Hi , Ad-hoc networks are basically dynamic networks formed on demand by a group of nodes without any pre-existing network infrastructure. Self-configurability and easy deployment feature of the Mobile Ad-hoc network (MANET) resulted in numerous applications in modern era. An efficient and effective medium access control (MAC) protocol is essential in ad-hoc network for proper sharing of channel. The Omnidirectional antenna has been used in traditional MAC protocols. Many studies show the advantages of using Directional MAC with respect to Omnidirectional. However, some of these studies also highlight the possible drawbacks that occur when a Directional approach is used. Good luck and best regards

http://www.fang.ece.ufl.edu/mypaper/winet09wang.pdf

hi

there are many study get research in this field.