射頻鏈路指標預算…目錄中頻盤鏈路構成OIP3與NF計算公式發射通道鏈路預算反饋通道鏈路預算接收通道鏈路預算基本公式ACPR分析本振泄露分析DPD通道分析接收靈敏度分析阻塞與反混疊濾波器分析互調分析半中頻雜散分析LC濾波器設計濾波器帶寬要求中頻盤鏈路構成OIP3與NF計算公式以兩階系統為例：發射通道鏈路預算G=10dB，NF=18.9，OIP3=31.5，Pout=-3.5PinTX-13.5DeviceGainNFIP3SGainSNFSIP3PoutLPF-11100-11100-14.5TRF37031112301223-13.5PI-55100-512.555428818-18.5RFFILTER-44100-913.5778651914-22.5PI-44100-1315.415986510-26.5BG18C15.54.5402.518.5176614225.34858-11HMC472-3335-0.518.5517219722.11891-14PI-33100-3.518.6188937319.11891-17BG18C15.54.5401218.855325133.51415-1.5PI-221001018.8574106631.51415-3.5反饋通道鏈路預算G=-15.5dB，NF=33.5，OIP3=33.8，Pout=0PinCP15.5DeviceGainNFIP3SGainSNFSIP3PoutHMC472-171735-171735-1.5HMC349-1149-181833.86479-2.5HMC485-9940-272724.73366-11.5LPF-11100-282823.73366-12.5PI-11100-292922.73366-13.5BIF3164.540-1333.536.310542.5LPF00100-1333.536.310542.5PI-11100-1433.5100105635.310541.5ETC412-1.51.5100-15.533.530020533.810530接收通道鏈路預算G=54.5dB，NF=3.21，OIP3=34.3PinRX-125DeviceGainNFIP3SGainSNFSIP3PoutLNA3033030330-95PI-22100283.00127290928-97HMC485-9940193.02515252418.96564-106LPF-11100183.03220093517.96564-107PI-22100163.05218304315.96564-109BIF3205.240363.1752821634.51999-89HMC4720035363.1752821631.74307-89SAWFILTER-101010026374307-99PI-3310023374307-102BIF3205.240433.20931746636.31592-82pxv1220s-33100403.20942092933.31592-85BIF3205.240603.20990030539.80218-65LPF-11100593.20990084238.80218-66PI-33100563.20990344135.80218-69ETC412-1.51.510054.53.2099055934.30218-70.5基本公式系統ACPR=RFPower–熱噪聲–NF-信號底噪–最大非線性產物接收靈敏度=熱噪聲+NF+SNR–處理增益OIP3=RFPower+IMD3/2，IMD3=RFPower–最大非線性產物最大非線性產物=RFPower–2*(OIP3-RFPower)OIP3=IIP3+G，IIP3=RFPower(Input)+IMD3/2(Input)接收系統串聯IIP2=2*RFPower+Pr=RFPower+IMR2IMR2=RFPower-PrACPR分析1.DAC時鐘相噪對DAC輸出信號底噪的貢獻：-145-20lg(737.28M/140M)=-159.43dBm/Hz2.DAC輸出信號的總底噪：-159.43+(-158)=-155.58dBm/Hz3.3.84M帶寬的擴頻增益：10lg3.84M=65.84dB4.DAC在發射通道輸出口的總噪聲：-155.58+65.84+10=-79.74dBm/3.84MHz5.發射通道輸出口的總熱噪聲：-174+65.84+10+18.86=-79.3dBm/3.84MHz6.發射通道輸出口的信號底噪：-79.3+(-79.74)=-76.5dBm/3.84MHz7.發射通道輸出口的最大非線性產物：-3.5–2*(31.5+3.5)=-73.5dBm8.發射信號的ACPR：[-76.5+(-73.5)]–(-3.5)=-68.2ACPRanalysisLOGorFMAGNITUDEKTB-1743.98107E-18SAMPLECLK(M)737.28

BW3840000

IF(M)140

CLKNOISE-145

DACNOISE-1581.58489E-16CLKTODACNOISE-159.431.14023E-16DACOUTPUTNOISE-155.5832.76493E-16BWGAIN65.84331

DACNOISEFLOOR-89.73981.06173E-09CHANNELNF18.86

CHANNELGAIN10

CHANNELOIP331.5

SIGNALPOWER-3.5

SIGNALNoise-79.73981.06173E-08KTBNoise-79.29671.17579E-08SIGNALNF-76.50232.23753E-08CHANNELOIP3TOACPR-70

MAXP3rd-73.54.46684E-08TotalCHANNELNoise-71.73646.70436E-08CHANNELMAXACPR-68.2364

