近年來，許多Range-Free定位技術利用具位置資訊的移動式感測器，幫助無位置資訊的固定式感測器獲得位置資訊，這類技術主要可分為 Area-Based 與 Point-Based 兩大類。雖然這兩類技術均可有效的賦予感測器位置資訊，然而，其中卻依然存在一些問題。在Area-Based 定位技術中，其並無針對移動式感測器該如何行走、該在哪些地點發送訊號，才可有效的提高移動式感測器定位效率進行探討，導致移動式感測器無法有效率的使用其有限的電量。此外，Area-Based 定位技術亦可能由於定位精準度不高，導致感測器間無法區別相對位置，進而影響現存需相對位置資訊之技術的效能，如具位置知覺之繞徑協定。另一方面，Point-Based 定位技術沒有將固定式感測器定位的時間納入考量，導致所有固定式感測器完成定位的時間是不可預期的。有鑑於此，本論文提出三種不同的定位技術，分別為Anchor-Guiding (AG) Scheme、Differentiating Relative Location (DRL) Scheme 與 Rapid Localization (RL) Scheme，用以改善現存 Area-Based 及 Point-Based 技術的效能。首先，本論文所提出之 AG 技術屬於Area-Based定位技術，其可幫助移動式感測器規劃移動路線及發送訊號的地點，進而提昇固定式感測器的位置精準度，並讓移動式感測器的移動方式更有效率。接著，本論文所提出之DRL技術為另一個Area-Based定位技術，其可幫助固定式感測器區別其與鄰居的相對位置，用以提高現存需位置資訊之技術的效能。最後，本論文所提出之 RL 技術屬於Point-Based技術，其將固定式感測器的定位時間納入考量，大幅減少固定式感測器定位所需的時間，進一步改善現存 Point-Based 定位技術的效能。實驗結果顯示，本論文所提出的三個定位技術，可有效的解決現存 Area-Based 及 Point-Based 技術所產生的問題，大幅提昇感測器定位的效能。 Recently, many range-free localization approaches employed a location-aware mobile anchor to help sensors acquire their location information. These approaches can be mainly classified into two categories: area-based localization approaches and point-based localization approaches. Although both area-based and point-based approaches can provide location information for sensors, however, some problems still exist. The area-based approaches did not discuss how the mobile anchor moves and where the beacons should be broadcasted. That is, the mobile anchor might consume a lot of energy in broadcasting unavailable beacons that cannot help sensors acquire accurate location information. In addition, since the area-based approaches only offered sensors rough location information, sensors might not distinguish relative locations with each of their neighbors, leading to a poor performance for some applications such as the location-aware routing. On the other hand, the point-based approaches did not take into account the time required for each sensor to complete localization process. Thereby, the time required for all sensors to exactly acquire their locations is unpredictable. This thesis proposes three localization schemes, including Anchor-Guiding (AG) scheme, Differentiating Relative Location (DRL) scheme, and Rapid Localization (RL) scheme. The AG scheme is developed for the mobile anchor to construct an efficient movement path and determine beacon locations, while the DRL scheme aims to help sensors distinguish relative locations with each of their neighbors. Finally, the RL scheme reduces the time required for each sensor to determine its location. Theoretical analyses and performance evaluations show that the three proposed schemes can significantly improve the performance of existing localization techniques.
