MANET（mobile ad-hoc networks）屬於無線網路的一種運用，他的網路架構並沒有基地台的支援下，由一群可移動的節點所組成，網路中沒有專屬的路由器、伺服器、接取點與傳輸纜線。目前許多研究MANET網路都是架構在全向性天線與媒介層通訊協定下，但是由於全向性天線僅僅提供接收端與傳送端兩個節點之間的資料傳輸，其他節點必須等待，造成頻道的使用缺乏彈性，這將會限制網路總體的傳輸速率與影響運用的空間。
為改善MANET網路在全向性天線與媒介層通訊協定下所造成的缺乏，我們提出使用指向性天線的媒介層新協定稱為SWAP（Smart based Wider-range Access MAC Protocol）協定。指向性天線因為可以控制傳送角度，減少訊號干涉與節點碰撞的機會，達到擴大空間運用與資料傳輸的能力。SWAP協定是利用資訊交換技術得知鄰近節點的位置，並將本身座標的相對資訊提供給鄰近節點，我們計算鄰近節點的資訊與控制傳輸範圍的方式，達到增加傳輸能力與擴大空間。
SWAMP協定主要是運用全向性天線與指向性天線在傳送端與接收端不同的運用，達成擴大傳輸距離的目的。SWMP協定由兩種存取模式所組成，即是OM-mode和DM-mode，這兩種模式的選擇是取決於傳送端與接收端之間的相對位置。OM-mode在限定的區域內形成一個全方向性的NAV來改進空間的使用。在DM-mode中，一個高增益和指向性的天線被使用來延伸傳輸範圍。

MANET（mobile ad-hoc networks）is a network in the field of WLAN (wireless local area network). This is a network without infrastructure. It is constituted by a set of mobile nodes. Each mobile node functions as a host and router. Until now, most researches focus on MANET constituted by mobile nodes with omnidirectional antenna. With this kind of antenna, all the other nodes within the transmitting area must wait until sender finishing its work. Otherwise, a collision will be occurred. This will degrade the efficiency of bandwidth and decrease the throughput of the network.
To solve this problem, we propose a MAC protocol in MANET whose mobile nodes will use a directional antenna in addition to the omnidirectional antenna. This new protocol will be called as SWAP（Smart based Wider-range Access MAC Protocol）. With directional antenna, the angle of transmission area can be controlled and the probability of interference and collision within nodes can be decreased. With GPS and exchange of data, the coordinate of each node can be afforded to the neighboring nodes. Since each node knows the direction of its neighboring nodes, the antenna can be directed to the right direction and avoid unnecessary inference and collision.
There are two modes in SWAMP. With OM-mode, the usage of space can be improved by an omnidirectional NAV. With DM-mode, the distance of transmitted signal will be increased by a high gain and directional antenna. With the interactive usage of these two modes, the performance of MANET will be increased.

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