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按一下以編輯母片標題樣式,按一下以編輯母片,第二層,第三層,第四層,第五層,精品课件,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,二级,三级,四级,五级,精品课件,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,二级,三级,四级,五级,精品课件,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,二级,三级,四级,五级,精品课件,*,RF Calibration Introduction,1,精品课件,RF Calibration Introduction1精品,Agenda,What is RF calibration.,Why calibration.,NV items of RF calibration.,Rx Calibration.,Tx Calibration.,2,精品课件,AgendaWhat is RF calibration.2,What is RF calibration,RF calibration is the process of measuring data to be used in the,system for the purpose of compensation of non-linear,characteristics and frequency variations,and to provide absolute,power reference and temperature compensation to ensure,performance of the Tx and Rx paths of a subscriber unit.,Output from the calibration process is stored in non-volatile(NV),memory items in AMSS.,AMSS uses calibration values during normal operation to ensure,system performance is met.,3,精品课件,What is RF calibration RF cal,Setup:,What is RF calibration,4,精品课件,Setup:What is RF calibration4精,Why calibration,Subscriber units have differing RF characteristics,Differences in design,Part-to-part variations of components of the same design,5,精品课件,Why calibrationSubscriber unit,Individual phones also change their own RF characteristics:,over frequency channel,over temperature,Why calibration,6,精品课件,Individual phones also change,Why calibration,The subscriber unit must estimate the Rx power properly to,maximize signal-to-noise ratios and to provide a basis for Tx,power output.,The subscriber unit must transmit at correct Tx power level over,its large dynamic range.,The Mobile Station Modem(MSM)device and system software,combination must know the RF and analog characteristics of the,particular unit.,Failure to compensate for differing RF/analog characteristics may,cause the unit to fail minimum performance specifications,7,精品课件,Why calibration The subscriber,The compensation values are classified:,Static RF NV items:,Measured once per design.,Calculated RF NV items:,RF NV items that are calculated based on other parameters of the design configurations.,Measured RF NV items:,Is determined by the RF calibration process.,NV items of RF calibration,8,精品课件,The compensation values are cl,Rx calibration,Philosophy of Rx AGC(Automatic Gain control)loop.,DVGA(Digital VGA)offset calibration.,LNA(Low Noise Amplifier)offset calibration.,9,精品课件,Rx calibration9精品课件,Rx calibration(Rx AGC loop),Each Rx chain has its own receiver.,Receiver calibration primarily consists of measuring the,DVGA offset,(also called VGA gain offset)and multiple,LNA offsets,all at each chosen frequency index.,Software loads the frequency-compensated DVGA and LNA offset values into the hardware registers shown above.,10,精品课件,Rx calibration(Rx AGC loop)Ea,Philosophy of Rx DVGA offset calibration:,Rx calibration(DVGA offset),11,精品课件,Philosophy of Rx DVGA offset c,Rx calibration(LNA offset),Philosophy of Rx LNA offset calibration:,12,精品课件,Rx calibration(LNA offset)Phi,Rx calibration(LNA offset),13,精品课件,Rx calibration(LNA offset)13精,Tx calibration,Philosophy of Tx AGC(Automatic Gain control)loop.,Tx Linearizer,Tx Compensation,HDET(High power detector),14,精品课件,Tx calibration14精品课件,Tx calibration(AGC Loop),The transmitter AGC must adjust the,Tx power level based on the RSSI,access probe parameters,closed-loop power-control bits(PCBs),and channel-configuration attributes.,15,精品课件,Tx calibration(AGC Loop)The t,Tx calibration(AGC Loop),16,精品课件,Tx calibration(AGC Loop)16精品课,Tx calibration(Tx AGC Characteristic),17,精品课件,Tx calibration(Tx AGC Charact,Tx calibration(Tx Linearizer),18,精品课件,Tx calibration(Tx Linearizer),Tx calibration(TX_GAIN_CTRL.),19,精品课件,Tx calibration(TX_GAIN_CTRL.),Tx calibration(,HDET Feedback loop op.,),20,精品课件,Tx calibration(HDET Feedback,Tx compensation(1/3):,NV_BCy_TX_COMP0_I NV_BCy_TX_COMP3_I,NV_BCy_TX_COMP0_I=CDMA_TX_COMP_VS_FREQ15:0+,CDMA_TX_LIN_VS_TEMP7:0+,CDMA_TX_SLP_VS_TEMP7:0,Tx calibration(Tx Comp.),21,精品课件,Tx compensation(1/3):NV_BCy_,CDMA_TX_LIN_VS_TEMP7:0:,-Used to shift the effective Tx-linearizer curve by a constant for temperature-based gain changes.,For example:,Given temperature index,the element,in this table is 0 x05,each of the 36 offsets in the adjusted master curve table will be increased by five,when the temperature corresponds to that given index.,CDMA_TX_SLP_VS_TEMP7:0,-Used to shift the effective Tx-linearizer curve by a graduated amount for temperature-based gain changes.,Ps.typically all zeros unless extra precision is desired.,Tx calibration(Tx Comp.),22,精品课件,CDMA_TX_LIN_VS_TEMP7:0:Tx c,High-power detector(HDET)(1/5):,1.Output at the power level defined by TX_GAIN_CTL.,2.The HDET circuit measures the output power.,3.The HDET value is sampled.,4.Table that maps the HDET value to Tx power level.The HDETs estimated power level is compared to TX_GAIN_CTL to determine an error value.TX_GAIN_LIMIT is adjusted by that error value.,Note:Only the maximum power,limit,is affected by the HDET circuit.,Tx calibration(Tx HDET),23,精品课件,High-po
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