CN112584400B

CN112584400B - Method and apparatus for spatial reuse enhancement in a multi-station environment

Info

Publication number: CN112584400B
Application number: CN201910943963.8A
Authority: CN
Inventors: 刘佳宜
Original assignee: Realtek Semiconductor Corp
Current assignee: Realtek Semiconductor Corp
Priority date: 2019-09-30
Filing date: 2019-09-30
Publication date: 2023-08-25
Anticipated expiration: 2039-09-30
Also published as: CN112584400A

Abstract

The present invention provides a method and apparatus for spatial reuse enhancement in a multi-station environment. The method comprises the following steps: if the wireless communication device receives a receiving packet, checking the space reuse limit to perform first-stage space reuse judgment; if the spatial reuse limit meets the preset condition, triggering the transmission module to start the second-stage spatial reuse judgment; scanning at least one contention queue to obtain an index of a candidate station from the at least one contention queue; obtaining the latest information of the candidate station from an internal database of the wireless communication device based on the index, so as to calculate a threshold value special for the candidate station according to the latest information; and comparing an intensity index corresponding to the received packet with the threshold value to generate a comparison result, so as to control the triggering of the space reuse contention channel according to the comparison result.

Description

Method and apparatus for spatial reuse enhancement in a multi-station environment

Technical Field

The present invention relates to wireless communication systems, and more particularly, to a method and apparatus for Spatial Reuse (SR) enhancement in a multi-Station (STA) environment.

Background

According to the related art, one or more devices in a conventional wireless communication system may be spatially reused, which may cause some problems. For example, when a first device is transmitting a first wireless packet, a second device may attempt to spatially reuse (space reuse) the channel resources being used by the first wireless packet, particularly by transmitting a second wireless packet, such as a packet that is concurrent with and overlapping the channel or sub-channel being used by the first wireless packet. Due to lack of proper and robust judgment mechanism in the related art, erroneous operation may occur due to erroneous judgment, for example, the transmission power (transmitting power, TX power) of the second wireless packet may be too high or too low, so that the first wireless packet is interfered or the transmitted packet is not detected, which may cause redundant and unnecessary retransmission, thereby wasting bandwidth. As a result, the overall performance of conventional wireless communication systems is reduced. Accordingly, there is a need for a novel method and related architecture that improves the overall performance of a wireless communication system without or with less likelihood of side effects.

Disclosure of Invention

It is an object of the present invention to provide a method and apparatus for Spatial Reuse (SR) enhancement in a multi-Station (STA) environment to solve the above-mentioned problems.

It is another object of the present invention to provide a method and apparatus for spatial reuse enhancement in a multi-station environment to improve the overall performance of a wireless communication system without or with less likelihood of side effects.

At least one embodiment of the present invention provides a method for spatial reuse enhancement in a multi-station environment, wherein the method is applicable to an (applicable to) wireless communication device. The method may comprise: if the wireless communication device receives a reception packet (RX packet), checking the spatial reuse restriction to perform a first stage spatial reuse determination; if the spatial reuse limit meets a predetermined condition, triggering a transmission module (transmitting module, TX module) to start a second phase spatial reuse determination, wherein the transmission module is located in the wireless communication device; scanning at least one Contention Queue (Contention Queue) in the transmission module to obtain an index of a candidate station from the at least one Contention Queue, wherein the candidate station is selected from a plurality of stations in the multi-station environment; obtaining updated information of the candidate station from an internal database of the wireless communication device based on the index to calculate a threshold (threshold) specific to the candidate station based on the updated information of the candidate station; and comparing an intensity indicator (strength indicator) corresponding to the received packet with the threshold to generate a comparison result, so as to control triggering of a spatial reuse contention (SR Backoff) according to the comparison result.

