在本篇論文中，我們探討了數個無線人體區域網路(WBAN)存在同一地點的問題。此共存問題會造成同頻道間的干擾並且導致網路性能的下降。例如：電量的消耗或是封包碰撞。我們將頻道分配的問題轉化成著色問題去避免同頻道間的干擾。本篇論文的目標是提高同頻道間的再利用並且確保網路中有最多的WBAN被分配到頻道。我們提出了一個分散式的著色演算法，稱之為DTIC。DTIC使用了不完全著色的概念並考慮了兩步鄰居之間的相關頻道分配來達成我們的目標。除此之外，我們設計了一個傳輸協定，此協定能避免WBAN之間互相溝通時產生的封包碰撞。根據模擬結果顯示，與其他方法相比，我們的演算法在同頻道之間有較高的再利用。

In this thesis, we address the coexistence problem of Wireless Body area network (WBAN), which may cause severe co-channel interference and leads to performance degradation such as energy waste and packet collision. We formulate the channel allocation problem as a graph coloring problem to avoid the co-channel interference. Our main objective is to increase the co-channel reuse and allocate channels to as many WBANs as possible. We propose a distributed two-hop incomplete coloring (DTIC) algorithm based on game theoretic perspective to solve the graph coloring problem. The DTIC algorithm uses incomplete coloring and two-hop dependencies to accomplish our goal. In addition, we design a message passing protocol to avoid the packet collision when each WBAN communicates with each other. Simulation results show that our algorithm has better co-channel reuse than previous work.

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