TWI383619B - Method and apparatus for signaling deferral management messages - Google Patents

Description

Method and device for sending delayed management information

The present invention relates to a wireless local area network (WLAN), and more particularly, the present invention relates to performing a deferred management information policy among WLANs.

A wireless local area network (WLAN), such as, but not limited to, an IEEE 802 WLAN, uses a carrier-sense multiple access/ Collision avoidance, CSMA/CA) planning to share a wireless medium between wireless acknowledgments (WTRUs) (ie, mobile stations (STAs)) , WM), and this plan will force the WTRUs to sense whether the WM is idle or busy before transmitting a packet, and this is to use a clear channel assessment (CCA) function. And to perform, if a WTRU senses that the channel is busy (hereinafter, a WTRU hears another transmission), the WTRU cannot transmit its packet, and is trying to win the Before the channel competes, the system must wait until the signal is idle. This is called delay, and by avoiding two simultaneous WTRUs listening to each other, the CSMA/CA plan can be used in the system. The level of control interference.

In a WLAN, a low-order interference system indirectly improves the system's capabilities, just as the amount of traffic achieved on each radio link. (throughput) will increase as the interference is reduced. In other words, in order to avoid the simultaneous transmission of the two nodes that can be heard by each other on the same channel, the cost is due to the lack of spectrum channel resources that cannot be reused. This will result in limited capacity in systems where multiple base station systems (BSSs) use the same channel.

In a CSMA/CA system, whether a first WTRU is to listen to a second WTRU's decision (here, the second WTRU is located above a given path from the first WTRU) depends on two factors (1) the transmission power used by the first WTRU; and (2) the reception/delay threshold used by the second WTRU, so by controlling one or both of these factors, It is possible to control the degree of delay in a WLAN, and therefore, the ability. Two key receive/delay thresholds can be used among the CCA functions of the WTRUs operating in CSMA/CA, which are: (1) energy detect threshold (EDT), It represents the minimum received signal power of a packet attempting to receive, and (2) the deferred threshold (DT), which represents the minimum received signal power that a packet will be delayed by the transmission of the WTRU. .

In summary, sometimes, a better view would be to reduce the transmission power and/or the DT/EDT capability of the WTRUs in co-channel BBSs, and therefore, from among the BSSs. One of the WTRUs does not listen to the other of the BSSs, and vice versa, however, if the delay parameter adjustment is made without considering the effect of this adjustment on other WTRUs, When executed at each WTRU, there is a possibility that a problem arises. For example, if a WTRU excessively reduces its transmission power, it will become unpaired for other WTRUs in the same BSS. It is possible that the signal is detected from the WTRU through the EDT, or DT, and a hidden node may be generated, and a hidden node phenomenon across the BSSs may occur, so that it is optimal. Proper operation, coordination between the WTRUs is required to enable collection of all required information at the node that determines the settings of the delay parameters, and the node may be the WTRU itself, or Is the WTR An access point (AP) associated with U, in the latter case, coordination may also be required to enable the AP to communicate with the WTRU(s) of interest. The value of the good delay parameter.

The present invention relates to a delay management method that is implemented in a WLAN including an AP and a plurality of WTRUs. The AP sends a deferred management capability request message to the WTRUs to determine the delay management capabilities of the WTRUs, such as maximum transmission rate, minimum transmission and/or dynamic range, minimum and maximum DT/EDT, and The CCA mode, and then, in response, each of the WTRUs sends a deferred management capability parameter setting information to the AP, and then the AP system can also send a deferred management parameter setting information to the WTRUs to Indicates the value used to set the deferred management parameters, and includes the information destination identification, the construction time limit, and the transmission power setting. Further, in response, each of the WTRUs can selectively send a delay. The management parameter settings perform confirmation information to the AP, and in an alternative embodiment, the WTRUs may also set various delays according to a specific rule contained in one of the delay management rule information sent by the AP. Managing the values of the parameters, and optionally, the WTRUs are capable of including such deferred management parameters as a result of executing the rules The real-value deferred management rule executes the confirmation information and returns to the AP.

The present invention relates to a wireless system using a CSMA/CA scheme, such as, for example, but not limited to, the IEEE 802 family of standards, wherein delaying management measurements is in a coordinated manner between all WTRUs Execution, while in medium and relatively large wireless systems, the deferred management strategy can increase the system's capabilities by more than 500%. Here, a specific example to which the present invention is applied falls within the scope of the IEEE 802.11v standard.

