ADC Telecommunications DLC1902B Digivance® LRCS 1900 MHz, 20-Watt LPA User Manual 75158

ADC Telecommunications Inc Digivance® LRCS 1900 MHz, 20-Watt LPA 75158

User manual 5

ADCP-75-158 • Issue 1 • July 2003 • Section 4: OperationPage 4-7© 2003, ADC Telecommunications, Inc.Figure 4-4. Select Control Program File Window4. Select the first file to download and click on the OK button. 5. Click on the HOST Load button (see Figure 4-3) to start the download. 6. Repeat steps 4 and 5 for each file that requires downloading. 7. Repeat steps 2 through 5 for the REMOTE. 2.3 Determine Forward Path Input Signal LevelThe level of the composite RF input signal at the FORWARD RF IN port at the HU will varydepending on the type of BTS, the cable loss, the number of channels present, and the requiredforward path composite power. If maximum composite RF output is required, the signal level ofthe composite forward path RF signal at the HU forward path input must be adjusted to fallwithin a range of –9 to –40 dBm. If the signal level is not within this range, it must be adjustedto fall within this range through the use of an external attenuator capable of handling the BTSforward path output power. If using the Conditioning Panel or Duplexing Panel, refer to the Digivance 800 and 1900 MHzInterface Panels User Manual (ADCP-75-147) for the procedures for measuring and adjustingthe input RF signal level at the HU. If connecting a single HU to a single BTS, use the followingprocedure to measure and adjust the input RF signal level at the HU: 1. Connect a spectrum analyzer or power meter to the forward path output port of the BTS.The required signal levels and test points are shown in Figure 4-5. 2. If using a spectrum analyzer, proceed to step 3. If using a power meter, measure thecomposite signal power from the BTS and then proceed to step 5.3. Measure the RF level of a single carrier, such as the control channel, in dBm. Make surethe resolution bandwidth of the spectrum analyzer is 30 kHz. Maximum power in anychannel should not exceed 5W (+37 dB). Note: Check the input rating of the test equipment and the output rating of the BTS. Toavoid burning out the spectrum analyzer or power meter, it may be necessary to insert a30 dB 100W (or similar) attenuator between the BTS and test equipment.
ADCP-75-158 • Issue 1 • July 2003 • Section 4: OperationPage 4-8© 2003, ADC Telecommunications, Inc.4. Calculate the total composite signal power from the BTS using the following formula: Ptot = Pc + 10Log N – (see Note)Where,Ptot is the total composite power in dBmPc is the power per carrier in dBm as measured in step 3, andN is the total number of channels. 5. Determine the total cable loss that is imposed by the forward path coaxial cable that linksthe BTS to the HU and also any insertion loss imposed by splitters or combiners. 6. Subtract the total cable loss and any insertion losses from the total composite powercalculated in step 4. 7. Subtract –25 (midpoint of the required range) from the value determined in step 6. Thedifference (which should be positive) equals the value of the external attenuator that isrequired to reduce the forward path signal level to fall within the required range. Thefollowing formula outlines the required calculations for steps 6 and 7: Ptot – (Cable and insertion loss) – (–25) = Value of external attenuator required8. Select an attenuator that is as close to the value calculated in step 7 as possible. Select avalue that will adjust the signal level of the composite input signal to fall within thespecified range. 9. Install the external attenuator in the coaxial cable that is connected to the FORWARD RFIN port at the HU. 10. Subtract the value of the external attenuator used in step 9 from the total composite signalpower (Ptot) and record the result. This value will be required when setting the attenuationof the HU’s internal forward attenuator. Note: If calculating the composite power for a CDMA system, reduce the initial result by16.23 dB. Note: If the input signal level is already within the required range of –9 to –40 dBm, thenno external attenuator is required. Caution: The Host Unit can be damaged if it is overdriven by the BTS. Always install anexternal protective attenuator at the Host Unit FORWARD RF IN port if the forward pathcomposite input signal level is greater than –9 dBm.
