GSM-R(GSM-Railway)__第7章-無(wú)線測(cè)量課件

下載文檔

下載文檔到電腦，查找使用更方便還剩頁(yè)未讀，繼續(xù)閱讀>>

侵權(quán)申訴舉報(bào)

1 / 38

此文檔下載收益歸作者所有下載文檔

版權(quán)提示

文本預(yù)覽

常見(jiàn)問(wèn)題

單擊以編輯母版標(biāo)題樣式,單擊以編輯母版文本樣式,第二級(jí),第三級(jí),第四級(jí),第五級(jí),無(wú)線測(cè)量,第7章,無(wú)線測(cè)量第7章,內(nèi)容提要,無(wú)線測(cè)量的基本原理,不連續(xù)傳輸,DTX,無(wú)線測(cè)量的處理方法,算術(shù)平均,加權(quán)平均,標(biāo)準(zhǔn)處理與快速處理,測(cè)量數(shù)據(jù)的丟失處理,內(nèi)容提要無(wú)線測(cè)量的基本原理,距離,質(zhì)量,測(cè)量,判決:越區(qū)切換,功率控制,呼叫清除,處理,信號(hào)強(qiáng)度,一、移動(dòng)通信中對(duì)無(wú)線測(cè)量的要求,距離質(zhì)量測(cè)量判決:越區(qū)切換,功率控制,呼叫清除處理信,判決過(guò)程與參數(shù),判決過(guò)程與參數(shù),處理優(yōu)先級(jí),處理優(yōu)先級(jí),二、無(wú)線測(cè)量的流程,無(wú)線測(cè)量的結(jié)果是判決越區(qū)切換和功率控制的準(zhǔn)則移動(dòng)臺(tái)測(cè)量下行鏈路的信號(hào)強(qiáng)度和信號(hào)質(zhì)量，基站測(cè)量上行鏈路的信號(hào)強(qiáng)度和信號(hào)質(zhì)量移動(dòng)臺(tái)在,測(cè)量報(bào)告,中包含的測(cè)量數(shù)據(jù)：,下行鏈路接收的信號(hào)電平：,RXLEV_DL,下行鏈路接收的信號(hào)質(zhì)量，即誤比特率（,BER）：RXQUAL_DL,下行鏈路相鄰小區(qū)的信號(hào)電平：,RXLEV_NCELL(n),Layer 1 Header,消息中傳輸?shù)臏y(cè)量數(shù)據(jù)：,移動(dòng)臺(tái)與基站的距離,移動(dòng)臺(tái)當(dāng)前使用的功率：,MS_TXPWR,和,MS_TXPWR_CONF,基站計(jì)算的測(cè)量數(shù)據(jù),上行鏈路接收的信號(hào)電平：,RXLEV_UL,上行鏈路接收的信號(hào)質(zhì)量：,RXQUAL_UL,基站當(dāng)前使用的功率：,BS_TXPWR,二、無(wú)線測(cè)量的流程無(wú)線測(cè)量的結(jié)果是判決越區(qū)切換和,無(wú)線測(cè)量過(guò)程描述,無(wú)線測(cè)量過(guò)程描述,無(wú)線測(cè)量的報(bào)告消息,Mobile Measurements,Decision of Mobile Power Control,Call Clearing Indication,Handover Indication,L1M:Layer One Management,BSC,L1M,BTS,TRAFFIC,MANAGEMENT,無(wú)線測(cè)量的報(bào)告消息Mobile MeasurementsDe,D0,D1,D2,D3,D4,D5,D6,D7,A0,A1,A2,A3,-,-,-,D0,D1,D2,D3,D4,D5,D6,D7,A4,A5,A6,A7,-,-,-,A5,A6,A7,D0,D1,D2,D3,D4,D5,D6,D7,A0,-,A1,A2,A3,D0,D1,D2,D3,D4,D5,D6,D7,A4,-,-,-,-,-,-,-,SDCCH/8,(downlink),SDCCH/8,(uplink),235,ms,On SDCCH,1,SACCH message block consists of 4 SACCH TS.,A complete measurement report is sent every 2 x 235=470 ms.,Di:data conveyed on sub-channel i,Ai:SACCH block associated with block Di,三、無(wú)線測(cè)量的報(bào)告周期,D0D1D2D3D4D5D6D7A0A1A2A3-D0D,TCH,TCH,TCH,TCH,SACCH,Idle,On TCH,120,ms,1,SACCH message block consists of 4 SACCH TS.,A complete measurement report is sent every 4 x 120=480 ms.,12,TCH,12,TCH,.,.,無(wú)線測(cè)量報(bào)告周期,TCHTCHTCHTCHSACCHIdleOn TCH120,無(wú)線測(cè)量數(shù)據(jù)處理方法的三要素(對(duì)象、算法、時(shí)間),:,需要對(duì)功率電平、通信質(zhì)量、鄰小區(qū)評(píng)估、距離,進(jìn)行平均處理；,兩種平均算法：算術(shù)平均(標(biāo)準(zhǔn))和加權(quán)平均；,規(guī)定每一次平均運(yùn)算的周期。

