物聯網(IoT ; Internet of Things)的發展是未來網路的新趨勢，各界都在積極尋求物聯網走向的契機下，未來將會有更多裝置以及物件連接網路，帶來全方位的影響。無線感測網路(wireless sensor network ; WSN)由多個具備通訊功能而且能偵測環境資訊裝置所構成，可用於發展物聯網感知層，而裝置數量隨著網路的範圍擴大，將提高傳輸時的碰撞機率，並大幅降低網路的產能與效能。
IEEE 802.15.4標準為了時間急迫性的應用以及滿足固定頻寬需求定義了免競爭週期，超碼框在分配免競爭週期的保證時槽時，如果未考慮資料大小，將造成頻寬破碎問題。裝置在競爭週期中，使用CSMA/CA機制進行資料傳輸，其中的後退演算法卻無法視網路的情形自行動態改變，且對於不同型態的資料或是不同裝置，皆視為同種類傳輸，無法提供保證服務品質。
此外，超碼框的訊標級數和超碼框級數，決定活動週期與非活動週期的長度。當訊標級數降低時，裝置可以傳輸的時間增加，雖然能使產能提升但也帶來了能源消耗；而訊標級數大於超碼框級數則可以延長網路壽命但會減少產能且增加傳輸延遲時間。
本論文提出以優先權為基礎的適應性超碼框及保證時槽配置演算法(PASAGA)，改進IEEE 802.15.4標準使不同的訊號與資料在傳輸的過程中降低延遲時間、提供保證服務品質；並配置切割後的保證時槽，提升整體的頻寬利用率；設計適應性的超碼框調整工作週期，降低網路系統的能源消耗。
模擬結果顯示PASAGA提升高優先權的有效產能以及降低高優先權的平均傳輸延遲時間，改善整體網路的能源效率，並且能經過調整參數以適應不同的環境要求。將來可以持續探討本論文的研究方向，為未來的無線感測網路研究提供參考。

Internet of Things (IoT) development is the trend of future network. All sectors are actively seeking the opportunity to the IoT. It will have more devices and objects connected to the network and bring a all-round influence in the future. Wireless sensor network (WSN) consists of a number of communication functions and can detect the environment information, these devices can be used to develop the IoT sensor layer. The number of devices with the scope of the network to expand, will increase the probability of transmission collision and significantly reduce the network capacity and performance.
IEEE 802.15.4 defines contention free period for the application of time urgency and the need to meet the fixed bandwidth requirements. If the packet size is not considered in the allocation of the guaranteed time slot, the bandwidth fragmentation problem will be caused. Devices use CSMA/CA mechanism for data transmission in the contention access period, which can not view the network according to the situation of self-regulation. And for different types of information or different devices are regarded as the same type of transmission, can not provide Quality of Services.
In addition, beacon order and superframe order determines the beacon interval and superframe duration. When superframe order is decreased, the time it takes for the device to be transmitted increases, but it also brings energy consumption. While beacon order is greater than superframe order, increasing the lifetime of the network but reducing thoughtput and transmission delay.
This thesis proposes the PASAGA (A Priority Based Algorithm for Adaptive Superframe Adjustment and GTS Allocation). Improve the IEEE 802.15.4 so that different signals and data in the transmission process to reduce the delay and provide Quality of Services. And allocate the new guaranteed time slot to enhance the overall bandwidth utilization. Then design the adaptive superframe to adjust the duty cycle and reduce the energy consumption of the network system.
The simulation results show that PASAGA improves the effective capacity of high priority, reduces the average transmission delay of high priority and improves the overall network energy efficiency. In addition, it can adjust the parameters to meet the different environmental requirements. In the future, we can continue to explore the research direction of this paper, and provide reference for future WSN research.

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