ADCP-75-158 • Issue 1 • July 2003 • Section 4: OperationPage 4-9© 2003, ADC Telecommunications, Inc.Figure 4-5. Signal Levels, Test Points, and AdjustmentsINPUT SIGNAL LEVEL(-25 dBm TYPICALCOMPOSITE FORFULL POWER)HOST UNITPRIMARYANTENNALPAREMOTE UNITBASETRANSCEIVER STATION17000-CEXTERNALATTENUATORTRANS-MITTERSRECEIVERS0 to 31 dBATTENUATOR(HOST REV ATT)0 to 31 dBATTENUATOR(HOST FWD ATT)RF, OPTICS,AND CONTROL0 to 31 dBATTENUATOR(REMOTE FWD ATT)OPTICAL LINKRF, OPTICS,AND CONTROLDUPLEXERADJUSTMENTS TO INPUTSIGNAL LEVEL AS SET BY HOSTFORWARD PATH ATTENUATORADJUSTMENTS TO OUTPUTSIGNAL LEVEL AS SET BY HOSTREVERSE PATH ATTENUATORMAXIMUM OUTPUT SIGNALLEVEL AT STM ANTENNA PORTADJUSTMENTS TOOUTPUT SIGNAL LEVELAS SET BY THE REMOTEFORWARD ATTENUATOR
ADCP-75-158 • Issue 1 • July 2003 • Section 4: OperationPage 4-10© 2003, ADC Telecommunications, Inc.2.4 Enter Site Name and Site NumberAll HU’s and RU’s are programmed with the same site name and site number. It is thereforenecessary to assign a unique site name and site number to the HU and RU before they can beconnected to the same CAN. Use the following procedure to assign a unique site name andnumber to each HU and RU system:1. Click on the HOST Config tab and on the REMOTE Config tab. The HOST Configdisplay and the REMOTE Config display will open within the EMS main window asshown in Figure 4-6. Figure 4-6. HOST and REMOTE Config Displays2. Right-click on the HOST Site Name field (see Figure 4-6). The Site Name pop-up screenwill open as shown in Figure 4-7. Enter a unique name for the HOST. The name may be upto 32 characters long and must not contain any spaces. The name may include numbers,punctuation, and upper or lower case letters and must always begin with a letter. Click onOK to close the screen and make the changes take effect. Figure 4-7. HOST Site Name Pop-Up ScreenHOST Site NumberHOST Site NameREMOTE Site Number(Entered automaticallywhen the HOST sitenumber is selected)REMOTE Site NameRight-Click on thepoint shown to openpop-up screen
ADCP-75-158 • Issue 1 • July 2003 • Section 4: OperationPage 4-11© 2003, ADC Telecommunications, Inc.3. Right-click on the HOST Site Number (see Figure 4-6). The Site Number pop-up screenwill open. Enter any number between 1 and 24 and then click on OK to close the screenand make the changes take effect. 4. Check the REMOTE Site Number field (see Figure 4-6). The REMOTE Site Numberdoes not have to be entered. When the HOST Site Number is entered, the system willautomatically enter the same number for the REMOTE Site Number. 5. Right-click on the REMOTE Site Name field (see Figure 4-6). The Site Name pop-upscreen will open. Enter a unique name for the REMOTE. The name may be up to 32characters long and must not contain any spaces. The name may include numbers,punctuation, and upper or lower case letters and must always begin with a letter. Click onOK to close the screen and make the changes take effect. 6. Open the Tools menu at the top of the main window and then select Refresh Catalog tomake the new Host and Remote site names appear in the View menu. 2.5 Enter Host Forward AttenuationThe HU internal forward path attenuator setting determines the maximum composite outputsignal level at the STM antenna port. The appropriate attenuation value for any particularsystem is based on the number of channels the system is transporting and the level of thecomposite forward path signal input at the HU’s FORWARD RF IN port. The maximum outputpower that can be provided by the system is 40.5 dBm (11 Watts). The total forward path gainthat is provided by the system (with host and remote forward attenuators set to 0 dB) is 80.5dBm. Use the following procedure to set the forward path attenuation to provide the maximumcomposite output signal level: 1. Click on the HOST RF tab. The HOST RF display will open within the EMS mainwindow as shown in Figure 4-8. 2. Right-click on the Host Fwd Att section of the display (see Figure 4-8). The Host FwdAtt pop-up screen will open as shown in Figure 4-9. 3. Obtain the value of the total composite input signal level as determined in step 10 ofSection 2.3. 4. Determine the appropriate value to enter for the Host forward path attenuator bysubtracting the required system output level (per system design plan) from 80.5 (the totalsystem gain) and then adding the composite input signal level. The result (see samplecalculation) is the amount of attenuation required. Atten Required = 80.5 – (Required System Output Power) + (Composite Input Power)5. Enter the attenuation value and click OK to close the pop-up screen and to make thechanges take effect.
