CN101288250A

CN101288250A - Method and apparatus for receiving an allocated transmission period in a wireless communication system

Info

Publication number: CN101288250A
Application number: CN200680038377.XA
Authority: CN
Inventors: 张景训; 朴钟爱; 李东俊; 金泳秀; 黄孝善
Original assignee: Samsung Electronics Co Ltd
Current assignee: Zhongheng Technology Co.,Ltd.
Priority date: 2005-10-18
Filing date: 2006-10-17
Publication date: 2008-10-15
Anticipated expiration: 2026-10-17
Also published as: CN101288250B; CN101292447B; CN101288249B; CN101292447A; CN101288249A

Abstract

An apparatus and method is provided for efficiently allocating a transmission period in a WLAN system. An access point (AP) transmits a PSMP message providing a downlink period and an uplink period provided to each station (STA), and at least one sub PSMP frame indicating a period of at least one of a downlink and an uplink for an STA requiring additional resource allocation. After exchanging data with the AP in the downlink and uplink periods provided by the PSMP frame, if there is a need for additional resource allocation, the STA receives the at least one sub PSMP frame and exchanges data with the AP in the period provided by the each sub PSMP frame.

Description

The method and apparatus and the system thereof that distribute transmission period in the wireless communication system

Technical field

The present invention relates generally to a kind of wireless communication system, specifically, relate to the method and apparatus and the system thereof of the transmission period in a kind of transmission frame period of distributing Radio Network System effectively.

Background technology

Along with the expansion of recent development of wireless communication devices and the wireless device that causes, increasing demand via the transfer of data of the high speed of wireless link, high reliability.The wireless lan (wlan) that is developed to satisfy this demand comprises: stand (STA), and it is a mobile data communication device; And access point (AP), can with the STA swap data.The AP and the STA that are positioned at the same wireless service coverage are considered to Basic Service Set (BSS).

Particularly, improved wlan system uses multiple-input, multiple-output (MIMO) technology and OFDM (OFDM) technology of a plurality of transmitting antennas and a plurality of reception antennas to realize high-throughput by adopting.In this wlan system, the STA that is arranged in a wireless service coverage uses the AP assigned radio resource to send or the reception data.AP is with the form distributing radio resource of phase resource (phase resource), and term " phase resource " is meant that STA or AP can send the time period of data as used herein.

Fig. 1 illustrates the structure of the transmission frame period in the general wlan system.

With reference to Fig. 1, in the transmission frame period 100 with the definite regular length of system, AP sends MAP (mapping) frame 110 of indication to the phase resource allocation of whole transmission frame period 100.MAP frame 110 comprises: down link MAP 120, and indication AP can send the time period of data; With up link MAP 122, indication STA can send the time period of data.Down link MAP 120 comprises: the amount field 130 of STA and at least one STA information field 132 of determining based on the amount field 130 of STA.Similarly, up link MAP 122 comprises: the amount field 134 of STA and at least one STA information field 136 of determining according to the amount field 134 of STA.STA information field 132 and 136 each all comprise: STA id field 140 and 144, indication has distributed downlink transmission time section and the STA of up link time period; With time migration field 142 and 146, the time migration of STA is distributed in indication.

Distributed the time period of the corresponding STA information indication of STA in downlink transmission time section 112 of the time period in the MAP frame 110 to receive data, and the time period of the corresponding STA information indication in the up link time period 114 send data.The At All Other Times section of STA the time period of indicating except the time period and the MAP frame 110 of transmission MAP frame 110 keeps park mode.Can be based on competition, by the competition time period 116 after the STA visit up link time period 114.

By this way, AP estimates the stock number that each STA needs in a transmission frame period 100, and estimates to distribute up link time period and downlink transmission time section according to this.Yet, when AP has over-evaluated the stock number of STA needs, wasted Radio Resource, reduced data throughput performance.In this case, STA can not use assigned radio resource.In addition, owing to give specific STA with this resource allocation, so other STA can not re-use this resource.When AP had underestimated the stock number of STA needs, before next at least transmission frame period, STA can not be assigned with the resource that it needs, and has experienced the transmission delay and the shake of uplink service.The service quality (QoS) that transmission delay and effect of jitter STA need.In addition, if owing to the shortage of the resource of the distribution of STA makes STA enter the competition time period 116, then in the competition time period, STA can not operate in park mode, the waste energy.

Therefore, determine by scheduling that at AP needs are a kind of to prevent the minimizing of data throughout and the waste of STA energy, and distributes the technology of time period exactly in the wireless communication system of up link time period that STA needs and downlink transmission time section.

Summary of the invention

For from addressing the above problem at least in essence and/or shortcoming, and following advantage is provided at least, the invention provides the transmission period distribution method and equipment and the system thereof that minimize the waste of STA energy under a kind of situation that in wireless communication system, does not reduce data throughout.

The invention provides a kind of method and apparatus and system thereof that distributes the transmission period of STA needs more than two MAP frames neatly that in wireless communication system, use.

The invention provides a kind of method and apparatus and system thereof that the MAP frame is distributed to the mistake required time period of recovery of down link data and/or uplink data STA of adding that in Radio Network System, after use MAP frame is distributed to STA with transmission period, use.

