CN101116277A

CN101116277A - Method for requesting and transmitting status report of a mobile communication system and therefor apparatus

Info

Publication number: CN101116277A
Application number: CNA2006800041325A
Authority: CN
Inventors: 金成勋; 李国熙; 郑景仁; 郭鲁濬
Original assignee: Samsung Electronics Co Ltd
Current assignee: Samsung Electronics Co Ltd
Priority date: 2005-02-07
Filing date: 2006-02-07
Publication date: 2008-01-30

Abstract

A method and apparatus are provided for reducing excessive retransmission delays which may occur due to the loss of the last packet of a transmission buffer in a Radio Link Control (RLC) layer of a mobile communication system. The method includes receiving a Service Data Unit (SDU) from a higher layer, dividing the SDU into a plurality of Packet Data Units (PDUs), and storing the PDUs in a buffer, setting a poll bit for a last PDU from among the PDUs stored in the buffer, the poll bit requesting a status report, and repeatedly transmitting the last PDU having the setup poll bit at least twice from a sender to a receiver, regardless of whether there is a request for retransmission of the last PDU.

Description

Be used to ask/transmit the method and apparatus of the status report of mobile communication system

Technical field

The present invention relates to mobile communication system.More specifically, the present invention relates to be used in the report of mobile communication system request/delivery status so that the method and apparatus of the delay that takes place when reducing packet retransmissions present.

Background technology

Current mobile communication system has been evolved and has been mainly the starter system that voice communications services provides for surmounting, and just develops towards the direction of the high speed high-quality wireless data packet communication system that data, services and multimedia service are provided now.Especially, as universal mobile communications service (UMTS) system that adopts in Europe based on the third generation (3G) mobile communication system global system for mobile communications (GSM) general packet radio service (GPRS), use Wideband Code Division Multiple Access (WCDMA) (WCDMA), it provides the consistency service, by this service, the user of mobile phone or computer can with 2Mbps at least transmit packet-based text, digitize voice or video and multi-medium data at a high speed, and no matter the user in the world where.

Fig. 1 is the block diagram of the typical UMTS mobile communication system of schematic illustrations.

With reference to Fig. 1, the UMTS system comprises core net (CN) 100 and a plurality of RNS (RNS) 110 and 120.

RNS

110 and 120 constitutes UMTS Terrestrial radio access network network (UTRAN).For UTRAN is linked to each other with Packet Data Network such as the internet, CN 100 comprises service GRPS support node (SGSN) and Gateway GPRS Support Node (GGSN).

RNS

110 and 120 comprises radio network controller (RNC) 111 and 112 and a plurality of Node B (Node B) 115,113,114 and 116.Particularly, RNS 110 comprises RNC 111 and NodeB 115 and 113, and RNS 120 comprises RNC 112 and Node B 114 and 116.According to their role,

RNC

111 and 112 can be categorized as Serving RNC, drift (drift) RNC and control RNC.The communication information of Serving RNC control subscriber equipment (UE) 130, and with CN 100 swap datas.Drift RNC directly is connected with UE 130 by radio communication, and control RNC controls the Radio Resource of each Node B.

By the interface that is labeled as " lub "

interconnect RNC

111 and 112 and Node B 115,113,114 and 116, and by the interface that is labeled as " lur " interconnect RNC 111 and 112.Although not shown in Fig. 1, by interface " Uu " interconnect UE 130 and UTRAN.Each

RNC

111 and 112 is to a plurality of Node B 115,113,114 and 116 distributing radio resource by RNC self control.Each Node B 115,113,114 and 116 offers UE 130 with institute's assigned radio resource.Arrange Radio Resource according to each sub-district, and the Radio Resource that is provided by each Node B is corresponding to the Radio Resource of specific cell.

UE 130 sets up wireless channel by using by the Radio Resource of Node B 115,113,114 and 116 specific cells of controlling, and the wireless channel that passes through to be set up transmits/receive data.UE130 only identifies physical channel based on the sub-district.Therefore, that distinguishes between Node B and sub-district has little significance, and in the following description, indistinction ground is used Node B and sub-district.

Fig. 2 illustrates the typical Uu interface between UE 130 and RNC 111 and 112 in detail.As shown in Figure 2, the Uu interface has the structure that comprises chain of command and user's face.Chain of command makes it possible to exchange control signal between UE and RNC, and user's face makes and can transmit user data between UE and RNC.

When the signal of processing controls face, this signal is through Radio Resource control (RRC) layer 204, Radio Link control (RLC) layer 210, medium access control (MAC) layer 212 and physics (PHY) layer 214.When the information 202 of process user face, this information via PDCP (PDCP) layer 206, broadcast/multi broadcast control (BMC) layer 208, rlc layer 210, MAC layer 212 and physical layer 214.

Physical layer 214 is to be used to utilize wireless tranmission techniques that the layer of information transfer service is provided, and corresponding to from the ground floor (L1) in 7 layers of OSI(Open Systems Interconnection).By transmission channel physical layer 214 is connected to MAC layer 212.By transmission channel, swap data between MAC layer 212 and physical layer 214.According to the scheme that in physical layer 214, is used for handling particular data, define the transformat (TF) of transmission channel.

MAC layer 212 receives data by logic channel from rlc layer 210, and by suitable transmission channel data passes is arrived physical layer 214.And MAC layer 212 receives data by transmission channel from physical layer 214, by suitable logic channel data passes is arrived rlc layer 210 then.In addition, MAC layer 212 inserts additional information in the data that receive by logic channel or transmission channel, perhaps analyze the additional information of inserting in the data that received, so that carry out suitable operation, or controls access operation at random.By logic channel interconnect MAC layer 212 and rlc layer 210.MAC layer 212 comprises a plurality of sublayers.

Rlc layer 210 is responsible for setting up and discharging logic channel.Each entity of rlc layer 210 can be with a kind of operation the in affirmation mode (AM), unacknowledged mode (UM) and the transparent mode (TM).The difference of the function that provides by them is distinguished this three kinds of operator schemes.The RLC AM entity of transmitter was carried out from the cutting apart, splice or fill of the data of higher layer, that is, RLC Service Data Unit (RLC SDU) generates segmentation (segment) thus, and each segmentation all has the size that is adapted to pass through the wireless channel transmission.Then, the RLCAM entity inserts the information of relevant cutting apart/splice/fill in the segmentation, generates protocol Data Unit (PDU) by inserting sequence number to segmentation, then RLC PDU is sent to lower layer, and promptly the MAC layer 212.The RLC AM entity of receiver is checked the sequence number of the RLC PDU that transmits from transmitter, so that determine whether any RLC PDU of existing entity to fail to receive, and the such RLC PDU of request retransmission.As noted, RLC AM key property is that it supports to retransmit RLC PDU.Especially, the RLC PDU that is used by RLC AM is called as " AMD PDU (AM data PDU) ".

