A system and a method to determine beam dynamics and multi-user performance of a base station having an antenna array including multiple antenna elements are disclosed. The system includes a measurement probe antenna positioned in a mid-field of the antenna array, a reference antenna having a fixed position with respect to the base station antenna array, and a coupling probe array including multiple coupling probe antennas positioned in a reactive field of the base station antenna array for coupling RF signals of the antenna elements to selected coupling probe antennas to form a high dimension radiation channel matrix between the antenna array and the coupling probe array. The system further includes a channel emulator configured to receive the measured antenna element patterns from the measurement probe antenna, to receive the RF signals coupled to the selected coupling probe antennas, to provide bi-directional channel models of channels between the base station and user devices.