ADCP-75-158 • Issue 1 • July 2003 • Section 4: OperationPage 4-12© 2003, ADC Telecommunications, Inc.Figure 4-8. HOST RF DisplayFigure 4-9. Host Fwd Att Pop-Up Screen2.6 Determine Output Signal Level at STM Antenna PortThe RF output signal level should be measured at the STM ANTENNA port to verify thatmaximum composite signal level is at the required level. Use the following procedure todetermine the power level:1. Verify that RF ON/OFF switch on the LPA in the OFF position. 2. Disconnect the antenna cable from the STM ANTENNA port. 3. Connect a spectrum analyzer or RF power meter to the STM ANTENNA port. (Check theinput rating of the test equipment. Insert a 30 dB 100 W attenuator if necessary.) Right-click hereto open Host FwdAtt pop-up screen
ADCP-75-158 • Issue 1 • July 2003 • Section 4: OperationPage 4-13© 2003, ADC Telecommunications, Inc.4. Place the RF ON/OFF switch on the LPA in the ON position. 5. If using a spectrum analyzer, proceed to step 6. If using a power meter, measure thecomposite signal power from the STM and then proceed to step 8.6. Measure the RF level of a single carrier, such as the control channel, in dBm. Make surethe resolution bandwidth of the spectrum analyzer is 30 kHz. 7. Calculate the total composite signal power using the following formula: Ptot = Pc + 10Log N – (see Note)Where,Ptot is the total composite power in dBmPc is the power per carrier in dBm as measured in step 6, andN is the total number of channels. 8. Record the result measured in step 5 or calculated in step 7. 9. Place the MUTE/NORM/RESET switch on the LPA in the OFF position. 10. Disconnect the spectrum analyzer or RF power meter from the STM ANTENNA port. 11. Re-connect the antenna cable to the STM ANTENNA port. 2.7 Enter Remote Forward AttenuationThe STM internal forward path attenuator setting is used to reduce the power level of thecomposite output signal level at the STM antenna port. The maximum composite output signallevel at the STM antenna port is set using the Host internal forward attenuator (see Section 2.4).However, component variations may result in the output power at the STM antenna port beingslightly above or below the required power per channel. If this is the case, the STM forwardattenuator may be used in conjunction with the Host forward attenuator to add or removeattenuation to produce the required output signal level. If less power is required, the STMforward attenuator may be used to reduce the power level. The default setting is 0 dB. Use thefollowing procedure to change the STM forward attenuation: 1. Click on the REMOTE LPA tab. The REMOTE LPA display will open within the EMSmain window as shown in Figure 4-10. Note: If calculating the composite power for a CDMA system, reduce the initial result by16.23 dB. Note: To comply with Maximum Permissible Exposure (MPE) requirements, themaximum composite output from the antenna cannot exceed 1000 Watts EIRP and theantenna must be permanently installed in a fixed location that provides at least 6 meters(20 feet) of separation from all persons.