PDCP layer 206 is positioned on the rlc layer 210.The head of the data that PDCP layer 206 compression transmits with the form of Internet Protocol (IP) grouping, and under the situation that the RNC that service is provided changes owing to the mobility of UE, nondestructively Data transmission.BMC layer 208 also is positioned on the rlc layer 210.BMC layer 208 supports to be used for identical data are sent to the broadcast service of a plurality of not particular UE that are positioned at specific cell.Radio Resource between rrc layer 204 distribution and release UTRAN and the UE.

As mentioned above, when RCL operates with affirmation mode (AM), the also unreceived grouping of receiver request retransmission, and transmit this repeat requests by the message that transmits " status report " by name.Yet when receiver failed to receive last grouping, receiver end can not be recognized needed this fact of request retransmission, thereby for repeat requests too much delay has taken place.

Therefore, there are needs to the system and method that in mobile communication system, effectively and efficiently reduces the delay that takes place when the packet retransmissions present.

Summary of the invention

Therefore, made embodiments of the invention solve the above-mentioned and other problems that occurs in the prior art, and a purpose of embodiments of the invention provides a kind of method and apparatus, is used for reducing the too much retransmission delay that the last grouping owing to the transmission buffer of Radio Link control (RLC) layer of having lost mobile communication system takes place.

Another purpose of embodiments of the invention provides a kind of method and apparatus, and the last grouping that is used for transmitting buffer repeats to transmit several times, and no matter the repeat requests of the receiver in the Radio Link of mobile communication system control (RLC) layer.

Another purpose of embodiments of the invention provides a kind of method and apparatus, be used for Radio Link control (RLC) layer in mobile communication system, before expiring, during not from the more high-rise grouping that receives the number that is enough to the reconstruct grouping, transmit the status report of receiver at predetermined timer.

In order to realize these and other purposes, provide a kind of in mobile communication system request be used to retransmit the method for the status report of control, the method comprising the steps of: (1) is from more high-rise reception Service Data Unit (SDU), SDU is divided into a plurality of Packet Data Units (PDU), and in buffer the storage this PDU, (2) for last PDU among the described PDU that is stored in this buffer poll bit is set, described poll bit solicited status report, and (3) repeat to transmit described last PDU that has the poll bit that has been provided with for twice at least from sender to receiver, and no matter whether exist retransmitting the request of described last PDU.

According to an embodiment of the invention on the other hand, provide request in a kind of Radio Link control (RLC) layer in mobile communication system to be used to retransmit the equipment of the status report of control, this equipment comprises: Packet Data Unit (PDU) building block, be used for from more high-rise reception Service Data Unit (SDU), and SDU is divided into a plurality of PDU; Transmit buffer, be used for storing PDU at buffer; Poll bit is provided with piece, is used to last PDU among the described PDU that is stored in this buffer that poll bit is set, described poll bit solicited status report; And cryptographic block, be used for described last PDU with the poll bit that has been provided with is encrypted, and described last PDU is sent to receiver, wherein repeat to transmit described last PDU at least twice from sender to receiver, and no matter whether exist retransmitting the request of described last PDU.

According to an embodiment of the invention on the other hand, a kind of method that transmits the status report be used to retransmit control in mobile communication system is provided, the method comprising the steps of: (1) receives PDU by low layer more from transmitter, the PDU that is received has set poll bit, this poll bit solicited status report; (2) determine whether the PDU that is received is the PDU that retransmits; (3) when the PDU that is received is the PDU that retransmits, ignore the poll bit of the PDU that is received, and not delivery status report; And (4) when the PDU that is received is not the PDU that retransmits, the delivery status report in response to poll bit.

According to an embodiment of the invention on the other hand, a kind of equipment that transmits the status report be used to retransmit control in mobile communication system is provided, this equipment comprises: decryption block, be used for receiving PDU from transmitter by low layer more, and PDU deciphering to being received, the PDU that is received has set poll bit, this poll bit solicited status report; Reception buffer is used to store the PDU through deciphering, up to described PDU through deciphering is reconstructed into corresponding SDU; Controll block when it is worked as the PDU that is received and is the PDU that retransmits, is ignored the poll bit of the PDU that is received, and delivery status report, and when working as the PDU that is received and not being the PDU that retransmits, the delivery status report in response to poll bit; And transmission block, be used for status report is sent to described transmitter.

According to an embodiment of the invention on the other hand, provide a kind of method that transmits the status report be used to retransmit control in mobile communication system, the method comprising the steps of: receive protocol Data Unit (PDU) by low layer more from transmitter; Whether the sequence number of definite PDU that is received is greater than the maximum sequence number in the sequence number of the PDU that has received; When the sequence number of the PDU that is received during greater than described maximum sequence number, stop to be used to produce the timer that status report triggers, and determine whether and to come the complete Service Data Unit of reconstruct (SDU) by using at least a portion among the PDU that in reception buffer, stores; When can not reconstruct complete SDU, restart described timer; And when described timer expires, status report is sent to transmitter.

According to an embodiment of the invention on the other hand, a kind of equipment that transmits the status report be used to retransmit control in mobile communication system is provided, this equipment comprises: decryption block is used to receive and decipher by low layer more and the protocol Data Unit (PDU) that transmits from transmitter; Reception buffer is used to store the PDU through deciphering, up to described PDU through deciphering is reconstructed into corresponding SDU; And controll block, its sequence number that is configured to work as the PDU that is received is during greater than described maximum sequence number, stop to be used to produce the timer that status report triggers, determine whether then and can come the complete Service Data Unit of reconstruct (SDU) by using at least a portion among the PDU that in reception buffer, stores, when can not reconstruct complete SDU, restart described timer, and when described timer expires, status report is sent to transmitter.