The present invention provides a mechanism for enabling such WTRUs of a BSS to set their deferred management parameters using a coordinated approach, which will ultimately result in the deferred management policy being able to fully utilize the potential increase in capabilities that they can provide.

Although the features and elements of the present invention are described in terms of a preferred combination of specific embodiments, each feature or element can be used separately (in the case where other features and elements of the preferred embodiment are not required) B) used, or in combination with or without other features and elements of the invention.

As mentioned later, the proper noun "WTRU" includes, but is not limited to, a user equipment (UE), a mobile station, a fixed, or mobile subscriber unit, a pager, or any capable of Other types of devices operating in a wireless environment, and as mentioned later, the proper noun "AP" includes, but is not limited to, a Node B, a position controller, or can be interfaced in a wireless environment. Any other type of device.

The present invention provides two preferred embodiments for performing deferred management. In a first embodiment, an AP will communicate directly with at least one of its associated WTRUs that the WTRUs should set their deferred management parameters, and in the second embodiment, an AP Then, at least one of the WTRUs associated with it is communicated with the rules for calculating and setting the deferred management parameters they have.

In order for the WTRUs' delay management parameters to be controlled by an AP on a different basis, there are two preferred signaling procedures. The first signaling program enables the AP to indicate to the at least one WTRU the delay parameters that the at least one WTRU should use, and the second signaling procedure is to enable the AP to collect from at least one WTRU A measure of the decision of the delay parameters that at least one WTRU should use.

1 is a flow diagram of the first signaling program executed in a wireless communication system (eg, WLAN) 100, and wherein the wireless communication system includes an AP 105 and a plurality of WTRUs 110 ₁ -110 _N . The AP 105 system sends a deferred management capability request message 115 to a WTRU or a plurality of WTRUs to report its deferred management capability, and the deferred management capability request information 115 can be used as a broadcast, multicast, or The unicast signal is transmitted, and the delay management capability includes the following parameters: 1) maximum transmit power, minimum transmit power, and/or dynamic range of the WTRU; 2) minimum DT/ WTRU that the WTRU can use. EDT and maximum DT/EDT; and 3) different CCA (Clear Channel Assessment) modes supported by the WTRU.

A deferred management capability indicator information 120 can be transmitted by the (etc.) WTRU(s) 10 as a response to the deferred management capability request information 115 sent by the AP 105, and the deferred management capability The indicator information 120 is another one of the association/admission control procedures that can be attached to such a related request information or linked to a license to manage the WTRU 110 in the WLAN 100. message.

A deferred management parameter setting information 125 is sent from the AP 105 to one or more of the WTRUs 110, and the deferred management parameter setting information 125 indicates which values are for deferring management parameters. The setting is performed, wherein the deferred management parameter setting information 125 can be transmitted as a broadcast, multicast, or unicast signal, and preferably includes the following information: 1) for the information The identification of the WTRU's destination is provided, and preferably, the identification will be a medium access control (MAC) address, although any other type of WTRU destination may be used. Identifier.

2) one of the WTRUs delays the management parameter from the point in time at which the construction of the management parameter setting information is required to be performed, or, alternatively, the deferred management parameter setting information 125 may indicate that the need is The time limit for the construction. The time information can be expressed as a time offset or an absolute form.

3) The delay management parameters and the values that the WTRU needs to use. Examples of such parameters are: a) Transmission power settings during normal operation.

b) Transmission power setting in special operations, wherein examples of special operations include, but are not limited to, scanning operations and measurement collection.

c) DT/EDT settings during normal operation.

d) DT/EDT settings in special operations, where examples of special operations include, but are not limited to, scanning operations and measurement collection.

e) (multiple) CCA mode.

As shown in FIG. 1, a deferred management parameter setting execution confirmation message 130 can be selectively transmitted by the (etc.) WTRU(s) 110 to acknowledge to the AP 105, for a given The construction system indicated in the deferred management parameter setting information 125 has been held, and the selective deferred management parameter setting execution confirmation information 130 is any such content that may be included in the deferred management parameter setting information. The parameter may be a transition indicator that associates the deferred management parameter setting execution confirmation information 130 with the corresponding deferred management parameter setting information 125, and the deferred management parameter setting execution confirmation information 130 indicates the deferred management. The reason for this is to enable the AP 105 to report the real parameters set according to the deferred management parameter setting information 125. For example, if the AP 105 commands the WTRU 110 to set its transmit power to 0 dBm and its EDT is set to -75 dBm, then it is likely that the WTRU 110 will reduce its EDT to -75 dBm. The power is also reduced, but cannot be reduced to less than 13 dBm. In such an example, the WTRU 110 may send a deferred management parameter setting execution confirmation message 130 to indicate that the delay may be provided by The real settings of the construction achieved by the information in the same type of information found in the information parameter setting information 125.

