Introduction to PowerControl of RG000003CDMA 1XISSUE 2.1
One of the aims of the CDMA1X system isto maximize the number of its users. If eachmobile station (MS) adjusts its transmi...
GoalsGoalsAfter learning this course, you will learn thefollowing : The importance of the power control of theCDMA system...
Chapter 1 Goals and Principles of Power ControlChapter 1 Goals and Principles of Power ControlChapter 2 Categories and Ari...
Goals and Principles of Power ControlGoals and Principles of Power ControlCDMA Concept: cocktail loungeCDMA Concept: cockt...
Goals and Principles of Power ControlGoals and Principles of Power ControlGains from the Cocktail LoungeGains from the Coc...
Goals and Principles of Power ControlGoals and Principles of Power Control The transmission power of the control BTSand M...
QuestionsQuestions What are the goals of the power control? What are the principles of the power control?
Chapter 1 Goals and Principles of Power ControlChapter 2 Categories and Arithmetic of Power ControlChapter 2 Categories an...
Chapter 2 Categories and Arithmetic of Power ControlChapter 2 Categories and Arithmetic of Power ControlSection 1 Categori...
Categories of Power ControlBased on the direction, we have:Reverse power controlForward power controlThe previous two ...
Chapter 2 Categories and Arithmetic of Power ControlChapter 2 Categories and Arithmetic of Power ControlSection 1 Categori...
Arithmetic of Power ControlArithmetic of Power ControlReverse Power Control The reverse power control is for the MS. The ...
Arithmetic of Power ControlArithmetic of Power ControlTheories of Reverse Open Loop Power ControlTheories of Reverse Open ...
Arithmetic of Power ControlArithmetic of Power ControlTheories of Reverse Open Loop Power ControlTheories of Reverse Open ...
Arithmetic of Power ControlArithmetic of Power Control The reverse power is estimated based onthe transmission amount of ...
Arithmetic of Power ControlArithmetic of Power ControlReverse Closed Loop Power ControlReverse Closed Loop Power ControlT...
Arithmetic of Power ControlArithmetic of Power Control Outer loop : The BSC obtains the setvalue of the Eb/Nt based on th...
Arithmetic of Power ControlArithmetic of Power ControlBTSChannel Assnmt. Msg.Origination MsgBase Sta. Acknlgmt. OrderTFC f...
Chapter 2 Categories and Arithmetic of Power ControlChapter 2 Categories and Arithmetic of Power ControlSection 1 Categori...
Arithmetic of Forward Power ControlArithmetic of Forward Power Control The power of the forward CDMA channel is shared by...
Arithmetic of Forward Power ControlArithmetic of Forward Power Control The forward power control is used forthe BTS Forw...
 You can collect statistics on forward channel quality in the followingmodes based on the system setting. Threshold mode...
The BSC can adjust the forward channel based on the EIB in the reverseservice channel frame (reverse link frame) reported ...
 Speed of calculating the EIB power control: 1 bit per 1 frame, thatis, 50 times/second. The good/bad frame is monitored...
Frame Quality Counter Power AdjustmentGood EIB_CNT counter = 0 Rise EIB_UP_STEP , EIB_CNTcounter =PWR_EIB_CNTEIB_CNT count...
 Outer loop: The MS computes theforward channel FER and thencompares with the target FER to getthe target Eb/Nt. Inner l...
Definition Standards of Radio Configuration andDefinition Standards of Radio Configuration andProtocol Version of the MSPr...
Application of the Power Control ArithmeticApplication of the Power Control Arithmetic Forward Power Control Is Based on ...
QuestionsQuestions What are the categories of the power control? What are the mapping relations between the forward powe...
Chapter 1 Goals and Principles of Power ControlChapter 2 Categories and Arithmetic of Power ControlChapter 3 Data Configur...
Data Configuration of Power ControlData Configuration of Power Control Parameters: NOM_PWR, INIT_PWR, PWR_STEP Brief Des...
 Parameter: RLGAIN_ADJ (link gain adjustment) Brief Description: After the access channel accesses the system, theinitia...
 Parameters:Minimum Eb/Nt value of the FCHMaximum Eb/Nt value of the FCHInitial Eb/Nt value of the FCH Brief Description...
Data Configuration of Power ControlData Configuration of Power ControlSynchronous Switch of the FCH Power In the soft han...