Description of drawings

From the detailed description below in conjunction with accompanying drawing, above-mentioned and other purposes of embodiments of the invention, feature and advantage will become clearer, in the accompanying drawing:

Fig. 1 is the block diagram of the typical UMTS mobile communication system of schematic illustrations;

The UE that Fig. 2 illustrates in detail at Fig. 1 and the structure of the typical Uu interface between the RNC;

Fig. 3 illustrates by the structure of the example RLC PDU of RLC AM entity handles according to an embodiment of the invention;

Fig. 4 is used for the diagram block diagram of the structure of example RLC AM entity according to an embodiment of the invention;

Fig. 5 is used for the diagram flow chart of the exemplary operations of RLC AM entity according to an embodiment of the invention;

Fig. 6 is the block diagram that is used for diagram example problem of generation when the last PDU that transmits buffer loses;

Fig. 7 is used for the block diagram of exemplary method that be used to handle RLC PDU of diagram according to the first embodiment of the present invention;

Fig. 8 is used for the flow chart of diagram according to the example transfer operation of the first embodiment of the present invention;

Fig. 9 is used for the flow chart of diagram according to the exemplary operations of the receiver of the first embodiment of the present invention;

Figure 10 is the block diagram that is used for the exemplary method of diagram processing RLC PDU according to a second embodiment of the present invention;

Figure 11 is the flow chart that is used for the example timer control operation of diagram receiver RLC AM entity according to a second embodiment of the present invention; And

Figure 12 is the flow chart that is used for diagram exemplary operations according to a second embodiment of the present invention.

Run through accompanying drawing, identical Reference numeral will be understood that to indicate identical part, assembly and structure.

Embodiment

Hereinafter, example embodiment of the present invention is described with reference to the accompanying drawings.In the following description, when the known function in this merging may make that with configuration theme of the present invention is not known, omit its detailed description.In addition, the various specific definitions that find in the following description are provided to help the overall understanding of embodiments of the invention, and it will be apparent to those skilled in the art that do not have such definition also can implement the present invention.

Whether wrong embodiments of the invention by determining in the sequence number of the grouping that is received whether to have lost grouping in or the grouping, reduce retransmission delay in the rlc layer of the mobile communication system of supporting retransmission packet.As the basis of the description of example embodiment of the present invention, will describe the operation of RLC AM entity in detail.

Fig. 3 illustrates by the structure of the example RLC PDU of RLC AM entity handles according to an embodiment of the invention.

With reference to Fig. 3, RLC PDU 300 comprises RLC PDU 305, length indicator part 310 and pay(useful) load 315.RLC PDU 305 comprises following field.

Data/control (D/C) bit field 320 is 1 bit flags, and whether its indication RLC PDU comprises data (that is RLC SDU) or status report only.As used in this, the RLC PDU that comprises data (that is RLC SDU) is called as " AMD PDU ".In sequence number (SN) field 325, insert 12 sequence number.Sequence number is the integer between 0 and 4095, and it increases for each AMD PDU is dull.Poll bit 330 is the fields that are used for asking the report of receiver delivery status.When poll bit 330 is set to " 1 ", its hint request receiver delivery status report.HE 335 is that the field after the expression HE 335 is length indicator part 310 or 2 bit fields of pay(useful) load 315.

Only when pay(useful) load 315 comprises RLC SDU, that is, when RLC PDU 300 is AMD PDU, just comprise length indicator part 310 among the RLC PDU 300.Length indicator part 310 comprises at least one length indicator 340 and at least one extended field 345.When RLC PDU 300 comprised the ending of RLCSDU, each length indicator 340 was positions of the ending of indication RLC SDU.Therefore, when having spliced a plurality of RLC SDU in RLC PDU 300, RLC PDU 300 comprises a plurality of length indicators.

Pay(useful) load 315 comprises one or more RLC SDU.Any RLC SDU can be divided, be inserted into then a plurality of AMD PDU, and perhaps, a plurality of RLC SDU can be spliced, be inserted into then an AMDPDU.

RLC AM entity is from least one RLC SDU of more high-rise reception, and division/splicing/filling RLC SDU generates RLC PDU by inserting AMD PDU 305 and one or more length indicator, then RLC PDU is sent to more low layer.After this, by more low layer and wireless channel, RLC PDU is sent to the other side RLC AM entity.

Fig. 4 is the diagram block diagram of the example structure of RLC AM entity according to an embodiment of the invention.RLC AM entity is carried out two-way communication, thus RLC AM entity 400 comprise translator unit 405 and receiving unit 410 the two.

With reference to Fig. 4, translator unit 405 generates AMD PDU 420a by using the RLC SDU 415 as more high-rise data, then the AMD PDU 420a that is generated is sent to the receiving unit of the other side RLC AM entity.In addition, where necessary, translator unit 405 is sent to status report 420b the receiving unit of the other side RLC AM entity.Receiving unit 410 receives AMD PDU 425a and status report 425b from the translator unit of the other side RLC AM entity, carries out retransmitting where necessary, comes reconstruct RLC SDU 430 by using AMD PDU 425a, and is sent to RLC SDU 430 more high-rise.

Particularly, the translator unit 405 of RLC AM entity 400 comprise cut apart/splicing block 435, RLC head add piece 440, re-transmission buffer 445, transmit buffer 450, poll bit is provided with piece 455 and cryptographic block 460.

When the receiving unit 405 of RLC AM entity 400 has received RLC SDU 415, cut apart/splicing block 435 cuts apart or splices RLC SDU 415, have the data of predetermined suitable size with generation.In addition, the RLC head adds piece 440 and inserts AMD PDU head to these suitably big or small data, generates AMD PDU thus.The AMD PDU that is added piece 440 generations by the RLC head is sent to re-transmission buffer 445 and transmits buffer 450.Before transmitting AMD PDU, it is stored in the transmission buffer 450.

MAC layer (not shown) determines whether to be transmitted in the AMD PDU that transmits storage in the buffer 450.On each transmission cycle, the number of the definite AMD PDU that will transmit of MAC layer.Then, according to the order of MAC layer, the AMD PDU of storage in the transmission buffer 450 is outputed to poll bit piece 455 is set.Poll bit is provided with the P position that piece 455 is provided with the AMD PDU that is exported.If poll is necessary, then the P position is set to " 1 ".Otherwise the P position is set to " 0 ".When piece 455 being set from poll bit receiving AMD PDU, the AMD PDU except AMD PDU head is encrypted and transmitted to cryptographic block 460, prevents that thus the third party from changing AMD PDU 420a.

