An apparatus for a multiple-input multiple-output (MIMO) architecture is disclosed. The apparatus includes a first splitter-combiner (S-C) having a first transmission line port, a first transmit (TX) port, and a first receive (RX) port. Also included is a first N-plexer having a first power amplifier (PA) input, a first RX output, and a first antenna output for coupling to a first antenna. A first PA is coupled between the first TX port and the PA input, wherein the first RX output is coupled to the first RX port.