Spectrum Analyzer

' Demonstration of basic Spectrum Analyzer measurement setup using COM.

set pna=CreateObject("AgilentVNA835x.Application","hostname")

set channel = Nothing

set sachannel = CreateSAMeasurement(pna)

SetupLinearSweep(sachannel)

ConfigureAdvancedSettings(sachannel)

' Create a Spectrum Analyzer measurement.

' Return the custom SA channel object.

Function CreateSAMeasurement(pna)

' Create a B measurement on channel 1

pna.Channels.RemoveChannelNumber(1)

call pna.CreateCustomMeasurementEx(1,"Spectrum Analyzer","B")

set channel = pna.Channels(1)

set sachannel = channel.CustomChannelConfiguration

set CreateSAMeasurement = sachannel

' Set frequency range

channel.centerFrequency = 3.0E9

channel.FrequencySpan = 2.0E9

' Center frequency step size

' Set to Auto mode with CenterFrequencyStepSizeMode = naMANUAL|naAUTO

channel.CenterFrequencyStepSize  = 20E6

' RBW filter shape

' Choices are:

'   0 - naNoWindow

'   1 - naWindowFlatTop

'   2 - naWindowGaussian

'   3 - naWindowBlackman

'   4 - naWindowKaiser

sachannel.BandwidthShape = 4 ' naWindowKaiser

' Detector type

' Choices are:

'   0 - naDTAverage

'   1 - naDTSample

'   2 - naDTPeak

'   3 - naDTNormal

'   4 - naDTNegPeak

'   5 - naDTPeakSample

'   6 - naDTPeakAverage

sachannel.DetectorFunction = 2 ' naDTPeak

' Video averaging type

' Choices are:

'   0 - naPower

'   1 - naLog

'   2 - naVoltage

'   3 - naVoltageMax

'   4 - naVoltageMin

sachannel.VideoAveragingType = 3 ' naVoltageMax

avgcount = sachannel.VideoAveragingCount

' ADC Filter

sachannel.ADCFilter = 38E6

' RBW and VBW values

sachannel.ResolutionBW = 100E3

sachannel.VideoBW = 10E3

' RBW/VBW and Span/RBW ratios

sachannel.ResolutionBWVideoBWRatio = 1.23

sachannel.SpanResolutionBWRatio = 134

End Function

' Configure a Spectrum Analyzer measurement for Linear sweep mode on Port 1.

Sub SetupLinearSweep(sa)

portnum = 1

portlabel = "Port " & CStr(portnum)

' Turn Port 1 ON

channel.SourcePortMode(portnum) = 1 ' naSourcePortOn

'  Set Port 1 sweep type to Linear

' Choices are:

'   0 - naLinearSweep

'   3 - naCWTimeSweep

sa.SourceSweepType(portlabel) = 0 ' naLinearSweep

' Set start and stop frequencies

sa.SourceStartFrequency(portlabel) = 2E9

sa.SourceStopFrequency(portlabel) = 4E9

' Set 'Source Number of Steps'. This is the number of frequencies to use between start and stop (inclusive).

' This setting is channel-wide.

sa.SourcePointCount = 5

' Set 'SA Sweeps per Source Steps'. This is the number of sweeps to take at each measurement frequency.

' This setting is also channel-wide.

sa.SourceRepeatCount = 2

End Sub

' Configure a few of the Advanced Settings for SA.

Sub ConfigureAdvancedSettings(sa)

' Set the 'Image Reject' selection.

' Choices are:

'   0 - naIRNoneHigh

'   1 - naIRNoneLow

'   2 - naIRMin

'   3 - naIRNormal

'   4 - naIBetter

'   5 - naIRMax

sa.ImageRejectMethod = 5 ' naIRMax

' Enable display of ImageReject traces.

sa.EnableImageRejectTraces = 1 ' naON

' Enable point mode.

' This forces the number of display points to match the FFT point count.

sa.EnableDetectorBypass = 1 ' naON

End Sub