SummarySummary Goals and Principles of PowerControl Categories of Power Control Arithmetic of Power Control Data Confi...
CDMA 1x Introduction to Power Control Issue2.1
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CDMA 1x Introduction to Power Control Issue2.1

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One of the aims of the CDMA1X system is to maximize the number of its users. If each mobile station (MS) adjusts its transmitter power to minimize the signal noise received by the base transceiver station (BTS), the capacity of the system is maximized. Higher power brings higher interference and results in more capacity loss. Power control can adjust the transmission power of the MS and BTS, aiming to minimize the interference
After learning this course, you will learn the following:
The importance of the power control of the CDMA system
Categories and calculating theories of the power control
Data configuration of the power control
Chapter 1 Goals and Principles of Power Control
Chapter 2 Categories and Arithmetic of Power Control
Chapter 3 Data Configuration of Power Control
Each couple of customers is in a same room.
Each couple of customers speaks a language different from that spoken by other couples.
If the noise becomes louder, all the customers will raise their voices.
If the noise is too louder, the customers may go to other rooms.
The customer who speaks too loudly will affect the communication of others.
The transmission power of the control BTS and MS must ensure that the signal sent to the receiver through the complicated radio space can meet the threshold of correct demodulation.
When the first principle is satisfied, the transmission power of the BTS and MS is required to be lowered as much as possible to decrease the interference between users and best optimize the network performance.
The transmission power of the MS near the BTS is lower than that of the MS far from the BTS and of the MS in the fading areas.

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CDMA 1x Introduction to Power Control Issue2.1

  1. 1. Introduction to PowerControl of RG000003CDMA 1XISSUE 2.1
  2. 2. One of the aims of the CDMA1X system isto maximize the number of its users. If eachmobile station (MS) adjusts its transmitterpower to minimize the signal noise receivedby the base transceiver station (BTS), thecapacity of the system is maximized. Higherpower brings higher interference and resultsin more capacity loss. Power control canadjust the transmission power of the MSand BTS, aiming to minimize theinterference.Preface
  3. 3. GoalsGoalsAfter learning this course, you will learn thefollowing : The importance of the power control of theCDMA system Categories and calculating theories of thepower control Data configuration of the power control
  4. 4. Chapter 1 Goals and Principles of Power ControlChapter 1 Goals and Principles of Power ControlChapter 2 Categories and Arithmetic of Power ControlChapter 3 Data Configuration of Power ControlContents
  5. 5. Goals and Principles of Power ControlGoals and Principles of Power ControlCDMA Concept: cocktail loungeCDMA Concept: cocktail lounge  Each couple of customers isin a same room. Each couple of customersspeaks a language differentfrom that spoken by othercouples. If the noise becomes louder,all the customers will raisetheir voices. If the noise is too louder, thecustomers may go to otherrooms. The customer who speaks tooloudly will affect thecommunication of others.
  6. 6. Goals and Principles of Power ControlGoals and Principles of Power ControlGains from the Cocktail LoungeGains from the Cocktail Lounge The ground noise in current environment must be low enough.That is, the working frequency band of the system is notinterfered. The power control is very important in the CDMA system.The transmission power of the MS near the BTS is relativelylow and is high for the MS far from the BTS. All the MSshould transmit signals with as low power as possible, for thetransmission power of an MS is the noise for other MS. In the cocktail, each couple of customers speaks differentlanguage, which is like that using different codes todistinguish users.
  7. 7. Goals and Principles of Power ControlGoals and Principles of Power Control The transmission power of the control BTSand MS must ensure that the signal sent to thereceiver through the complicated radio spacecan meet the threshold of correctdemodulation. When the first principle is satisfied, thetransmission power of the BTS and MS isrequired to be lowered as much as possible todecrease the interference between users andbest optimize the network performance. The transmission power of the MS near theBTS is lower than that of the MS far from theBTS and of the MS in the fading areas.Basic PrinciplesBasic Principles
  8. 8. QuestionsQuestions What are the goals of the power control? What are the principles of the power control?
