車載無線網路中的IEEE802.11p標準中將頻率分為一個控制頻道(Control Channe)及六個服務頻道(Service Channel)共七個頻道供車輛使用，但現實環境裡對於頻道的需求量常常會超出實際所能提供的數量。因此如何妥善的分配這些有限的頻道是目前許多人研究的方向之一，並且VANET的環境變動性相當高，車輛的移動速度會造成連線上的困難，所以在分配頻道的同時也要考慮到環境的變動，本研究提出了使用叢集(Cluster)的概念來分配頻道，考量了車輛的相對速度及連線時間來形成叢集，讓叢集達到最小的變動，並且利用叢集頭(Cluster Head)去管理叢集成員(Cluster Member)，讓頻道的分配以叢集為單位去減少頻道的使用量，為了驗證，也與TaeOh Kim等人所提出的CMMP機制作比較，根據模擬結果，在Throughput及Collision Rate上皆有較好的表現。

The standard of 802.11p divides channels into one control channel and six service channels for vehicles in VANET environment; , but in the real world, however, the amount requirements of the needed channels are much more greater than currently available channels at most time in real world. How to allocate these channels appropriately is one of the important researches. Because the mobility of VANET is quite high, the speed of the vehicle often it makes causes difficulty ofin connection through the speed of the vehicle. It Thus, also considerations onsenvironmental changes of environment are equally essential when allocating channels. This paper proposed a cluster-based allocating channel scheme, considering relative speed of inter-vehicles and connecting time to form clusters so as to reach and let the minimumleast change of clusters. While Uusing cluster head to manage cluster members, cluster is used as a unit in channel allocation so that the usage load of channels can be decreasedand allocating channel based on numbers of the clusters. This paper is also compared with CMMP proposed by TaeOh for verification. According to the result of simulation results, it hasa better performance on throughput and collision rate was reached.

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