According to an aspect of the present invention, provide a kind of method of in Radio Network System, distributing transmission period.Described method comprises: at least one that sends initial downlink link time period and initial uplink time period in transmission frame period offers multi-wheel energy saving (PSMP) frame of station (STA); Described STA receives data in the initial downlink link time period, and described STA sends data in the initial uplink time period; In initial downlink link time period and initial uplink after the time period, send the sub-PSMP frame of the additional downlink link time period that is provided for resending down link data in transmission frame period; And resend down link data in transmission frame period.

According to a further aspect in the invention, provide a kind of method that in Radio Network System, receives the transmission period that distributes.Described method comprises: receive at least one multi-wheel energy saving (PSMP) frame that initial downlink link time period and initial uplink time period are provided by access point (AP) in transmission frame period; In transmission frame period, described AP sends data in the initial downlink link time period, and described AP receives data in the initial uplink time period; In initial downlink link time period and initial uplink after the time period, receive the sub-PSMP frame of the additional downlink link time period that is provided for resending down link data in transmission frame period; And resend down link data in transmission frame period.

According to a further aspect in the invention, provide a kind of access point (AP) equipment that in Radio Network System, distributes transmission period.Described AP equipment comprises: processor, generation offers multi-wheel energy saving (PSMP) frame of station (STA) with initial downlink link time period of distributing and at least one of initial uplink time period, and produces the sub-PSMP frame of the additional downlink link time period that is provided for resending down link data; And transceiver, the PSMP frame is sent to STA, described STA receives data in the initial downlink link time period, described STA sends data in the initial uplink time period, in initial downlink link time period and initial uplink after the time period, send sub-PSMP frame in transmission frame period, and resend the data that receive in the initial downlink link time period in transmission frame period.

According to a further aspect in the invention, provide a kind of station (STA) equipment that in Radio Network System, receives the transmission period that distributes.Described STA equipment comprises: processor, analyze at least one multi-wheel energy saving (PSMP) frame that initial downlink link time period and initial uplink time period are provided by access point (AP), and in initial downlink link time period and initial uplink after the time period, analyze the sub-PSMP frame of the additional downlink link time period that is provided for resending down link data; And transceiver, receive the PSMP frame from AP, the PSMP frame that receives is delivered to processor, in transmission frame period, described AP sends data in the initial downlink link time period, and described AP receives data in the initial uplink time period; And resend the data that AP sent in the initial downlink link time period in transmission frame period.

According to a further aspect in the invention, a kind of Radio Network System is provided, described Radio Network System comprises: access point (AP), send multi-wheel energy saving (PSMP) frame and sub-PSMP frame in transmission frame period, described PSMP frame offers each station (STA) with initial downlink link time period and initial uplink time period, and described sub-PSMP frame is provided for resending the additional downlink link time period of down link data; And STA, in transmission frame period, send data at initial downlink link time period AP, receive data at initial uplink time period AP, and the resending of receiving downlink data.

Description of drawings

By the detailed description of carrying out below in conjunction with accompanying drawing, above and other objects of the present invention, characteristics and advantage will become more apparent, wherein:

Fig. 1 illustrates the structure of the transmission frame period in traditional wlan system;

Fig. 2 A illustrates the configuration according to wlan system of the present invention;

Fig. 2 B is the block diagram that the exemplary configurations of AP in the wlan system shown in Fig. 2 A and each STA is shown;

Fig. 3 illustrates the structure according to transmission frame period of the present invention;

Fig. 4 is the sequential chart that illustrates according to the description of the power reduction effect of phase resource allocation of the present invention;

Fig. 5 illustrates according to exemplary error recovery operation of the present invention;

Fig. 6 is the flow chart that illustrates according to the operation of AP of the present invention; And

Fig. 7 is the flow chart that illustrates according to the operation of STA of the present invention.

Embodiment

Now describe the preferred embodiments of the present invention with reference to the accompanying drawings in detail.In the following description, for the clear and concise known function that is herein incorporated and the detailed description of structure omitted.

Distribute relevant the present invention is characterized in that a plurality of MAP (mapping) are provided frame with the transmission period in the wireless communication system, distribute to the downlink transmission time section and the up link time period at each station (STA) with indication access point (AP) in transmission frame period.The time period of distributing begins after the MAP frame is sent out immediately, and in transmission frame period, the MAP frame except a MAP frame is called as " MAP afterwards (sub-MAP) ".Sub-MAP frame is used for the mistake of down link and uplink data and recovers.Here, described wrong recover to comprise the data that send on the down link resend with up link on the transmission of affirmation (ACK) of the data that receive, and can comprise other error recovery scheme.

Although will describe the present invention with reference to the wireless lan (wlan) system based on IEEE 802.11 standards, but it should be appreciated by those skilled in the art that, under the situation that does not break away from the spirit and scope of the present invention, the distribution of phase resource (basic sides of the present invention) also can be applicable to have other wireless communication system of similar technique demand and channel format.

Fig. 2 A is the diagrammatic sketch that illustrates according to the configuration of wlan system of the present invention.

With reference to Fig. 2 A, AP 202 and 210 each all be connected to cable network 200, a plurality of STA 204,206,208,212 visit its relevant AP 202 and 210 via IEEE 802.11 physics (PHY) layer with the wireless link of controlling (MAC) agreement based on media interviews with 214, and transmit and receive data by a plurality of wireless channels.The STA 204 to 208 and the AP 202 that are positioned at same wireless service coverage 220 form a Basic Service Set (BSS).Be positioned at wireless service coverage 222 STA 212 and 214 and AP 210 form another BSS.The STA that is positioned at each BSS can be via corresponding AP swap data each other.AP 202 and 210 major function comprise data communication transmission, visit that another network (for example, cable network 200), roaming are supported, among the BSS synchronously, energy management support and being used for supports the control of the media interviews of BSS time-constrain service.

