hello to all
i have a question about markers on a E4406A
in basic mode ( spectrumanalyzer mode) 10Mhz span / resolution auto / eg i input a unmodulated signal on 100.0000Mhz from a signalgenerator.
i put the CF on 100.0000 Mhz , then marker and search , then the marker is spot on 100.0000Mhz
but if i put the CF on 103.000Mhz and then again marker and search then the marker is not spot on 100.0000Mhz but eg 100.03567Mhz
the same goes for CF eg 98.0000 Mhz and then again marker is not spot on the 100.0000Mhz
can someone explain to me what i am doing wrong or is this a the fact it is not a real spectrumanalyzer.
all alignment test are succesfull.
regards ,
andre
i have a question about markers on a E4406A
in basic mode ( spectrumanalyzer mode) 10Mhz span / resolution auto / eg i input a unmodulated signal on 100.0000Mhz from a signalgenerator.
i put the CF on 100.0000 Mhz , then marker and search , then the marker is spot on 100.0000Mhz
but if i put the CF on 103.000Mhz and then again marker and search then the marker is not spot on 100.0000Mhz but eg 100.03567Mhz
the same goes for CF eg 98.0000 Mhz and then again marker is not spot on the 100.0000Mhz
can someone explain to me what i am doing wrong or is this a the fact it is not a real spectrumanalyzer.
all alignment test are succesfull.
regards ,
andre
It is possible for the resolution bandwidth chosen that the peak value is shared among three trace points (the center frequency and +/- 35 kHz). You are correct that the E4406A is not a spectrum analyzer. It uses FFTs to represent the spectrum trace. Also, the spectrum measurement is limited. The E4406A core value proposition was its wireless measurement applications and one-button standards compliant measurements. It works well for GSM, EDGE, cdmaOne, 1xEV-DO, cdma2000, iDEN, NADC, PDC, and other standards for measuring EVM and code-domain power. E4406A also interfaced with the 89601A VSA software as a flexible vector signal analyzer. You can still use E4406A as a general purpose vector signal analyzer by interfacing with it via MATLAB or any other programming language to read out the waveform I/Q data and to post process this whatever programming environment you like. You could even save the I/Q data as .MAT format and open it in the newer 89601B VSA software. Here are the SCPI commands you’d use to grab waveform complex I/Q data out of the E4406A’s Basic waveform measurement:
Example to get I/Q data out of the narrow band digitizer in E4406A and PSA E4440A (note: I turned on time corrections)
:INST:SEL BASIC // Set the analyzer in Basic mode
:FREQ:CENTER xxxMHz // Set center frequency
:FORM REAL,32 // Set the returned data type to REAL, 32
:FORM:BORD SWAP // Set the Byte order to Swap
:INIT:CONT 0 // Set analyzer to single sweep
:WAV:BWID:RES 300kHz // Set RBW
:WAV:BAND:TYPE FLAT // Set filter to Flattop
:CAL:TCOR ON // Turn time corrections on
:POW:RF:ATT xx // Set attenuation
:WAV:SWE:TIME xxx // Set sweep time
:WAV:ACQ:PACK xx // Set data packing if necessary (Only needed for
RBWs between 1.2 and 7.5 MHz where you need
more dynamic range, although this may not be
recommended)
:READ:WAV0? // Returns the I/Q data
Now, save your I/Q data in a .MAT file and open it in 89601B software, or use MATLAB to perform an FFT to display the data or use MATAB to perform any kind of post processing that you like.
Regards -