Modified Cooperative Access with Relay’s Data (MCARD) based Directional Antenna for multi-rate WLANs

In this paper, for multi-rate wireless local area networks (WLANs), a modified protocol in Medium Access Control (MAC), called Modified Cooperative Access with Relay’s Data (MCARD) based Directional Antenna using half wave length dipole in Uniform Circular Array (UCA) topology is proposed. MCARD gives remote stations chance to send their information by using intermediate stations (relays) to Access Point (AP) at a higher data rate based practical antenna. As can be seen under MCARD, a relay station transmits its information before forwarding information from the source station because it uses directional antenna. Analytical results and simulations show that MCARD can significantly improve system quality of service (QOS) in terms of throughput under different channel conditions.