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wu xian ju yu wang HiperLAN/2 biao zhun zong shu

2008-05-31 05:59:06 编辑來源:互联网 评论
 
 
 
本文为【无线局域网HiperLAN/2标准综述】的拼音翻译版
  zhai yao : gai kuang jie shao le HiperLan/2 biao zhun , yi ji lian lu he xi tong de xing neng 。
  yao hai ci : wu xian ju yu wang (WLAN) wu xian jie ru kuan dai
  yi 、 gai shu
  wu xian he yi dong tong xin de kuai su fa zhan 、 duo mei ti ying yong de chu xian yi ji Internet jie ru de xu yao dou ci ji zhe wu xian kuan dai jie ru wang luo de jin yi bu kai fa 。 di er dai yi dong wu xian xi tong de gai jin yi ji zheng zai da li kai fa de di san dai wu xian tong xin wang de mu de jiu zai yu shi wang luo neng gou ti gong wu xian xin dao shang zui gao ke da 2Mbps de shun shi yong hu bi te lv , cong er da da ti gao fen zu shu ju he yi dong duo mei ti ying yong 。 tong shi dui yu ju yu wang cai yong yi xie xin de wu xian ji shu shen zhi ke huo de geng gao de shu ju lv 。 qi zhong xin yi dai WLAN ji shu ��HiperLAN/2 biao zhun jiu shi yi li 。
  HiperLAN/2 shi mu qian zui wei wan shan de WLAN xie yi 。 ta de te dian shi : gao su chuan shu 、 mian xiang lian jie 、 zhi chi QoS、 zi dong pin lv pei zhi 、 zhi chi xiao qu qie huan 、 an quan bao mi 、 wang luo yu ying yong wu guan 。HiperLAN biao zhun ding yi le xu duo zhi chi wu xian wang luo gong neng de xin ling he ce liang fang fa , bao kuo dong tai pin lv xuan ze 、 wu xian xiao qu qie huan 、 lian lu shi pei 、 duo bo shu tian xian he gong lv kong zhi deng 。HiperLan/2 biao zhun shi dui mu qian wu xian jie ru xi tong de bu chong , yu qi ta feng wo xi tong bi jiao , ta de hu wai yi dong xing sui ran shou dao xian zhi , dan shi yong mian guang , ke zai dian xing de ying yong huan jing ru ban gong shi 、 jia ting 、 zhan lan ting 、 ji chang 、 huo che zhan deng re dian di qu , xiang zhong duan yong hu ti gong gao su shu ju lv he gao xing neng 。
  er 、HiperLan/2 xi tong te dian
  zai ou zhou ,HiperLAN you 455MHz de pin pu zi yuan , mei guo wei 300 MHz, ri ben ze shi 100 MHz, bing qie zai kao lv geng duo de pin pu fen pei 。 zhe xie pin duan sui dou zai 5GHz pin duan zhong , dan bing bu tong yi ,ITU-R zheng nu li zai quan qiu fan wei nei shi xian wu xian ju yu wang tong yi pin pu fen pei 。
  tu 1 shi HiperLAN/2 de dian xing wang luo tuo pu jie gou 。 yi dong zhong duan (MT) tong guo jie ru dian (AP) jie ru gu ding wang ,MT yu AP zhi jian de kong zhong jie kou you HiperLAN/2 ding yi 。 yi ge AP suo fu gai de qu yu cheng wei yi ge xiao qu , yi ge xiao qu de fu gai fan wei zai shi nei yi ban wei 30 mi , zai shi wai yi ban wei 150 mi 。 wu xian zhong duan MT ke yi zai HiperLAN/2 wang luo zhong zi you yi dong , bing bao chi yu wang luo jian liang hao de chuan shu xing neng 。 zai mou yi ge te ding shi jian , yi dong zhong duan zhi neng yu yi ge jie ru dian tong xin 。 wu xian wang luo zi dong jin xing wu xian pin lv pei zhi 。 zhe yi fang shi bu tong yu yi wang wu xian wang luo de pin lv gui hua , xi tong pei zhi geng jia fang bian 。
无线局域网HiperLAN/2标准综述