At least one embodiment of the present invention provides an apparatus for spatial reuse enhancement in a multi-station environment, the apparatus being applicable to a wireless communication device, the apparatus comprising: at least one memory located in the wireless communication device for storing information to provide an internal database of the wireless communication device; and a medium access control (Media Access Control, MAC) circuit in the wireless communication device and coupled to the at least one memory for controlling operation of the wireless communication device. For example: if the wireless communication device receives a received packet, the medium access control circuit checks the spatial reuse restriction to make a first stage spatial reuse determination; if the spatial reuse restriction meets a preset condition, the media access control circuit triggers a transmission module to start to carry out second-stage spatial reuse judgment, wherein the transmission module is positioned in the media access control circuit; the medium access control circuit scans at least one contention queue in the transmission module to obtain an index of a candidate station from the at least one contention queue, wherein the candidate station is selected from a plurality of stations in the multi-station environment; the medium access control circuit obtaining the latest information of the candidate station from the internal database based on the index to calculate a threshold value specific to the candidate station according to the latest information of the candidate station; and the medium access control circuit compares an intensity index corresponding to the received packet) with the threshold value to generate a comparison result, so as to control the triggering of the space reuse contention channel according to the comparison result.

One of the benefits of the present invention is that by properly managing the information about each of the plurality of stations, the present invention can properly control the spatial reuse to effectively reduce the occurrence of signal interference or transmission failure, and in particular, can correspondingly reduce the probability of retransmission, and can greatly improve the overall performance of the wireless communication system under the condition of limited resources. Furthermore, implementation according to related embodiments of the present invention does not add much extra cost. Accordingly, the problems of the related art can be solved. Compared with the related art, the invention can achieve the optimal performance of the wireless communication system under the condition of no side effect or less possibility of bringing about the side effect.

Drawings

Fig. 1 is a schematic diagram of a wireless communication device according to an embodiment of the invention.

Fig. 2 illustrates the basic service set (Basic Service Set, BSS) and overlapping basic service set (Overlapping Basic Service Set, OBSS) involved in one embodiment of the wireless communication apparatus shown in fig. 1.

Fig. 3 is a flow chart of a method for Spatial Reuse (SR) enhancement in a multi-Station (STA) environment in accordance with an embodiment of the present invention.

FIG. 4 is a control scheme of the method of FIG. 3 according to an embodiment of the present invention.

Detailed Description

Fig. 1 is a schematic diagram of a wireless communication device 100 according to an embodiment of the invention. The wireless communication device 100 may include at least one memory (e.g., one or more memories) such as a memory 110, a medium access control (Media Access Control, MAC) circuit 120, a baseband module 130, and a radio frequency module 140. Memory 110 may include an internal database 112, and internal database 112 may include at least one station information table (e.g., one or more station information tables), such as station information table 114. The medium access control circuit 120 may include a receiving module 120RX and a transmitting module 120TX, wherein the receiving module 120RX may include a Spatial Reuse (SR) control circuit 121 and one or more other circuits, and the transmitting module 120TX may include a Contention control circuit 120C, which may include a Queue Candidate control circuit 122, a threshold estimation (Threshold Estimation) circuit 124, a Spatial Reuse Contention control circuit 126 and a transmission control circuit 128. The above-listed components may be coupled to each other as shown in fig. 1, but the present invention is not limited thereto. For example, one or more additional components may be added to the architecture shown in FIG. 1, and/or the manner of connection between certain components may vary. In addition, the spatial reuse control circuit 121 may be coupled to a receiving path in the wireless communication device 100, and the contention control circuit 120C (e.g., the queue candidate control circuit 122, the threshold estimation circuit 124, the SR contention control circuit 126, and the transmission control circuit 128) may be coupled to a transmitting path in the wireless communication device 100, wherein the receiving path and the transmitting path are respectively formed by a group of components (e.g., a Low noise Amplifier (Low Noise Amplifier, LNA), a Mixer, an automatic gain control (Automatic Gain Control, AGC), and an Analog-to-Digital Converter, ADC)) and another group of components (e.g., a Digital-to-Analog Converter (DAC), a Low Pass Filter (LPF), a Mixer, a Power Amplifier (PA)), in the rf module 140, but the invention is not limited thereto. The at least one memory, such as the memory 110, may be used to store information for use by the internal database 112, the medium access control circuit 120 may be used to control the operation of the wireless communication device 100, the baseband module 130 may be used to perform baseband processing, and the rf module 140 may be used to perform rf processing to allow the wireless communication device 100 to receive or transmit packets via the antenna.

