Directional distributed co-ordination function - a medium access control protocol to simultaneously support both omni-directional and smart antennas in a same WLAN cell
نویسندگان
چکیده
Directional distributed co-ordination function (D-DCF), a modified medium access control protocol of IEEE 802.11, is proposed to support hybrid antennas such as smart adaptive array antennas and normal omni-directional antennas, in one wireless local area network cell. Nodes equipped with smart antennas follow D-DCF and nodes equipped with normal antennas follow DCF. D-DCF based on a hybrid virtual carrier sense mechanism maintains compatibility with DCF. In D-DCF, before sending any data-frames, the sender and receiver node transmit a pilot sequence by means of an omni-directional request-to-send/clear-to-send handshake mechanism. Based on the pilot, the directional beam can be formed by the smart antenna. Then the node can transmit its data-frame in the directional mode. The other nodes save the transmission time between the sender and receiver in the omni-directional mode in their network allocation vectors. When the sender and receiver communicate in the directional mode, the other nodes can access the channel to send their data-frames. Hence, D-DCF supports space division multiplexing. Moreover, D-DCF fully supports time division duplex, namely both the forward and backward transmission in one access period. Simulation results show that D-DCF can support the hybrid antenna system effectively and provide much higher network throughput, lower delay, jitter and packet-loss-rate than DCF does.
منابع مشابه
Evaluation of a BIBD Based Directional MAC Protocol for Wireless Ad Hoc Networks
The use of directional antennas in wireless ad hoc networks can significantly improve global performance due to a high spatial channel reuse. Nevertheless, its introduction poses new location dependent problems related to the MAC protocol. In this paper, the Balanced Incomplete Block Design theory has been exploited to develop a new MAC protocol for wireless ad hoc networks using directional ant...
متن کاملAn RSSI-Based Cross Layer Protocol for Directional Ad Hoc Networks and Its Implementation
Smart antenna (or directional antenna) technology has been developed recently, which can control its antenna beam pattern to a specified direction by software. Medium access control (MAC) protocols using smart antennas, called directional MAC protocols, have the following potentials: higher spatial reuse, larger extension of communication range, less interference and higher total throughput com...
متن کاملA Directional MAC Protocol with Deafness Avoidance in Ad Hoc Networks
This paper addresses the issue of deafness in MAC (Medium Access Control) protocols for wireless ad hoc networks using directional antennas. Directional antennas are expected to provide significant improvements over omni-directional antennas in ad hoc networks, such as high spatial reuse and range extension. Recently, several MAC protocols using directional antennas, typically referred to as di...
متن کاملUniversity of California Santa Cruz Medium Access Control in Ad Hoc Networks with Omni-directional and Directional Antennas
Medium Access Control in Ad Hoc Networks with Omni-directional and Directional Antennas
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- IET Communications
دوره 1 شماره
صفحات -
تاریخ انتشار 2007