Research On The Performance Of 802.11n Link Based On Directional Antenna Model

As the technology of MIMO-OFDM being introduced into wireless local access network (WLAN), the performance of WLAN improves so largely and revolutionarily. Generally speaking, the antenna model and array model is used with omnidirectional antenna model and uniform linear array (ULA) in the link simulation of wireless communication system. Based on next generation WLAN standard-802.11n, the paper mainly made research on the link performance, after added the directional antenna model and uniform circular array (UCA) model to the 802.11n link system, and validated it by making simulation.The paper presented three kinds of array structure of directional multi-beam smart antenna system, and the parameters of the unit antenna, and put forward three antenna pattern model. With regard to WLAN channel, the paper summarized the channel characteristics of the WLAN and the relevant concepts, and channel model used in 802.11n, and the relevant model to provide a theoretical basis of subsequent analysisAfter the analysis of antenna model and channel characteristics and model of WLAN, based on Geometrically Based Single Bounce (GBSB) model, the paper made research on the time of arrival (TOA) and directional of arrival (DOA) probability distribution with different antenna models, and shown the simulation results. Then, the paper studied the correlation performance of omnidirectional antenna and directional antenna models. Finally, the result indicated that the correlation coefficient of directional antenna model was a little larger.Making use of the link simulation platform of 802.11n, the paper simulated bit error rate (BER) performance with the different antenna models, type of polarization and type of antenna pattern. Meanwhile, analyzed anti-interference performance of directional antenna. The simulation results shown that, BER performance of UCA directional antenna model is slightly worse than that of ULA omni-directional antenna model. The BER performance of dipole antenna model is a little better than that of monopole antenna model. As the gain of directional antennas improves, the BER performance is getting better. The anti-interference performance of directional antenna is much better than omnidirectional antenna.