WLAN技術及其測試

WLAN技術及其測試什么是

WLAN?(WirelessLocalAreanetwork)WLAN:無線局域網(wǎng)，即沒有線纜的局域網(wǎng)，實際上就是用無線電波代替以太網(wǎng)中的cable，進行信號的傳輸和寬帶的接入WLANapplicationIEEE802.11規(guī)范

Whatisit?a4.8to6GHz,54MbpsWLANstandardb2.4GHz,11MbpsWLANstandardcBridgesconnectionsbetweenaccesspointsdHarmonisationof802.11afreqplaneQoSspecforsteamedvideoandVoIPfRoamingbetweenaccesspointsfromdifferingnetworksg2.4GHz,54MbpsWLANstandardhPowercontrolforEuropeanmarketiAdditionalsecurityfeaturesjJapaneseversionof802.11a(freqplan,andadditionalNationalregulatoryrequirements)kRadioandnetworkinformationforlocationbasedapplicationslNotusedmMaintenanceofstandardnHigherdataratestandard–notyetratified（更高速率的規(guī)范－還未發(fā)布）WLAN規(guī)范發(fā)布1997IEEE802.11–1997年無線局域網(wǎng)標準發(fā)布只支持1Mbit/s和2Mbit/s1999IEEE802.11b-1999年擴展了物理層規(guī)范增加了5.5Mbit/s和11Mbit/sIEEE802.11a–1999年增加5GHz的規(guī)范增加了6,9,12,18,24,36,48,54Mbit/s速率2003IEEE802.11g–2003年發(fā)布54Mbit/sin2.4GHzbandIEEE802.11a/b/g標準802.11b802.11g802.11a頻率2.4GHz2.4GHz4.9–5.85GHz速率1to11Mbpsto54Mbpsto54Mbps凈速率4Mbps30Mbps30Mbps調制方式

DSSS(直接序列擴頻)1MbpsBarkerDBPSK

2MbpsBarkerDQPSK5.5&11MbpsCCKDQPSK1/2/5.5/11Mbps調制方式同802.11b(1)

OFDM

（正交頻分復用）

6/9MbpsBPSK12/18MbpsQPSK24/36Mbps16QAM48/54Mbps64QAM信道數(shù)14實際信道數(shù)受限于各國的相應規(guī)定13實際信道數(shù)受限于各國的相應規(guī)定30實際信道數(shù)受限于各國的相應規(guī)定頒布時間199920031999覆蓋范圍30to300m30to300m20to50m（1）802.11g兼容802.11b的1/2/5.5/11Mbps,并增加了6/9/12/18/24/36/48/54Mbps速率等級AnalogmodulationDigitalmodulation01010

IEEE802.11b射頻測試IEEE編號測試項目要求測試用途MT8860C

是否支持？18.4.7.1Transmitpowerlevels

（發(fā)射功率）Followsnationalregulatoryrequirementsfor2.4GHzISMbandProductionYes18.4.7.2Transmitpowerlevelcontrol（功率控制）Requiredforradios>100mWProductionYes18.4.7.3.Transmitspectrummask

（頻譜模板）DefinedlimitmaskProductionYes18.4.7.4Transmitcenterfrequencytolerance

（中心頻率容限）±25ppmProductionYes18.4.7.5Chipclockfrequencytolerance

（碼片時鐘頻率容限）±25ppmR&DYes18.4.7.6Transmitpower-onandpower-downramp

（上升時間/下降時間）<2μsR&DYes18.4.7.7RFcarriersuppression

（載波抑制）15dBforunscrambled10payloadR&DYes18.4.7.8Transmitmodulationaccuracy

（調制精度）<0.35EVMpeakforhighestdatarateR&D/ProductionYes18.4.8.1Receiverminimuminputsensitivity

（接收機靈敏度）FER<8%for–76dBminput,11Mbit/sProductionYes18.4.8.2Receivermaximuminputlevel

（接收機最大輸入電平）FER<8%for–10dBminput,11Mbit/sR&DYes18.4.8.3Receiveradjacentchannelrejection

（接收機臨道功率抑制）ACR>35dBwithFER<8%,25MHzseparationR&DYes

(withsecondsource)18.4.8.4ClearChannelAssessment(CCA)

（信道估計）

AbilitytofindclearchannelR&DYes

(witho’scope)IEEE802.11a/g射頻測試IEEE編號測試項目要求測試用途MT8860C

是否支持?19.4.7.1Transmitterpowerlevels

（發(fā)射功率）Followsnationalregulatoryrequirementsfor

2.4GHzISMbandProductionYes19.5.4(17.3.9.2)Transmitterspectrummask

（頻譜模板）DefinedlimitmaskProductionYes17.3.9.3Transmissionspurious

（雜散發(fā)射）SetbyNationalregulationsR&DNo19.4.7.2Transmitcenterfrequencytolerance

（中心頻率容限）±25ppmProductionYes19.4.7.3Symbolclockfrequencytolerance

（符號時鐘頻率容限）±25ppmR&DYes17.3.9.6.1Transmittercenterfrequencyleakage

（發(fā)射機中心頻率泄漏）-15dBrelativetooveralloutputpowerR&DYes17.3.9.6.2Transmitterspectralflatness

（頻譜平坦度）±2dBmaximumdeviationforsubcarrier1to16,(+2to–4dBforsubcarrier17to26)R&DYes17.3.9.6.3Transmitterconstellationerror

（星座誤差）-25dBRMSEVMfor54Mbit/sProductionYes19.5.1(17.3.10.1)Receiverminimuminputsensitivity

（接收靈敏度）PER<10%for–65dBminput,54Mbit/sProductionYes19.5.2Adjacentchannelrejection

（臨道功率抑制）PER<10%,3dBinterfererR&DYes

(withsecondsource)17.3.10.3Non-adjacentchannelrejection

（非臨道功率抑制）PER<10%,3dBinterfererR&DYes

(withsecondsource)19.5.3Receivermaximuminputlevel

（接收機最大輸入電平）PER<10%for–30dBminputR&DYes19.4.6

ClearChannelAssessment(CCA)

（信道估計）AbilitytofindclearchannelR&DYes

(witho’scope)802.11b測量18.4.7.1–發(fā)射功率調制方式DSSS(DBPSK/DQPSK/CCK)Gates之間的平均功率典型的發(fā)射功率在＋14dBm左右18.4.7.2–功率控制被測件功率>20dBm時才需要測試允許4各功率等級Gate內的平均功率18.4.7.7–載波抑制要求抑制達15dB以上被測件發(fā)出的調制信號必須內有加擾，且為10101010payload18.4.8.1–接收靈敏度FER<8%for–80dBminputat2Mbit/sFER<8%for–76dBminputat11Mbit/sMT8860B計算從DUT反饋回來的Acknowledge數(shù)據(jù)包來計算FER18.4.8.2–接收機最大輸入電平FER<8%for–10dBminputat11Mbit/s18.4.8.1–鄰道抑制25MHzchannelseparationOn-channelsignalat–70dBm35dBleveloffsetbetweenwantedandadjacentsignalsFER<8%for11Mbit/srateWantedsignalInterfererFcFc+25MHz802.11a/g