Wireless Mesh Networks (WMNs) consist of mesh clients and mesh routers, where laptops, cell phones and sensor nodes are mesh clients, while mesh routers with minimal mobility are used for data forwarding. In this paper we focus on the improvement of wireless mesh network performance using smart antenna, and in particular, switched beam directional antennas. We have used STDMA(Spatial Time Division Multiple Access) medium access control (MAC) protocol, where links are preassigned time-slots according to a schedule in such way that interference is avoided allowing dense reuse of time slots within the network. An antenna uses different patterns depending on the direction towards a communication need to be established. Switching from one radiation pattern to other radiation pattern consume energy and take some time to stabilize new radiation pattern. We have analyzed the methods that are used to schedule the time-slots and minimize the number of switchings for communication.