Troubleshooting Hints | Agilent Technologies E4406A manual

Making Measurements

Making the Adjacent Channel Power (ACP) Measurement

Troubleshooting Hints

This adjacent channel power ratio measurement can reveal degraded or defective parts in the transmitter section of the UUT. The following examples are those areas to be checked further.

•Some faults in the DC power supply control of the transmitter power amplifier, RF power controller of the pre-power amplifier stage, or I/Q control of the baseband stage.

•Some degradation in the gain and output power level of the amplifier due to the degraded gain control and/or increased distortion.

•Some degradation of the amplifier linearity and other performance characteristics.

Power amplifiers are one of the final stage elements of a base or mobile transmitter and are a critical part of meeting the important power and spectral efficiency specifications. Since ACP measures the spectral response of the amplifier to a complex wideband signal, it is a key measurement linking amplifier linearity and other performance characteristics to the stringent system specifications.

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Chapter 4

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Agilent Technologies E4406A manual Troubleshooting Hints

Contents

Agilent Technologies E4406A VSA Series User’s GuideTransmitter Tester Safety Information LIMITATION OF WARRANTY WarrantyEXCLUSIVE REMEDIES Page Using System Features ContentsGetting Started 3.Setting the Mode Contents4. Making Measurements Contents Changing the Measurement Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133 Changing the Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 Using the Marker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 Troubleshooting Hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135 Making the Power Stat CCDF Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 Measurement Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 Making the Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 Changing the Measurement Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138 Changing the View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 Changing the Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139 Using the Markers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140 Troubleshooting Hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140 Service Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141 Timebase Frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 Measurement Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 Test Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143 50 MHz Amplitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 Measurement Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 Test Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 Measurement Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 Test Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146 Front Panel Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148 Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148 Test Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149 Troubleshooting Hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149 Service Power vs. Time Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150 Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150 Using Baseband I/Q Inputs Option B7C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151 What are Baseband I/Q Inputs? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152 What are Baseband I/Q Signals? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153 Why Make Measurements at Baseband?. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153 Making Measurements with Baseband I/Q Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154 Baseband I/Q Measurement Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155 Selecting Input Probes for Baseband Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156 Selecting Baseband I/Q Inputs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159 Selecting Baseband I/Q Input Connectors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159 Setting Up Baseband I/Q Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161 Baseband I/Q Measurement Views . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165 Baseband I/Q Measurement Result Examples 5. If You Have a Problem Contents6. Options and Accessories List of Keys List of Keys Front Panel Test List of Keys Reference List of Keys Getting Started Topics include Standard Documentation TablePart Description Measurement Option TablePersonality Documentation Part Description Description URL for the Latest VSA Transmitter Tester UpdateUnderstanding Digital Communications Measurements Agilent Part Getting Started Updating the FirmwareChapter Step Making a MeasurementSetup Keys Primary Key Front Panel Keys Context Dependency System Meas View/Setup Trace Service GSM cdmaOne Waveform Time DomainSpectrum Freq Domain Spurious Close Channel Power MEASURESetup Marker Channel PowerSetup Getting Started Meas View/Setup Trace Service GSM cdmaOne Waveform Time DomainSpectrum Freq Domain Spurious Close Channel Power MEASURESetup Front Panel Description 2.Control keys Getting Started Front Panel Description Chapter 6.Mode keys select the measurement mode and mode parameters See page 83 for more detail Getting Started Front Panel Description Chapter 12.Floppy Disk Drive. The floppy disk drive accepts 1.44 megabyte disks. For an explanation of the operation of the floppy disc drive see the Using Print Keys section on page be implemented with a future firmware update Getting Started Rear Panel Description Rear Panel DescriptionChapter measurements. The external trigger accepts an 11. PARALLEL The PARALLEL connection supports remote printing Display Annotation Measurement Bar. Displays information about ESec even second clock - The green ESec Installing Optional Measurement Personalities Available Personality Options Key Path Loading the Optional PersonalityRequired Information Available Personality Options Viewing a License Key Installing a License Key Using the Uninstall KeyPage Figure 1-5HP 24542U Cable Cables for Connecting to the Serial Port RS-232Figure 1-6HP F1047-80002Cable Figure Cables for Connecting to the Serial Port RS-232Figure 1-7HP 24542G/H Cable HP 92219J Cable Figure 1-11HP C2913A/C2914A Cable Cables for Connecting to the Serial Port RS-232Figure 1-10HP 24542M Modem Cable Figure 1-12Mouse Adapter typical Figure 1-14HP 24542U Cable with 5181-6640Adapter Cables for Connecting to the Serial Port RS-232Figure 1-13HP 24542U Cable with 5181-6641Adapter Figure 1-15HP 24542U Cable with 5181-6642Adapter Figure 1-16HP 24542U Cable with 5181-6639Adapter Figure 1-19HP F1047-80002Cable with 5181-6642Adapter Safety Considerations Instrument Installation Instrument Operation and Maintenance Safety Considerations for Service Personnel Getting Started Safety Considerations Chapter Using System Features Using System Keys Install and Uninstall Key Access Locations Key LocationsTable Key Locations Using System FeaturesChapter Using System Features Key Access LocationsTable Key Access Path Key Access Path Key Access LocationsUsing System Features Key Locations Table Key Access Path Key Access LocationsUsing System Features Key Locations Table Key Access Path Key Access LocationsUsing System Features Table Key Access Path Key Access LocationsUsing System Features Key Locations Input/Input Port Using System FeaturesKey Locations Chapter Using System Features Key Locations Chapter Key Access Path Key Access LocationsUsing System Features Key Locations Using Print and Print Setup Functions Printing a Displayed Screen Front Panel Key language default towhen Color Print is set to Level Using Print and Print Setup Functions Using System FeaturesChapter shown below are selectedthe six screen files available only when Loading a State Using File and Save KeysSaving a State Level Using the Alpha Editor KeysLevel Level Using Input/Output Configuration Keys Configuring I/O •SCPI LAN - Accesses the following keys Front Panel File SystemReference Level •10 MHz Out - Activates, or deactivates, the 10 MHz out signal on the rear panel of the instrument. The 10 MHz out can be used to lock other test equipment to the same frequency reference that is used by the transmitter tester. Once activated, the 10 MHz out feature is persistent, so if it is set to On it will remain on, even if the instrument has been preset, or powered off and then on Restore System Defaults Using System Configuration and Alignment KeysShow Errors features are described in the service guide Show System Show System Displays