SensitivityReceiverQuality(CBT)??根据RF测试规范的测试条件:??DUT处于loopback测试模式,PRBS比特类型,DH1/DH5,非跳频??DUT以最大功率返回信号??Tester发送的测试信号:??DUT输入功率为-70dBm??采用不理想的发射机(DirtyTransmitter)??分别在最低、中间、最高工作频点测量??BER的计算至少需要DUT返回1600000比特??测试仪不能完全地接收的所有数据包不会作为测量使用(误包—作为PER统计)??期望输出??BER<0.1%??规范没有约定PER容限值Jackychen46R&SCBTandR&SCBT32BluetoothPrinciple06/2007DisplayofresultsDisplayoftheBERandPERresultsBERBERresultresultPERPERresultresult已接收数据包已接收数据包Jackychen47R&SCBTandR&SCBT32BluetoothPrinciple06/2007ReceiverQualitymeasurementsPER定义??CBT忽略从DUT返回给CBT遭损坏的数据包CBTreceivesPacketwithcorrectCRCandcorrectpacketheader(HEC)Packetwithpayloadfailure(CRC)Packetwithfailureinthepacketheader(HEC)PacketwithwrongpacketlengthNullpacketNopacketPacketincreasesthePERNOYESYESYESYESYESPacketconsideredforBERYESNONONONONOJackychen48R&SCBTandR&SCBT32BluetoothPrinciple06/2007DirtyTransmitterChangeChangeofofparameterparametersetseteveryevery2020msmsPacketTypeDH1+/-25kHz1.6kHzDH3+/-40kHz500HzDH5+/-40kHz300HzAdditionalAdditionalsuperpositionsuperpositionofofaafrequencyfrequencydrift,drift,alternatealternatepacketspacketsswitchswitchstartstartphasephasebetweenbetween00andand180180degreesdegreesDeviationModulationfrequencyJackychen49R&SCBTandR&SCBT32BluetoothPrinciple06/2007DirtyTransmitter??CBT??DirtyTX?SpecTable‘??DirtyTransmitteraccordingRFTestSpecisactivated??driftisswitchedonJackychen50R&SCBTandR&SCBT32BluetoothPrinciple06/2007
蓝牙基础原理与测试 - 图文
