The present application relates to a method for operating a cellular multiple input and multiple output system comprising a first device (20) having at least two antenna arrays (22, 23) and second device having at least two antennas (32, 33). According to the method, a same uplink pilot signal is broadcasted from each antenna (32, 33) of the second device (30) and the same uplink pilot signal is received at each antenna array (22, 23) of the first device (20). At the first device (20), first device transmission parameters are determined for each antenna array (22, 23) depending on the received same uplink pilot signal. Downlink pilot signals are sent via antenna array (22, 23) using the determined first device transmission parameters and the downlink pilot signals are received at each antenna (32, 33) of the second device (30). This second device determines second device receiving parameters for each antenna (32, 33) depending on the received downlink pilot signals.