Fig. 2 B is the block diagram that is illustrated in the exemplary configurations of AP and each STA in the wlan system shown in Fig. 2 A.AP and STA can comprise: display 232, processor 234, transceiver 236, input unit 238, memory 240, random-access memory (ram) 242, read-only memory (ROM) 244 and common bus 230.Provide the exemplary configurations that illustrates only for convenience.Although in particular element and the operation thereof of this description as AP and STA, exemplary description does not limit the present invention with reference to Fig. 2 B.

With reference to Fig. 2 B, the transceiver 236 that is connected to the antenna (not shown) receives data, and the conversion of signals that receives is become the corresponding digital data.Processor 234 is in operating system (OS) and is included in the controller of operation under the control of other program among the ROM244, and the information that produces of processor 234 and storage are in RAM 242.

The main operation that is included in the processor 234 among the AP comprises: the generation of data and analysis, be positioned at the same wireless service coverage and be connected to AP STA time period distribution, at least one MAP frame of time period that indication distributes generation and based on the operator scheme control of the transceiver 236 of the time period of distributing.Specifically, the MAP frame of the first of the processor 234 of AP by being positioned at transmission frame is with initial resource R _InitProvide or distribute to STA.Receive ACK from STA if desired and maybe the data that resend are sent to STA, then the sub-MAP frame of processor 234 by sending immediately after expiring in the sequence duration relevant with a MAP frame of transmission frame distributed to corresponding STA in addition with section remaining time in the transmission frame period.It will be apparent to those skilled in the art that: term " ... immediately afterwards " is meant passing of the scheduled time in fact.

After the downlink/uplink time period of MAP frame indication expires, if necessary, then can send indication in addition at the down link of identical traffic frame period distribution and/or a plurality of sub-MAP of up link time period.The down link of sub-MAP frame indication and/or up link time period are after sub-MAP frame.

The main operation that is included in the processor 234 among the STA comprises: the generation/analysis of data, the generation of transmission frame and the MAP frame that receives based on the starting point from transmission frame are to the operator scheme control of transceiver 236.Processor 234 control transceivers 236, thus transceiver 236 receives the MAP frame in the starting point of each transmission frame from AP, and analyze this MAP frame and whether be included in wherein with the STA ID (sign) that determines STA oneself.If the STA ID of STA oneself is included in the MAP frame, the indication of STA information that then processor 234 will be relevant with STA ID about the down link that distributes and the information stores of up link time period in memory 240, then wake the receiver and the transmitter of transceiver 236 up in downlink transmission time section and up link time period respectively, thereby receive and/or send data.The receiver of transceiver 236 and transmitter enter park mode in the section At All Other Times except the time period of distributing.

If the data that receive from AP, have mistake, if perhaps STA will receive the ACK for the data that send to AP, then whether processor 234 monitoring of STA receive from AP immediately after the whole cycle of MAP frame indication expires and are designated as the wrong sub-MAP frame that recovers other resource of distributing, and when receiving sub-MAP frame, analyze the sub-MAP frame that receives.The whole cycle comprises all time periods that the MAP frame provides.

According to the present invention, the data that the downlink transmission time section of indicating at the MAP frame by the ACK affirmation in the up link time period subsequently sends.Confirm the data that the downlink transmission time section in sub-MAP frame indication sends in the up link time period of distributing in addition by ACK according to subsequently sub-MAP frame.In this case, can resend down link and the uplink data that needs resend in the time period that basis sub-MAP frame subsequently distributes.

The wlan system of similar common wireless communication systems is owing to interference and noise between multipath fading, STA may mistake occur in the data that send.In order to address this problem, automatic repetitive requests (ARQ) and mixed ARQ (H-ARQ) scheme have been proposed, in described scheme, receiver sends to transmitter with the request that resends of the data of failure.In these schemes, receiver uses ACK to give transmitter whether to occur error notification in the data that will receive.When receiving ACK, transmitter determines that receiver has successfully received corresponding data (that is the data of affirmation).Yet when not receiving ACK, transmitter determines that receiver receives corresponding data (that is unacknowledged data) failure.Therefore, when not receiving the ACK of expectation, transmitter resends all unacknowledged datas.

ARQ and H-ARQ scheme not only can be used general AC K, also can use piece ACK, wherein, for the transmission data of each packing, can use described general AC K to give transmitter with the success/failure notification of Data Receiving.In piece ACK scheme, transmitter sends a plurality of bags continuously, then by piece ACK the bag whether receiver successfully receives transmission is notified to this transmitter together.

The data of STA transmission/reception can accumulate in one assembles in the Medium Access Control (MAC) Protocol Data Unit (A-MPDU), and can A-MPDU be sent with the MAC service data unit (MSDU) with different communication flow identifier (TSID) at identical down link or up link time period.Piece ACK uses bitmap to represent the reception result (success/failure) of a plurality of MSDU, and here, bitmap is represented MSDU success/failure of described a plurality of MSDU afterwards with " 1 (success) " or " 0 (failure) ".Piece ACK has form and the size according to the quantity optimization of the MSDU that confirms.