Using System FeaturesUsing System Configuration and Alignment Keys Chapter Using System Configuration and Alignment Keys System LocalUsing System Features Chapter Level AlignmentFront Level remains constant Using System Configuration and Alignment Keys Using System FeaturesChapter Using System Configuration and Alignment Keys Using System FeaturesChapter Setting the Mode Setting the Mode Selecting a Mode Selecting a ModeChapter Mode Setup Input Keys Adjust Input Attenuation and Input Power Adjust the IF Align Signal Trigger Keys •RF Burst Wideband •Video IF Envlp Selecting the Frequency/Channel •Sync Source key menu 4 Making Measurements Basic Measurements Using Measure Keys Initial SetupPreparing for Measurements Measurement Control Measurement SetupAveraging Voltage Avg - The voltage is averaged Trigger Source •Trace Display Changing the View•Typical Measurement Windows Span / X Scale Keys •Amplitude / Y Scale Keys Trace Using MarkersMarkers Marker Functions Search Marker Measurement Method Making the Spectrum Frequency Domain MeasurementPurpose Making the Measurement Results Table Changing the Measurement SetupSpectrum Frequency Domain Measurement Defaults Making Measurements measurement data Auto Auto Peak - Select this to set the ADC range automatically to the peak signal level. Auto peak is a compromise that works well for both CW and burst signals Making the Spectrum Frequency Domain Measurement Changing the ViewMaking Measurements Chapter Figure 4-4Spectrum Measurement - I/Q Polar View Changing the Display Changing the Linear Spectrum Display Changing the I or Q Waveform Window Making Measurements Changing the I/Q Polar WindowSelecting Displayed Traces Within Windows Making the Spectrum Frequency Domain Measurement Using the Markers Measuring Band Power Making the Spectrum Frequency Domain Measurement Troubleshooting HintsMaking Measurements Chapter Measurement Method Making the Waveform Time Domain MeasurementPurpose Making the Measurement Input signal: cdma2000 Rev 8, SR1, 9 Channel Results Making the Waveform Time Domain Measurement Making MeasurementsChapter Waveform Time Domain Measurement Defaults Changing the Measurement SetupTable In addition, the following parameters can be modified Making the Waveform Time Domain Measurement Making MeasurementsChapter Changing the View Meas Setup: View/Trace = I/Q Waveform View Changing the Display Figure 4-9Waveform Measurement - I/Q Polar View Making the Waveform Time Domain Measurement Making MeasurementsChapter Using the Markers •Off - Allows you to turn off the selected marker Troubleshooting Hints differing values for the maximum point Purpose Making the Adjacent Channel Power ACP MeasurementMaking the Adjacent Channel Power ACP Measurement Measurement Method Results ACP Setup RecommendationMaking the Measurement Table Making the Adjacent Channel Power ACP Measurement Changing the Measurement SetupAdjacent Channel Power Measurement Defaults Figure 4-10ACP Measurement - Bar Graph View Maximum Making the Adjacent Channel Power ACP MeasurementMaking Measurements Chapter Offset A 750.000 kHz Offset B 1.98000 MHz Chapter Changing the View •Limit Test - Turns off the limit test function Making Measurements Making the Adjacent Channel Power ACP MeasurementFigure 4-11ACP Measurement - Spectrum View Chapter Troubleshooting Hints This adjacent channel power ratio measurement can reveal degraded or defective parts in the transmitter section of the UUT. The following examples are those areas to be checked further Purpose Making the Channel Power MeasurementMaking the Channel Power Measurement Measurement Method Results Channel Power MeasurementMaking the Measurement Figure Channel Power Measurement Defaults Changing the Measurement SetupTable Page Troubleshooting Hints Using the MarkerChanging the Display Purpose Making the Power Stat CCDF MeasurementMeasurement Method Results Power Statistics CCDF MeasurementMaking the Measurement Figure Power Statistics CCDF Measurement Defaults Changing the Measurement SetupTable Changing the Display Making the Power Stat CCDF MeasurementChanging the View Making Measurements Troubleshooting Hints Using the Markers•Off - Allows you to turn off the selected marker Service Measurements Front Panel Test on page Pwr vs Time on page Purpose Test SetupTimebase Frequency Measurement Method Window One Time Record Window Three Freq