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1、2|Presentation Title|Month 2006,1,B8&B9 NC2,NC2,NC2,NC2,NC2,NC2,NC_Reporting _Period_T,MS PTM,NC_Reporting _Period_T,Networl control order,NC2,NC2,NC2,NC2,NC2相关参数NC2重选参数类似于通话切换设定通过调整相应控制小区重选条件的参数的门限值,NC2可减少不必要的小区重选次数,NC2,无线接入,A,B,C,D,NC2模式 只有1个小区重选 给手机用户提供了更好的GPRS吞吐量,NC0模式在分组传输模式下,有3个小区重选,B8目标:有效减少小
2、区重选次数(通过NC2的引入),GPRS传输阶段,13|Presentation Title|Month 2006,2,Enhanced Transmission Resource Management(B9),Catalog,M-EGCH Statistical Multiplexing Dynamic Abis Allocation,15|Presentation Title|Month 2006,2.1,M-EGCH Statistical Multiplexing,M-EGCH Statistical Multiplexing,An M-EGCH link(Multiplexed En
3、hanced GPRS CHannel)is a bi-directional link established between the MFS and the BTS.An M-EGCH link is a set of 16k GCH channels.An M-EGCH link is defined per TRX.The M-EGCH link of a TRX is necessary:To carry TBF traffic and PACCH signalling when TBFs are established on some PDCHs of the TRX,To car
4、ry signalling messages when MPDCHs are defined on the TRX,To carry UL signalling messages after one-UL-block allocation(UL two-phase access),To carry some BTS-MFS signalling.,M-EGCH Statistical Multiplexing,M-EGCH Statistical Multiplexing,M-EGCH Statistical Multiplexing,Reduction of the Abis and Ate
5、r consumptionResources are used in a more efficient way:Instantaneous reaction to radio variations(MCS variations).Example:No more TBF maximum MCS reduction is needed.The resources not used by delayed DL TBFs,extended UL TBFs,are used by other TBFs.,M-EGCH Statistical Multiplexing,统计复用下,GCH的数量不再是取整的
6、,M-EGCH Statistical Multiplexing,In B9:The size of an M-EGCH link(associated to a TRX)can be dynamically decreased or increased.The algorithms to dynamically decrease or increase the size of an M-EGCH link correspond to the Dynamic Abis allocation.,M-EGCH Statistical Multiplexing,Example:One TBF:4 P
7、DCH used MCS-7Not use Statistical Multiplexing 1 PDCH=4 GCH Total GCH expenditure:16 GCHUse Statistical Multiplexing 1 PDCH=3.49 GCH Total GCH expenditure:14 GCH,Saving12.5,23|Presentation Title|Month 2006,2.2,Dynamic Abis Allocation,Dynamic Abis Allocation,Dynamic Abis Allocation,In B8,the followin
8、g Abis nibbles were“wasted”:,Dynamic Abis Allocation,In B9,the following Abis nibbles are usable for PS traffic:The basic Abis nibbles mapped to a RTS currently available for PS traffic(see“Autonomous Packet Resource Allocation feature to know the list of those RTSs)or mapped to a RTS used as MPDCH.