Based on the architecture shown in fig. 1, the wireless communication device 100 may perform spatial reuse, and in particular, perform related operations in accordance with institute of electrical and electronics engineers (Institute of Electrical and Electronics Engineers, IEEE) 802.11AX specifications, and build and update an internal database 112 (e.g., the above-mentioned at least one station information table such as the station information table 114) to have respective various information of at least a part of devices (e.g., a part or all of devices) among various wireless communication devices in the environment, such as a plurality of group information STA info (1), STA (2), … and STA (X) corresponding to the plurality of stations STA (1), STA info (2), … and STA info (X), respectively, to properly and accurately perform related determination, wherein the wireless communication device 100 may update the plurality of group information STA info (1), STA info (2), … and STA info (X) into respective latest information of the plurality of stations STA (1), STA (2), … and STA (X), but the invention is not limited thereto. For example, when another wireless communication device is transmitting a first wireless packet, the wireless communication device 100 may attempt to spatially reuse the resources being used by the first wireless packet, particularly by transmitting a second wireless packet, such as a packet that is concurrent with and overlapping the channel or sub-channel being used by the first wireless packet. Since the wireless communication device 100 has a proper and robust judgment mechanism, the present invention can avoid problems of the related art, such as erroneous operation caused by erroneous judgment.

In accordance with certain embodiments, an apparatus for Spatial Reuse (SR) enhancement in a multi-Station (STA) environment may include at least a portion (e.g., a portion or all) of a wireless communication device 100. For example, the apparatus may comprise a processing circuit of the wireless communication device 100, which may comprise the memory 110 and the medium access control circuit 120, and in particular, may further comprise the baseband module 130 and the radio frequency module 140, wherein the processing circuit may be implemented as one or more integrated circuits or as a chipset. For another example, the apparatus may comprise the entirety of the wireless communication device 100.

Fig. 2 illustrates a basic service set (Basic Service Set, BSS) and an overlapping basic service set (Overlapping Basic Service Set, OBSS) related to the wireless communication apparatus 100 shown in fig. 1 in an embodiment. As shown in fig. 2, the BSS and the OBSS may include wireless communication devices { ap_1, sta_1, sta_2, sta_3, … } and { o_ap_1, o_sta_1, o_sta_2, o_sta_3, … } respectively, wherein the wireless communication devices ap_1 and o_ap_1 may be implemented as Access Points (APs) and the wireless communication devices { sta_1, sta_2, sta_3, … } and { o_sta_1, o_sta_2, o_sta_3, … } may be implemented as stations (stations, STAs). The wireless communication device ap_1 may be used as an example of the wireless communication device 100, and at least a part of other devices (e.g., a part or all of the other devices) such as the wireless communication devices { sta_1, sta_2, sta_3, … } and { o_sta_1, o_sta_2, o_sta_3, … } may be used as examples of the at least a part of the devices, but the present invention is not limited thereto.

Fig. 3 is a flow chart of a method for spatial reuse enhancement in a multi-station environment according to an embodiment of the present invention. The method is applicable to (appable to) wireless communication device 100, and in particular, the architecture shown in fig. 1 (e.g., memory 110, medium access control circuit 120, etc.), and may be performed by the apparatus.

In step S10, the medium access control circuit 120 (e.g., the spatial reuse control circuit 121) may determine whether the wireless communication device 100 receives a reception packet (RX packet) rx_pkt. If yes, go to step S12; if not, the process advances to step S10. For example, the wireless communication device 100 may receive the received packet rx_pkt through the receive path.

In step S12, the medium access control circuit 120 (e.g., the spatial reuse control circuit 121) may check the spatial reuse restriction to perform the first stage spatial reuse determination.