Where necessary, by the control unit (not shown) structural regime of RLC AM entity 400 report 420b, and by translator unit 405 delivery status report 420b cryptographically not.Status report comprise expression till the time point of delivery status report, the information of the accepting state of the AMD PDU that also do not receive.Based on status report, the other side determines that it is with the AMD PDU that retransmits.Control unit determines whether to have taken place the status report triggering according to one of following example embodiment of the present invention.When the status report triggering had taken place, control unit generated status report.As described herein, control unit belongs to receiving unit 410, because control unit determines whether to have taken place the status report triggering by monitoring the AMD PDU that is received by receiving unit 410.

The receiving unit 410 of RLC AM entity 400 comprises that decryption block 465, reception piece 470, RLC head remove piece 475, SDU re-assemblies piece 480 and aforesaid control unit (not shown).Decrypted 465 deciphering of AMD PDU 425a by receiving unit 410 receives is passed to reception piece 470 then.Before the complete SDU of reconstruct, receive piece 470 and store AMD PDU according to the order of their sequence numbers always from decryption block 465.When the AMD PDU of the identical sequence number of the sequence number that has retransmitted the AMD PDU that has and stored, receive the AMD PDU that piece 470 is ignored re-transmission, the AMD PDU that perhaps will store replaces with the AMD PDU of re-transmission.When can reconstruct SDU, the AMD PDU relevant with this SDU is sent to the RLC head removes piece 475, the RLC head removes piece 475 and removes head from AMD PDU then.Then, SDU re-assemblies piece 480 the AMD PDU relevant with SDU is reconstructed into SDU, and the SDU with reconstruct is sent to more high-rise then.

When the other side RLC AM entity receives status report 425b, receiving unit 410 helps re-transmission buffer 445 to determine the AMD PDU that will retransmit the re-transmission buffer 445 that status report 425b is delivered to translator unit 405 thus.

In the example embodiment of this specification, transmitter is meant the RLC AM entity that mainly transmits RLC SDU at corresponding time point, and receiver transmits the RLC AM entity of mainly reporting in corresponding time point delivery status.For example, in the downlink service such as file transfer protocol (FTP) (FTP), the user serves as receiver, because the user receives data, and the delivery status report in response to Data Receiving, and network serves as transmitter, because it transmits data, receiving state report, execution re-transmission then.Promptly, serve as the RLC AM entity of transmitter and assign to transmit RLC SDU by its transport unit, and by its acceptance division receiving state report of assigning to, and the RLC AM entity that serves as receiver assigns to receive RLC SDU by its acceptance division, and by the delivery status report of assigning to of its transport unit.

As mentioned above, the automatic repeat requests of RLC AM entity support (ARQ) operation.The sequence number of the AMD PDU that the receiver inspection is received, and transmit the status report that is used for reporting the failure that receives any PDU.Based on this status report, transmitter is carried out the re-transmission of the PDU that does not receive.Can come the delivery status report according to the order of transmitter or based on the determining of receiver self.

Fig. 5 is the diagram flow chart of the exemplary operations of RLC AM entity according to an embodiment of the invention.

In step 515, transmitter 505 sends AMD PDU to receiver 510.When satisfying pre-provisioning request in step 517, transmitter 505 is provided with and transmits the poll bit of AMD PDU in step 520.As used in this, poll triggers the condition that satisfies the requirement of setting up poll bit that is meant, and can be as give a definition (but being not limited thereto):

-when remaining PDU is last PDU in transmitting buffer, can set up the poll bit of AMD PDU;

-when remaining PDU in re-transmission buffer is last PDU, can set up the poll bit of AMD PDU;

-when no matter when transmitting the AMD PDU of predetermined number, can set up the poll bit of AMD PDU; And

-on each predetermined period, can set up poll bit.

Transmitter can comprise that the poll that surpasses triggers.Then, when one of them poll triggered generation, transmitter was provided with poll bit.

When receiving the AMD PDU with poll bit of setting up, receiver 510 generates in step 525 and reports to transmitter 505 delivery statuss.In this step, comprise that the RLC PDU of status report is called as " status PDU ".For example, the sequence number of the sequence number of the status report PDU that comprises till current point in time being received and the PDU that also do not receive the two.

When receiving AMD PDU, receiver 510 is all confirmed the sequence number of the AMD PDU that received, and the parameter of management VR (R) by name and VR (H).The value that V parameter R (R) storage obtains by the sequence number that " 1 " is added the AMD PDU that most recent receives from the AMD PDU that arranges according to the order of sequence.The sequence arrangement of AMD PDU is hinting also not failure in the reception of PDU.When with PDU[x] when being defined as AMD PDU with sequence number x, for example, if receiver 510 is just receiving and is cushioning PDU[1], PDU[2], PDU[3] and PDU[5], PDU[1], PDU[2] and PDU[3] be in the state and the V parameter R (R) that are arranged according to the order of sequence and have value 4.That is to say the sequence number of the AMD PDU that VR (R) representative expectation will receive.When receiver 510 received the AMD PDU with sequence number identical with VR (R), receiver 510 upgraded VR (R) according to the AMDPDU that is received.In above-mentioned example, when receiving PDU[4] time, VR (R) is updated to 6.

The value that V parameter R (H) storage obtains by the highest sequence number that " 1 " is added from the sequence number of the AMD PDU that receives and cushion till current point in time.V parameter R (H) is used to discern the PDU that does not receive.When the sequence number of the AMD PDU that receives AMD PDU and received during more than or equal to the currency of VR (H), undated parameter VR (H).

Status report comprises the value of VR (R), the AMD PDU that it is received till current point in time to sender report.Status report comprises the sequence number of the AMD PDU that does not also receive till current point in time in addition.

When receiving status report, transmitter 505 abandons from re-transmission buffer and is identified as the AMD PDU that has been received by receiver 510, and re-transmission is identified as the AMD PDU that is not also received by receiver 510.

In step 530, transmitter 505 transmits new or retransmits AMD PDU to receiver 510.When satisfying predetermined condition, receiver 510 generates in step 540 and reports to receiver 510 delivery statuss.As used in this, this is called when having satisfied the requiring of delivery status report, and has triggered status report.Can following definition status trigger (but being not limited thereto):

-when detecting the PDU that does not receive, but the delivery status report.That is,, determine to exist the PDU that does not receive when the sequence number of the AMD PDU that is received during greater than VR (H).For example, when VR (H) be 10 and receive PDU[11] time, determine not receive PDU[10];

-when receiving AMD PDU with poll bit of setting up, but the delivery status report; And

-on each predetermined period, but the delivery status report.

