A MIMO wireless transceiver includes: antennas, components forming transmit and receive chains coupled to the antennas, a signal combiner, and a predistortion calibration circuit. The transmit chain components include: pre-distorter circuits and power amplifiers (PA)s, The pre-distorter circuits each couple to a transmit chain for pre-distorting an associated signal thereon. The PAs are input coupled to a corresponding transmit chain and output coupled to a corresponding antenna. The signal combiner combines the amplified signals from all of the PAs into a combined output signal. The predistortion calibration circuit includes: a chain isolator circuit to isolate a selected amplified signal of a PA within the combined output signal from the signal combiner and an inverter circuit to determine from the selected amplified signal a mathematical inverse of the associated PA's non-linearity; and to provide corresponding pre-distortion parameters to the corresponding pre-distorter circuit,