In step S14, the medium access control circuit 120 (e.g., the spatial reuse control circuit 121) may determine whether the spatial reuse restriction meets a predetermined condition. If yes, go to step S16; if not, the process advances to step S10. For example, the spatial reuse restriction meeting the predetermined condition may include receiving packets rx_pkt belonging to a predetermined type of packet, and the operation of checking the spatial reuse restriction may include checking whether the receiving packets rx_pkt belong to the predetermined type of packet, but the present invention is not limited thereto. In some embodiments, the wireless communication device 100 may belong to the BSS, and the predetermined type of packet may represent a packet belonging to the OBSS, such as a packet sent by a certain wireless communication device in the OBSS, but the invention is not limited thereto.

In step S16, the medium access control circuit 120 (e.g. the spatial reuse control circuit 121) may store a received packet power level (power level) RPL of the received packet rx_pkt, and trigger the transmission module 120TX to start the second stage spatial reuse determination, and in particular, transmit the received packet power level RPL to the transmission module 120TX (e.g. the queue candidate control circuit 122) for further use. In addition, when the transmission module 120TX starts to perform the second stage spatial reuse determination, the medium access control circuit 120 (e.g., the contention control circuit 120C) may set a cyclic index i to an initial value such as 0.

In step S18, the medium access control circuit 120 (e.g., the Queue candidate control circuit 122) may scan at least one contention Queue (e.g., one or more contention queues) in the transmission module 120TX, such as the Queue (i) of the (i_max+1) queues { Queue (0), …, queue (i_max) }, to obtain an index STA id (x (i)) of a candidate station STA (x (i)) from the at least one contention Queue such as the Queue (i), wherein i_max may be a positive integer, but the invention is not limited thereto. For example, the Queue candidate control circuitry 122 may include the at least one competing Queue such as the (i_max+1) queues { Queue (0), …, queue (i_max) }. In addition, the candidate station STA (X (i)) may be selected from the plurality of stations STA (1), STA (2), … and STA (X), and the index STA id (X (i)) is queued in the at least one contention Queue such as Queue (i) to indicate that a transmission packet tx_pkt (X (i)) corresponding to the candidate station STA (X (i)) is waiting to be transmitted to the candidate station STA (X (i)).

In step S20, the medium access control circuit 120 (e.g., the threshold estimation circuit 124) may obtain the latest information starfo (x (i)) of the candidate station STA (x (i)) from the internal database 112 based on the index stard (x (i)) to calculate a threshold (threshold) obss_pd_th (x (i)) dedicated to the candidate station STA (x (i)) according to the latest information starfo (x (i)) of the candidate station STA (x (i)). For example, the medium access control circuit 120 (e.g., the threshold estimation circuit 124) may query the at least one station information table, such as the station information table 114, according to the index STA id (x (i)) to obtain the latest information STA info (x (i)) of the candidate station STA (x (i)).

In step S22, the medium access control circuit 120 (e.g., the contention control circuit 120C) may determine whether i < i_max. If yes, go to step S24; if not, the process advances to step S26.

In step S24, the medium access control circuit 120 (e.g., the contention control circuit 120C) increases the cyclic index i (labeled "i++" in fig. 3 for simplicity) by an increment such as 1.

In step S26, the medium access control circuit 120 (e.g. the threshold estimation circuit 124) may calculate an intensity index (strength indicator) s_ind corresponding to the received packet rx_pkt, for example:

S_ind＝RPL-OBSS_PDmin；

wherein the strength indicator s_ind represents a difference (RPL-obss_pdmin) obtained by subtracting a predetermined value, such as the parameter obss_pdmin, from the received packet power level RPL of the received packet rx_pkt. For details regarding the parameter obss_pdmin, please refer to the IEEE 802.11AX specification. In addition, the medium access control circuit 120 (e.g., the contention control circuit 120C) may set a round index j to an initial value such as 0.

In step S28, the medium access control circuit 120 (e.g., the threshold estimation circuit 124) may determine whether s_ind < obss_pd_th (x (j)). If yes, go to step S30; if not, the process advances to step S32.

