PSA Measurement Setup Parameters
This topic provides measurement and parameter setup information that is unique to PSA spectrum analyzers with 89600 VSA. This information will help to properly setup the 89600 VSA and make measurements for the various PSA with 89600 VSA measurement systems.
If your PSA has option 266 (ESA/PSA Series Programming Code Compatibility Suite) make sure the Remote Language for the PSA is set to SCPI. To see if your PSA has option 266, press the following keys on your PSA:
or send the SCPI command . To set the Remote Language to SCPI, press the following keys on your PSA: and select SCPI or send the SCPI command .Measurement Setup Parameters for the PSA with 89600 VSA
Periodic Trigger (PSA opt 122 or opt 140 only) |
|
Fast Average (PSA opt 122 or opt 140 only) |
|
Custom Channel Configurations | Trig Out |
Alignment/Calibration: Selecting Calibrate from the Calibration dialog box ( ) will initiate a PSA full alignment.
Note that the 89600 does not detect warm-up status for the PSA, so the WARMUP calibration status message will never appear for PSA measurement hardware.
Channel Setup: 2 PSAs can be used without option 122 (80 MHz Megahertz: A unit of frequency equal to one million hertz or cycles per second. bandwidth) or option 140 (40 MHz bandwidth) to do dual-channel measurements. (See PSAs Setup as Dual ADCs.) Only a single RF Radio Frequency: A generic term for radio-based technologies, operating between the Low Frequency range (30k Hz) and the Extra High Frequency range (300 GHz). channel is available for a PSA with option 122 or option 140.
Custom Channel Configurations: The Custom Channel Configurations dialog ) is used to create custom channel mapping configurations, that is, you can reconfigure the hardware input channel to VSA measurement channel connections. The VSA only allows valid channel configuration mappings; "invalid" channel configuration mappings are disallowed (indicated by a red "X") and the "OK" button is disabled "greyed out".
Custom Channel Configurations
The Custom Channel Configurations dialog is used to create custom channel mapping configurations, that is, you can reconfigure the hardware input channel to VSA measurement channel connections. When using the Input Channel Configuration dialog to specify or modify the input channel configuration mapping, only the VSA default set of channel configuration mappings are allowed; "invalid" channel configuration mappings are disallowed and the " " button is disabled "greyed out".
Coupling: For RF measurements, the following coupling restriction applies:
- For E4446, E4447, and E4448 analyzers, only DC coupling is available.
The external reference frequency can be set from 1 MHz to 40 MHz, although specifications do not apply above 30 MHz. The default is 10 MHz.
Fast Average: PSA opt 122 (80 MHz bandwidth) or opt 140 (40 MHz bandwidth) only. If Fast Average is specified and triggering is set to Periodic Trigger, the averaging is performed in the PSA hardware which is faster than averaging performed in the 89600 software.
Hardware averaging only applies if the number of measurement frequency points is less than 6401 for span > 19.53 MHz or 102401 for span < 19.53 MHz and the Fast Average Update Rate is less than 52.4288.
Frequency: the PSA model determines the frequency limits as listed in the following table where:
- Center Freq Range is the range of frequencies the center frequency can be set to.
- Display Blanking shows the frequencies that are blanked on the display (outside the Center Freq Range).
Model |
Center Freq Range |
Display Blanking |
---|---|---|
E4440A |
1 kHz kiloHertz: A radio frequency measurement (one kilohertz = one thousand cycles per second). to 26.5 GHz Gigahertz: A frequency measurement which equals one billion hertz. |
<1 kHz and >26.5 GHz |
E4443A |
1 kHz to 6.3 GHz |
<1 kHz and >7.2 GHz |
E4445A |
1 kHz to 13.2 GHz |
<1 kHz and >13.7 GHz |
E4446A |
1 kHz to 44 GHz |
<1 kHz and > 44 GHz |
E4447A |
1 kHz to 43.5 GHz |
<1 kHz and > 43.5 GHz |
E4448A |
1 kHz to 50 GHz |
<1 kHz and > 50 GHz |
Front Panel PSA Control The Disconnect feature can be used to pause the 89600 and release its control of the PSA. Then the PSA can be used independent of the 89600. When returning to the 89600 and starting or resuming a measurement, the 89600 restores the PSA state that was set before disconnected.
The 89600 uses only the PSA Basic MODE. Because the PSA keeps track of the state information for each mode separately, the front panel setup will not be lost when alternating between 89600 software control and PSA front panel control. To return the PSA to front panel control with the previous state, simply click Disconnect in the 89600 Control menu, then select the appropriate non-Basic mode from the PSA front panel. Press the restart key in the 89600 software to return to 89600 software control of the PSA.
Hardware: PSA is listed as a Logical Instrument in an Analyzer Configuration. See PSAs Setup as Dual ADCs) for setup of 2 PSAs.
Mixer Level: The 89600 VSA Mixer Level control adjusts the Input Attenuation and ADC Analog-to-Digital Converter Range of the PSA. The default Mixer Level setting set by the 89600 VSA software is represented as O dB. AnyMixer Levelsetting selected is relative to the default Mixer Level setting.
For more information on Mixer Level control, see Mixer Level.
Overlap: The PSA does not support overlap processing, however overlap processing is available during recording playback.
Periodic Trigger: PSA opt 122 (80 MHz bandwidth) or opt 140 (40 MHz bandwidth) only. Periodic triggering specifies that triggering will occur at regularly spaced intervals and is useful when the input signal is periodic. Except for the first trigger point, all subsequent trigger points are determined by counting samples of the input signal.
The reference oscillators of the periodic source and the PSA must be locked.