9、Example:,Dynamic Abis Allocation,The“bonus”basic Abis nibbles currently used for BCCH or static SDCCH channels:The list of“bonus”Abis nibbles depends on the cell configuration.All the extra Abis nibbles of the BTS:A number of 64k extra Abis TSs is defined for each BTS by O&M(N_EXTRA_ABIS_TS).The lis
10、t of extra Abis TSs of a BTS is provided by the BSC to the MFS.,Dynamic Abis Allocation,The basic Abis nibbles mapped on a RTS allocated to MFS can be used in the M-EGCH link of any TRX of the CELL.The extra Abis nibbles can be used in the M-EGCH link of any TRX of the BTS.The“bonus”Abis nibbles can
11、 be used in the M-EGCH link of any TRX of the BTS.,Dynamic Abis Allocation,Due to Dynamic Abis allocation,new messages have to be sent to the BTS to notify each TRE which Abis nibbles are associated.Those messages are sent via GSL and RSL interfaces.The following scenarios are therefore modified:GCH
12、 establishment.GCH release.New scenario appear to distribute GCH resources:Intra-cell GCH pre-emption:between TRXs of a cellInter-cell GCH pre-emption:between cells of a BTS,30|Presentation Title|Month 2006,3,Extended Uplink TBF Mode(B9),B9 Extended UL TBF Introduce,The aim of this feature is to ext
13、end the duration of the UL TBF in order:To quickly restart data transmission in UL if higher layers in the MS deliver new data,without having to re-establish a new UL TBF,after the countdown procedure has started.To maintain the UL TBF established,some time after the last block(CV=0)has been acknowl
14、edged by the network.This feature allows improving access time to the GPRS/EGPRS network.It also improves the throughput in some cases.The feature applies only for R4 MS,B9 Extended UL TBF Introduce,MS and BSS capability The MS is aware of the BSS capability by the NW_EXT_UTBF parameter that is broa
15、dcast on either BCCH(SI13).A MS indication indicating support of GERAN Feature Package 1 in the Mobile Station Classmark 3 IE,the MS Radio Access Capability IE and the MS Radio Access Capability 2 IE supports the extended uplink TBF mode.,B9 Extended UL TBF Introduce,Functional descriptionEnable or
16、disable the Extended uplink TBF mode through an O&M parameter,EN_EXTENDED_UL_TBF.And configure an inactivity period as duration of extended uplink TBF mode,T_MAX_EXTENDED_UL.Indicate to MS that the network supports the extended uplink TBF mode.The MS is aware of the BSS capability by the NW_EXT_UTBF
17、 parameter.So the MS is always aware of the BSS capability before establishing an Uplink TBF.On the contrary the BSS does not always know the MS capability when the first Uplink TBF is established at the beginning of a session.Detect whether or not a given MS supports the Extended Uplink TBF Mode.Th
18、e MS radio access capability is received at downlink TBF establishment in the first downlink PDU received on Gb interface.In case of cell reselection for an uplink transfer,some time TBF may elapse before a Downlink PDU is received.“Radio Access Capability Update”procedure is used to obtain the info
19、rmation.Apply the Normal release mode if the MS does not support the Extended Uplink TBF Mode or if the BSS does not know MS capability.Switch to Extended Uplink TBF Mode when a MS is detected to support the feature,when the Radio Access Capabilities are received during the UL transfer.Maintain to U
20、SF scheduling an uplink TBF during the inactivity period,while the MS has no data to transmit,and maintain the reception of uplink RLC data block as long as the uplink TBF is in extended phase.6.Release the uplink TBF upon timer T_max_extended_UL expiry,B9 Extended UL TBF Introduce,.If MS support Ex