Simple block ACK can comprise sequence number and the bitmap of a MSDU who sends piece ACK.If necessary, then use the many TID piece affirmation (MTBA) that comprises with a plurality of bitmaps of communication identifier (TID) identification.In order to allow to transmit the piece ACK with large-size, AP distributes up link time period or downlink transmission time section.Here, piece ACK and general AC K will be called as ACK.

Fig. 3 illustrates the structure according to transmission frame period of the present invention.Although adjacent one another are in frame this illustrate and up link time period and downlink transmission time section, in real system for send and receive switch and handle may life period at interval.

With reference to Fig. 3, in the transmission frame period 300 with regular length, AP at first sends MAP frame 310a with the basic rate collection less than normal rate collection (comprising modulation scheme, encoding rate and data transfer rate).Make all STA in the service coverage can both receive MAP frame 310a like this.In the beginning of communication, send MAP frame 310a periodically according to the set time section of determining by the negotiation between AP and the STA (for example, being respectively 20ms and 10ms) for Internet protocol voice (VoIP) and Motion Picture Experts Group 4 (MPEG4).Send initialization transmission frame period 300 by MAP frame 310a.

For example, for the first downlink transmission time section 312a subsequently that indicates MAP frame 310a and the phase resource allocation of the first up link time period 314a, MAP frame 310a comprises: the first down link MAP 320a, and indication AP in the first downlink transmission time section 312a can send the time period of data; With the first up link MAP 322a, indication can send the time period of data at the first up link time period 314a STA.The first down link MAP 320a comprises: the amount field 330a of STA and at least one the STA information field 332a that determines based on the amount field 330a of STA.In an identical manner, the first up link MAP 322a comprises: the amount field 334a of STA and at least one the STA information field 336a that determines based on the amount field 334a of STA.

Each of

STA information field

332a and 336a all comprises:

STA id field

340a and 344a, and indication has been assigned with the STA of time period in the first downlink transmission time section 312a and the first up link time period 314a;

Time migration field

342a and 346a, the beginning of the time period of STA is distributed in indication; With

duration field

343a and 348a, the length of the time period that indication distributes.Each of

STA id field

340a and 344a all comprises at least one relevant identity (AID) part of each STA and gives at least one hardware address (MAC Address promptly) part of each STA.The STA ID that indication is used for the time period of broadcast/multi broadcast data is arranged to particular value, for example, and " 0 ".Each of

time migration field

342a and 346a is all with the interval of a plurality of scheduled time unit (for example, 4 μ s) indication from MAP frame 310a to the beginning of corresponding time period.Each of

duration field

343a and 348a all with a plurality of scheduled time unit (for example, 16 μ s) indication since the time period to the interval of finishing the length of section (that is, instruction time).

Downlink transmission time section and the up link time period of each STA at first distributed in the first down link MAP 320a of MAP frame 310a and first up link MAP 322a representative, and can the expected data amount that send be determined the first down link MAP 320a and the first up link MAP 322a according to data volume and the AP that the AP expectation sends.In this case, AP determines the first up link MAP 322a, thereby the first up link MAP 322a comprises and sending when being received in the data that the first up link time period 314a sends successfully and the required resource of notifying of failing.The time period that has been assigned with the corresponding STA information 332a indication of STA in the first downlink transmission time section 312a of phase resource at MAP frame 310a receives data, and the time period of the corresponding STA information 336a indication in the first up link time period 314a sends data.Down link and uplink data can comprise one or more A-MPDU and/or the MPDU that comprises payload and ACK.STA keeps park mode in the time period that sends MAP frame 310a with in the section At All Other Times except the time period of MAP frame 310a indication.

Each STA receives data in the time period of the distribution of the first downlink transmission time section 312a, and whether has mistake in the data of using the error correction code in the data that are included in reception to determine to receive.For example, each STA determines to be included among each MSDU among the A-MPDU whether have mistake.Form with ACK sends definite result and uplink data in the time period of the distribution of the first up link time period 314a.In order to be received in the data of the failure that the first downlink transmission time section 312a receives again, and be received in the ACK of the data of first downlink transmission time section 312a transmission, the reception of sub-MAP frame 310b after all time periods (that is, downlink transmission time section #1312a and up link time period #1314a) of STA monitoring MAP frame 310a indication expire.In the time period of the distribution of the second downlink transmission time section 312b of sub-MAP frame 310b indication and the second up link time period 314b, STA is transformed into enable mode.

To have wrong data and send the ACK of indication in order to resend in the successful reception of the data of first up link time period 314a reception what the first up link time period 314a sent, AP will be used for the additional resource (that is the second downlink transmission time section 312b) that mistake recovers and distribute to STA by sending sub-MAP frame 310b.In an identical manner, whether there is mistake in the data that AP uses the error correction code in the data that are included in reception to determine to receive.If have mistake in the data that the first downlink transmission time section 314a receives, then AP can distribute to STA with the second up link time period 314b by sub-MAP frame 310b, to allow resending of data.

That is to say that sub-MAP frame 310b comprises the second down link MAP 320b and the second up link MAP 322b, be used to indicate subsequently the second downlink transmission time section 312b and the phase resource allocation of the second up link time period 314b.Similarly, sub-MAP frame 310b can be sent together with the basic rate collection.The second down link MAP 320b comprises the amount field 330b of STA and at least one the STA information field 332b that determines based on the amount field 330b of STA.STA information field 332b comprises: STA id field 340b, and indication has distributed the STA of time period at the second downlink transmission time section 312b; Time migration field 342b, the beginning of the time period of STA is distributed in indication; With duration field 343b, the length of the time period that indication distributes.The element of STA information field 332b described above, the second up link MAP 322b is identical with the structure of the second down link MAP 320b, therefore will omit its detailed description.Distributed time period and AP swap data and the ACK of the STA of phase resource in the corresponding STA information 332b indication of the second downlink transmission time section 312b and the second up link time period 314b by sub-MAP frame 310b.

