Research On Beamforming Oriented IEEE 802.11n

With the addition of MIMO to IEEE 802.1 ln, multiple antennas enable beamforming emerge, The beamforming applies the weights, which are adapted from knowledge of the propagation environment or channel state information, to the transmitted signal to improve system performance.This paper mainly researchs on Beamforming oriented IEEE 802.1 ln, based on the characteristics of the 802.1 ln channel models. Two different beamforming technologies, MIMO beamforming and array antenna beamforming, have their respective advantages in different conditions. Conclusions are acquired by simulation as follows:Firstly, in the NLOS environment, By weighting the transmitted signal, the MIMO beamforming technologies obtains spatial diversity and multiplexing gains, and improves channel performance. Secondly, when the antenna distance between the sender and receiver is less than the break-point distance, which will give rise to a line-of-sight component,and the transmitting array antennas appear co-located, applying the adaptive array antenna's Eigen-beamforming in 802.1 ln channel model, the array gain will be obtained. Finally, in the existence of LOS and the several separate sub-array antennas, using a second-order cascade configuration to joint MIMO and array antenna beamforming, the adaptive beamforming will provide much higher system performance than the conventional MIMO or array antennas respectively.