  tu 1 HiperLAN/2 wang luo
  HiperLAN/2 shi mu qian xing neng zui gao de WLAN ji shu , qi te dian shi :
  gao su shu ju chuan shu : you yu cai yong le xian jin de OFDM tiao zhi ji shu , HiperLAN/2 ke yi ti gong fei chang gao de shu ju chuan shu su lv , qi su lv zai wu li ceng zui gao da 54Mbit/s, zai ceng san ye ke da 25Mbit/s。 zai ban gong shi zhe yang de shi jian kuo san huan jing zhong ,OFDM dui duo jing xiao ying de jie jue hen you xiao 。 tong shi , MAC cai yong le dong tai TDD mo shi , shi wu xian zi yuan de li yong geng jia you xiao 。
  mian xiang lian jie : yu qi ta wu xian ju yu wang ji shu bu tong , zai HiperLAN/2 wang luo zhong shu ju de chuan shu shi mian xiang lian jie de 。 zai chuan song shu ju zhi qian ,AP he MT zhi jian tong guo HiperLAN/2 kong zhi ceng de xin ling yu xian jian li lian jie 。 zhe zhong lian jie zai kong zhong jie kou shang shi shi fen shuang gong de , lian jie fen dian dui dian he dian dui duo dian 。 dian dui dian lian jie shi shuang xiang lian jie , dian dui duo dian shi dan xiang lian jie �� xia xing fang xiang , cong jie ru dian dao yi dong zhong duan 。 ling wai ,HiperLAN/2 huan ke yi cai yong zhuan yong guang bo xin dao , you tong yi ge AP xiang suo you yi dong zhong duan fa song guang bo xiao xi 。
  QoS:HiperLAN/2 mian xiang lian jie de te xing you li yu shi xian dui QoS de zhi chi 。 you yu gao chuan shu lv he dui QoS de zhi chi ,HiperLAN/2 ke yi tong shi chuan shu bu tong lei xing de shu ju liu , bi ru shi pin 、 hua yin he shu ju deng 。
  zi dong pin lv fen pei : zai mei yi jie ru dian fu gai qu yu zhong , jie ru dian AP neng zi dong xuan ze shi dang de wu xian xin dao jin xing chuan shu shu ju 。AP jian ting lin jin xiao qu ji huan jing zhong de qi ta wu xian zi yuan , gen ju zui xiao gan rao he zi yuan bu chong tu zhun ze xuan ze shi dang de wu xian xin dao 。
  an quan xing :HiperLAN/2 wang luo zhi chi an quan ren zheng he jia mi gong neng 。
  yi dong xing : yi dong zhong duan yu li ta zui jin de yi ge jie ru dian tong xin , que qie de shuo , yi dong zhong duan yu ju you zui hao xin zao bi de jie ru dian tong xin , yin ci , zai bu duan yi dong de qing kuang xia , yi dong yong hu ( zhong duan ) ke neng hui zhen ce dao yi ge wu xian chuan shu xing neng geng hao de jie ru dian , yu shi , yi dong zhong duan jiang zhi xing yi ci qie huan , qie huan dao yi ge xin de AP zhong , suo you yi jian li de lian jie dou zhuan yi dao xin AP shang , yi dong zhong duan reng ji xu yu wang luo bao chi tong xin 。 dang ran , zai qie huan guo cheng zhong , you ke neng hui diu shi yi xie shu ju bao , er qie , jia ru yi dong zhong duan chao chu HiperLAN/2 wang luo de fu gai fan wei xiang dang chang yi duan shi jian , jiang hui shi qu yu wang luo de lian xi , suo you lian jie jiang bei shi fang 。
  wang luo yu ying yong wu guan :HiperLAN/2 wang luo xie yi zhan ju you ling huo de ti xi jie gou , hen qing yi shi pei bing kuo zhan bu tong de gu ding wang luo 。 li ru ,HiperLAN/2 ke bei yong zuo jiao huan shi yi tai wang de wu xian bu fen ; tong yang ,HiperLAN/2 ye ke zuo wei di san dai feng wo wang luo de jie ru wang shi yong 。 mu qian zai gu ding wang shang yun xing de suo you ying yong dou ke yi zai HiperLAN/2 shang yun xing 。
  sheng dian :HiperLAN/2 de sheng dian ji zhi shi ji yu MT dui shui mian qi de chu shi yue ding 。 yi dong zhong duan ke yi zai ren he shi jian yao qiu AP jin ru di gong lv zhuang tai , bing qie qing qiu te ding de shui mian zhou qi 。 shui mian zhou qi jie shu shi , yi dong zhong duan jiang jian ce you wu AP fa lai de ji huo zhi shi , jia ru mei you jian ce dao , ze jin ru xia yi ge shui mian zhou qi , ji xu bao chi di gong lv zhuang tai 。AP zan bu fa song yong hu shu ju , deng shui mian qi jie shu hou cai kai shi fa song 。 ke yi gen ju dui fan ying shi jian he di gong hao de yao qiu , xuan ze bu tong de shui mian zhou qi 。
  san 、 xie yi ti xi jie gou
  HiperLAN/2 wu xian jie kou de xie yi shen kao mo xing ru tu 2 suo shi ,HiperLAN/2 de xie yi zhan fen cheng kong zhi ping mian he yong hu ping mian liang bu fen 。 yong hu ping mian de gong neng shi zai yi jing lian jie de lian jie shang chuan shu shu ju ; kong zhi ping mian de gong neng shi kong zhi lian jie de jian li 、 shi fang he jian kong 。HiperLAN/2 xie yi bao kuo san ge ji ben ceng : wu li ceng PHY、 shu ju lian lu ceng DLC he hui ju ceng CL。
无线局域网HiperLAN/2标准综述