As mentioned above, the report of transmitter order receiver delivery status, perhaps spontaneously delivery status report of receiver makes transmitter identify the PDU that receiver fails to receive, and retransmits this PDU then.Yet under special case, receiver is status report or come delivery status report with sizable time delay again perhaps.Hereinafter such situation is described with reference to Fig. 6.

Fig. 6 is the block diagram that is used for the example problem that diagram takes place when losing the last PDU that transmits buffer.

With reference to Fig. 6, remaining last AMD PDU is provided with poll bit in 605 pairs of transmission buffers of transmitter.Transmitter 605 is from more high-rise reception RLC SDU 610, and RLC SDU 610 is divided into three RLCPDU 615,620 and 625.RLC PDU 615 has sequence number x, and RLC PDU 620 has sequence number (x+1), and RLC PDU 625 has sequence number (x+2).Transmitting RLC PDU[x] 615 and RLC PDU[x+1] after 620, transmitter 605 is RLC PDU[x+2] poll bit is set, and transmit RLC PDU[x+2].

For example, suppose that receiver 630 has received RLC PDU[x] 615 and RLC PDU[x+1] 620, but also do not receive RLC PDU[x+2] 625.Yet, at RLC PDU[x+2] the RLC PDU that will not receive again after 625, and receiver 630 can not identify receive RLC PDU[x+2] 625 failure.

More specifically, receiving RLC PDU[x+1] 620 o'clock, receiver 630 is updated to (x+2) with VR (H).After this, only when receiver 630 received have sequence number next RLC PDU (not shown) of (x+3), receiver 630 just can identify and also not receive the RLC PDU[x+2 of sequence number for (x+2)] 625.Yet, because have the RLC PDU[x+2 of sequence number (x+2)] and the 625th, last PDU that transmit is so receiver 630 can not identify the PUD that existence does not also receive.Therefore, do not trigger status report, and no matter this fact of PDU that does not receive in addition.In addition, because during it transmits, lost RLC PDU[x+2 with poll bit of setting up] 625, so can not trigger status report by poll bit.

Usually, will comprise that by RLC AM entity the RRC message of the control information of rrc layer is divided into a plurality of RLC PDU.Thereby, because RRC message may comprise with call handling process during RRC connect relevant various control informations, so must send RRC message to the other side apace.In addition, only after confirming to have received a RRC message fully, rrc layer just transmits next RRC message.Thereby the delay of the re-transmission of RRC message may become the reason of the delay of remarkable increase call treatment.

In said circumstances, transmitter 605 can not be discerned RLC PDU[x+2] failure of 625 reception, and do not carry out re-transmission.Even when receiver 630 has been set to periodically the delivery status report, before the following one-period that the periodicity of status report transmits, can not identify RLC PDU[x+2 yet] failure of 625 reception, therefore, as much ground has postponed re-transmission.When receiver 630 did not set up the periodicity of status report to transmit, receiver 630 can not require to retransmit RLC PDU[x+2 before it receives RLC PDU by next RLC SDU] 625.

First example embodiment

According to first example embodiment of the present invention, in order to solve above-mentioned and other problems, when the poll bit of setting up the AMD PDU that will transmit and AMD PDU are last PDU that stores in buffer, promptly, when the AMD PDU that will not transmit after last AMD PDU, the last AMD PDU that will have the poll bit of setting up repeats to transmit several times.At this moment, the last AMD PDU that will have the poll bit of setting up repeats to transmit pre-determined number, and no matter whether there is repeat requests from receiver.

Fig. 7 is used for the block diagram of exemplary method that be used to handle RLC PDU of diagram according to the first embodiment of the present invention.

With reference to Fig. 7, transmitter 705 receives RLC SDU 710, RLC SDU 710 is divided into three RLC PDU 715,720 and 725, and the RLC PDU 715,720 and 725 of three divisions is stored in the buffer.For example, RLC PDU 715 has sequence number x, and RLC PDU 720 has sequence number (x+1), and RLC PDU 725 has sequence number (x+2).Transmitting RLC PDU[x] 715 and RLC PDU[x+1] after 720, transmitter 705 is RLC PDU[x+2] 725 poll bit is set, and transmit RLC PDU[x+2] 725.At this moment, because RLC is PDU[x+2] the 725th, last PDU that stores in buffer is so shown in

Reference numeral

730 and 735, with RLC PDU[x+2] 725 re-transmissions are several times.

During in receiving RLC PDU 725,730 and 735 at least one with poll bit of setting up, the report of receiver 740 delivery statuss.Preferably, also a delivery status report is once when above even receiver 740 receives among the RLC PDU 725,730 and 735 with poll bit of setting up one at it.

Fig. 8 is the flow chart according to the example transfer operation of the first embodiment of the present invention.Arrive more at the initial AMD PDU that transmits and promptly to begin this transfer operation before the low layer.

With reference to Fig. 8, in step 805, the AMD PDU that will transmit submits to more low layer, and in step 810, transmitter determines whether the AMD PDU that will transmit is last PDU that dispatches among the PDU.Scheduling PDU is meant the PDU that is in following state: can transmit this PDU at any time, i.e. and this PDU of storage in transmitting buffer, and can not forbid the transmission of this PDU owing to window operation etc.Because RLC AM entity is carried out current control by window, so transmitter can not be at the outside PDU that transmits of window.For example, if in the transmission buffer of RLC AM entity, store PDU[10] to PDU[100], and at PDU[10] to PDU[73] go up the formation window, last PDU that then dispatches among the PDU is PDU[73].

If the AMD PDU that transmits is not last PDU among the scheduling PDU, then transmitter advances to step 830, and in step 830, transmitter transmits this AMD PDU.Yet if the AMD PDU that transmits is last PDU among the scheduling PDU, transmitter advances to step 815.

Then, in step 815, transmitter is provided with poll bit for this AMD PDU, then in step 820, transmits this AMD PDU.In step 825, transmitter retransmits this AMD PDU on one or more next predetermined transmission cycle.After receiving status report, carries out by receiver re-transmission at transmitter.Yet, but the re-transmission in the execution in step 825, and do not consider the reception of the status report of relevant AMD PDU.This is because as mentioned above, receiver can not identify losing of AMD PDU.

Retransmit several times because transmitter will have the AMD PDU of the poll bit of setting up, thus receiver can receive have the poll bit of setting up AMD PDU several times.Yet, because preferably only delivery status report once, so in the short relatively time, receive identical AMDPDU several times the time when receiver with poll bit of setting up, its only delivery status report once.

