I’m not entirely sure what you’re asking here.

If you’re receiving then yes, it only needs one antenna. However — I leave a 50 ohm dummy load on the sending antenna because at least at one time the transmitter seemed always-on.

That’s all for the LimeSDR mini, which only has two antennas. The SDR (non-mini) is totally different and out of my domain.

For the mini, the most common problem is picking the wrong RF input (low vs high) which can effectively mute the radio.

Mark