  tu 2 HiperLAN/2 xie yi shen kao mo xing
  
  
   1、 wu li ceng PHY
  HiperLAN/2 de wu li ceng yi yi ding chang du de tu fa mai chong chuan (Burst) ge shi chuan shu shu ju dan yuan , mei yi ge burst fen cheng qian dao ma (PReamble) he shu ju liang ge bu fen 。
  HiperLAN/2 cai yong le OFDM(Orthogonal Frequency Division Multiplexing) tiao zhi fang an , fei fan shi yong yu xin dao cheng fa san zhuang fen bu de xi tong ,HiperLAN/2 de xin dao jian ge wei 20MHz, ke yi zhi chi fei chang gao de chuan shu su lv , shi xin dao shu mu he chuan shu gao su lv de yi zhong zhe zhong ( ru zai ou zhou cai yong le 19 ge xin dao )。 mei yi ge xin dao you fen cheng 52 ge zi xin dao 。 wei yi zhi zi xin dao zhi jian de gan rao , mei ge zi xin dao zhi jian de pin lv jian ge wei 312.5kHz, qi zhong 48 ge zi xin dao yong yu chuan song shu ju , ling wai 4 ge zi xin dao yong yu ti gong xi tong tong bu de dao pin xin hao 。 xin dao de chuan shu shi yan yi ban bu chao guo 250ns, cai yong 800ns de bao hu jian ge shi jian zu yi man zu yao qiu , zai bi jiao xiao de shi nei huan jing zhong , ke yi cai yong 400ns de geng duan de bao hu jian ge shi jian 。
  zai HiperLAN/2 de shou fa duan shi yong FFT xin hao chu li fang shi ke yi you xiao di shi xian OFDM, zhe yang , yu chuan tong de FDM xi tong xiang bi , cai yong OFDM de HiperLAN/2 xi tong ke da da jiang di ying jian she bei de fu duo du , bing qie you xiao ti gao pin pu li yong lv , zai shi jian kuo san huan jing zhong jin ke neng de yi zhi yin duo jing chuan shu er chan sheng de fu hao jian gan rao he ma pian jian gan rao 。
  yu 3G deng lei si , wei le shi ying bu tong de ye wu yao qiu he lian lu tiao jian ,HiperLAN/2 de wu li ceng ke yi ti gong duo zhong chuan shu fang shi ( cai yong bu tong de tiao zhi he bian ma fang shi ), you gao ceng xie yi gen ju ju ti yao qiu er ding 。
  2、 shu ju lian lu kong zhi ceng DLC
  shu ju lian lu ceng fu ze jian li yi dong zhong duan he jie ru dian zhi jian de luo ji lian lu 。 ta de gong neng bao kuo yong hu mian de mei ti fang wen he chuan shu ji kong zhi mian de lian jie chu li , yin ci ,DLC(Data Link Control) ceng bao kuo MAC xie yi 、 cha cuo kong zhi xie yi (EC) he wu xian lian lu kong zhi xie yi RLC san ge zi ceng 。
  MAC xie yi
  MAC xie yi yong yu fa song shu ju shi kong zhi dui wu li jie zhi de fang wen 。 wu xian jie kou ji yu TDD he dong tai de TDMA duo zhi fang an , cai yong de shi xi jie gou zai HiperLAN/2 zhong cheng zuo MAC zhen 。 gen ju suo xu yao de chuan shu zi yuan dong tai di fen pei shang xia xing lian lu de shi xi , ji ben de MAC zhen shi chang gu ding wei 2ms, bao kuo guang bo kong zhi xin dao 、 zhen kong zhi xin dao 、 jie ru kong zhi xin dao 、 shang xia xing shu ju chuan shu he sui ji jie ru 。AP he MT suo you shu ju de chuan shu dou zai zhuan yong de shi xi shang chuan shu , dan sui ji jie ru xin dao cun zai yi ge jing zheng wen ti 。 guang bo kong zhi de chi xu shi jian shi gu ding de , er qi ta bu fen de chi xu shi jian yao yi ju dang shi de chuan shu tiao jian er ding 。MAC zhen he chuan shu xin dao zu cheng shu ju lian lu ceng DLC he chuan shu ceng PHY zhi jian de jie kou 。
  