In step S30, the medium access control circuit 120 (e.g., the threshold estimation circuit 124) may trigger an SR contention for the transmission packet tx_pkt (x (j)). The SR contention control circuit 126 may then perform the SR contention with respect to the transmit packet tx_pkt (x (j)), and in particular, generate a random number and count down based on the random number to await spatial reuse, e.g., trigger the transmit control circuit 128 to perform transmit control to transmit the transmit packet tx_pkt (x (j)) to the candidate station STA (x (j)) through the transmit path and corresponding antenna without any other wireless communication device performing spatial reuse until the count down ends.

According to the present embodiment, the medium access control circuit 120 (e.g., the threshold estimation circuit 124) may compare the strength indicator s_ind corresponding to the received packet rx_pkt with the threshold obss_pd_th (x (j)) in step S28 to generate a comparison result (which may indicate whether s_ind < obss_pd_th (x (j)) or not) so as to control the triggering of the SR contention with respect to the transmitted packet tx_pkt (x (j)) according to the comparison result.

In step S32, the medium access control circuit 120 (e.g., the contention control circuit 120C) may determine whether j < j_max. If yes, go to step S34; if not, the process advances to step S10. For example, j_max=i_max.

In step S34, the medium access control circuit 120 (e.g., the contention control circuit 120C) increases the cyclic index j (labeled "j++" in fig. 3 for simplicity) by an increment such as 1.

For better understanding, the method may be illustrated with the workflow shown in fig. 3, but the invention is not limited thereto. According to some embodiments, one or more steps may be added, deleted, or modified in the workflow shown in FIG. 3. For example, the calculation of the strength indicator s_ind in step S26 may be integrated into step S28, and in particular, in step S28, the medium access control circuit 120 (e.g., the threshold estimation circuit 124) may determine whether (RPL-obss_pdmin) < obss_pd_th (x (j)). For another example, the calculation of the intensity index S_ind in step S26 may be integrated into step S28, as described above, and the loop including steps S18-S24 and the loop including steps S28-S34 may be integrated into the same loop, which uses the same loop index i; and the sub-processes of steps S28 to S30 may be interposed between steps S20 and S22, and the loop index j in steps S28 to S30 may be replaced with the loop index i, wherein the determination result "no" of step S28 is directed to step S22, and the determination result "no" of step S22 is directed to step S10. For brevity, descriptions of embodiments similar to the previous embodiments are not repeated here.

According to some embodiments, the contention control circuit 120C in the transmission module 120TX may include a control logic circuit for controlling the loop including steps S18-S24 and/or the loop including steps S28-S34 (e.g., the loop including steps S18-S24 and the loop including steps S28-S34), but the invention is not limited thereto.

According to some embodiments, when the other wireless communication device is transmitting the first wireless packet, such as the reception packet rx_pkt, the wireless communication device 100 may attempt to perform spatial reuse, particularly, by transmitting the second wireless packet, such as a transmission packet tx_pkt (e.g., the transmission packet tx_pkt (x (j)) as described in step S30. To prevent the influence on the reception packet rx_pkt that is originally being transmitted, the wireless communication device 100 (e.g., the medium access control circuit 120, particularly, the transmission module 120TX therein) may properly adjust the transmission power (TX power) of the transmission packet tx_pkt. For example, the medium access control circuit 120 (e.g., the Threshold estimation circuit 124) may calculate a corresponding Threshold value obss_pd_threshold (e.g., the Threshold value obss_pd_th (x (i)) as described in step S20) according to the following equation:

OBSS_PD_Threshold＝TXPWRref-f((TXPWR-POWER_TOLERANCE-PWR_Offset))；

where TXPWRREF may represent a default hardware-defined POWER reference value, TXPWR may represent a transmit POWER value corresponding to a predetermined Data Rate (Data Rate), POWER_TOLERANCE may represent a POWER TOLERANCE range, PWR_Offset may represent a POWER Offset value corresponding to the predetermined Data Rate, and f () may represent a transfer function for converting the POWER value to a transmit packet POWER level, but the invention is not limited thereto. For another example, the medium access control circuit 120 need not convert certain parameters related to power to a power level, and the medium access control circuit 120 (e.g., the Threshold estimation circuit 124) may calculate the corresponding Threshold obss_pd_threshold according to the following equation:

OBSS_PD_Threshold＝TXPWRref-(TXPWR-POWER_TOLERANCE-PWR_Offset)；

but the present invention is not limited thereto.

