A new propagation model for collision detection using MIMO transmission in wireless LAN systems

We have proposed a method which realizes collision detection by utilizing 2-by-2 multi-input multi-output (MIMO) transmission in wireless LAN systems. We assume the collision due to multiple short preamble signals. In the proposed method, We utilize a fact that the short preamble signal is transmitted from only first antenna. Then, an access point (AP) can detect interference signals by using a second antenna. Moreover, to reduce mutual coupling between first and second antennas, the use of orthogonal polarized antennas is proposed. In this paper, we propose a new propagation model for a quantitative evaluation on the proposed collision detection. Moreover, the accuracy which detects the interference power is evaluated by using the proposed propagation model.