Although do not illustrate, if still need additional resource to distribute in addition, then a plurality of sub-MAP frames and can be included in addition in the transmission frame period 300 based on the up link time period or the downlink transmission time section of described sub-MAP frame.The transmission plan that use can have the MAP frame of one or more subframes is called as multi-wheel energy saving (PSMP) scheme, and MAP frame 310a and sub-MAP frame 310b are called as PSMP frame and sub-PSMP frame respectively.Each of PSMP frame and sub-PSMP frame all followed at least one downlink transmission time section or the up link time period by the indication of corresponding (son) PSMP frame, and the time period of (son) PSMP frame and corresponding indication is called as (son) PSMP sequence.In other words, come PSMP sequence of initialization by sending the PSMP frame, and STA only the time period of the indication of the PSMP frame in the PSMP sequence that begins with the PSMP frame wake up, thereby minimum power consumption.

Can be based on competition by the competition time period 316 of STA after the visit final nucleotide sequence duration.

Be noted that under the situation that does not break away from the spirit and scope of the present invention the element of MAP frame 310a shown in Fig. 3 and sub-MAP frame 310b and the arrangement of described element can change.For example, each of MAP frame 310a and sub-MAP frame 310b all comprises: STA id field, the time migration that is used for downlink transmission and a duration field and the time migration field and the duration field that are used for ul transmissions.In this case, if not free section is assigned to up link and down link, then corresponding duration field is set to sky (0).In addition, MAP frame 310a and sub-MAP frame 310b can comprise and be used to indicate whether and will following the field of sub-MAP frame or another sub-MAP frame.Whether STA analyzes the field in the sub-MAP frame, be the last sub-MAP frame in the current transmission frame period to determine this sub-MAP frame.

Fig. 4 is the sequential chart that illustrates according to the description of the power reduction effect of phase resource allocation of the present invention.

With reference to the diagrammatic sketch (a) of Fig. 4, transmission frame period 400 comprises: MAP frame 410a, the first downlink transmission time section 412a, the first up link time period 414a, sub-MAP frame 410b and the second downlink transmission time section 412b.MAP frame 410a provides the phase resource allocation of the first downlink transmission time section 412a and the first up link time period 414a.

With reference to the diagrammatic sketch (b) of Fig. 4, after the time period 420 receives MAP frame 410a, switch to park mode after, the time period 422 of the distribution of STA in the first downlink transmission time section 412a of MAP frame 410a indication wakes up, and from the AP receiving downlink data.Switch back park mode when the time period 422 expires after, STA keeps the time period 424 of the distribution of resting state in the first up link time period 414a of MAP frame 410a indication.In the time period 424, STA sends to AP with the sure ACK of down link data.Certainly ACK represents that STA has normally received all down link datas.Here, STA does not have uplink data to send, and STA does not need to monitor the sub-MAP frame 410b that is used for the mistake recovery.

With reference to the diagrammatic sketch (c) of Fig. 4, after the time period 430 receives MAP frame 410a, switch to park mode after, the time period 432 of the distribution of STA in the first downlink transmission time section 412a of MAP frame 410a indication wakes up, and from the AP receiving downlink data.Switch back park mode when the time period 432 expires after, STA keeps the time period 434 of the distribution of resting state in the first up link time period 414a of MAP frame 410a indication.In the time period 434, STA sends to AP together with the negative ACK (NACK) and the uplink data of down link.NACK is the ACK that the indication down link data damages.For example, NACK is such bitmap: only have the bit of the MSDU of the damage of being mapped to be set to " 0 (failure) ".Therefore, STA monitors the reception of sub-MAP frame 410b, so that be allocated for the resource that resends unacknowledged down link data and be used for the ACK of receiving uplink data.

That is to say that STA woke up in the time period 436, and monitor the reception of sub-MAP frame 410b.When receiving sub-MAP frame 410b, STA changes back resting state and waits for time period 438 in the second downlink transmission time section 414b of sub-MAP frame 410b indication.In the time period 438, STA receives data and the ACK that resends from AP.Although do not illustrate, can be before transmission frame period 400 expire, allocation map is to the time period of one or more additional MAP frames.

Fig. 5 illustrates according to exemplary error recovery operation of the present invention.Here, in the service coverage of AP 502, two STA (STA1 504 and STA2 506) communicate each other.

With reference to Fig. 5, AP 502 begins to send MAP frame 510a the transmission frame time period.MAP frame 510a is provided at the time period that the first downlink transmission time section 512 is distributed to the time period of STA1 504 and STA2 506 and distributed to STA1 504 and STA2 506 in the first up link time period 514.After sending MAP frame 510a, AP 502 at first sends to STA1 504 with down link data 512a, thereafter, down link data 512b is sent to STA2 506.Here, the down link data 512b that sends to STA2 506 is partly damaged during the transmission.

When AP 502 receives down link data 512a, STA1 504 sends to AP 502 in time period 522 of the first up link time period 514 of MAP frame 510a indication with the sure ACK 522b of uplink data 522a and down link data 512a.Here, owing to wherein also have remaining data queued 524 STA1 504 to send together in resource request (RR) message of time period 522 additional resource that data and request dispatcher queue data 524 are required.