When Periodic Trigger is selected (Input > Trigger > Trigger tab), the following parameters must also be set:
- Period specifies the trigger interval.
Set it equal to an integer multiple of the input signal period.
Default: 10 ms - Sync Source setting determines how the
first measurement is triggered.
- Free Run: (default) The measurement uses periodic triggering in a free-running state, ignoring any external triggers.
- Ext Trig: When an external trigger is present, the Period timer is moved to synchronize with the external trigger. When an external trigger is not present, periodic triggering occurs in a free-running state.
- Sync Delay is used when Sync
Source is set to Ext Trig. The value entered determines where the first trigger occurs relative to the external
trigger signal. When Sync Source is set to Free Run, Delay is disabled.
Default: 0 s
The Period must be set precisely so that the triggering is accurate. For example, assume the input signal repeats at a 30 kHz rate and period equal 3.33333…. usec. The Period parameter accepts a double precision value, so set the period value to 33.3333333333333 usec. This will enable the trigger position to be stable enough for thousands of averages to be performed.
Preset Setup: The following table lists the PSA specific preset setup configuration parameter settings. To preset the analyzer, select . To view a complete list of the standard set of preset setup parameters and values, see the Preset Setup topic. (Any parameters not listed here are set to the standard Preset Setup values.)
Parameter |
Default setting |
---|---|
Range |
|
Frequency |
depends on model |
Bands |
10 MHz to PSA max freq |
Center |
1 GHz |
Span |
8 MHz (80 MHz with opt 122, 40 MHz with opt 140) |
Time Data Zoom/Baseband |
Zoom |
ResBW |
100 kHz |
Time |
depends on model |
Main Time Length |
38.28125 mSec |
Max Overlap |
90 % |
Gate on/off |
Off |
Length |
1.66015625 mSec |
Range: Select a range by choosing a Full Scale Range in the 89600 VSA. The RF input maximum and minimum limits are listed in the following table and can be adjusted in 2 dB step size increments. The VSA then sets the optimal attenuator, ADC gain, and optimal preamp on/off setting for the PSA in order to optimize dynamic range primarily for noise and secondarily for intermodulation distortion. The PSA options included in the following table are:
- Option 1DS (100 kHz to 3 GHz built-in preamplifier)
- Option 110 (100 kHz to 26.5 GHz or 100 kHz to 50 GHz built-in preamplifier)
- Option 122 (80 MHz bandwidth)
- Option 140 (40 MHz bandwidth)
PSA model |
Opt 122 or 140 |
Min (dBm) |
Max (dBm) |
Step |
Freq Range |
---|---|---|---|---|---|
With option 1DS |
no |
-60 |
30 |
2 dB |
below 3 GHz |
With option 110 |
no |
-60 |
30 |
2 dB |
All |
Without option 1DS or 110 |
no |
-30 |
30 |
2 dB |
All |
With option 1DS |
yes |
-58 |
30 |
2 dB |
below 3 GHz |
With option 110 |
yes |
-58 |
30 |
2 dB |
All |
Without option 1DS or 110 |
yes |
-28 |
30 |
2 dB |
All |
Recording: The VSA records time data from the PSA hardware to your PC's disk drive. The length of time waveform recording is limited to the time waveform length limit of the PSA.
For option 122 (80 MHz bandwidth) or option 140 (40 MHz bandwidth), the recording length is approximately 128 Msamples for spans > 19.53 MHz and approximately 64 Msamples for spans < 19.53 MHz.
Setup Save/Recall: The PSA state is not saved when the 89600 software is closed. When a setup is recalled into 89600, the PSA state is set appropriately based on the recalled 89600 setup.
Span: For the RF input, the span setting is limited to <10 Hz min and 8 MHz max (opt 122: 38 Hz min to 80 MHz max; opt 140: 38 Hz min to 40 MHz max). Span resolution is independent from PSA and unchanged from 89640 operation.
The VSA software uses a sample rate of 1.28 * the span to avoid the alias region in a majority of hardware platforms supported by the software. The wideband PSA has a different hardware architecture and samples at a rate of 1.2 * the span (when at full span). Since the VSA algorithms are based on this sample rate (1.28 * the span), the data will be resampled from 100 Ms/Sec to 102.4 Ms/Sec.
Trigger Holdoff: For PSAs without option 122 (80 MHz bandwidth digitizer) or option 140 (40 MHz bandwidth digitizer), trigger holdoff specifies the length of time after a trigger before the next trigger can occur. With option 122 or option 140, trigger holdoff specifies an amount of time that the analyzer's input signal must be a stable low value before the next trigger can occur.
To see if your PSA has option 122 or option 140, press the following keys on your PSA:
Triggering: The following trigger parameters are available:
- Style: Free Run, IF Mag (Video), External Periodic (see Periodic Trigger)
- Slope: available for IF Mag (Video), External
- Level: available for IF Mag (Video), External (for External, the level range is -5 to +5 volts)
- Holdoff Style: Conventional or Below Level
- Holdoff: available for IF Mag (Video), External
- Delay: available for IF Mag (Video), External ( the range for trigger delay is the lesser of the maximum waveform length for the PSA or -100 ms to +500 ms)
Trigger Type |
Level |
Level limits |
Default |
---|---|---|---|
IF Mag |
IF Level |
noise floor to 10 V |
0.01 V |
External |
Level |
-5 to +5 V |
2V |
For external triggering, specify the front or rear connector by clicking Input > Extensions > External Trigger Location. From the drop-down menu, select the appropriate connector.
Trig Out
Not all PSA options and bandwidths support the 89600 VSA Trig Out feature.
Refer to the Measurements book "Trig Out" topic's Unsupported Hardware table for more information.