  cha cuo kong zhi xie yi EC
  cha cuo kong zhi ji zhi you zhu yu ti gao wu xian lian lu de ke kao xing , xi tong cai yong ke xuan ze chong fu ARQ。 zhe li de EC gong neng shi jian ce wei cuo , you wei cuo shi chong fa U-PDU, ye bao zheng U-PDU an shun xu fa song dao hui ju ceng , fang fa shi gei mei ge lian jie shang de U-PDU fen pei yi ge xu lie hao ,ARQ ying da de zheng que huo cuo wu xiao xi zai LCCH shang chuan song , yi ge U-PDU ke yi bei chong fa duo ci ( ci shu ke yi she ding )。
  wei bao zheng yi xie shi shi ye wu ru yu yin deng ying yong de fu wu zhi liang , xi tong da ying diu shi yi xie U-PDU。 yin wei chong fa fang shi dao zhi yi xie shu ju chen jiu shi ( ru chao guo chong fa ci shu de shang xian ),EC xie yi shang de fa song fang jiang hui fa qi “ diu shi ji zhi ”, jiang gai PDU yi ji zhe ge DUC shang qi ta dai fa de U-PDU quan bu diu shi ( fa song shi U-PDU xu lie hao yi ci jian xiao ), zhe jiu dao zhi DLC you xiao lian jie shang de PDU cun zai can que , jia ru xu yao , da ying geng shang ceng hui fu zhe xie diu shi de shu ju 。
  
  wu xian lian lu kong zhi xie yi RLC
  RLC xie yi wei xin ling shi ti ti gong chuan shu fu wu , zhu yao chu li san zhong kong zhi gong neng : yong yu jian quan 、 mi yao zhi li 、 guan lian (Association)、 qu xiao guan lian (Disassociation) yi ji jia mi zhong zi (Encryption Seed) de guan lian kong zhi gong neng (ACF); wu xian zi yuan kong zhi (RRC) gong neng zhi li qie huan 、 dong tai pin lv xuan ze 、 yi dong zhong duan de ji huo he shi fang 、 sheng dian yi ji gong lv kong zhi ;DLC yong hu lian jie kong zhi gong neng (DDC) yong yu jian li he shi fang yong hu lian jie 、 duo dian chuan song he guang bo 。
  zong zhi ,RLC yong yu zai yi ge jie ru dian he yi dong zhong duan zhi jian de kong zhi mian zhong jiao huan xin ling shu ju 。 li ru , yi dong zhong duan tong guo RLC xin ling xing cheng he jie ru dian de lian xi , wan cheng zhe ge lian xi guo cheng hou , yi dong zhong duan ke yi qing qiu yi ge zhuan ye kong zhi xin dao jian li wu xian zai ti (Radio Bearers)。 zai HiperLAN/2 zhong , wu xian zai ti cheng wei DLC lian jie 。
  3、 hui ju ceng CL
  hui ju ceng CL(Convergence Layer) ji ben jie gou ru tu 3 suo shi , ta you liang da zhu yao gong neng : shi lai zi gao ceng de fu wu qing qiu yu DLC ceng ti gong de fu wu shi pei ; jiang gao ceng gu ding huo ke bian chang du de fen zu zheng li cheng shi he yi ge ge gu ding chang du de ye wu shu ju dan yuan (SDU) zai DLC zhong shi yong , ke cai yong tian chong 、 fen ge 、 chong xin zu zhuang cheng yong yu DLC nei de gu ding chang du de SDU。 gu ding chang du DLC ye wu shu ju dan yuan de tian chong 、 fen ge he chong zu shi yi ge yao hai te zheng , ta shi de DLC he PHY ceng tuo li kai zhu gan wang du li cun zai er bu bi guan xin HiperLAN jie ru he zhong wang luo zhong , xi tong shi xian xiang dui jian dan 。CL de tong yong jie gou shi HiperLAN zu yi cheng wei kuan dai wu xian jie ru wang , ke jie ru bu tong gu ding wang luo , ru yi tai wang 、IP wang 、ATM he UMTS deng 。
无线局域网HiperLAN/2标准综述

  tu 3 hui ju ceng ji ben jie gou
  hui ju ceng you liang zhong lei xing : yi shi dan yuan shi hui ju ceng , qi gao ceng you gu ding chang du de fen zu , ru HiperLAN jie ru ATM wang luo de qing kuang ; er shi fen zu shi hui ju ceng , qi gao ceng de fen zu chang du bu gu ding , ru HiperLAN jie ru yi tai wang de qing kuang 。 fen zu shi de hui ju ceng bao kuo gong gong bu fen (Common Part) he ye wu xi jie (SSCS:Service Specific Convengence Sublayer) liang ge bu fen , zhe yang ke yi shi pei bu tong wang luo 。
  
   si 、 jie shu yu
  HiperLAN/2 ti gong le yi ge shi yong yu xiao fan wei (150 mi )、 gao su (54Mbit/s) wu xian jie ru xi tong 。 yan jiu biao ming zai da bu fen huan jing xia , ta dou ke yi ju you hen gao de xing neng 。 HiperLAN/2 suo ju you de QoS zhi chi 、 ke xuan ze chong fu ARQ、 lian lu shi pei yi ji dong tai pin lv xuan ze deng te zheng , shi de zhe yang yi ge xi tong ke yi zai chuan bo tiao jian bu duan bian hua 、 gan rao yan chong de wu xian huan jing xia de dao hen hao de ying yong 。【原文】【汉音对照
 
