It depends. An FPGA able to do that is a big one, quite expensive. Today, an even more so tomorrow, you can afford to do that kind of computations in a CPU and/

It depends. An FPGA able to do that is a big one, quite expensive. Today, an even more so tomorrow, you can afford to do that kind of computations in a CPU and/or a GPU. Regardless of who is doing the beamforming, the TX and RX analog parts are intrinsically quite expensive with at least dozen of channels.