Agilent Technologies E9300 manual Measurement Considerations, Accuracy

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	Measurement Accuracy and Speed
	Configure the power meter as follows:

Note	The example shows the key labels for a single channel power meter.
	Dual channel meters are similar, adding channel identification to the
	softkey labels.

System

1. Press Inputs , Input Settings . The current setting is displayed under the Range softkey.

2.To change this press Range . A pop up window appears. Use or

to highlight your choice.

To confirm your choice press Enter .

The section “Setting the Range, Resolution and Accuracy” in the Agilent EPM series power meters Programming Guide shows you how to configure these parameters using the remote interface

Measurement Considerations

While autoranging is a good starting point, it is not ideal for all measurements. Signal conditions such as crest factor or duty cycle may cause the power meter to select a range which is not the optimum configuration for your specific measurement needs. Signals with average power levels close to the range switch point require you to consider your needs for measurement accuracy and speed. For example, using an Agilent E9300/1/4A sensor, where the range switch point is -10 ± 0.5 dBm in a pulsed signal configured as follows:

Characteristic	Value
Peak Amplitude	-6 dBm
Duty Cycle	25 %

the calculated average power is -12 dBm.

Accuracy

The value of -12 dBm lies in the lower range of the Agilent E-series E9300 power sensor. In autoranging mode (“AUTO”) the Agilent EPM series power meter determines the average power level is below -10 dBm and selects the low power path. However, the peak amplitude of -6 dBm is beyond the specified, square law response range of the low power path diodes.The high

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Contents Operating and Service Guide Copyright 1999 Agilent Technologies Certification WarrantyLegal Information Exclusive Remedies Limitation of WarrantySound Emission General Safety InformationConventions SafetyPower Meter Front Panel Operation Related Publications DocumentationSensors Covered by Manual Documentation Table of Contents Standing Wave Ratio SWR and Reflection Coefficient Rho Per Introduction Typical HP E-series E9300 power sensors General Information Power Meter RequirementsSimplified Block Diagram of Diode Pair/Attenuator/Diode Pair Agilent E-Series E9300 Power Sensors in DetailGeneral Information Initial Inspection Checking Power Meter Firmware and DSP RevisionGetting Started Interconnections and Calibration Specifications Making Measurements What You’ll Find This Chapter Auto-averaging Settings Power Meter Configuration ChangesSpread Spectrum Signal Measuring Spread Spectrum and Multitone SignalsCdma IS-95A 9Ch Fwd Cdma Signal Measurements90 % Frequency GHz Typical Lower Range Calibration Factor Multitone Signal MeasurementsAchieving Stable Results with Tdma Signals Measuring Tdma SignalsPower Meter and Sensor Operation Input Settings , More Achieving Stable Results with GSM SignalsElectromagnetic Compatibility EMC Measurements Measurement Accuracy and Speed Setting the RangeAccuracy Measurement ConsiderationsSummary Speed and AveragingSpecifications and Characteristics Introduction Sensor Low Power Path High Power PathMaximum SWR E9300/1/4/A Power Sensor SpecificationsConnector Type 0C to +55C Maximum DC Voltage Maximum Power± 2.5% Power LinearityTypical Power Linearity at 25C, after zero Additional Power Zero Set Zero Drift Measurement Noise Switching PointTime E4418B E4419B Settling TimeCalibration Factor and Reflection Coefficient X2 ModeCal Factor Uncertainty General Frequency Range E9300/1B and H Power Sensor SpecificationsE9300B Typical SWR 25C ± 10C E9300H Typical SWR 10 MHz to 18 GHz 25C ± 10C Maximum Power Sensor To 35 C To 55 C GHz E9300/1B To 0 dBm To 10 dBm 10 to 20 dBm 20 to 26 dBm For larger changes refer to the following table E9300/1H DBm to 0 dBm +44 +30 dBm E9300/1B Conditions Zero Set Zero Drift2 Measurement Settling Time Typical Cal Factor Uncertainty Low Power Path Cal Factor Uncertainty High Power Path Storage and Shipment Environment ReferencesE9300/1B and H Power Sensor Specifications Service Connector Cleaning CleaningFrequency System Rho Actual Maximum Uncertainty Measurement Performance TestPerformance Test Is the illustrated parts breakdown IPB that identifies all Replaceable PartsIllustrated Parts Break down Reference Agilent Part Qty Description Designation Number LABEL, ID E9301B Principles of Operation ServiceRepair of Defective Sensor TroubleshootingDisassembly Procedure Removing Power Sensor Shell Reassembly ProcedureAsia Pacific Sales and Service OfficesEurope