無(wú)線測(cè)量的三要素,無(wú)線測(cè)量數(shù)據(jù)處理方法的三要素(對(duì)象、算法、時(shí)間):無(wú)線測(cè)量的,RXLEV,RXLEV:Received signal level averaged over a complete SACCH block period and,coded onto 6 bits(0-63),RXLEV in dBm=-110+RXLEV=RXLEV ranges between-110 and-47 dBm,四、無(wú)線測(cè)量的數(shù)據(jù)類(lèi)型,1、RXLEV(,信號(hào)電平),RXLEVRXLEV:Received signal l,RXQUAL,表示的是一個(gè)測(cè)量報(bào)告周期內(nèi)接收的信號(hào)質(zhì)量的平均值，長(zhǎng)度為3比特，范圍從0到7,2、,無(wú)線通信質(zhì)量的測(cè)量,RXQUAL,與誤比特率的對(duì)應(yīng)關(guān)系,RXQUAL,誤比特率,平均值,0,12.8%,18.10%,誤比特率與,RXQUAL,（,i,）,的換算公式為：,平均誤比特率,=2,1/2,2,i,0.1%,RXQUAL表示的是一個(gè)測(cè)量報(bào)告周期內(nèi)接收的信號(hào)質(zhì)量的平均值,TS1,3,TS,Timing Advance,d=,2 x,t,TDMA Frame,F,The compensation of the propagation delay is by the advancing MS transmission time of,d.,The BTS continuously measures time offset between the burst schedule and the received burst.,TS1,TS1,TS1,Without TA,TS expected,by the BTS,3,TS-,d,TS2,Overlapping,TS2,TS2,TS2,Anticipation of,the MS transmission,t,3、無(wú)線傳播時(shí)延和定時(shí)提前量的測(cè)試,TS13 TSTiming Advance d=2 x,處于專(zhuān)用模式,The BTS permanently evaluates,Timing Advance TA for Frame Alignment.,TA:0.63,The BTS permanently evaluates MS_BS Distance used as a,criterion for HO and Call Clearing.,MS_BS DISTANCE(m)=TA_TO_M*Timing advance TA,TA_TO_M=T*v/(2*BP),with:,T=Duration of one timeslot(secs)=3/5200,577 s,BP=No.of bit periods in one timeslot=156.25,v=velocity of light,MS_BS DISTANCE range=0-63,定時(shí)提前量和,MS-BS,距離數(shù)據(jù)的描述方法,處于專(zhuān)用模式The BTS permanently eval,MS_TXPWR and MS_TXPWR_CONF are expressed as a power control level from the maximum TXPWR possible in the band:,The Power Control Levels are not converted into dBm for the storage,BS_TXPWR and BS_TXPWR_CONF are expressed as a power control level,in the range 0-15(not in dBm),from the maximum TXPWR allowed for the BTS through,bsTxPwrMax,parameter.,功率控制電平,Power Control Level,Nominal Output Power(900 MHz),0,43.41 dBm,1,41.39 dBm,2,39.37 dBm,.,MS_TXPWR and MS_TXPWR_CONF are,空閑,空閑,TC25,TC24,復(fù)幀,i,復(fù)幀,i+1,臨近,BTS,TS0,TS0,監(jiān)視窗口,TS0,TS0,TS0,在鄰近小區(qū)的,BCCH,頻率上測(cè)量,TC1,處于當(dāng)前小區(qū)的移動(dòng)臺(tái),TC25,TC24,TC1,五、對(duì)鄰小區(qū)的監(jiān)視和測(cè)量,下行鏈路,上行鏈路,空閑空閑TC25TC24復(fù)幀 i復(fù)幀 i+1臨近BTSTS,減少干擾,延長(zhǎng)手機(jī)電池工作時(shí)間,a,a,b,b,小區(qū),b,小區(qū),a,六、不連續(xù)傳輸,減少干擾延長(zhǎng)手機(jī)電池工作時(shí)間aabb小區(qū) b小區(qū) a六、不連,采用,DTX,不采用,DTX,下行鏈路測(cè)量報(bào)告,RXLEV_SUB_SERVING_CELL,RXQUAL_SUB_SERVING_CELL,RXLEV_FULL_SERVING_CELL,RXQUAL_FULL_SERVING_CELL,上行鏈路測(cè)量報(bào)告,RXLEV_SUB_UP,RXQUAL_SUB_UP,RXLEV_FULL_UP,RXQUAL_FULL_UP,BTS,測(cè)量,RxLevUL_SUB,RxLevUL_FULL,RxQualUL_SUB,RxQualUL_FULL,BTS,設(shè)置,DTX,標(biāo)志,DTX_USED,或,DTX_NOT USED,MS,測(cè)量,RxLevDL_SUB,RxLevDL_FULL,RxQualDL_SUB,RxQualDL_FULL,MS,設(shè)置,DTX,標(biāo)志,DTX_USED,或,DTX_NOT USED,不連續(xù)傳輸對(duì)無(wú)線測(cè)量的影響,采用DTX 不采用DTX 下行鏈路測(cè)量報(bào)告RXLEV_SUB,七、標(biāo)準(zhǔn)平均,七、標(biāo)準(zhǔn)平均,算術(shù)平均,算術(shù)平均是對(duì)最新的,XXHreqave,個(gè)數(shù)據(jù)(,L1M,收到的測(cè)量結(jié)果中的數(shù)據(jù))進(jìn)行計(jì)算，并在收到每個(gè)新的測(cè)量報(bào)告時(shí)就計(jì)算一次，即使目前并不需要這些值，也需要計(jì)算。