 
 
 
 
 
 
 
 
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zhai yao : gai kuang jie shao le HiperLan/2 biao zhun , yi ji lian lu he xi tong de xing neng 。 yao hai ci : wu xian ju yu wang (WLAN) wu xian jie ru kuan dai yi 、 gai shu wu xian he yi dong tong xin de kuai su fa zhan 、 duo mei ti ying yong de chu xian yi ji Internet jie ru de xu yao dou ci ji zhe wu xian kuan dai jie ru wang luo de jin yi bu kai fa 。 di er dai yi dong wu xian xi tong de gai jin yi ji zheng zai da li kai fa de di san dai wu xian tong xin wang de mu de jiu zai yu shi wang luo neng gou ti gong wu xian xin dao shang zui gao ke da 2Mbps de shun shi yong hu bi te lv , cong er da da ti gao fen zu shu ju he yi dong duo mei ti ying yong 。 tong shi dui yu ju yu wang cai yong yi xie xin de wu xian ji shu shen zhi ke huo de geng gao de shu ju lv 。 qi zhong xin yi dai WLAN ji shu ��HiperLAN/2 biao zhun jiu shi yi li 。 HiperLAN/2 shi mu qian zui wei wan shan de WLAN xie yi 。 ta de te dian shi : gao su chuan shu 、 mian xiang lian jie 、 zhi chi QoS、 zi dong pin lv pei zhi 、 zhi chi xiao qu qie huan 、 an quan bao mi 、 wang luo yu ying yong wu guan 。HiperLAN biao zhun ding yi le xu duo zhi chi wu xian wang luo gong neng de xin ling he ce liang fang fa , bao kuo dong tai pin lv xuan ze 、 wu xian xiao qu qie huan 、 lian lu shi pei 、 duo bo shu tian xian he gong lv kong zhi deng 。HiperLan/2 biao zhun shi dui mu qian wu xian jie ru xi tong de bu chong , yu qi ta feng wo xi tong bi jiao , ta de hu wai yi dong xing sui ran shou dao xian zhi , dan shi yong mian guang , ke zai dian xing de ying yong huan jing ru ban gong shi 、 jia ting 、 zhan lan ting 、 ji chang 、 huo che zhan deng re dian di qu , xiang zhong duan yong hu ti gong gao su shu ju lv he gao xing neng 。 er 、HiperLan/2 xi tong te dian zai ou zhou ,HiperLAN you 455MHz de pin pu zi yuan , mei guo wei 300 MHz, ri ben ze shi 100 MHz, bing qie zai kao lv geng duo de pin pu fen pei 。 zhe xie pin duan sui dou zai 5GHz pin duan zhong , dan bing bu tong yi ,ITU-R zheng nu li zai quan qiu fan wei nei shi xian wu xian ju yu wang tong yi pin pu fen pei 。 tu 1 shi HiperLAN/2 de dian xing wang luo tuo pu jie gou 。 yi dong zhong duan (MT) tong guo jie ru dian (AP) jie ru gu ding wang ,MT yu AP zhi jian de kong zhong jie kou you HiperLAN/2 ding yi 。 yi ge AP suo fu gai de qu yu cheng wei yi ge xiao qu , yi ge xiao qu de fu gai fan wei zai shi nei yi ban wei 30 mi , zai shi wai yi ban wei 150 mi 。 wu xian zhong duan MT ke yi zai HiperLAN/2 wang luo zhong zi you yi dong , bing bao chi yu wang luo jian liang hao de chuan shu xing neng 。 zai mou yi ge te ding shi jian , yi dong zhong duan zhi neng yu yi ge jie ru dian tong xin 。 wu xian wang luo zi dong jin xing wu xian pin lv pei zhi 。 zhe yi fang shi bu tong yu yi wang wu xian wang luo de pin lv gui hua , xi tong pei zhi geng jia fang bian 。 [url=http://www.wangchao.net.cn/bbs/pydetail_1747172.html][img]http://image.wangchao.net.cn/it/1323551462267.gif[/img][/url] tu 1 HiperLAN/2 wang luo HiperLAN/2 shi mu qian xing neng zui gao de WLAN ji shu , qi te dian shi : gao su shu ju chuan shu : you yu cai yong le xian jin de OFDM tiao zhi ji shu , HiperLAN/2 ke yi ti gong fei chang gao de shu ju chuan shu su lv , qi su lv zai wu li ceng zui gao da 54Mbit/s, zai ceng san ye ke da 25Mbit/s。 zai ban gong shi zhe yang de shi jian kuo san huan jing zhong ,OFDM dui duo jing xiao ying de jie jue hen you xiao 。 tong shi , MAC cai yong le dong tai TDD mo shi , shi wu xian zi yuan de li yong geng jia you xiao 。 mian xiang lian jie : yu qi ta wu xian ju yu wang ji shu bu tong , zai HiperLAN/2 wang luo zhong shu ju de chuan shu shi mian xiang lian jie de 。 