ADCP-75-158 • Issue 1 • July 2003 • Section 4: OperationPage 4-14© 2003, ADC Telecommunications, Inc.Figure 4-10. REMOTE LPA Display2. Check the level of the RF output signal (as determined in Section 2.6) against the systemdesign plan specifications. Table 4-1 shows the output signal level required to provide 5watts per channel for systems with 1 to 2 channels. The maximum output signal levelpermitted for the system is 40.5 dBm (11 Watts). 3. Determine if more or less attenuation is required to produce the required output signal level. 4. Right-click on the Remote Fwd Att section of the display (see Figure 4-10). The RemoteFwd Att pop-up screen will open as shown in Figure 4-11. 5. Enter the required attenuation value and click OK to close the pop-up screen and to makethe changes take effect. Table 4-1. Composite Output Signal LevelsNUMBER OF CHANNELSOUTPUT SIGNAL LEVEL REQUIRED TO PROVIDE 5 WATTS PER CHANNEL 137 dBm240 dBmWhen there are three or more channels, each channel will always be less than 5 watts since the system has a maximum power output of 11 watts (40.5 dBm).Right-click here toopen the Remote FwdAtt pop-up screenRF output signal level
ADCP-75-158 • Issue 1 • July 2003 • Section 4: OperationPage 4-15© 2003, ADC Telecommunications, Inc.Figure 4-11. Remote Fwd Att Pop-Up Screen6. Verify that the appropriate RF output signal level appears in the RF Pwr-VSWR Lowsection (see Figure 4-10). This is primarily a reference value and should not take the placeof external test equipment when determining the power level of the composite RF outputsignal. Depending on the modulation type and number of channels, the EMS software mayreport a power level that is higher or lower than the actual RF output signal. 2.8 Enter Host Reverse AttenuationThe level of the RF signal that should be input to the BTS will vary depending on the type ofBTS, the receive distribution, and the number of channels present. To interface with the BTS,the reverse path signal level must be adjusted to provide the signal level required by the BTS.The HU provides from –1 dB of gain to +30 dB of gain in the reverse path. Use the followingprocedure to set the reverse path gain:1. Check the BTS manufacturer’s specifications to determine the composite signal levelrequired at the BTS reverse path input port. 2. Determine the overall gain and loss imposed on the signal by the antenna, antenna cable,and by the cables that connect the HU to the BTS. 3. Determine the amount of gain required to raise the reverse path signal to the level requiredat the BTS. 4. Click on the HOST RF tab. The HOST RF display will open within the EMS mainwindow as shown in Figure 4-12. Note: To comply with Maximum Permissible Exposure (MPE) requirements, themaximum composite output from the antenna cannot exceed 1000 Watts EIRP and theantenna must be permanently installed in a fixed location that provides at least 6 meters(20 feet) of separation from all persons.
ADCP-75-158 • Issue 1 • July 2003 • Section 4: OperationPage 4-16© 2003, ADC Telecommunications, Inc.Figure 4-12. HOST RF Display5. Right-click on the Host Rev Att section of the display (see Figure 4-12). The Host RevAtt pop-up screen will open as shown in Figure 4-13. Figure 4-13. Host Rev Att Pop-Up Screen6. Enter the attenuation value that will provide the required gain. Refer to Table 4-2 for theattenuation values and the corresponding gain (nominal) values. 7. Click OK to close the pop-up screen and to make the changes take effect.Right-click here toopen the Host Rev Attpop-up screenRight-click here toopen the Host Div RevAtt pop-up screen
ADCP-75-158 • Issue 1 • July 2003 • Section 4: OperationPage 4-17© 2003, ADC Telecommunications, Inc.2.9 Enter Host Forward and Reverse DelayThe forward and reverse delay function allows entry of from 0 to 63 µsec of delay in theforward and reverse paths. This feature is used when multiple systems are used to transport thesame channel and there is a significant difference in the path delay between systems. Additionaldelay may be entered to balance the overall system delay. The amount of delay required must becalculated by the RF engineer and should be included in the system design plan. The defaultsetting is 0 µsec. Use the following procedure to change the forward and reverse path delay: 1. Click on the HOST RF tab. The HOST RF display will open within the EMS mainwindow as shown in Figure 4-14. Figure 4-14. HOST RF DisplayTable 4-2. Reverse Path Attenuation Settings and Nominal Gain ProvidedATTENUATION SETTINGGAIN PROVIDEDATTENUATION SETTINGGAIN PROVIDEDATTENUATION SETTINGGAIN PROVIDED 0 dB →30 dB 11 dB →19 dB 22 dB →8 dB1 dB 29 dB 12 dB 18 dB 23 dB 7 dB2 dB 28 dB 13 dB 17 dB 24 dB 6 dB3 dB 27 dB 14 dB 16 dB 25 dB 5 dB4 dB 26 dB 15 dB 15 dB 26 dB 4 dB5 dB 25 dB 16 dB 14 dB 27 dB 3 dB6 dB 24 dB 17 dB 13 dB 28 dB 2 dB7 dB 23 dB 18 dB 12 dB 29 dB 1 dB8 dB 22 dB 19 dB 11 dB 30 dB 0 dB9 dB 21 dB 20 dB 10 dB 31 dB –1 dB10 dB 20 dB 21 dB 9 dB -- --Right-click here toopen the Host FwdDelay pop-up screenRight-click here toopen the Host RevDelay pop-up screenRight-click here toopen the Host Div RevDelay pop-up screen

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