Fig. 9 is the flow chart according to the exemplary operations of the receiver of the first embodiment of the present invention.As described below, the control unit of receiver monitors the AMD PDU that is received, so that determined whether to take place because the status report of poll bit triggers.

When receiver received the AMD PDU with poll bit of setting up in step 905, in step 910, receiver determined whether the AMD PDU that is received is the AMD PDU that retransmits.Can be by realizing that relatively this determines between the sequence number of the sequence number of the current AMD PDU that receives and the AMD PDU that most recent receives.Provide more detailed description below.

When receiver had received the AMD PDU with poll bit of setting up, receiver was stored in the sequence number of this AMDPDU in the V parameter (X).After this, when receiving the AMD PDU with poll bit of setting up, receiver compares the sequence number of the AMD PDU that receives and the value among the V (X).When two values were identical, receiver determined that the AMD PDU that is received is the AMD PDU that retransmits.When two values not simultaneously, receiver determines that the AMD PDU received is not the AMD PDU that retransmits.When the AMD PDU that is received was not the AMD PDU that retransmits, receiver was updated to V (X) sequence number of the AMD PDU of new reception.

When the AMD PDU that is received was not the AMD PDU that retransmits, receiver advanced to step 915, and at this, receiver generates and reports to the transmitter delivery status.On the contrary, when the AMD PDU that is received was the AMD PDU that retransmits, receiver advanced to step 920, and at this, receiver is ignored the poll bit of this AMD PDU, and not delivery status report.

Second example embodiment

According to second embodiment of the invention, after the RLC PDU that receiver was not stored receiver in the process scheduled time is reconstructed into RLC SDU, structure and delivery status report.In this process, this scheduled time, it can be determined by test or emulation corresponding to the time interval of enough transmitting a RLC SDU.

Figure 10 is the block diagram that is used for diagram exemplary method according to a second embodiment of the present invention, that be used to handle RLC PDU.

With reference to Figure 10, transmitter 1005 is divided into three

RLC PDU

1015,1020 and 1025 from more high-rise reception RLC SDU 1010 with RLC SDU 1010, and they are stored in the buffer.For example, RLC PDU 1015 has sequence number x, and RLC PDU 1020 has sequence number (x+1), and RLC PDU 1025 has sequence number (x+2).Transmitting RLC PDU[x] 1015 and RLC PDU[x+1] after 1020, transmitter 1005 is RLC PDU[x+2] 1025 poll bit is set, transmit RLC PDU[x+2 then] 1025.For example, suppose RLC PDU[x+2 as last PDU of in buffer, storing] 1025 during transmitting, it loses.

Receiver 1040 receives RLC PDU[x] 1017 and RLC PDU[x+1] 1022.When receiver has received RLC PDU[x] 1017 the time, receiver 1040 starts timers, and be used to generate status report and trigger.After this, when receiver 1040 receives RLC PDU[x+1] 1022 the time, receiver 1040 restarts timer.Particularly, timer restarts the timer that comprises the steps: in the shut-down operation, this timer of initialization, and then operation timer.When receiving RLC PDU[x+1] when not receiving have sequence number next RLC PDU of (x+2) before time of starting 1022 time is expired, receiver structure and delivery status report 1030.Status report 1030 comprises the information of reception of the PDU of report till the RLC PDU 1022 with sequence number (x+1) of being used for.When receiving status report, transmitter 1005 is recognized have sequence number the losing of RLC PDU 1025 of (x+2), and retransmits the RLC PDU 1035 with sequence number (x+2).

Figure 11 is the flow chart that is used for diagram example timer control operation according to a second embodiment of the present invention.As described below, the control unit of receiver monitors the AMD PDU that is received, management VR (H) and VR (R), and control timer.

With reference to Figure 11, in step 1105, receive AMD PDU.In step 1110, whether the sequence number of the definite AMD PDU that is received of receiver is less than VR (H).When the sequence number of the AMD PDU that is received during less than VR (H), receiver advances to step 1115.When the sequence number of the AMD PDU that is received during more than or equal to VR (H), receiver advances to step 1130.

In step 1115, storage AMD PDU makes AMD PDU that is received and the AMD PDU that has stored to store according to the order of their sequence numbers on the appropriate location of receiver in buffer.In step 1120, if can come reconstruct RLC SDU by using the AMD PDU in reception buffer, store, receiver reconstruct RLC SDU and send to the RLC SDU of reconstruct more high-rise then.Then, in step 1125, receiver is waited for and is received next AMD PDU.At this moment, do not stop not restart timer yet.

In step 1130, if timer moves, then receiver cushions the AMD PDU that is received and stops this timer according to the sequence number of AMD PDU in reception buffer.In step 1135, receiver determines whether and can come reconstruct RLC SDU by at least a portion of using the AMD PDU that stores in reception buffer.If can reconstruct RLC SDU, then receiver advances to step 1145.On the contrary, if can not reconstruct RLC SDU, then receiver advances to step 1140.In step 1140, receiver initialization and restart timer advances to step 1125 then, and in step 1125, receiver is waited for next AMD PDU.

In step 1145, receiver comes reconstruct RLC SDU by the AMD PDU that stores in the reception buffer that uses the AMD PDU that receives comprising, determines whether remain the AMD PDU that a part is received then in reception buffer.When AMD PDU that a residue part in reception buffer is received, receiver advances to step 1150, and in step 1150, the receiver operation timer advances to step 1155 then, and in step 1155, receiver is sent to the RLC SDU of reconstruct more high-rise.When not remaining the AMD PDU that is received in reception buffer, receiver directly advances to step 1155, and in step 1155, receiver is sent to the RLC SDU of reconstruct more high-rise.Then, in step 1125, receiver is waited for and is received next AMD PDU.

Even also guarantee normal running when comprising a plurality of RLC SDU as an AMD PDU, step 1145 is necessary.Promptly, when the AMD PDU that is received comprises RLC SDU[x] decline and RLC SDU[y] start-up portion, be necessary operation timer, even so that in complete reconstruct inspection RLC SDU[x] also check RLC SDU[y afterwards] and the arrival or the reception of AMD PDU of back.On the contrary, when the AMDPDU that is received includes only RLC SDU[x] decline and by using the AMD PDU the received RLC SDU[x that come reconstruct] time, do not lose RLC SDU[x because this situation is hinting] last AMDPDU, so needn't operation timer.

As shown in figure 11, receiver all starts or stops timer when receiving AMD PDU, and transmits status report on the overdue time point of timer.

