最近這幾年無線網路大量的被使用在日常生活上，而使用者的位置隱私也受到了很大的威脅。在現有的無線區域網路的環境中，攻擊者會透過使用者不會改變的網路卡實體位置來追蹤使用者。到目前為止有許多相關的研究是為了解決這個問題而提出來的，但由於這些相關的研究並沒有將附近的移動裝置之移動行為列入考慮，所以這些研究的解決方法會錯失許多可以改善使用者隱私的時機，也就是說現有的方法在交換網路卡實體位址的時機並不一定是最好的；而且可能會造成許多不必要的交換網路卡實體位址，導致網路的效能降低。因此，在本篇論文中，我們以相對定位的方法為基礎來提高使用者的位置隱私；並分析使用者附近移動裝置的移動行為來決定哪些移動裝置需要交換其網路卡實體位置。而經由實驗結果得知，我們的方法與現有的方法比較雖然會稍微減低網路流量，但確實能減低其網路卡實體位置的交換次數，也提高了使用者的位置隱私。

Recently wireless network massive is used in the daily life, but user's location privacy can be threatened. In wireless local area network (WLAN), an adversary can track a user through his/her unchanged MAC address. Many correlation researches have been proposed to combat this issue, but they have not included mobile behavior of neighboring nodes in the consideration, therefore these research solutions may miss the opportune moment to update MAC address to improve the user’s location privacy. In other words, the existing scheme in the opportune moment to update MAC address may not be the best one. Furthermore, they will have many unnecessary MAC address to update, causes the network throughput be reduced. In this thesis, we will be able to enhance user's location privacy with the relative-positioning scheme. We will analyzing the mobile behavior of neighboring nodes to decide which mobile will need to update their MAC address. The experiment results show that our scheme can decrease the time of MAC address to change, and also to enhance user's location privacy. Although the network throughput will be a little lower.

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