  9. 9. Chapter 1 Goals and Principles of Power ControlChapter 2 Categories and Arithmetic of Power ControlChapter 2 Categories and Arithmetic of Power ControlChapter 3 Data Configuration of Power ControlContents
  10. 10. Chapter 2 Categories and Arithmetic of Power ControlChapter 2 Categories and Arithmetic of Power ControlSection 1 Categories of Power ControlSection 2 Arithmetic of Reverse Power ControlSection 3 Arithmetic of Forward Power ControlContents
  11. 11. Categories of Power ControlBased on the direction, we have:Reverse power controlForward power controlThe previous two kinds of power control aredivided into the following respectively :Reverse power controlReverse open loop power controlReverse closed loop power controlForward power controlPower control based on the measurementreportEIB power controlForward quick power control
  12. 12. Chapter 2 Categories and Arithmetic of Power ControlChapter 2 Categories and Arithmetic of Power ControlSection 1 Categories of Power ControlSection 2 Arithmetic of Reverse Power ControlSection 2 Arithmetic of Reverse Power ControlSection 3 Arithmetic of Forward Power ControlContents
  13. 13. Arithmetic of Power ControlArithmetic of Power ControlReverse Power Control The reverse power control is for the MS. The major aim is toensure that the signals received by the BTS receiver can reach theminimize required Eb/Nt value through the adjustment of thetransmission power of the MS. Compared with the forward power control, the requirements forthe reverse power control is higher and the process is morecomplicated: Eb/Nt=bit energy/effective noise power spectral density Ec/Io=chip energy/carrier frequency total power spectraldensity
  14. 14. Arithmetic of Power ControlArithmetic of Power ControlTheories of Reverse Open Loop Power ControlTheories of Reverse Open Loop Power Control The reverse open loop power control bases on the hypothesis that the lossof the forward link and the reverse link is similar. Based on this hypothesis, the MS estimates the forward link lossaccording to the total received power and then estimates the transmissionpower of the MS.Transmission power of the MSForward link loss (dB)||Reverse link loss (dB)Transmission powerof the BTSReceipt power of the BTSDemodulation of theBTSReverse link loss (dB)=Transmission power of the BTS (dBm)-Receiptpower of the MS (dBm)
  15. 15. Arithmetic of Power ControlArithmetic of Power ControlTheories of Reverse Open Loop Power ControlTheories of Reverse Open Loop Power ControlTx_power = - MeanRx_Power + offsetpower + NOM_PWR –16* NOM_PWR_EXTs + INIT_PWR+ interference correctionⅠⅢⅡⅠ :Ⅱ :Ⅲ :Tx_power= Ⅰ + PWR_STEPTx_power= Ⅱ + PWR_STEPACHFCH ( 95 ) or PICH ( 2000 )Imported toⅣFCH ( 2000 )Ⅳ :Ⅴ :Tx_power= Ⅲ + RLGAIN_ADJsTx_power = Ⅳ + RLGAIN_TRAFFIC_PILOT+OTHER1The offset power is a constant defined in the protocol and related to BandClass.RC and so on.V
  16. 16. Arithmetic of Power ControlArithmetic of Power Control The reverse power is estimated based onthe transmission amount of the forwardlink, but high error will occur due to theirrelevance of forward and reverse links. The received power is affected byneighbor BTSs and thus the high erroroccurs at the edge of the district. The open loop power is the estimatedvalue that is not precise enough and needsthe closed loop to rectify the value.Disadvantages of Reverse Open Loop Power ControlDisadvantages of Reverse Open Loop Power Control
  17. 17. Arithmetic of Power ControlArithmetic of Power ControlReverse Closed Loop Power ControlReverse Closed Loop Power ControlThe closed loop rectification indicates that based on theestimation of the open loop, the MS can quickly rectify itstransmission power (800 times per second) according topower control instruction received in the forward channel.The closed loop verification is divided into:inner loopouter loopAfter the closed loop powercontrol takes effect, thetransmission power of the MSis obtained based on reverseopen loop estimation andclosed loop adjustment.
