Has anyone successfully transmitted different modulation schemes (e.g., AM on TX1 and FM on TX2) simultaneously using LimeSDR?
The LimeSDR has 2 Local Oscillators: 1 for receiving, 1 for transmitting.
As a result, you can easily receive at one frequency and transmit at a completely different frequency. But you cannot receive on channel 0 at one frequency and receive on channel 1 at a completely different frequency, same limitation for transmitting.
You can receive or transmit on 2 different frequencies if they are close enough, thanks to the NCO, but it seems the maximum difference is 80MHz, and it can depend on the sampling rate. Check Max NCO, relation to sampling rate, and NCO effect