After receiving the down link data 512b of failure from AP 502, STA2 506 sends to AP 502 in time period 532 of the first up link time period 514 of MAP frame 510 indication with the negative ACK 532b of uplink data 532a and down link data 512b.Because STA2 506 is without any remaining data queued, so STA2 506 does not send RR message in the time period 532.Uplink data 532a from STA2 506 is partly damaged during the transmission.

In response to from the uplink data 522a that comprises RR message of STA1 504 with from the uplink data 532a and the NACK 532b of the damage of STA2506, sub-MAP frame 510b indicates the ACK 516a that arrives STA1 504 in the second downlink transmission time section 516, and the downlink transmission time section that resends data 516b and NACK 516c that arrives STA2 506, be used for time period 526, and be used for time period 534 from uplink data 534a and the ACK 534b of STA2 506 from the uplink data 526a of STA1 504.Therefore, in the time period of sub-MAP frame 510b indication, AP 502 and STA 504 and STA 506 swap datas and control messages (ACK).That is to say that if AP 502 receives the NACK for the down link data 512b that sends to STA2 506, perhaps receive the ACK failure, then AP 502 is used in the resource that resends down link data 512b by sub-MAP frame 510b branch the poorlyest.

After STA 504 and STA 506 have received

uplink data

526a and 534a, the time period 518 that AP 502 divides the ACK518a and the 518b that are used in

transfer uplink data

526a and 534a by the second sub-MAP frame 510c.STA 504 and STA 506 are at the time periods 518 receiving uplink data 526a of the second sub-MAP frame 510c indication and ACK 518a and the 518b of 534a.MAP frame 310a, the first sub-MAP frame 510b and the second sub-MAP frame 510c and relative all down links and up link time period are all in a transmission frame period 500.

Fig. 6 is the flow chart that illustrates according to the operation of AP of the present invention.Here, for simply, AP only communicates with a STA.

With reference to Fig. 6, in step 602, AP indicates the MAP frame of the time period of distributing to current transmission frame period to come the current transmission frame period of initialization by sending.In step 604, AP sends to STA in the time period of MAP frame indication with down link data.If there is no send to the down link data of STA, then the MAP frame does not comprise and will distribute to the downlink transmission time section of STA.In this case, omitted step 604.

In step 606, AP determined whether to receive uplink data from STA in the time period of MAP frame indication.If there is no the MAP frame is distributed to the time period of STA, and then AP proceeds to step 610.Yet if receive uplink data from STA, AP proceeds to step 608, and wherein, AP divides the downlink transmission time section of the ACK that is used in transfer uplink data, then proceeds to step 610.

In step 610, whether the ACK of the down link data that AP determining step 604 sends is received in step 606.If the ACK that receives is sure ACK, then AP proceeds to step 614.Yet, if the ACK that receives is not sure ACK but negates NACK that AP distributes the downlink transmission time section that resends down link data in step 612, then proceeds to step 614.

In step 614, AP determines whether receive RR message from STA in step 606.If do not receive RR message, then AP proceeds to step 618, and whether determine needs additional resource to distribute in current transmission frame period.Yet if receive RR message in step 614, in step 616, AP distributes the resource of RR message request,, the up link time period, then proceeds to step 618 that is.

In step 618, AP determines whether to exist in other any resource of distributing of current transmission frame time period.If any one in step 608,612 and 616 distributed resource, then AP proceeds to step 620, wherein, AP produces the sub-MAP frame of the resource of at least one distribution of indication in step 608,612 and 616, after the time period of this MAP frame indication expires, send sub-MAP frame, then return step 604.Yet if do not have the resource of distribution in addition in the current transmission frame time period, AP proceeds to step 622, and wherein, AP waits for the starting point (that is, next transmission period of MAP) up to next transmission frame period, then returns step 602.

With reference to Fig. 7, in step 702, when when AP receives MAP, STA discerns the beginning of current transmission frame period, and detects downlink transmission time section and/or the up link time period of distributing to it.If the MAP frame indicating downlink link time period, then STA determines whether successfully receive down link data in the downlink transmission time section in step 704.If there is not the indicating downlink link time period, then STA proceeds to step 706.If successfully do not receive down link data, then STA proceeds to step 714, and wherein, STA prepares to receive sub-MAP frame, thereby is assigned with again the downlink transmission time section of receiving downlink data, then proceeds to step 706.Otherwise STA is directly to step 706.At this moment, send the ACK of down link data in the up link time period subsequently.

In step 706, STA determines whether to be received in the ACK of the uplink data that up link time period that the MAP frame distributes sends.If STA sends uplink data, then STA proceeds to step 716, and wherein, STA prepares to receive sub-MAP frame, thereby is allocated for the downlink transmission time section of the ACK of receiving uplink data, then proceeds to step 708.Otherwise STA is directly to step 708.

In step 708, STA determines whether sent RR message in the up link time period that the MAP frame distributes.If sent RR message, then STA proceeds to step 718, and wherein, STA prepares to receive sub-MAP frame, thereby is assigned with the resource of RR message request, then proceeds to step 710.Otherwise STA is directly to step 710.