Furthermore, the corresponding Threshold obss_pd_threshold described above may represent, from some points of view: during the spatial reuse, the transmission power of the allowed transmit packet tx_pkt is reduced by a maximum value (or threshold). A wireless communication device 100 implemented in accordance with one or more embodiments of the invention, such as medium access control circuitry 120, and in particular threshold estimation circuitry 124 therein, may calculate a threshold value specific to each candidate station, such as a threshold value OBSS PD Th (x (i)) specific to a candidate station STA (x (i)) for the candidate station STA (x (i)). Compared with the related art, the invention can more effectively control the triggering of the SR contention channel.

According to some embodiments, for any station STA (X) among the stations STA (1), STA (2), … and STA (X), the X-th group information STA info (X) among the group information STA info (1), STA info (2), … and STA info (X) may include a transmission POWER value TXPWR (X) of the transmission packet tx_pkt (X), a POWER TOLERANCE range power_header (X), a POWER Offset value pwr_offset (X), an estimated DISTANCE est_distance (X), a medium access control address mac_add (X), etc., wherein the symbol "X" may represent an integer in the interval [1, X ], but the present invention is not limited thereto. For brevity, descriptions of embodiments similar to the previous embodiments are not repeated here.

FIG. 4 is a control scheme of the method of FIG. 3 according to one embodiment of the present invention. The Queue Candidate control circuit 122 may include a set of sub-circuits queue_candida_vo, queue_candida_vi, queue_candida_be, and queue_candida_bk corresponding to the set of packet types VO, VI, BE, and BK, respectively, the THRESHOLD estimation circuit 124 may include a set of sub-circuits obss_pd_threshold_vo, obss_pd_threshold_vi, obss_pd_threshold_be, obss_pd_be, and obss_pd_threshold_bk corresponding to the set of packet types VO, VI, BE, and BK, respectively, and the SR contention control circuit 126 may include a set of sub-circuits sr_koff_vi, sr_bacff_be, and sr_bacff_bk corresponding to the set of packet types VO, VI, BE, and BK, respectively, wherein the set of VO, VI, BE, and BK may have priorities corresponding to one of the three sub-circuits of the three priority levels, respectively, but may not have priorities. For example, the set of packet types VO, VI, BE, and BK may represent Voice (Voice), video (Video), best effort (Best effort), and Background (Background), respectively, and may have the highest priority, the second highest priority, the third highest priority, and the lowest priority, respectively.

According to this embodiment, the Queue candidate control circuit 122 may include four queues Queue (0), queue (1), queue (2), and Queue (3) (e.g., i_max=3), which may be respectively queued with the indexes { STAid (1), … }, { STAid (5), … }, { STAid (3), … } and { STAid (4), … }. After the loop including steps S18-S24 is completed, the medium access control circuit 120 (e.g. the queue candidate control circuit 122) may obtain the indexes STAid (1), STAid (5), STAid (3) and STAid (4), and the medium access control circuit 120 (e.g. the threshold estimation circuit 124) may obtain their latest information based on the indexes and calculate the thresholds obss_pd_th (1), obss_pd_th (5), obss_pd_th (3) and obss_pd_th (4), wherein x (0) =1, x (1) =5, x (2) =3, and x (3) =4. For ease of understanding, assume obss_pd_th (1) =8, obss_pd_th (5) =3, obss_pd_th (3) =10, obss_pd_th (4) =9, and s_ind=5, wherein examples of values of these parameters may indicate their respective power levels, but the invention is not limited thereto. After the loop including steps S28-S34 is completed, the medium access control circuit 120 (e.g., the threshold estimation circuit 124) has triggered the SR contention for the transmission packets tx_pkt (1), tx_pkt (3) and tx_pkt (4), but not the transmission packet tx_pkt (5), so that the set of sub-circuits sr_backoff_vo, sr_backoff_vi, sr_backoff_be and sr_backoff_bk in the SR contention control circuit 126 have corresponding SR contention enable/disable states, respectively. For example, the sub-circuits SR_BACKFF_VO, SR_BACKFF_BE and SR_BACKFF_BK all have SR contention enabling state SR_BKF_EN, and the sub-circuit SR_BACKFF_VI has SR contention disabling state SR_BKF_STOP. For brevity, descriptions of the embodiments similar to the foregoing embodiments will not be repeated here.