zai chuan song shu ju zhi qian ,AP he MT zhi jian tong guo HiperLAN/2 kong zhi ceng de xin ling yu xian jian li lian jie 。 zhe zhong lian jie zai kong zhong jie kou shang shi shi fen shuang gong de , lian jie fen dian dui dian he dian dui duo dian 。 dian dui dian lian jie shi shuang xiang lian jie , dian dui duo dian shi dan xiang lian jie �� xia xing fang xiang , cong jie ru dian dao yi dong zhong duan 。 ling wai ,HiperLAN/2 huan ke yi cai yong zhuan yong guang bo xin dao , you tong yi ge AP xiang suo you yi dong zhong duan fa song guang bo xiao xi 。 QoS:HiperLAN/2 mian xiang lian jie de te xing you li yu shi xian dui QoS de zhi chi 。 you yu gao chuan shu lv he dui QoS de zhi chi ,HiperLAN/2 ke yi tong shi chuan shu bu tong lei xing de shu ju liu , bi ru shi pin 、 hua yin he shu ju deng 。 zi dong pin lv fen pei : zai mei yi jie ru dian fu gai qu yu zhong , jie ru dian AP neng zi dong xuan ze shi dang de wu xian xin dao jin xing chuan shu shu ju 。AP jian ting lin jin xiao qu ji huan jing zhong de qi ta wu xian zi yuan , gen ju zui xiao gan rao he zi yuan bu chong tu zhun ze xuan ze shi dang de wu xian xin dao 。 an quan xing :HiperLAN/2 wang luo zhi chi an quan ren zheng he jia mi gong neng 。 yi dong xing : yi dong zhong duan yu li ta zui jin de yi ge jie ru dian tong xin , que qie de shuo , yi dong zhong duan yu ju you zui hao xin zao bi de jie ru dian tong xin , yin ci , zai bu duan yi dong de qing kuang xia , yi dong yong hu ( zhong duan ) ke neng hui zhen ce dao yi ge wu xian chuan shu xing neng geng hao de jie ru dian , yu shi , yi dong zhong duan jiang zhi xing yi ci qie huan , qie huan dao yi ge xin de AP zhong , suo you yi jian li de lian jie dou zhuan yi dao xin AP shang , yi dong zhong duan reng ji xu yu wang luo bao chi tong xin 。 dang ran , zai qie huan guo cheng zhong , you ke neng hui diu shi yi xie shu ju bao , er qie , jia ru yi dong zhong duan chao chu HiperLAN/2 wang luo de fu gai fan wei xiang dang chang yi duan shi jian , jiang hui shi qu yu wang luo de lian xi , suo you lian jie jiang bei shi fang 。 wang luo yu ying yong wu guan :HiperLAN/2 wang luo xie yi zhan ju you ling huo de ti xi jie gou , hen qing yi shi pei bing kuo zhan bu tong de gu ding wang luo 。 li ru ,HiperLAN/2 ke bei yong zuo jiao huan shi yi tai wang de wu xian bu fen ; tong yang ,HiperLAN/2 ye ke zuo wei di san dai feng wo wang luo de jie ru wang shi yong 。 mu qian zai gu ding wang shang yun xing de suo you ying yong dou ke yi zai HiperLAN/2 shang yun xing 。 sheng dian :HiperLAN/2 de sheng dian ji zhi shi ji yu MT dui shui mian qi de chu shi yue ding 。 yi dong zhong duan ke yi zai ren he shi jian yao qiu AP jin ru di gong lv zhuang tai , bing qie qing qiu te ding de shui mian zhou qi 。 shui mian zhou qi jie shu shi , yi dong zhong duan jiang jian ce you wu AP fa lai de ji huo zhi shi , jia ru mei you jian ce dao , ze jin ru xia yi ge shui mian zhou qi , ji xu bao chi di gong lv zhuang tai 。AP zan bu fa song yong hu shu ju , deng shui mian qi jie shu hou cai kai shi fa song 。 ke yi gen ju dui fan ying shi jian he di gong hao de yao qiu , xuan ze bu tong de shui mian zhou qi 。 san 、 xie yi ti xi jie gou HiperLAN/2 wu xian jie kou de xie yi shen kao mo xing ru tu 2 suo shi ,HiperLAN/2 de xie yi zhan fen cheng kong zhi ping mian he yong hu ping mian liang bu fen 。 yong hu ping mian de gong neng shi zai yi jing lian jie de lian jie shang chuan shu shu ju ; kong zhi ping mian de gong neng shi kong zhi lian jie de jian li 、 shi fang he jian kong 。HiperLAN/2 xie yi bao kuo san ge ji ben ceng : wu li ceng PHY、 shu ju lian lu ceng DLC he hui ju ceng CL。 [url=http://www.wangchao.net.cn/bbs/pydetail_1747172.html][img]http://image.wangchao.net.cn/it/1323551462405.gif[/img][/url] tu 2 HiperLAN/2 xie yi shen kao mo xing 1、 wu li ceng PHY HiperLAN/2 de wu li ceng yi yi ding chang du de tu fa mai chong chuan (Burst) ge shi chuan shu shu ju dan yuan , mei yi ge burst fen cheng qian dao ma (PReamble) he shu ju liang ge bu fen 。 HiperLAN/2 cai yong le OFDM(Orthogonal Frequency Division Multiplexing) tiao zhi fang an , fei fan shi yong yu xin dao cheng fa san zhuang fen bu de xi tong ,HiperLAN/2 de xin dao jian ge wei 20MHz, ke yi zhi chi fei chang gao de chuan shu su lv , shi xin dao shu mu he chuan shu gao su lv de yi zhong zhe zhong ( ru zai ou zhou cai yong le 19 ge xin dao )。 mei yi ge xin dao you fen cheng 52 ge zi xin dao 。 wei yi zhi zi xin dao zhi jian de gan rao , mei ge zi xin dao zhi jian de pin lv jian ge wei 312.5kHz, qi zhong 48 ge zi xin dao yong yu chuan song shu ju , ling wai 4 ge zi xin dao yong yu ti gong xi tong tong bu de dao pin xin hao 。 xin dao de chuan shu shi yan yi ban bu chao guo 250ns, cai yong 800ns de bao hu jian ge shi jian zu yi man zu yao qiu , zai bi jiao xiao de shi nei huan jing zhong , ke yi cai yong 400ns de geng duan de bao hu jian ge shi jian 。 zai HiperLAN/2 de shou fa duan shi yong FFT xin hao chu li fang shi ke yi you xiao di shi xian OFDM, zhe yang , yu chuan tong de FDM xi tong xiang bi , cai yong OFDM de HiperLAN/2 xi tong ke da da jiang di ying jian she bei de fu duo du , bing qie you xiao ti gao pin pu li yong lv , zai shi jian kuo san huan jing zhong jin ke neng de yi zhi yin duo jing chuan shu er chan sheng de fu hao jian gan rao he ma pian jian gan rao 。 yu 3G deng lei si , wei le shi ying bu tong de ye wu yao qiu he lian lu tiao jian ,HiperLAN/2 de wu li ceng ke yi ti gong duo zhong chuan shu fang shi ( cai yong bu tong de tiao zhi he bian ma fang shi ), you gao ceng xie yi gen ju ju ti yao qiu er ding 。 2、 shu ju lian lu kong zhi ceng DLC shu ju lian lu ceng fu ze jian li yi dong zhong duan he jie ru dian zhi jian de luo ji lian lu 。 ta de gong neng bao kuo yong hu mian de mei ti fang wen he chuan shu ji kong zhi mian de lian jie chu li , yin ci ,DLC(Data Link Control) ceng bao kuo MAC xie yi 、 cha cuo kong zhi xie yi (EC) he wu xian lian lu kong zhi xie yi RLC san ge zi ceng 。 MAC xie yi MAC xie yi yong yu fa song shu ju shi kong zhi dui wu li jie zhi de fang wen 。 wu xian jie kou ji yu TDD he dong tai de TDMA duo zhi fang an , cai yong de shi xi jie gou zai HiperLAN/2 zhong cheng zuo MAC zhen 。 gen ju suo xu yao de chuan shu zi yuan dong tai di fen pei shang xia xing lian lu de shi xi , ji ben de MAC zhen shi chang gu ding wei 2ms, bao kuo guang bo kong zhi xin dao 、 zhen kong zhi xin dao 、 jie ru kong zhi xin dao 、 shang xia xing shu ju chuan shu he sui ji jie ru 。AP he MT suo you shu ju de chuan shu dou zai zhuan yong de shi xi shang chuan shu , dan sui ji jie ru xin dao cun zai yi ge jing zheng wen ti 。 guang bo kong zhi de chi xu shi jian shi gu ding de , er qi ta bu fen de chi xu shi jian yao yi ju dang shi de chuan shu tiao jian er ding 。MAC zhen he chuan shu xin dao zu cheng shu ju lian lu ceng DLC he chuan shu ceng PHY zhi jian de jie kou 。 cha cuo kong zhi xie yi EC cha cuo kong zhi ji zhi you zhu yu ti gao wu xian lian lu de ke kao xing , xi tong cai yong ke xuan ze chong fu ARQ。 zhe li de EC gong neng shi jian ce wei cuo , you wei cuo shi chong fa U-PDU, ye bao zheng U-PDU an shun xu fa song dao hui ju ceng , fang fa shi gei mei ge lian jie shang de U-PDU fen pei yi ge xu lie hao ,ARQ ying da de zheng que huo cuo wu xiao xi zai LCCH shang chuan song , yi ge U-PDU ke yi bei chong fa duo ci ( ci shu ke yi she ding )。 