Hello together,
here is a small update on the status of my MSi001 Teensy convolution project.
After doing some additional shielding of the board and putting everything together in the metal box and as planned supplyng it from Li ion battery, I succeeded to drop the noise floor slightly lower than before (see the table below). But the main task was to check the actual dynamic range with current hardware (SGTL5000 - VDDA=3.3V claims SNR-90dB).
Basically used the algorithm proposed from Frank.
The settings are also included in the picture
The dynamic range that I succeeded to measure is roughly around 82dB, equivalent of around 14 bit resolution.
Second topic is more for fun
Last days I got a bit more time and I add some kind of "Menu Assistant"
Now it is possible with long press of the encoder to call the "Menu Assistant" and it is possible to scroll up and down, change the selected position and as well is indicated small block diagram to to give you hint what you change at the moment.
As an advantage it is possible to scroll with the encoder directly (much faster) and also 7 positions of the menu are visible at a time.
The actual code lies here:
https://www.dropbox.com/s/64i77appz8sz1lc/Teensy_Convolution_SDR_Msi001_v3_5_2020_07_24.rar?dl=0
here is a small update on the status of my MSi001 Teensy convolution project.
After doing some additional shielding of the board and putting everything together in the metal box and as planned supplyng it from Li ion battery, I succeeded to drop the noise floor slightly lower than before (see the table below). But the main task was to check the actual dynamic range with current hardware (SGTL5000 - VDDA=3.3V claims SNR-90dB).
Basically used the algorithm proposed from Frank.
......
Concerning the "bit resolution", I personally think it would be better to measure the "dynamic range" of the whole system:
* use 50 Ohm resistor instead of an antenna
* "measure" the noise level in 500Hz bandwidth
* insert a signal of defined (high) signal level into the antenna input
* measure the largest signal level without compression / desensibilization in 500Hz bandwidth
* and the difference between the two measurements is the dynamic range of the whole SDR system
* if you can achieve 16 bit == 96dB, your system will be high end quality, I think
.........
The settings are also included in the picture
The dynamic range that I succeeded to measure is roughly around 82dB, equivalent of around 14 bit resolution.
Second topic is more for fun
Last days I got a bit more time and I add some kind of "Menu Assistant"
Now it is possible with long press of the encoder to call the "Menu Assistant" and it is possible to scroll up and down, change the selected position and as well is indicated small block diagram to to give you hint what you change at the moment.
As an advantage it is possible to scroll with the encoder directly (much faster) and also 7 positions of the menu are visible at a time.
The actual code lies here:
https://www.dropbox.com/s/64i77appz8sz1lc/Teensy_Convolution_SDR_Msi001_v3_5_2020_07_24.rar?dl=0