Powerline communication is based on differential signal, which means the sender sends two signals via two wires and the receiver will judge whether it is 0 or 1 by comparing these two signals. This is why HomeplugAV can only achieve SISO communication as it alreadyuses two wires to send data.For the same reason, HomeplugAV2 can achieve 3*3 MIMO communication at most via live wire & neutral wire, live wire & ground wire and neutral wire & ground wire.
With MIMO technology, TL-PA8010P & TL-PA8030P can have 2 MIMO streams.