21、tended UL TBF mode is known.Entering the Extended uplink phase When the MS begins to run out of LLC data,it begins the countdown normally.When the BSS receives the last RLC block(CV=0),and if all the previous blocks have been correctly received,the BSS sends a Packet Uplink Ack/Nack with FAI set to
22、0,with the SSN incremented like for an active TBF(SSN=last received BSN+1).All RLC numbering variables are kept as TBF was still active.The uplink TBF is now extended and will not be released by the mobile.The BSS starts the timer T_max_extended_UL to monitor the maximum duration of the extended pha
23、se.,B9 Extended UL TBF Introduce,BSS behavior during the Extended uplink phase,The BSS continues to schedule USF,so that the MS is able to resume an uplink transfer when required.While the UL TBF is in extended phase,the reception of an uplink dummy block from the MS,shall not cause the N3101 counte
24、r to be incremented in the BSS.Only invalid block reception increments N3101.While the UL TBF is in extended phase,the reception of an uplink dummy block from the MS shall not cause the N_UL_dummy counter to be incremented.,B9 Extended UL TBF Introduce,T_max_extended_UL expiryThe network ends the TB
25、F permanently by sending a Packet Uplink Ack/Nack with FAI=1 and polling.When receiving PUAN with FAI=1 and polling,the MS sends the Packet Control Ack in response to polling,and then aborts the uplink TBF.When the timer T_max_extended_UL expires,the BSS shall wait for all the radio blocks correspon
26、ding to already transmitted USF,before transmitting FAI=1.,If the radio blocks corresponding to the last scheduled USF carry RLC data block,not the Dummy block,then the BSS shall restart the uplink TBF.,B9 Extended UL TBF Introduce,Principle to design USF schedulingUSF for extended mode are schedule
27、d only on the PDCH,which carries PACCH.IF the PDCH supports uplink TBF,which all are in extended mode,Then,if flag EN_FAST_USF_UL_EXTENDED=enablethen the throughput in radio blocks is equally shared between MS(round robin of one RLC block per MS).So USF are scheduled as follows:One MS in extended mo
28、de on PACCH:USF scheduled every 20msTwo MS in extended mode on PACCH:USF scheduled every 40ms n MS in extended mode on PACCH:USF scheduled every n x 20mELSE(if the flag EN_FAST_USF_UL_EXTENDED is disabled or if the PDCH supports at least one MS which is in UL transfer)A polling period T_extended_UL_
29、TBF_POL,is used for all MS in extended phase.A default value is 200ms.The remaining bandwidth is used for MS in transfer.,OMC-R Parameters,Example for WAP Access,The WAP access time is estimated with and without Extended UL TBF,for an MS which is already GPRS attached.The time is estimated as follow
30、s:for an uplink message:MS response time+UL transmission time on the radio interface+UL TBF establishment for a downlink message:Network response time+DL transmission time on the radio interface+DL TBF establishmentMS type is GPRS with 3 PDCH downlink and 1 PDCH uplinkInvoke Ack is not counted for a
31、ccess time,because the user can see the page as soon as the invoke reply is received,Example for WAP Access,Example for WAP Access,42|Presentation Title|Month 2006,4,Enhanced Packet Cell Reselection(B9),Introduction,减小packet cell reselection 过程服务损耗(支持NC0和NC2)Network Assisted Cell Change Procedures(N