  18. 18. Arithmetic of Power ControlArithmetic of Power Control Outer loop : The BSC obtains the setvalue of the Eb/Nt based on the currentFER Inner loop : The BTS fills the power bit inthe traffic frame based on the currentreverse Eb/Nt The reverse power control bits are sentthrough the forward service channel.Reverse Closed Loop Power ControlReverse Closed Loop Power Control
  19. 19. Arithmetic of Power ControlArithmetic of Power ControlBTSChannel Assnmt. Msg.Origination MsgBase Sta. Acknlgmt. OrderTFC frames of 000sTFC preamble of 000sBase Sta. Acknlgmt. OrderMobile Sta. Ackngmt. OrderService Connect Msg.Svc. Connect Complete MsgBase Sta. Acknlgmt. OrderCall is Established!MSProbingACCESSPAGINGFW TFCPAGINGRV TFCFW FCRV TFCFW TFCRV TFCFW TFCSuccessful Access AttemptStart point of the open looppower controlStart point of the closed looppower control 
  20. 20. Chapter 2 Categories and Arithmetic of Power ControlChapter 2 Categories and Arithmetic of Power ControlSection 1 Categories of Power ControlSection 2 Arithmetic of Reverse Power ControlSection 3 Arithmetic of Forward Power ControlSection 3 Arithmetic of Forward Power ControlContents
  21. 21. Arithmetic of Forward Power ControlArithmetic of Forward Power Control The power of the forward CDMA channel is shared by the pilotfrequency, synchronization, paging and service channels. The intensity of the signal varies with the changes of distancefrom the MS to the BTS. As the result, it is better to control thepower distribution for each traffic channel. The standard specifies that the MS must monitor the quality ofthe forward traffic channel. After receiving the instructions fromthe BTS, the MS sends the messages to the MS. The closed loopprocess is similar with the reverse power control.Features of Forward Power ControlFeatures of Forward Power Control
  22. 22. Arithmetic of Forward Power ControlArithmetic of Forward Power Control The forward power control is used forthe BTS Forward power control based onthe measurement report EIB Power control Forward quick power controlCategories of the Forward Power ControlCategories of the Forward Power Control
  23. 23.  You can collect statistics on forward channel quality in the followingmodes based on the system setting. Threshold mode: When the number of the frame errors reaches thethreshold set by the system, the MS reports the PMRM message tothe BTS. In this way, the signals are decreased and the efficiencyimproved. Cycle mode: When the number of the frames reaches the cycleframes set by the system, the MS reports the PMRM messages tothe BTS. The MS can support the two modes at the same time. For sake ofconvenient processing, the system does not support two modes at thesame time at present.Arithmetic of Forward Power ControlArithmetic of Forward Power ControlForward Power Control Based on Measurement ReportForward Power Control Based on Measurement Report
  24. 24. The BSC can adjust the forward channel based on the EIB in the reverseservice channel frame (reverse link frame) reported by the MS. TheEIB indicates erasure indicator bit and is used to judge the good andbad frames.Note:From the version3 of the protocol on, the reverse traffic channel frames ofRateSet2 contains the EIB.EBI setting: When it is set to 0, it indicates that the frame is good and haspassed the CRC verification of the physical layer; if it is set to 1, itindicates that the frame is bad and has not passed the CRC verification.Arithmetic of Forward Power ControlArithmetic of Forward Power ControlTheories of EIB Forward Power ControlTheories of EIB Forward Power Control
  25. 25.  Speed of calculating the EIB power control: 1 bit per 1 frame, thatis, 50 times/second. The good/bad frame is monitored on the F-FCH, the Arithmeticdelay of the EIB power control is 2 frame in general. To ensure the processing delay of different MSs, the EIB powercontrol is put in the first bit of the reverse service frame.Arithmetic of Forward Power ControlArithmetic of Forward Power ControlTheories of EIB Forward Power ControlTheories of EIB Forward Power Controli-1 i i+1 i+2ReceivedFrames onForwardFundamental orDedicated ControlChannel20 msi-1 i i+1 i+2Reverse PowerControlSubchannel20 msPower control bits set to 1 forbad frame(s) or 0 for good frame(s)i+2
  26. 26. Frame Quality Counter Power AdjustmentGood EIB_CNT counter = 0 Rise EIB_UP_STEP , EIB_CNTcounter =PWR_EIB_CNTEIB_CNT counter != 0 Unchanged powerBad EIB_CNT counter = 0 Fall EIB_DWNS_STEPEIB_CNT counter != 0 Fall EIB_DWNB_STEPArithmetic of Forward Power ControlArithmetic of Forward Power ControlTheories of EIB Forward Power ControlTheories of EIB Forward Power Control
  27. 27.  Outer loop: The MS computes theforward channel FER and thencompares with the target FER to getthe target Eb/Nt. Inner loop: The MS fills the power bitin the subchannel of the reversepower control by comparing thetarget Eb/Nt with the measuredEb/Nt. The forward quick power control bitis sent through the reverse pilotfrequency channel.Arithmetic of Forward Power ControlArithmetic of Forward Power ControlTheories of Forward Quick Power ControlTheories of Forward Quick Power Control
  28. 28. Definition Standards of Radio Configuration andDefinition Standards of Radio Configuration andProtocol Version of the MSProtocol Version of the MS For the IS2000 and IS95/95B are backward compatible, the RateSet1 and Rate Set2 (as a subset of the IS2000) corresponds to RC1and RC2.Radio ConfigurationProtocol Version of the MSProtocol version of the MS:1-2:IS95, 3:IS95A,4-5:IS95B, 6:20001X
  29. 29. Application of the Power Control ArithmeticApplication of the Power Control Arithmetic Forward Power Control Is Based on the CDMA Standards: The MS with version 2-5 is allocated with the RC1 channel andadopts the measurement report power control. The MS with version 3-5 is allocated with the RC2 channel andadopts the EIB power control (prior choice) and themeasurement report power control as well. The MS with version later than 6 (including 6) adopts forwardquick power control (prior choice) and measurement reportand EIB control as well. Application of the Reverse Power Control The MS with version 2-7 adopts the same reverse powercontrol Arithmetic (open loop and closed loop).At present, the Huawei system automatically chooses the power controlArithmetic based on the protocol versions of the MS and radioconfiguration.
