This paper deals with a multi-user downlink MIMO-OFDM scheme with perfect channel knowledge at both the transmit and receive sides. The objective is to optimize the average BER while fulfilling each user's rate and satisfying a global transmit power constraint. Space division multiple access (SDMA) is investigated and three new iterative schemes are proposed to compute the linear pre-decoders. The results exhibit, inter alia, that orthogonalizing the channels does not lead to the best results.
['Jonathan Duplicy', 'Jérôme Louveaux', 'Luc Vandendorpe']
Optimization of linear pre-decoders for multi-user closed-loop MIMO-OFDM