Figure 12 is the block diagram that is used for diagram exemplary operations according to a second embodiment of the present invention.

With reference to Figure 12, transmitter 1205 has two RLC SDU that will transmit, and comprises RLC SDU[x] 1215 and RLC SDU[y] 1220, they are divided into 6 the

AMD PDU

1225,1230,1235,1240,1245 and 1250 that have sequence number 1 to 6 respectively.For example, suppose that among 6 AMD PDU 1225 to 1250, the

AMD PDU

1235 and 1250 with

sequence number

3 and 6 fails to arrive receiver 1210, and has lost.Receive AMD PDU[1 at receiver 1210] time time point on, VR (H) is 1.Receiving AMDPDU[1] 1225 o'clock, receiver 1210 starts timers, and VR (H) is updated to 2.

When receiving AMD PDU[2 with the sequence number that equals VR (H)] 1230 the time, receiver 1210 is updated to 3 with VR (H), stops timer, and determines whether to exist reconfigurable RLC SDU, as the step 1130 of Figure 11 and 1135 performed.Because there is not reconfigurable RLC SDU,, and wait for the arrival of next AMD PDU so receiver 1210 restarts timer.

When receiving AMD PDU[4 with sequence number bigger than VR (H)] 1240 the time, receiver 1210 is determined the PDU that existence do not receive, and delivery status report (not shown).Based on AMD PDU[4] 1240, VR (H) is updated to 5.The status report that is transmitted comprise be used for reporting AMD PDU[3] the information of failure of reception.In addition because this situation corresponding to the situation of sequence number more than or equal to VR (H), so receiver 1210 stops timer, and determines whether to exist reconfigurable RLC SDU, as the step 1130 of Figure 11 and 1135 performed.Because there is not reconfigurable RLC SDU, receiver 1210 restarts timer.

When receiving AMD PDU[5 with the sequence number that equals VR (H)] time, receiver 1210 stops timer, and determines whether to exist reconfigurable RLC SDU, as the step 1130 of Figure 11 and 1135 performed.Because there is not reconfigurable RLC SDU,, and wait for the arrival of next AMD PDU so receiver 1210 restarts timer.Receiver 1210 is updated to 6 with VR (H).

In response to status report, transmitter 1205 retransmits AMD PDU[3] 1255.Then, receiver 1210 receives the AMD PDU[3 that has less than the sequence number of VR (H)] 1255, carry out the operation of the step 1115 to 1125 of Figure 11 then.At this moment, because can be by using RLC PDU[1], RLC PDU[2] and RLC PDU[3] come reconstruct RLC SDU[x], so receiver 1210 is with the RLC SDU[x of reconstruct] be sent to more high-risely, and wait for the arrival of next AMD PDU.

Timer expires at time point 1260 places, because it is receiving AMD PDU[5] be not stopped after 1145 o'clock starting.Like this, according to expiring of timer, receiver 1210 sends status report 1265 to transmitter 1205.Status report 1265 comprise be used for reporting AMD PDU[6] information of the failure of 1250 reception.Thereby transmitter 1205 is recognized and has been lost AMD PDU[6] 1250, and retransmit AMD PDU[6] 1270.

According to aforesaid embodiments of the invention, even when last PDU that stores in the buffer of transmitter loses during it transmits, receiver also can recognize this and lose, and loses the delivery status report for this, makes transmitter can overcome the re-transmission mistake apace.

Although illustrate and described embodiments of the invention with reference to specific example embodiment of the present invention, but it will be appreciated by those skilled in the art that, the modification of various forms and details can be carried out to it, and the spirit and scope of the present invention that are defined by the following claims can be do not broken away from.

Claims

One kind in mobile communication system request be used to retransmit the method for the status report of control, this method comprises the steps:

(1), SDU is divided into a plurality of Packet Data Units (PDU) from more high-rise reception Service Data Unit (SDU);

(2) for last PDU among the described PDU is provided with poll bit, described poll bit solicited status report; And

(3) repeat to transmit described last PDU from sender to receiver with the poll bit that has been provided with, and no matter whether exist retransmitting the request of described last PDU.
2. the method for claim 1, wherein said SDU comprises Radio Resource control (RRC) message, described Radio Resource control (RRC) message comprises the control information of rrc layer.
3. method as claimed in claim 2, wherein said last PDU comprises the rearmost data that mark off from RRC message.
4. the method for claim 1, wherein said status report comprises:

Be desirably in the sequence number of the PDU that receives on the time point that transmits this status report; And

Being identified as is sequence number at the PDU that transmits the unit that does not receive on the time point of this status report.
5. the method for claim 1, wherein step (1) comprises the steps:

SDU cut apart, splices or be filled to data with pre-sizing; And

Add in following at least one to described data with pre-sizing: data/control bit field, sequence number field, be used to indicate whether the poll bit field of wanting solicited status to report, and the length indicator of indicating the end position of the SDU that comprises among the corresponding PDU, construct corresponding PDU thus.
6. the method for claim 1, wherein said last PDU comprises the rearmost data that mark off from SDU.
7. the method for claim 1, wherein said last PDU is included in the PDU of the last scheduling of storing in the buffer.
One kind in the Radio Link of mobile communication system control (RLC) layer request be used to retransmit the equipment of the status report of control, this equipment comprises:

Packet Data Unit (PDU) building block is used for from more high-rise reception Service Data Unit (SDU), and SDU is divided into a plurality of PDU;

Transmit buffer, be used for storing PDU at buffer;

Poll bit is provided with piece, is used to last PDU among the described PDU that is stored in the buffer that poll bit is set, described poll bit solicited status report; And

Cryptographic block is used for described last PDU with the poll bit that has been provided with is encrypted, and described last PDU is sent to receiver,

Wherein repeat to transmit described last PDU from sender to receiver, and no matter whether exist retransmitting the request of described last PDU.
9. equipment as claimed in claim 8, wherein said SDU comprise Radio Resource control (RRC) message, and described Radio Resource control (RRC) message comprises the control information of rrc layer.
10. equipment as claimed in claim 9, wherein said last PDU comprises the rearmost data that mark off from RRC message.
11. equipment as claimed in claim 8, wherein said status report comprises:

Be desirably in the sequence number of the PDU that receives on the time point that transmits this status report; And

Being identified as is sequence number at the PDU that transmits the unit that does not receive on the time point of this status report.
12. equipment as claimed in claim 8, wherein said PDU building block comprises:

