A low-power antenna selective synchronization method for IEEE 802.11ac WLAN systems

Abstract

This paper proposes an antenna selective timing synchronization method for multiple-input multiple-output orthogonal frequency division multiplexing-based IEEE 802.11ac wireless local area network systems. IEEE 802.11ac systems support up to eight antenna elements for adopting an MIMO technique. The increase in the number of antennas results in high power consumption due to the very high computational complexity involved. In addition, cyclic delay diversity applied for each antenna causes timing synchronization difficulties due to the pseudo-multipath problems. In order to solve these problems, a method to reduce the computational complexity of the synchronization is proposed by utilizing selective antennas with higher received signal power. The timing synchronization method with the adaptive accumulation window is also proposed to enhance synchronization performance. The simulation and power estimation results show that the proposed timing synchronization method not only improves the performance, but also reduces the computation power considerably. The proposed method is very useful for IEEE 802.11ac wireless LAN systems, where not only synchronization performance but also computation power is one of the most important issues.