WLAN技术及其测试

WLAN技术及其测试什么是

WLAN?(WirelessLocalAreanetwork)WLAN:无线局域网，即没有线缆的局域网，实际上就是用无线电波代替以太网中的cable，进行信号的传输和宽带的接入WLANapplicationIEEE802.11规范

Whatisit?a4.8to6GHz,54MbpsWLANstandardb2.4GHz,11MbpsWLANstandardcBridgesconnectionsbetweenaccesspointsdHarmonisationof802.11afreqplaneQoSspecforsteamedvideoandVoIPfRoamingbetweenaccesspointsfromdifferingnetworksg2.4GHz,54MbpsWLANstandardhPowercontrolforEuropeanmarketiAdditionalsecurityfeaturesjJapaneseversionof802.11a(freqplan,andadditionalNationalregulatoryrequirements)kRadioandnetworkinformationforlocationbasedapplicationslNotusedmMaintenanceofstandardnHigherdataratestandard–notyetratified（更高速率的规范－还未发布）WLAN规范发布1997IEEE802.11–1997年无线局域网标准发布只支持1Mbit/s和2Mbit/s1999IEEE802.11b-1999年扩展了物理层规范增加了5.5Mbit/s和11Mbit/sIEEE802.11a–1999年增加5GHz的规范增加了6,9,12,18,24,36,48,54Mbit/s速率2003IEEE802.11g–2003年发布54Mbit/sin2.4GHzbandIEEE802.11a/b/g标准802.11b802.11g802.11a频率2.4GHz2.4GHz4.9–5.85GHz速率1to11Mbpsto54Mbpsto54Mbps净速率4Mbps30Mbps30Mbps调制方式

DSSS(直接序列扩频)1MbpsBarkerDBPSK

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

OFDM

（正交频分复用）

6/9MbpsBPSK12/18MbpsQPSK24/36Mbps16QAM48/54Mbps64QAM信道数14实际信道数受限于各国的相应规定13实际信道数受限于各国的相应规定30实际信道数受限于各国的相应规定颁布时间199920031999覆盖范围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速率等级AnalogmodulationDigitalmodulation01010

IEEE802.11b射频测试IEEE编号测试项目要求测试用途MT8860C

是否支持？18.4.7.1Transmitpowerlevels

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

（频谱模板）DefinedlimitmaskProductionYes18.4.7.4Transmitcenterfrequencytolerance

（中心频率容限）±25ppmProductionYes18.4.7.5Chipclockfrequencytolerance

（码片时钟频率容限）±25ppmR&DYes18.4.7.6Transmitpower-onandpower-downramp

（上升时间/下降时间）<2µsR&DYes18.4.7.7RFcarriersuppression

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

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

（接收机灵敏度）FER<8%for–76dBminput,11Mbit/sProductionYes18.4.8.2Receivermaximuminputlevel

（接收机最大输入电平）FER<8%for–10dBminput,11Mbit/sR&DYes18.4.8.3Receiveradjacentchannelrejection

（接收机临道功率抑制）ACR>35dBwithFER<8%,25MHzseparationR&DYes

(withsecondsource)18.4.8.4ClearChannelAssessment(CCA)

（信道估计）

AbilitytofindclearchannelR&DYes

(witho’scope)IEEE802.11a/g射频测试IEEE编号测试项目要求测试用途MT8860C

是否支持?19.4.7.1Transmitterpowerlevels

（发射功率）Followsnationalregulatoryrequirementsfor

2.4GHzISMbandProductionYes19.5.4(17.3.9.2)Transmitterspectrummask

（频谱模板）DefinedlimitmaskProductionYes17.3.9.3Transmissionspurious

（杂散发射）SetbyNationalregulationsR&DNo19.4.7.2Transmitcenterfrequencytolerance

（中心频率容限）±25ppmProductionYes19.4.7.3Symbolclockfrequencytolerance

（符号时钟频率容限）±25ppmR&DYes17.3.9.6.1Transmittercenterfrequencyleakage

（发射机中心频率泄漏）-15dBrelativetooveralloutputpowerR&DYes17.3.9.6.2Transmitterspectralflatness

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

（星座误差）-25dBRMSEVMfor54Mbit/sProductionYes19.5.1(17.3.10.1)Receiverminimuminputsensitivity

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

（临道功率抑制）PER<10%,3dBinterfererR&DYes

(withsecondsource)17.3.10.3Non-adjacentchannelrejection

（非临道功率抑制）PER<10%,3dBinterfererR&DYes

(withsecondsource)19.5.3Receivermaximuminputlevel

（接收机最大输入电平）PER<10%for–30dBminputR&DYes19.4.6

ClearChannelAssessment(CCA)

（信道估计）AbilitytofindclearchannelR&DYes

(witho’scope)802.11b测量18.4.7.1–发射功率调制方式DSSS(DBPSK/DQPSK/CCK)Gates之间的平均功率典型的发射功率在＋14dBm左右18.4.7.2–功率控制被测件功率>20dBm时才需要测试允许4各功率等级Gate内的平均功率18.4.7.7–载波抑制要求抑制达15dB以上被测件发出的调制信号必须内有加扰，且为10101010payload18.4.8.1–接收灵敏度FER<8%for–80dBminputat2Mbit/sFER<8%for–76dBminputat11Mbit/sMT8860B计算从DUT反馈回来的Acknowledge数据包来计算FER18.4.8.2–接收机最大输入电平FER<8%for–10dBminputat11Mbit/s18.4.8.1–邻道抑制25MHzchannelseparationOn-channelsignalat–70dBm35dBleveloffsetbetweenwantedandadjacentsignalsFER<8%for11Mbit/srateWantedsignalInterfererFcFc+25MHz802.11a/g