本振泄露分析1.功放口的本振泄露：-35+10+50-35=-10dBm2.共站時腔體濾波器所需抑制度：-10–(-86)=76dBLOleakageLOGorFIQleakage-35TXchannelgain10PAgain50RFfilter35PAleakage-10coexistrequirement-86Cavityfilter76DPD通道分析1.進入ADC的熱噪聲：-174+65.84+33.5-15.5=-90.16dBm/3.84MHz2.進入ADC的最大非線性產物：0–2*(33.8+0)=-67.6dBm3.ADC的底噪：4–66–10lg(92.16M/3.84M)=-75.8dBm/3.84MHz4.反饋信號進入ADC后所能達到的最大ACPR：[-90.16+(-67.6)+(-75.8)]–0=-66.97DPDanalysisLOGorFMAGNITUDECHANNELNF33.5

CHANNELGAIN-15.5

CHANNELOIP333.8

SIGNALPOWER0

KTBNF-90.1567

NFTOACPR-90.15679.64564E-10OIP3TOACPR-67.61.7378E-07ADCFSPower4

ADCSNR66

ADCNF-75.80212.62899E-08CHANNELMAXACPR-66.96732.01035E-07接收靈敏度分析1.WCDMA靈敏度測試使用的是單載波3.84M帶寬。2.處理增益：10lg(3.84M/12.2k)=25dB3.4.5M的熱噪聲：-174+10lg3.84M=-108.16dBm/3.84MHz4.接收靈敏度：-108.16–25+3.2+6=-123.96dBm/3.84M(協議要求低于-121dBm)RSSIanalysisLOGorFMAGNITUDEKTB-174

BW3840000

BWGAIN65.84331

NF3.2

KTB3.84MBW-108.157

KTBNF-104.957

ProcessGain25

SNR6

ReceiveSensitivity-123.957

阻塞與反混疊濾波器分析1.當有大阻塞信號進入時，為了使ADC不溢出，混頻器與小功率放大器有更好的線性表現，上行DCA增益是需要衰減的。衰減后整個上行的噪聲系數為5.5。2.熱噪聲：-174+10lg3.84M+5.5=-102.66dBm/3.84M3.除去熱噪后可接受的總噪聲：-96–(-102.66)=-97.06dBm4.帶內反混疊濾波器所需要的抑制度：-35–(-97.06)=62.06dB5.考慮到上行通道的平坦度，以及阻塞大信號進入上行通道后所引起的非線性效應，需要再保留3dB。帶內反混疊濾波器所需要的抑制度：62.06+3=65dB6.帶外阻塞信號為-15dBm，所以對于帶外阻塞信號反混疊濾波器所需要的抑制度：-15-（-97.06）+3=85.06dBBlockanalysisLOGorFMAGNITUDEBLOCKSIGNAL-353GPP=-40dBWantedSINGAL-115

SNR6

ProcessGain25

AcceptableMAXnoise-962.51189E-10ChannelNF5.5

KTB-174

3.84MBWKTBwithNF-102.6575.42414E-11TotalNoise-97.05651.96947E-10FilterRestriction62.0565

互調分析1.在天線口除去熱噪聲后最大可接受的噪聲：-97.06dBm2.假設互調產物占50%：-97.06–3=-100.06dBm3.輸入IIP3：-48+[-48–(-100.6)]/2=-21.97dBm4.輸出OIP3：-21.97+50=28.03dBm互調信號相對于靈敏度信號依然是大信號，所以上行通道也需要做適當的衰減，這樣可以降低上行通道OIP3的要求，節約器件成本。IP3analysisLOGorFMAGNITUDEWantedSINGAL-115

SNR6

ProcessGain25

AcceptableMAXnoise-962.51189E-10KTBIN3.84MBW-102.6575.42414E-11MAXNoiseexceptKTB-97.05651.96947E-10IMproduct-100.057Assume50%CHANNELGAIN50

3GPP-48dBm-48

IIP3-21.9717

OIP328.02825

半中頻雜散分析1.半中頻雜散：頻率為IF/2+Flo，經過混頻器下變頻以后會進入中頻不會被混頻器以后