SATSAGEN is a Windows application that allows you to use an SDR device as a Spectrum Analyzer. SATSAGEN supports the ADALM-PLUTO device only, at the moment.
SATSAGEN is provided free of charge to the HAM Radio community, with the hope that SATSAGEN can be appreciated as a useful tool for our radio experimentation.
Download SATSAGEN from this link:
The prerequisites of the application are:
- OS: From Windows 7 to Windows 10
- Drivers for ADALM-PLUTO installed: PlutoSDR-M2k-USB-Drivers
- ADALM-PLUTO device with firmware > = 0.31
WARNING: At the first start, the application will perform on the device the frequency and bandwidth extension needed for the use of the 70MHZ-6000MHZ range, forcing the firmware to “see” the AD9363 transceiver as an AD9364. The extension is required for the application to work, but if you don’t want it to happen, don’t start SATSAGEN.
I would like to thank my friends Gianni IW1EPY, Domenico I1BOC and Mauro IZ1OTT for giving me the idea, the support in every sense, the radio components and the equipment necessary for the realization of the project!
A special thanks goes to Boian Mitov for the GREATS libraries www.mitov.com used in SATSAGEN!
Below you will found another valuable contribution by Gianni and at the end of the post you will find a short video that illustrates the application basics.
“As Adalm Pluto owner I become acquainted to this device using radio programs (SDR Console, SDRAngel) to link Oscar 100.
But for this kind of hardware my asking was for a measurement system. I have test cheap network analyzer in the range of 4,4 GHz, vector analyzer up to 900 MHz and my idea was to set Pluto in this class of instruments using the extended range 70 MHz to 6 GHz.
After some encouraging trials from the RF point of view but disappointing for the measurement time delay in Matlab, I drag my friend Alberto into this adventure to have an acceptable measurement time using C libraries.
Apart the nice Alberto’s program I add some Hardware notes.
Adalm Pluto it is born for sure not for a professional measurement instruments so some drawbacks can be expected.
Due to the large bandwidth usage forced by the program (original Pluto frequency usage spans from 325 MHz to 3,8 GHz) the input and output impedance for sure are not 50 ohms.
A pair of attenuators on input and output mitigate the problem, for sure reducing the usable dynamic range but acceptable for HamRadio users. Using two 10 dB attenuators remain 40 dB down to the calibration level and 20 up in case of insertion of an active device under test.
The missing metal box generate some crosstalk problems in the upper range of frequency specially if Pluto is moved around metal frames or touched by fingers… some people have reboxed it.
The present structure (Pluto plus optional attenuators) allows a direct measurement of transfer function of filters, amplifiers, a directional coupler or a reflection bridge is mandatory for impedance measurement.
Is possible to attach a file to correct the deviation of output power over the frequency sweep, unluckily every Pluto have its own variance. By now I have analyzed 5 devices and the correction curve are available.
With the linearization file the output power can maintain an error of 1 dB versus 10 : 12 dB of the unleveled , most of this nonlinearity is located in the range from 50 to 300 MHz end 4.5 to 6 GHz obviously where Pluto was not designed for.
The receiver gain and the generator attenuator do not increase the linearization error, so one linearization file is enough. Pay attention to not overload the receiver or saturate the generator but this behavior become immediately evident.
To enhance the dynamic linearization is possible to apply a -40 dB calibration using a correct attenuator.
This linearization performs in the range thill -40 db but almost kill the response from -40 to -60, in any case due to cross talk end receiver erroring this range is severely degraded even without this correction.
All the level of the RX Gain and the Output Power and the attenuators that you have inserted at the I/O are programmable.
Any idea of improvement ?
This is the list of future enhancement:
Calibration using a directional coupler or bridge averaging open and short.
Offset between transmitter and receiver in order to test conversion systems.
Harmonic response of devices in order to test amplifiers or multipliers.
Open to suggestions.
I think that Adalm Pluto with SATSAGEN, covering 7 Ham bands, will be useful in designing and testing to every ones involved in RF field.