In step 710, STA determines whether to be provided with the reception of sub-MAP frame, that is, again whether STA receiving downlink data, ACK that whether should the receiving uplink data or do not ask additional resource.If the reception of sub-MAP frame is not set, then in step 712, STA waits for the starting point (that is, next transmission period of MAP frame) up to next transmission frame period, and determining does not need additional resource in current transmission frame period, then returns step 702.Yet if be provided with the reception of sub-MAP frame, STA proceeds to step 720.

In step 720, the STA monitoring receives sub-MAP frame from AP after the whole cycle of MAP frame indication expires.When receiving sub-MAP frame, STA returns step 704, and carries out above-mentioned processing in the later time section of sub-MAP frame indication.

Be appreciated that from foregoing description, AP only distributes minimum resource by a MAP frame, over-evaluate with any of minimized resource, if and STA needs additional resource, then AP is distributed in the uplink resource of identical traffic frame period request immediately by sub-MAP frame, thereby has eliminated the reason (such as delay and jitter) that QoS reduces.In addition, STA maximizes the park mode retention time, and unnecessary long-time monitoring, thereby reduces the energy consumption of STA.

Although reference specific embodiment of the present invention shows and has described the present invention, it will be apparent to one skilled in the art that under the situation of the spirit and scope of the present invention that do not break away from the claim qualification, can carry out the various changes of form and details to it.

Claims

1, a kind of method of in Radio Network System, distributing the transmission period in the transmission frame period with default duration, described method comprises step:

Send multi-wheel energy saving (PSMP) frame in transmission frame period, described PSMP frame provides initial downlink link time period of distributing to station (STA) and at least one of initial uplink time period;

In the initial downlink link time period data are sent to described STA, receive data from described STA in the initial uplink time period;

In initial downlink link time period and initial uplink after the time period, send at least one the sub-PSMP frame of additional period section that is provided for resending in down link data and the uplink data in transmission frame period; And

Resend in down link data and the uplink data at least one in transmission frame period.

2, the method for claim 1, wherein sub-PSMP frame provides the additional downlink link time period of acknowledge (ACK), and described ACK indicates and successfully is received in the uplink data that the initial uplink time period sends.

3, method as claimed in claim 2 also comprises: the downlink transmission time section that provides at least one sub-PSMP frame sends ACK.

4, the method for claim 1, wherein can in a transmission frame period, send a plurality of sub-PSMP frames.

5, the method for claim 1 also comprises: the initial uplink time period that provides at the PSMP frame receives ACK from STA, and described ACK indicates and successfully is received in the data that initial downlink link time period that the PSMP frame provides sends.

6, the method for claim 1, wherein sub-PSMP frame provides the affix line link time period of distributing for the uplink data that resends the just up link time period failure before corresponding sub-PSMP frame transmission.

7, the method for claim 1, wherein sub-PSMP frame comprises:

The identifier of described STA (ID);

Begin skew, indicate the starting point of each time period that sub-PSMP frame provides; And

The duration field is indicated the length of each time period that sub-PSMP frame provides.

8, the method for claim 1, wherein the time period of the time period of PSMP frame indication and at least one sub-PSMP frame indication is included in the transmission frame period with regular length.

9, the method for claim 1, wherein ACK comprises that indication successfully receives the bitmap of at least one data unit.

10, a kind of method that in Radio Network System, is received in the transmission period that distributes in the transmission frame period with default duration, described method comprises step:

Receive at least one multi-wheel energy saving (PSMP) frame that initial downlink link time period and initial uplink time period are provided by access point (AP) in transmission frame period;

In transmission frame period, described AP sends data in the initial downlink link time period, and described AP receives data in the initial uplink time period;

In initial downlink link time period and initial uplink after the time period, receive the sub-PSMP frame of the additional downlink link time period that is provided for resending down link data in transmission frame period; And

Resend down link data in transmission frame period.

11, method as claimed in claim 10 wherein, can send a plurality of sub-PSMP frames in a transmission frame period.

12, method as claimed in claim 10 wherein, will confirm that in the initial uplink time period (ACK) sends to AP, and described ACK indicates the data of the downlink transmission time section reception that successfully is received in the indication of MAP frame.

13, method as claimed in claim 11, wherein, ACK comprises that indication successfully receives the bitmap of at least one data unit.

14, method as claimed in claim 10, wherein, sub-PSMP frame provides the affix line link time period of distributing for the uplink data that resends the just up link time period failure before corresponding sub-PSMP frame transmission.

15, method as claimed in claim 10, also comprise: if having mistake in the reception of the down link data that the downlink transmission time section just before the beginning of corresponding sub-PSMP frame receives, if perhaps just there is the uplink data that sends in the up link time period before the beginning of corresponding sub-PSMP frame, then monitor sub-PSMP frame.

16, method as claimed in claim 10, wherein, sub-PSMP frame comprises:

The identifier (ID) at described station (STA);

17, method as claimed in claim 10, wherein, all time periods that all time periods that the PSMP frame provides and sub-PSMP frame provide are included in the transmission frame period with regular length.

18, a kind of access point (AP) equipment that in Radio Network System, distributes the transmission period in the transmission frame period with default duration, described equipment comprises:

Processor, produce multi-wheel energy saving (PSMP) frame, described PSMP frame provides initial downlink link time period of distributing to station (STA) and at least one of initial uplink time period, and produces the sub-PSMP frame of the additional downlink link time period that is provided for resending down link data; And

Transceiver, the PSMP frame is sent to STA, described STA receives data in the initial downlink link time period, described STA sends data in the initial uplink time period, in initial downlink link time period and initial uplink after the time period, described transceiver sends sub-PSMP frame in transmission frame period, and resends the data that receive in the initial downlink link time period in transmission frame period.