wei bao zheng yi xie shi shi ye wu ru yu yin deng ying yong de fu wu zhi liang , xi tong da ying diu shi yi xie U-PDU。 yin wei chong fa fang shi dao zhi yi xie shu ju chen jiu shi ( ru chao guo chong fa ci shu de shang xian ),EC xie yi shang de fa song fang jiang hui fa qi “ diu shi ji zhi ”, jiang gai PDU yi ji zhe ge DUC shang qi ta dai fa de U-PDU quan bu diu shi ( fa song shi U-PDU xu lie hao yi ci jian xiao ), zhe jiu dao zhi DLC you xiao lian jie shang de PDU cun zai can que , jia ru xu yao , da ying geng shang ceng hui fu zhe xie diu shi de shu ju 。 wu xian lian lu kong zhi xie yi RLC RLC xie yi wei xin ling shi ti ti gong chuan shu fu wu , zhu yao chu li san zhong kong zhi gong neng : yong yu jian quan 、 mi yao zhi li 、 guan lian (Association)、 qu xiao guan lian (Disassociation) yi ji jia mi zhong zi (Encryption Seed) de guan lian kong zhi gong neng (ACF); wu xian zi yuan kong zhi (RRC) gong neng zhi li qie huan 、 dong tai pin lv xuan ze 、 yi dong zhong duan de ji huo he shi fang 、 sheng dian yi ji gong lv kong zhi ;DLC yong hu lian jie kong zhi gong neng (DDC) yong yu jian li he shi fang yong hu lian jie 、 duo dian chuan song he guang bo 。 zong zhi ,RLC yong yu zai yi ge jie ru dian he yi dong zhong duan zhi jian de kong zhi mian zhong jiao huan xin ling shu ju 。 li ru , yi dong zhong duan tong guo RLC xin ling xing cheng he jie ru dian de lian xi , wan cheng zhe ge lian xi guo cheng hou , yi dong zhong duan ke yi qing qiu yi ge zhuan ye kong zhi xin dao jian li wu xian zai ti (Radio Bearers)。 zai HiperLAN/2 zhong , wu xian zai ti cheng wei DLC lian jie 。 3、 hui ju ceng CL hui ju ceng CL(Convergence Layer) ji ben jie gou ru tu 3 suo shi , ta you liang da zhu yao gong neng : shi lai zi gao ceng de fu wu qing qiu yu DLC ceng ti gong de fu wu shi pei ; jiang gao ceng gu ding huo ke bian chang du de fen zu zheng li cheng shi he yi ge ge gu ding chang du de ye wu shu ju dan yuan (SDU) zai DLC zhong shi yong , ke cai yong tian chong 、 fen ge 、 chong xin zu zhuang cheng yong yu DLC nei de gu ding chang du de SDU。 gu ding chang du DLC ye wu shu ju dan yuan de tian chong 、 fen ge he chong zu shi yi ge yao hai te zheng , ta shi de DLC he PHY ceng tuo li kai zhu gan wang du li cun zai er bu bi guan xin HiperLAN jie ru he zhong wang luo zhong , xi tong shi xian xiang dui jian dan 。CL de tong yong jie gou shi HiperLAN zu yi cheng wei kuan dai wu xian jie ru wang , ke jie ru bu tong gu ding wang luo , ru yi tai wang 、IP wang 、ATM he UMTS deng 。 [url=http://www.wangchao.net.cn/bbs/pydetail_1747172.html][img]http://image.wangchao.net.cn/it/1323551462592.gif[/img][/url] tu 3 hui ju ceng ji ben jie gou hui ju ceng you liang zhong lei xing : yi shi dan yuan shi hui ju ceng , qi gao ceng you gu ding chang du de fen zu , ru HiperLAN jie ru ATM wang luo de qing kuang ; er shi fen zu shi hui ju ceng , qi gao ceng de fen zu chang du bu gu ding , ru HiperLAN jie ru yi tai wang de qing kuang 。 fen zu shi de hui ju ceng bao kuo gong gong bu fen (Common Part) he ye wu xi jie (SSCS:Service Specific Convengence Sublayer) liang ge bu fen , zhe yang ke yi shi pei bu tong wang luo 。 si 、 jie shu yu HiperLAN/2 ti gong le yi ge shi yong yu xiao fan wei (150 mi )、 gao su (54Mbit/s) wu xian jie ru xi tong 。 yan jiu biao ming zai da bu fen huan jing xia , ta dou ke yi ju you hen gao de xing neng 。 HiperLAN/2 suo ju you de QoS zhi chi 、 ke xuan ze chong fu ARQ、 lian lu shi pei yi ji dong tai pin lv xuan ze deng te zheng , shi de zhe yang yi ge xi tong ke yi zai chuan bo tiao jian bu duan bian hua 、 gan rao yan chong de wu xian huan jing xia de dao hen hao de ying yong 。
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