The foregoing description is only of the preferred embodiments of the invention, and all changes and modifications that come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

[ symbolic description ]

100、AP_1、STA_1、STA_2、

STA_3…、O_AP_1、O_STA_1、

O_STA_2, O_STA_ … wireless communication device

110. Memory

112. Internal database

114. Station information table

120. Medium access control circuit

120C competition control circuit

120RX receiving module

120TX transmission module

121. Spatial reuse control circuit

122. Queue candidate control circuit

124. Threshold value estimating circuit

126 SR contention control circuit

128. Transmission control circuit

130. Fundamental frequency module

140. Radio frequency module

STAid (1), STAid (2), … STAid (X) index

STAinfo(1)、STAinfo(2)、…

STAinfo (X) information

S10、S12、S14、S16、S18、

S20、S22、S24、S26、S28、

S30, S32 and S34 steps

Queue_Candidate_VO、

Queue_Candidate_VI、

Queue_Candidate_BE、

Queue_Candidate_BK、

OBSS_PD_THRESHOLD_VO、

OBSS_PD_THRESHOLD_VI、

OBSS_PD_THRESHOLD_BE、

OBSS_PD_THRESHOLD_BK、

SR_BACKOFF_VO、

SR_BACKOFF_VI、

SR_BACKOFF_BE、

SR_BACKFF_BK sub-circuit

Queue(0)、Queue(1)、

Queue (2) and Queue (3)

STAid (3), STAid (4), STAid (5) index

OBSS_PD_Th(1)、…

OBSS_PD_Th(3)、

OBSS_PD_Th(4)、

Obss_pd_th (5) … threshold

SR_BKF_EN SR contention enabling state

Sr_bkf_stop SR contend for the lane disabled state.

Claims

1. A method for spatial reuse enhancement in a multi-station environment, applicable to a wireless communication device, the method comprising:

if the wireless communication device receives a receiving packet, checking the space reuse limit to perform first-stage space reuse judgment;

if the spatial reuse limit meets a preset condition, triggering a transmission module to start to carry out second-stage spatial reuse judgment, wherein the transmission module is positioned in the wireless communication device;

scanning at least one contention queue in the transmission module to obtain an index of a candidate station from the at least one contention queue, wherein the candidate station is selected from a plurality of stations in the multi-station environment;

obtaining the latest information of the candidate station from an internal database of the wireless communication device based on the index, so as to calculate a threshold value specific to the candidate station according to the latest information of the candidate station; and

a strength indicator corresponding to the received packet is compared with the threshold to generate a comparison result, and the triggering of the spatial reuse contention is controlled according to the comparison result.

2. The method of claim 1, wherein the meeting of the spatial reuse restriction to the predetermined condition includes the received packet belonging to a predetermined type of packet; and the step of checking the spatial reuse restriction comprises:

checking whether the received packet belongs to the predetermined type of packet.

3. The method of claim 2 wherein the wireless communication device belongs to a basic service set and the predetermined type of packet represents packets belonging to an overlapping basic service set.

4. The method of claim 1 wherein the index is queued in the at least one contention queue to indicate that a transmit packet corresponding to the candidate station is waiting to be transmitted to the candidate station.