ErrorResults Window Two Magnitude Purpose 50 MHz AmplitudeTest Setup Measurement Method Window One RF Magnitude Window Three ErrorResults Window Two Cal Magnitude Purpose SensorsTest Setup Measurement Method Making Measurements Sensors Chapter Test Setup Front Panel TestPurpose Making Measurements Front Panel Test Troubleshooting HintsResults Chapter Purpose Service Power vs. Time MeasurementService Power vs. Time Measurement Making Measurements Using Baseband I/Q Inputs Option B7C What are Baseband I/Q Inputs? What are Baseband I/Q Signals? Why Make Measurements at Baseband? Making Measurements with Baseband I/Q Inputs Making Measurements Baseband I/Q Measurement OverviewUsing Baseband I/Q Inputs Option B7C Chapter Selecting Input Probes for Baseband Measurements Making Measurements Using Baseband I/Q Inputs Option B7CChapter Table Agilent Probes - Balanced and Unbalanced Selecting Baseband I/Q Input Connectors Selecting Baseband I/Q Inputs •IF Align - Select to view the IF alignment signal. This signal is available as a diagnostic function, to check the operation of the alignment signal in the case of alignment failure. Once selected, a menu accessing the IF alignment signal parameters is available at the bottom of the Input menu. Either CW, comb, or pulse signals may be selected. Because the alignment signal is input at the IF frequency, it is displayed on any active Spectrum Freq Domain window, regardless of center frequency I/Q Range Settings by Displayed Unit of Measure Setting Up Baseband I/Q InputsTable I and Q TableI and Q Offset Increment vs. I/Q Range I/Q Range Making Measurements Using Baseband I/Q Inputs Option B7CChapter Selecting Baseband I/Q Input Impedance Baseband I/Q Measurement Views Spectrum Views and 0 Hz Center Frequency Waveform Views for Baseband I/Q Inputs RF vs. Baseband I/Q Input Measurement Views, by Comparing RF and Baseband I/Q Measurement ViewsTable Measurement Baseband I/Q Measurement Result Examples Channel Power Measurement Making Measurements Using Baseband I/Q Inputs Option B7CSpectrum Frequency Domain Measurement Chapter Figure 4-19Basic Mode Spectrum Linear View- Baseband I/Q Inputs Waveform Time Domain Measurement Baseband I/Q Key Access Locations Baseband I/Q Key Access LocationsTable Table Baseband I/Q Key Access LocationsUsing Baseband I/Q Inputs Option B7C Making Measurements Baseband I/Q - Spectrum I/Q Marker Query BbIQ Programming CommandsCALCulate Subsystem Baseband I/Q - Waveform I/Q Marker Query Sets the amplitude reference level for the y-axis Baseband I/Q - IQ Offset CalibrationDISPlay Subsystem Spectrum - Y-AxisScale/Div Spectrum - Y-AxisReference Level Baseband I/Q - Select Input Impedance Reference INPut SubsystemBaseband I/Q - Select Input Impedance Baseband I/Q - Activate IQ Alignment MEASure Subsystem Baseband I/Q - Select I/Q Power Range SENSe Subsystem Select the Input SignalBaseband I/Q - Select I/Q Voltage Range 5 If You Have a Problem Instrument Messages and Functional Tests document Problem Symptoms and Solutions Key or Feature Does Not Appear in Menu If You Have a Problem LAN External Loopback Test Failed - Error MessageInstrument Fails Alignment - Error Message Problem Symptoms and Solutions LAN Communication Problem Instrument Power-OnProblemInstrument Keyboard is Locked Agilent Technologies Test and Measurement Support, Services, and AssistanceChapter Table 5-1Contacting Agilent Returning Your Instrument to Agilent TechnologiesAsia Call Center Numbers Options and Accessories Option BAC: cdmaOne Measurement Personality Options and Measurement PersonalitiesOption BAH: GSM Measurement Personality Option BAE: NADC/PDC Measurement Personalities Option BAF W-CDMAMeasurement Personality Option HN1: iDEN Measurement PersonalityOption B78: cdma2000 Measurement Personality Option B7C: Baseband IQ Measurement Personality Option 202: EDGE with GSM Measurement Personality Option 300: 321.4 MHz IF Output Option 0B1: Additional Copy of Manuals Option 1CM Rack Mount Kit Option 0BV: Component-levelService DocumentationOption 0BW: Assembly-levelService Documentation Option 1CN Handles Kit AC Probe AccessoriesBroadband Preamplifiers and Power Amplifiers GPIB Cable Model Number N2714A Calibration and Adjustment SoftwareRS-232Cables Description Index IndexNumerics Index Index Index Indexoff, 140 select, 140 shape, 140 trace, state IndexIndex Index Index