2 is a flow diagram of the second signaling program executed in a wireless communication system 200, and wherein the wireless communication system 200 includes an AP 205 and a plurality of WTRUs 210 _{1 -} 210 _N . The second signaling program enables the AP 205 to collect measurements from the WTRU(s) 210 relating to the delay parameters that the WTRU(s) 210 should use, and related measurements may include, but are not limited to, : 1) The signal strength (or average) of packets received by a WTRU from other special WTRUs.

2) The number of packets received by a WTRU from other specific WTRUs and the overall duration.

The signaling program may compensate for such deferred management parameters that are optimal in terms of availability during normal operation, which may not be optimal during the scanning period, for example, during the scanning period. For example, in a particular case where a given WTRU 210 is required to increase its DT/EDT during normal operation, a high DT/EDT may be due to the accurate measurement of certain metrics, such as channels. Occupy, derogating from the WTRU 210's capabilities, so to avoid such a impairment, the AP 205 will indicate, as part of a measurement requirement, which delay management parameters are used by a WTRU when collecting measurements. of.

As shown in FIG. 2, a measurement request message 215 is sent to the WTRU(s) 210 by the AP 205, and it indicates which type of WTRUs 210 are to be executed. The measurement of the state, and the deferred management parameters (eg, DT/EDT, CCA mode, or the like) should be used in collecting the requested measurements, and then a measurement report information 220 will be used by the WTRUs. (s) 210 is sent to the AP 205 to indicate the results of the measurement and which delay management parameters (eg, DT/EDT, CCA mode, or the like) are correctly used to collect the reported Measurements, wherein the information 215 and 220 may be used separately or together, and further, the delay management parameters used during the measurement may be different from those required by the AP 205 in the measurement request information 215. Those using the WTRUs 210 associated with them, the AP 205 can perform calculations and determine the optimal delay parameters for each of the WTRUs 210, for example, a possible policy. Yes, will be a given WTRU 210 The EDT is set to the minimum signal strength (minus a margin) for which the WTRU 210 receives packets from other WTRUs 210 in the same BSS.

As explained earlier, the deferred management has the need to perform across a coordinated manner across all WTRUs to enable the system to fully utilize the capacity gain that can be achieved by deferring management. Previously, what was presented was a signaling mechanism that allowed an AP to actively determine the values and set the delay management parameters of each WTRU associated with it in a direct manner, and this strategy ensures that The deferred management parameter settings for each WTRU may be consistent because they are calculated at a particular location (i.e., the AP) and, on the other hand, the facts on which this centralized planning is based However, the AP will collect a significant amount of measurements and signaling from the WTRUs, for example, the DTEDT that can determine which WTRU should use in order for the WTRU to not listen to a given co-channel additional BSS WTRU. For a numeric AP, the AP may need to determine the signal strength of the packet that the WTRU receives from the additional BSS WTRU.

An alternative to reducing the amount of signaling required in the system is that each WTRU is responsible for determining and setting the values of their deferred management parameters, but the AP will be set to determine the values and The guidelines, or rules, that WTRUs must follow when setting their deferred management parameters. Such a plan provides consistency between the deferred management policies used by each WTRU, while also allowing the system to mitigate some of the signaling between the WTRU and the AP.

3 is a diagram showing a signaling program executed in a wireless communication system 300, wherein the wireless communication system 300 includes an AP 305 and a plurality of WTRUs 310 _{1 -} 310 _N . The AP 305 will send a deferred management rule information 315 to at least one WTRU 310, and wherein it specifies a special rule that the WTRU 310 must follow in order to determine the value for its deferred management parameters. Alternatively, after the appropriate settings of the deferred management parameters have been calculated based on the rules sent by the AP 305, the WTRU 310 may include a delay due to execution of the rule. The (or) real value delay management rule execution management information 320 of the management parameters is returned to the AP 305, and, contiguously, when the deferred management rule information 315 is sent to other WTRUs 310, the information may be the AP 305. Used.