5. The method of claim 1, wherein the internal database comprises at least one station information table, wherein the at least one station information table comprises a plurality of sets of information corresponding to the plurality of stations, respectively, and a set of information corresponding to the candidate station among the plurality of sets of information comprises the most current information of the candidate station; and retrieving the most current information for the candidate station from the internal database based on the index comprises:

and inquiring at least one station information table in the wireless communication device according to the index so as to acquire the latest information of the candidate station.

6. The method of claim 1 wherein the strength indicator represents a difference of a received packet power level of the received packet subtracted by a predetermined value.

7. The method of claim 1, wherein the comparison indicates whether the intensity indicator is less than the threshold; and controlling the triggering of the spatial reuse contention based on the comparison result comprises:

if the comparison indicates that the strength indicator is less than the threshold, triggering the spatial reuse contention.

8. The method of claim 1 wherein the index is queued in the at least one contention queue to indicate that a transmit packet corresponding to the candidate station is waiting to be transmitted to the candidate station; for controlling the triggering of the spatial reuse contention based on the comparison result, the spatial reuse contention representing a spatial reuse contention for the transmitted packet; the method comprises the following steps:

scanning the at least one contention queue to obtain another index of another candidate station from the at least one contention queue, wherein the another candidate station is selected from the plurality of stations, and the another index is queued in the at least one contention queue to indicate that another transmission packet corresponding to the another candidate station is waiting to be transmitted to the another candidate station;

retrieving from the internal database, based on the further index, up-to-date information of the further candidate station to calculate a further threshold value specific to the further candidate station in dependence on the up-to-date information of the further candidate station; and

comparing the strength indicator corresponding to the received packet with the other threshold to generate another comparison result, and controlling triggering of the spatial reuse contention for the other transmission packet according to the other comparison result.

9. An apparatus for spatial reuse enhancement in a multi-station environment, applicable to a wireless communication device, the apparatus comprising:

at least one memory located in the wireless communication device for storing information to provide an internal database of the wireless communication device; and

a medium access control circuit in the wireless communication device and coupled to the at least one memory for controlling the operation of the wireless communication device, wherein:

if the wireless communication device receives a received packet, the medium access control circuit checks the spatial reuse restriction to make a first stage spatial reuse determination;

if the spatial reuse restriction meets a preset condition, the media access control circuit triggers a transmission module to start to carry out second-stage spatial reuse judgment, wherein the transmission module is positioned in the media access control circuit;

the medium access control circuit scans at least one contention queue in the transmission module to obtain an index of a candidate station from the at least one contention queue, wherein the candidate station is selected from a plurality of stations in the multi-station environment;

the medium access control circuit obtains the latest information of the candidate station from the internal database based on the index to calculate a threshold value specific to the candidate station according to the latest information of the candidate station; and

the medium access control circuit compares an intensity index corresponding to the received packet with the threshold value to generate a comparison result, and controls triggering of the space reuse contention channel according to the comparison result.

10. The apparatus of claim 9, wherein the medium access control circuit comprises:

a receiving module, comprising:

a spatial reuse control circuit, coupled to a receiving path in the wireless communication device, for performing operations of checking the spatial reuse restriction to perform the first stage spatial reuse determination and triggering the transmission module to start the second stage spatial reuse determination; and

the transmission module comprises:

a queue candidate control circuit, coupled to the spatial reuse control circuit, for performing an operation of scanning the at least one contention queue to obtain the index of the candidate station from the at least one contention queue, wherein the queue candidate control circuit comprises the at least one contention queue;

a threshold value estimating circuit, coupled to the queue candidate control circuit, for performing operations of obtaining the latest information of the candidate station from the internal database based on the index to calculate the threshold value specific to the candidate station according to the latest information of the candidate station, and comparing the intensity index corresponding to the received packet with the threshold value to generate the comparison result to control the triggering of the spatial reuse contention channel according to the comparison result; and

a spatial reuse contention control circuit, coupled to the threshold estimation circuit and a transmission path in the wireless communication device, for performing the spatial reuse contention.