit performs packet transmission in a spatial multiplexing manner during the duration of the transmission opportunity, and performs the packet transmission in a general manner after the duration of the transmission opportunity ends, and The transmission power used in the spatial multiplexing mode is different from the transmission power used in the general mode, and the baseband signal processing circuit transmits a plurality of packets in the spatial multiplexing mode within the duration of the transmission opportunity.

7. The communication device according to claim 6, wherein the baseband signal processing circuit include: a decision unit, configured to determine whether the received packet is from the overlapping basic service set, and determine the length of the duration of the transmission opportunity; as well as A transmission packet scheduling unit, used to schedule the transmission of multiple packets, The transmission packet scheduling unit arranges the transmission of the first packet among the multiple packets in the spatial multiplexing manner within the duration of the transmission opportunity, and after the transmission of the first packet is completed, further determines whether the duration of the transmission opportunity has not yet ended, and when it is determined that the duration of the transmission opportunity has not yet ended, the transmission packet scheduling unit arranges the transmission of the second packet among the multiple packets in the spatial multiplexing manner within the duration of the transmission opportunity.

8. The communication device according to claim 7, wherein when it is determined that the duration of the transmission opportunity has ended, the transmission packet scheduling unit arranges to transmit a third packet of the plurality of packets in the general manner.

9. The communication device according to claim 7, wherein the baseband signal processing circuit further include: a memory unit for storing parameters, wherein the decision unit sets the value of the parameter to indicate the state during spatial multiplexing, and the transmission packet scheduling unit comprises: A plurality of queues, each queue being used to temporarily store a portion of the plurality of packets; a plurality of backoff engines, each backoff engine corresponding to one of the plurality of queues and configured to count a random backoff time; and A response unit is used for arranging the transmission of the first packet and arranging the transmission of the second packet according to a selected contention mechanism, and determining whether the duration of the transmission opportunity has not ended according to the value of the parameter stored in the memory unit.

10. A communication device as described in claim 9, wherein when the response unit determines that the duration of the transmission opportunity has not yet ended, the response unit determines to perform the transmission of the multiple packets in the spatial multiplexing manner, and when the selected competition mechanism is a first competition mechanism, the multiple backoff engines will respond to each packet transmission determined to be performed within the duration of the transmission opportunity to count the corresponding random backoff time, and when the selected competition mechanism is a second competition mechanism, the multiple backoff engines will only respond to the first packet transmission determined to be performed within the duration of the transmission opportunity to count the corresponding random backoff time.

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