I don’t know about the efficiency of it but I get a better signal on the tracking generator.
Yes something will have to be done to cut down the input signal from the outging device. Gain settings will likely not be enough.
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I replaced a misbehaving cable and did some further experimenting. I found that changing the decimation improved a lot of things. Flatness of response improved as did rejection of spurs. Signal distortion was reduced. The filters seem to have sharper response too. But the bandwidth gets narrowed. I have clean repeating of a 1KHz tone with 20KHz deviation at -95dBw. Gain is about 40db. Band 13 is only 10MHz wide. I don’t know how this INI will work with some of the really wide bands, even with adjusting.
I tested my Band13 ini for receiving. It took my phone from 3G 1bar to 4G 2bars but did not connect. I think it could see the base so it gave me a readout but could not get a response back so it gave up and fell back to 3G. The FFT viewer showed me a low level signal that would distort with feedback if I tried to turn the gain up.
This is about what I expected. I think it may work. Next I will feed the UL Tx into a SpecAn and monitor it while the phone is trying connect and see if it sends a clean signal. I wish I could see a waterfall of the Tx channels in real time.
Nice one - you got a result! I use a second cheapo SDR running on another PC to monitor base station Tx with waterfall.
Here’s my Arduino controlled LimeSDR Rig ready to do some serious work:
Needs a few more flashing LEDs I think?
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Nice. I am using the plastic standoffs still because I don’t like the proximity of some components to the holes.
I want voltage controlled amplifiers for the external gain stages. I see you have some nice sliders for that. Remind us of the link to that backplane. I know it’s in discourse somewhere.
It says it is for pick and place but it was designed to be used for two different purposes so it works for LymeSDR are as well.