32、ACC):手机能在服务小区中获得目标小区的(P)SI消息 Only for R4 MS.Packet(P)SI Status procedure:允许手机在没有读取完整新小区的(P)SI 消息前,就能接入新小区,Mainly for R4 MS.,Network Assisted Cell Change,NACC NC2,NACC NC0,Packet(P)SI Status,Packet PSI Status,Packet SI Status,Content,Network Assisted Cell Change(NACC),服务小区的NACC过程包含两个步骤:CCN mode proce
33、dure(Cell Change Notification)当数据传输模式下发生小区重选时,手机将通知网络侧,延缓小区选择过程,让BSC决定是否进行小区系统消息发送过程(Cell System Information distribution)Cell System Information distribution该过程是使在数据传输模式下(PTM)手机得到目标小区的系统消息,使小区重选完成后能进行initial packet access过程。这些信息是在小区重选完成前,通过原服务小区发送给手机的。,Network Assisted Cell Change-NC0(1/2),当EN_NACC
34、=enable,NACC功能对小区下所有支持GERAN feature package 1 的R4手机开启,T3206监视发送 Packet Cell Change Notification消息.当收到Packet Cell Change Notification消息后,MFS会检查是否这个目标小区是属于同一个BSS,如果发现源小区和目标小区不是同一个BSS,侧网络将直接下发Packet Cell Change Contiune消息,并不发送任何邻小区的系统消息。,Note:The figure above covers the case where there is a PBCCH in t
35、he target cell.When there is no PBCCH channel in the target cell,the same scenario takes place with BSS sends the SI13,SI1 and SI3 messages instead of the PSI14,PSI1 and PSI2 messages.,Network Assisted Cell Change-NC0(2/2),如果是属于同一个BSS,那么RMM将开始T3208的计时器,它主要监视从BSS回发的PCCC消息(Packet Cell Change Continue)
36、,整个过程中接收SI13/SI1/SI3 或者PSI14/PSI1/PSI2 当手机接收了RLC下行发送的所有PACKET NEIGHBOUR CELL DATA,BSS侧将会下发PCCC消息,此时计时器T3208停止,该消息在PACCH消息上发送。需要值得注意的是没有PCA消息来确认PCCC消息,也就是说没有BSS侧没有T_ACK_Wait timer,因为MS已经离开了CCN过程,要么是因为收到了PCCC消息或者是T3208已经超时。当接收到PCCC消息,手机将离开PCN模式,继续NC0的小区重选过程。,Network Assisted Cell Change-NC2(1/2),NC2 c
37、ell reselection execution with Cell System Information Distribution一个上行或者下行的TBF已建立.手机通过PACCH在已分配的UL block发送a Packet Measurement Report消息当接收到Packet Measurement Report后,BSS发现需要触发一次小区重选过程,如目标小区和源小区属于同一个BSS,此时MS将获得邻小区的(P)SI消息 对于所有在该小区PDCH上已经分配TBF的手机,BSS将发送PNCD给MS,包含目标小区packet system infrmation消息,SI13、SI
38、1和SI3 如目标小区无PBCCHPSI14(和SI13有相同的消息)、PSI1和PSI2消息 如目标小区为有PBCCH 当上行和下行的TBF都存在的情况下,PNCD将在下行TBF上发送,Network Assisted Cell Change-NC2(2/2),(5)当所有的PNCD都发送后,BSS通过PACCH在上行或者下行的TBF上发送Packet Cell Change Order消息。如果上下行TBF都存在,那么消息优先在下行TBF上发送 Packet Cell Change Order消息需要确认,消息中包含了目标小区的信道和BSIC 当发送Packet Cell Change O
39、rder消息后,BSS将启动T_ACK_WAIT 来监视确认消息的接收(6)-(7)手机侧当接收到Packet Cell Change Order消息,将在服务小区上释放占有的TBF,然后回确认消息并切换到新的小区,Content,Network Assisted Cell Change,NACC NC0NACC NC2,Packet(P)SI Status,Packet PSI Status,Packet SI Status,Packet(P)SI Status,B9引入的Packet(P)SI status新的功能,它可以使允许手机能够接入一个新的小区,即便此时手机还没有从BCCH信道上获
40、得目标小区完整的系统消息 The Packet(P)SI Status procedure作用于目标小区,当EN_PSI_STATUS EnablePacket PSI Status procedure功能支持从R97、R98、R99到支持GERAN package1的R4标准的手机 Packet SI Status procedure 是R4标准的新功能,从支持GERAN package1的R4手机开始支持,Packet SI Status(1/2),the Packet SI Status procedure,当重选到一个不支持PBCCH小区,并且支持Packet SI Statue(即E
41、N_PSI_STATUS=enable),此时MS能在该小区上立刻请求一个上行的TBF,如果手机已经获得了新小区的SI13、SI3和SI1(如果存在)。然后手机能发送一个cell update或者继续数据传送。手机通过在PACCH上发送PACKET SI STATUS请求BSS提供缺少的系统消息(SI12、SI12bis、SI2ter),Packet SI Status(2/2),当接收到手机请求后,如果下行TBF已经建立或者下行TBF正在建立或者下行TBF即将建立,这时BSS将等待这个下行TBF建立完成,在所有已经分配的下行TBF的PDCH信道上发送所需求的SIs消息给手机。一个监督的tim
42、er(T_PSCD_SCHEDULE_ACK),当开始发送SI消息到手机开始 SI数据被编码在一个或者多个PACKET SERVING CELL DATA消息中,分别发送给手机。当最后一个SI发送给手机后,T_PSCD_SCHEDULE_ACK停止。,Packet PSI Status(1/2),Packet PSI Status procedure,当重选到一个支持PBCCH的小区并且支持Packet PSI Statue(即EN_PSI_STATUS=enable),此时MS能够立刻请求一个上行的TBF,如果手机已经获得了新小区的PSI14、PSI1和PSI2。然后手机能够发送一个cell
43、 update或者继续数据传送 手机通过在PACCH上发送PACKET SI STATUS请求BSS提供缺少的系统消息(PSI13、PSI13bis),Packet PSI Status(2/2),当接收到手机的请求后,如果下行的TBF已经建立或者下行的TBF正在建立或者下行TBF即将建立(下行LLC PDU将被rerouted到一个新的小区),这时BSS将等待这个下行TBF建立完成,在所有已经分配的下行TBF的PDCH信道上发送所需求的PSIs消息给手机,否则PSIs将在分配上行TBF PDCH信道上发送一个监督的timer(T_PSCD_SCHEDULE_ACK)监督发送PSI消息到手机。当最后一个PSI发送给mobile,T_PSCD_SCHEDULE_ACK停止,OMC-R parameters,