  30. 30. QuestionsQuestions What are the categories of the power control? What are the mapping relations between the forward power controland RC and the protocol version of the mobile phone? What are the theories of the forward quick power control andreverse quick power control?
  31. 31. Chapter 1 Goals and Principles of Power ControlChapter 2 Categories and Arithmetic of Power ControlChapter 3 Data Configuration of Power ControlChapter 3 Data Configuration of Power ControlContents
  32. 32. Data Configuration of Power ControlData Configuration of Power Control Parameters: NOM_PWR, INIT_PWR, PWR_STEP Brief Description: These parameters affect the power estimation of open loop powercontrol. Their influence begins at the first access probe transmission. They greatlyaffect the access process and call establishment. For details, see CDMA 1x BSSParameter Configuration Guide and the previously described contents. Relevant Message: APM Balance Setting: If the values of the parameters are set too high, the parameters willhave great impact on the reverse capacity and redundant power is generated. If thevalues are set too low, you may have to try many times before having the mobile phoneaccessed to the channel and the access may even fail. Supplement: Parameter NOW_PWR and parameter INI_PWR has the same impact onthe first accessed probe. They are different from the perspective of physics. The effectof their impact on the later probes differs. Command Line: MOD APM
  33. 33.  Parameter: RLGAIN_ADJ (link gain adjustment) Brief Description: After the access channel accesses the system, theinitial power (the reverse pilot frequency power for the IS2000) of thetraffic channel = the power of the current access channel + the value ofthe parameter Relevant Message: ECAM Balance Setting: The greater the parameter value is, the higher are thetransmission quality during the initial period of the call and the establishrate of the call. However the parameter will have impact on the systemcapacity and increase the power consumption of the mobile phone. Command Line: MOD RCLPCData Configuration of Power ControlData Configuration of Power Control
  34. 34.  Parameters:Minimum Eb/Nt value of the FCHMaximum Eb/Nt value of the FCHInitial Eb/Nt value of the FCH Brief Description: This group of parameters respectively indicatethe minimize, maximize and initial set values of the forward FCHouter loop power control of the mobile phone. Relevant Information: ECAM Balance Setting: These values need to be balanced between thevoice quality, call drop rate and the forward system capacity. Ifthey are set high, the voice quality will be improved and the calldrop rate decreased but decrease the forward capacity. Command Line: MOD FFASTPCData Configuration of Power ControlData Configuration of Power Control
  35. 35. Data Configuration of Power ControlData Configuration of Power ControlSynchronous Switch of the FCH Power In the soft handoff, the ratios between the traffic channel powers ofdifferent branches and the forward pilot channel power are the same.The traffic channel consists of the FCH and the SCH. The synchronous switch is suggested to be on without A3/A7 softhandoff. The synchronous switch is suggested to be off with A3/A7 softhandoff, so are the BSC and the BTS sides.NoteFor V2R2, we can switch on the Power Synchronous Switchafter approved
  36. 36. SummarySummary Goals and Principles of PowerControl Categories of Power Control Arithmetic of Power Control Data Configuration of Power ControlContentsContents

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