算術(shù)平均算術(shù)平均是對(duì)最新的XXHreqave個(gè)數(shù)據(jù)(L,加權(quán)平均,加權(quán)平均是對(duì),XXHreqt,個(gè)數(shù)據(jù)(測(cè)量值或算術(shù)平均值)進(jìn)行計(jì)算，并且只有當(dāng)需要的時(shí)候才會(huì)計(jì)算一次，即只有當(dāng)距離、質(zhì)量或電平的平均值需要與判決門(mén)限進(jìn)行比較時(shí)才會(huì)計(jì)算它們的加權(quán)平均值每當(dāng),runCallClear,、,runPwrControl,或,runHandOver,出現(xiàn)時(shí)，才會(huì)計(jì)算加權(quán)平均加權(quán)平均加權(quán)平均是對(duì)XXHreqt個(gè)數(shù)據(jù)(測(cè)量值或算術(shù),算術(shù)平均和加權(quán)平均相結(jié)合,算術(shù)平均和加權(quán)平均相結(jié)合,八、短平均(快速處理),八、短平均(快速處理),TIME,權(quán)重,舉例,:,XXHreqave,=4,XXHreqt,=3,Weights,=45,30,25,25,30,45,PAST,12 SACCH,塊,6 s,PRESENT,TIME,T0,HREQAVE x HREQT,WEIGHTING IS A WAY OF GIVING MORE IMPORTANCE TO,PRESENT OVER PAST MEASUREMENTS,標(biāo)準(zhǔn)處理,PRESENT,PAST,No handover decision before Hreqave*Hreqt Level and Quality measurements and rxNCellHreqave neighboring cells measurements.,TIME權(quán)重舉例:XXHreqave=4253045P,標(biāo)準(zhǔn)處理不能滿足特定的需要,HOW?,Arithmetic averaging on less measurements,SHORTER AVERAGES,WHY?,To enable a quicker handover decision,(HO on PBGT only),WHAT?,Level on the current+neighboring cells,WHO?,Fast moving MS,slow reselection process,MS turning at a street corner,MS entering a tunnel,SHORTER AVERAGES ARE USED。

點(diǎn)擊閱讀更多內(nèi)容