The information that must be transported to the WTRU 310 by the AP 305 is dependent on some range of the rules that the AP 305 would like to enforce. The following is a general, but novel, ruled example that can be used, and typically an instance of the input parameters that the AP 305 must provide in order for the WTRU 310 to perform the rule.

The first rule sets out which WTRU the WTRU(s) 310 is to listen to. This rule tells the (etc.) WTRU(s) 310 that it should set its DT/EDT to the highest possible value so that it can hear a particular set of WTRUs. In an embodiment, the AP 305 can select the set of WTRUs as all of the WTRUs in the BSS, and this means that the WTRUs 310 will set their DT/EDT parameters as high as possible. But at the same time still ensure that they can hear all the WTRUs in their BSS.

In the preferred embodiment, the rules that the WTRU 310 needs to follow, and the list of WTRUs that the WTRU 310 needs to listen to, may be included in a single message, but in another In the embodiment, it is also possible to carry in two separate pieces of information. In addition, when determining the value of the parameter, the information may also indicate a margin M that the WTRU 310 should use. In this case, if the WTRU 310 decides that it can hear all of its neighbors having a maximum value of -85 dBm DT/EDT, then a tolerance of 3 dBm means that the WTRU 310 will have to have its DT/EDT The parameter is set to -85dBm - tolerance = -88dBm.

This rule can be summarized by the following equation: DT/EDT _{W T R U} =min_function(max DT/EDT ₁ , max DT/EDT ₂ ,...max DT/EDT _N )-M Equation (1)

Where max DT/EDT _n is the maximum DT/EDT required to hear the WTRU _n , where n is a WTRU identifier and the M system represents the tolerance, and all of these values are by the AP 305 is provided.

In addition, another preferred rule is to indicate to the WTRU 310 the set of WTRUs on which it needs to be audible, and the rule is to inform the WTRU 310 that its transmission power should be set to the lowest possible value to Make sure it will be heard by a certain set of WTRUs.

In an embodiment, the AP 305 will determine all WTRUs that the WTRUs set to include in the BSS, and this means that the WTRUs 310 will set their transmission power to the lowest possible. Values to ensure that they are audible to all WTRUs located in their BSS.

In the preferred embodiment, the rules that the WTRU 310 needs to follow and the list of WTRUs that the WTRU 310 needs to listen to will be included in a single message, but in another embodiment Among them, it is also transported between two separate pieces of information. The information may also indicate the DT/EDT value used by each of the WTRUs that need to hear the WTRU 310. Additionally, the information may also include the WTRU 310 should use when determining the value of the transmission power parameter. A tolerance, for example, if the WTRU 310 determines that a power of 8 dBm is such that it can be heard by all of the WTRUs provided in the list of the AP 305, then a tolerance 3 dBm would mean that the WTRU 310 would set its transmit power to 8 dBm + tolerance = 11 dBm. In addition, the information could also indicate that the WTRU 310 should not be disconnected while reducing its transmit power. The minimum transmission rate.

This rule can be summarized by the following equation: Tx_Power _{W T R U} =max_function(min_function(min Tx_Power ₁ ,min Tx_Power _{2 , . . .} min Tx_Power _N )+M),min Tx_Power _{R A T E} ) (2)

Where min Tx_Power _i = DT/EDT + WTRU _{i of} wTRU _i and path loss between WTRUs, and min Tx_Power _{R A T E} is the minimum transmission power to achieve the required transmission rate, and min Tx_Power _n is heard by WTRU _n The minimum transmission power required, where n is a WTRU identifier.

Although the features and elements of the present invention are described in terms of a preferred combination of specific embodiments, each feature or element can be used separately without the need for additional features and elements of the preferred embodiment. Or in combination with or without the other features and elements of the invention.

AP. . . Access point

WTRU. . . Wireless transmission/reception unit

A more detailed explanation of the present invention can be obtained by the following description as exemplified and associated with the accompanying drawings, wherein: FIG. 1 shows a deferred management according to one of the present inventions Signalling flow diagram of the signaling program, and among the programs, an AP defines a delay parameter used by a plurality of WTRUs; and FIG. 2 shows a one used during WTRU measurement according to the present invention. a signal transmission flow chart for delaying the management signal transmitting program; and FIG. 3: showing a signal transmission flow chart for delaying the management signal transmission program according to one of the present invention, and wherein at least one WTRU uses the delay The management rules are defined by the AP.