19, AP equipment as claimed in claim 18, wherein, sub-PSMP frame is provided for the additional downlink link time period of acknowledge (ACK), and described ACK indicates and successfully is received in the uplink data that the initial uplink time period sends.

20, method as claimed in claim 19, wherein, the downlink transmission time section that provides at least one sub-PSMP frame sends ACK.

21, method as claimed in claim 18 wherein, can send a plurality of sub-PSMP frames in a transmission frame period.

22, AP equipment as claimed in claim 18, wherein, transceiver receives ACK in the up link time period that the PSMP frame provides from STA, and described ACK indicates and successfully is received in the data that initial downlink link time period that the PSMP frame provides sends.

23, AP equipment as claimed in claim 22, wherein, ACK comprises that indication successfully receives the bitmap of at least one data unit.

24, AP equipment as claimed in claim 18, wherein, sub-PSMP frame also provides in order to resend the just up link time period with wrong uplink data of the up link time period reception before corresponding sub-PSMP frame transmission.

25, AP equipment as claimed in claim 18, wherein, sub-PSMP frame comprises:

The identifier of described STA (ID);

26, AP equipment as claimed in claim 18, wherein, all time periods that all time periods that the PSMP frame provides and sub-PSMP frame provide are included in the transmission frame period with regular length.

27, a kind of station (STA) equipment that in Radio Network System, receives the transmission period of the distribution in the transmission frame period with default duration, described equipment comprises:

Processor, analyze at least one multi-wheel energy saving (PSMP) frame that initial downlink link time period and initial uplink time period are provided by access point (AP), and in initial downlink link time period and initial uplink after the time period, analyze the sub-PSMP frame of the additional downlink link time period that is provided for resending down link data; And

Transceiver, receive the PSMP frame from AP, the PSMP frame that receives is delivered to processor, in transmission frame period, described AP sends data in the initial downlink link time period, described AP receives data in the initial uplink time period, and described transceiver resends the data that AP sent in the initial downlink link time period in transmission frame period.

28, method as claimed in claim 27 wherein, can send a plurality of sub-PSMP frames in a transmission frame period.

29, STA equipment as claimed in claim 27, wherein, transceiver sends to AP in the up link time period of PSMP frame indication with ACK, and described ACK indicates the data of the downlink transmission time section reception that successfully is received in the indication of PSMP frame.

30, STA equipment as claimed in claim 29, wherein, ACK comprises that indication successfully receives the bitmap of at least one data unit.

31, STA equipment as claimed in claim 27, wherein, sub-PSMP frame provides in order to resend the just up link time period of the uplink data of the up link time period before corresponding sub-PSMP frame transmission.

32, STA equipment as claimed in claim 27, wherein, if have mistake in the reception of the down link data that the downlink transmission time section just before the beginning of corresponding sub-PSMP frame receives, if perhaps just there is the uplink data that sends in the up link time period before the beginning of corresponding sub-PSMP frame, then processor control transceiver makes it monitor sub-PSMP frame.

33, STA equipment as claimed in claim 27, wherein, sub-PSMP frame comprises:

The identifier (ID) at described station (STA);

34, STA equipment as claimed in claim 27, wherein, all time periods that all time periods that the PSMP frame provides and sub-PSMP frame provide are included in the transmission frame period with regular length.

35, a kind of Radio Network System with transmission frame period of default duration comprises:

Access point (AP), send multi-wheel energy saving (PSMP) frame and sub-PSMP frame in transmission frame period, described PSMP frame offers each station (STA) with initial downlink link time period and initial uplink time period, and described sub-PSMP frame is provided for resending the additional downlink link time period of down link data; And

STA in the transmission frame time period, sends data at initial downlink link time period AP, receives data at initial uplink time period AP, and the resending of receiving downlink data.

36, Radio Network System as claimed in claim 35, wherein, AP sends the affirmation (ACK) of the successful receiving uplink data of indication.

37, STA equipment as claimed in claim 36, wherein, ACK comprises that indication successfully receives the bitmap of at least one data unit.

38, Radio Network System as claimed in claim 35, wherein, STA is in the downlink transmission time section confirmation of receipt (ACK) of sub-PSMP frame indication.

39, Radio Network System as claimed in claim 35, wherein, in the up link time period that the PSMP frame provides, STA will confirm that (ACK) sends to AP, described ACK indicates and successfully is received in the data that downlink transmission time section that the PSMP frame provides receives.

40, Radio Network System as claimed in claim 35, wherein, each sub-PSMP frame provides in order to resend the just up link time period of the initial uplink data that receives of up link time period before corresponding sub-PSMP frame transmission.

41, Radio Network System as claimed in claim 35, wherein, if have mistake in the reception of the down link data that the downlink transmission time section just before the beginning of corresponding sub-PSMP frame receives, if perhaps just there is the uplink data that sends in the up link time period before the beginning of corresponding sub-PSMP frame, then STA monitors sub-PSMP frame.

42, Radio Network System as claimed in claim 35, wherein, sub-PSMP frame comprises:

The identifier of described STA (ID);

43, Radio Network System as claimed in claim 35, wherein, all time periods that all time periods that the PSMP frame provides and sub-PSMP frame provide are included in the transmission frame period with regular length.

44, Radio Network System as claimed in claim 35 wherein, sends a plurality of sub-PSMP frames in a transmission frame period.