多跳分布式无线网络环境下自适应获取冲突避免的多址接入协议

该文为多跳移动的分布式无线网络提出了一种新型的媒质接入控制（MAC）协议，即公共－发送信道式自适应获取冲突避免（AACA－CT）协议，在该协议中，每个节点预先监测记录周邻节点的信道使用情况，从而自适应地为自己选择发送信道，并且利用在公共信道上发送的RTS分组唤起收方使用各自的发送信道而实现无冲突的通信，它的主要思想在于资源预约可以简便地利用半双工无线电台以异步方式灵活，有效地在多个频段，多个跳频（FH）码或多个直接序列扩频（DSSS）码上实现，而且不依赖于功能强大的基站或中心控制器以及有线骨干网的帮助，性能分析和仿真结果表明，它能有效地克服隐藏终端和暴露终端问题，并且可以完全解决侵入终端问题。

Multiple Access Protocol for Adaptive Acquisition Collision Avoidance in Multihop Wireless Ad Hoc Networks

This paper presents a new MAC protocol called adaptive acquisition collision avoidance multiple access protocol with common-transmitter-based channel assignment (AACA-CT) for multihop mobile wireless ad hoc networks to resolve the hidden terminal and exposed terminal problems effectively. Multiple channels are employed in this scheme. One channel is used as the common channel for mobile users (or nodes) contending to reserve traffic channels by means of request-to-send (RTS) packet. Other channels are used as traffic channels to transmit clear-to-send (CTS) and traffic packets without collisions. In the protocol, every node adaptively chooses an unused channel as its transmission channel in advance in multihop mobile environment and takes advantage of request-to-send (RTS) packet transmitted on a common channel to evoke its receiver to complete their communication process on their transmission channels without packet collisions. With this protocol, resource reservation is flexibly and effectively made on multiple frequency bands, frequency-hopping (FH) codes or direct-sequence spread-spectrum (DSSS) codes by half-duplex radios without any help of powerful base stations (BS) or central controllers and wired backbone networks in an asynchronous fashion. A comparison among proposed protocols, IEEE 802.11 MAC protocols and MACA-CT protocol, shows that the proposed reservation-based approach has advantages over other protocols.