Agilent Technologies E9300 manual Measuring Tdma Signals, Power Meter and Sensor Operation

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Measuring TDMA Signals

Measuring TDMA Signals

Power Meter and Sensor Operation

The voltages generated by the diode detectors in the power sensor can be very small. Gain and signal conditioning are required to allow accurate measurement. This is achieved using a 220 Hz (440 Hz in fast mode) square wave output from the power meter to drive a chopper-amplifier in the power sensor. Digital Signal Processing (DSP) of the generated square wave is used by the power meter to recover the power sensor output and accurately calculate the power level.

The chopper-amplifier technique provides noise immunity and allows large physical distances between power sensor and power meter (Agilent 11730 series cables available up to 61 metres). Additional averaging helps reduce noise susceptibility.

Achieving Stable Results with TDMA Signals

The averaging settings in the power meter are designed to reduce noise when measuring continuous wave (CW) signals. Initial measurement of a pulsed signal may appear unstable with jitter on the less significant displayed digits. With pulsed signals the averaging period must be increased to allow measurement over many cycles of the pulsed signal.

To set the averaging proceed as follows:

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


	1. Press	System		,	Input Settings	,		. Press the	Filter	softkey to
		System					More
		Inputs					More

access the filter menu.

2.The filter setting is displayed under the Length softkey label. To change this setting first set manual mode by pressing the Mode Man Auto softkey to highlight Man .

3.Press Length and use the , , or to set the averaging you require. Confirm your entry by pressing Enter .

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Contents Operating and Service Guide Copyright 1999 Agilent Technologies Legal Information WarrantyCertification Exclusive Remedies Limitation of WarrantySound Emission General Safety InformationPower Meter Front Panel Operation SafetyConventions Sensors Covered by Manual DocumentationRelated Publications 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 Getting Started Checking Power Meter Firmware and DSP RevisionInitial Inspection 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 MeasurementsPower Meter and Sensor Operation Measuring Tdma SignalsAchieving Stable Results with Tdma Signals 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 PathConnector Type E9300/1/4/A Power Sensor SpecificationsMaximum SWR 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 ServiceDisassembly Procedure TroubleshootingRepair of Defective Sensor Removing Power Sensor Shell Reassembly ProcedureAsia Pacific Sales and Service OfficesEurope