Cut apart/splicing block, be used for SDU cut apart, splices or be filled to data with pre-sizing; And

The RLC head adds piece, be used for adding following at least one: data/control bit field, sequence number field, be used to indicate whether the poll bit field of wanting solicited status to report to described data with pre-sizing, and the length indicator of indicating the end position of the SDU that comprises among the corresponding PDU, construct corresponding PDU thus.
13. equipment as claimed in claim 8, wherein said last PDU comprises the rearmost data that mark off from SDU.
14. equipment as claimed in claim 8, wherein said last PDU is included in the PDU of the last scheduling of storing in the buffer.
15. a method that transmits the status report be used to retransmit control in mobile communication system, this method comprises the steps:

(1) pass through more low layer, receive PDU from transmitter, the PDU that is received has set poll bit, this poll bit solicited status report;

(2) determine whether the PDU that is received is the PDU that retransmits;

(3) when the PDU that is received is the PDU that retransmits, ignore the poll bit of the PDU that is received, and not delivery status report; And

(4) when the PDU that is received is not the PDU that retransmits, the delivery status report in response to poll bit.
16. method as claimed in claim 15, wherein said status report comprises:

Be desirably in the sequence number of the PDU that receives on the time point that transmits this status report; And

Being identified as is sequence number at the PDU that transmits the unit that does not receive on the time point of this status report.
17. method as claimed in claim 15, wherein step (2) comprises the steps:

When the PDU that is received has the sequence number that equates with most recent sequence number that receive, that have the PDU of set poll bit, determine that the PDU that is received is the PDU that retransmits.
18. method as claimed in claim 15, when also comprising the steps: to work as the PDU that is received and not being the PDU that retransmits, with the sequence number of the PDU that received be stored as that most recent receives, have the sequence number of the PDU of set poll bit.
19. an equipment that transmits the status report be used to retransmit control in mobile communication system, this equipment comprises:

Decryption block is used for receiving PDU by low layer more from transmitter, and the PDU deciphering to being received, and the PDU that is received has set poll bit, this poll bit solicited status report;

Reception buffer is used to store the PDU through deciphering, up to described PDU through deciphering is reconstructed into corresponding SDU;

Controll block when it is worked as the PDU that is received and is the PDU that retransmits, is ignored the poll bit of the PDU that is received, and delivery status report, and when working as the PDU that is received and not being the PDU that retransmits, the delivery status report in response to poll bit; And

Transmission block is used for status report is sent to described transmitter.
20. equipment as claimed in claim 19, wherein said status report comprises:

Be desirably in the sequence number of the PDU that receives on the time point that transmits this status report; And

Being identified as is sequence number at the PDU that transmits the unit that does not receive on the time point of this status report.
21. equipment as claimed in claim 19, wherein said reception buffer is configured to:

Check the sequence number of the PDU that is received; With

When the sequence number of the PDU that is received equals the sequence number of most recent PDU that receive, that have set poll bit, determine that the PDU that is received is the PDU that retransmits.
22. equipment as claimed in claim 21, wherein, when the PDU that is received is not the PDU that retransmits, with the sequence number of the PDU that received be stored as that most recent receives, have the sequence number of the PDU of set poll bit.
23. a method that transmits the status report be used to retransmit control in mobile communication system, this method comprises the steps:

Receive protocol Data Unit (PDU) by low layer more from transmitter;

Whether the sequence number of definite PDU that is received is greater than the maximum sequence number in the sequence number of the PDU that has received;

When the sequence number of the PDU that is received during greater than described maximum sequence number, stop to be used to produce the timer that status report triggers, and determine whether and to come the complete Service Data Unit of reconstruct (SDU) by using at least a portion among the PDU that in reception buffer, stores;

When can not reconstruct complete SDU, restart described timer; And

When described timer expires, status report is sent to transmitter.
24. method as claimed in claim 23, wherein said status report comprises:

Be desirably in the sequence number of the PDU that receives on the time point that transmits this status report; And

Being identified as is sequence number at the PDU that transmits the unit that does not receive on the time point of this status report.
25. method as claimed in claim 23 also comprises the steps:

When can reconstruct RLC SDU, come reconstruct RLC SDU by using at least a portion among the PDU that in reception buffer, stores;

After reconstruct RLC SDU, determine in reception buffer, whether to remain the PDU that a part receives;

When PDU that a residue part in reception buffer receives, restart timer, and be sent to described RLC SDU more high-rise; And

When PDU that a residue part in reception buffer receives, described RLC SDU is sent to more high-rise, and do not restart described timer.
26. method as claimed in claim 23 also comprises the steps:

When the sequence number of the PDU that is received is not more than maximum sequence number in the sequence number of the PDU that has received, waits for receiving next PDU, and do not stop or restarting described timer.
27. an equipment that transmits the status report be used to retransmit control in mobile communication system, this equipment comprises:

Decryption block is used to receive and decipher by low layer more and the protocol Data Unit (PDU) that transmits from transmitter;

Reception buffer is used to store the PDU through deciphering, up to described PDU through deciphering is reconstructed into corresponding SDU; And

Controll block, its sequence number that is configured to work as the PDU that is received is during greater than described maximum sequence number, stop to be used to produce the timer that status report triggers, determine whether then and can come the complete Service Data Unit of reconstruct (SDU) by using at least a portion among the PDU that in reception buffer, stores, when can not reconstruct complete SDU, restart described timer, and when described timer expires, status report is sent to transmitter.
28. equipment as claimed in claim 27, wherein said status report comprises:

Be desirably in the sequence number of the PDU that receives on the time point that transmits this status report; And

Being identified as is sequence number at the PDU that transmits the unit that does not receive on the time point of this status report.
29. equipment as claimed in claim 27, wherein said controll block is configured to:

When can reconstruct RLC SDU, come reconstruct RLC SDU by using at least a portion among the PDU that in reception buffer, stores;

After reconstruct RLC SDU, determine in reception buffer, whether to remain the PDU that a part receives;

When PDU that a residue part in reception buffer receives, restart timer, and be sent to described RLC SDU more high-rise; And

When PDU that a residue part in reception buffer receives, described RLC SDU is sent to more high-rise, and do not restart described timer.
30. equipment as claimed in claim 27, wherein said controll block is configured to:

When the sequence number of the PDU that is received is not more than maximum sequence number in the sequence number of the PDU that has received, waits for receiving next PDU, and do not stop or restarting described timer.