AP. . . Access point

WTRU. . . Wireless transmission/reception unit

Claims (20)

A method for delay management of an access point (AP), the method comprising: transmitting a first message to request a deferred management capability report of a WTRU, wherein the first message includes a delay management rule supported by the AP; receiving a second message, where the second message includes a deferred management capability indicator and a deferred management rule supported by the WTRU; and transmitting a third message to respond to the second message, where The third message includes a plurality of additional deferred management rules including a transmission power parameter and an idle channel assessment energy detection (CCA-ED) parameter. The method of claim 1, further comprising: receiving a response message to respond to the transmission of the third message, indicating receipt of the additional delay management rules. The method of claim 1, wherein the third message comprises at least one of a maximum transmission power, a minimum transmission power, and a dynamic range. The method of claim 1, wherein the third message includes a minimum delay threshold (DT)/energy detection threshold (EDT) for the WTRU and a maximum DT for the WTRU. At least one of the EDTs. The method of claim 1, further comprising: comparing a plurality of delay management capabilities of the WTRU associated with the AP; And determining an ideal energy detection threshold (EDT) for the WTRUs associated with the AP. The method of claim 1, wherein the third message is transmitted as a single broadcast signal. A method for delay management of a wireless transmit/receive unit (WTRU), the method comprising: receiving a first message requesting a delay management capability report, wherein the first message comprises an access point (AP) supported Deferring the management rule; transmitting a second message, wherein the second message includes a deferred management capability indicator and a deferred management rule supported by the WTRU; and receiving a third message to respond to the second message, wherein the third message A plurality of additional deferred management rules are included, and the additional deferred management rules include a transmission power parameter and an idle channel assessment energy detection (CCA-ED) parameter. The method of claim 7, further comprising: transmitting a response message to respond to receipt of the third message, indicating receipt of the additional delay management rules. The method of claim 7, wherein the third message comprises at least one of a maximum transmission power, a minimum transmission power, and a dynamic range. The method of claim 7, wherein the third message includes a minimum delay threshold (DT)/energy detection threshold (EDT) for the WTRU and a maximum DT for the WTRU. EDT At least one of them. An access point (AP) for deferring management, the AP comprising: a transmitter configured to transmit a first message to request a deferred management capability report of a WTRU, wherein the a message includes a deferred management rule supported by the AP; a receiver configured to receive a second message, wherein the second message includes a deferred management capability indicator and a deferred management rule supported by the WTRU; and wherein the message The transmitter is further configured to transmit a third message to echo the second message, wherein the third message includes a plurality of additional delay management rules, the additional delay management rules including a transmit power parameter and an idle channel assessment energy Detection (CCA-ED) parameters. The AP of claim 11, wherein the receiver is further configured to receive a response message to echo the transmission of the third message, indicating receipt of the additional delay management rules. The AP of claim 11, wherein the third message comprises at least one of a maximum transmission power, a minimum transmission power, and a dynamic range. The AP of claim 11, wherein the third message includes a minimum delay threshold (DT)/energy detection threshold (EDT) for the WTRU and a maximum DT for the WTRU. At least one of the EDTs. The AP of claim 11, further comprising: a processor configured to compare the plurality of APs associated with the AP The WTRU's deferred management capabilities determine an ideal energy detection threshold (EDT) for the WTRUs. The AP of claim 11, wherein the transmitter is further configured to transmit the third message as a single broadcast signal. A WTRU for deferring management, the WTRU comprising: a receiver configured to receive a first message to request a deferred management capability report of the WTRU, wherein the first message includes a a deferred management rule supported by an access point (AP); a transmitter configured to transmit a second message, wherein the second message includes a deferred management capability indicator and a deferred management rule supported by the WTRU; and wherein the The receiver is further configured to receive a third message to echo the second message, wherein the third message includes a plurality of additional delay management rules, the additional delay management rules including a transmit power parameter and an idle channel assessment energy Detection (CCA-ED) parameters. The WTRU as claimed in claim 17, wherein the transmitter is further configured to transmit a response message to echo the transmission of the third message, indicating receipt of the additional delay management rules. The WTRU as claimed in claim 17, wherein the third message comprises at least one of a maximum transmission power, a minimum transmission power, and a dynamic range. The WTRU as claimed in claim 17, wherein the third message includes a minimum delay threshold (DT)/energy for the WTRU An amount detection threshold (EDT) and at least one of a maximum DT/EDT for one of the WTRUs.