大型天然災害會癱瘓通訊系統，嚴重影響到救災效率，本論文旨在快速進行可用的鄰台間無線電鏈結頻寬分配，供應急通訊系統使用。無線通訊技術的成熟，為使用者帶來極大的便利性，但當發生大規模的地震或強烈颱風等重大天然災害時，通訊系統卻常常因架構等因素，隨著電力與交通系統的損毀而癱瘓。由歷年大型災變中多數災區內之行動通訊系統全面中斷即可印證行動通訊系統其實是極為脆弱，而有效運作的通訊系統卻是災情傳遞、資源調度以及互助協調是否順利的關鍵因素。 本文所探討的應急通訊系統是利用倖存的連通基地台和斷訊卻沒有損毀的基地台，以無線電連接起來建構一個臨時性的通訊系統，稱為應急蜂巢式行動通訊網路(Contingency Cellular Network，CCN)。由於CCN鄰台間無線電鏈結的頻寬有限，大量話務將造成通訊系統壅塞，影響重要訊息傳遞，且災區各個地方需求與受災情況不盡相同，使得CCN頻寬資源需視各地需求與需求緊急程度進行規劃配置，以充分發揮頻寬效益傳遞重要資訊。本論文主要在探討如何在CCN網路拓樸、連外頻寬分配已決定的情況下，進行CCN跨基地台頻寬分配，以達到最大的救災效益。我們提出一適合CCN樹狀結構的頻寬分配優化模型，在兼顧涵蓋率的情況下追求救災效益的最大化，此模型可供使用者(救災指揮單位)系統化的解決CCN跨基地台頻寬分配問題。 本文所提出的頻寬分配模型包含CCN樹狀拓樸、鄰台間之無線電鏈結頻 寬資源限制、需求對(存在通訊需求之兩基地台)、差異化之通訊品質通道和頻寬效益遞減函數。我們證明此模型是NP-Hard問題，並提出一個考慮各需求對緊急程度以及通訊品質需求差異而進行快速頻寬分配的演算法，此演算法以貪婪法在各中間步驟挑選當下效益密度最高的選擇賦予頻寬，如此逐步計算得到最終解。 我們以電腦模擬的方式，評估CBBAG演算法搭配不同頻寬救災效益密度計算之效能。在我們的實驗中，CBBAG演算法搭配additive的頻寬救災效益密度計算方式所的效能最佳，在小規模模擬環境下，在所模擬的30個亂數產生的案例中，CBBAG演算法與最佳解相較，效能差距不超過9.4%。而在大規模環境下，在所模擬的10個亂數產生的案例中，CBBAG演算法與準最佳解相較，效能至少超過最少21.8%，最多43.26%。 最後我們以unit cost of coverage improvement比較兩種效益遞減函數在增加涵蓋率時所承擔的效益成本。由實驗結果可以發現，CBBAG演算法搭配1/sqrt(分配至某需求對的頻道數)效益遞減函數所付出的效益成本較小。

在大型天然災害發生之後的黃金救援時期，災民存活率和救災效益之提昇極度仰賴於一個順暢的通訊系統。由歷年來大型災變的經驗中我們可知，行動通訊系統其實是不可靠且極為脆弱的，基地台之電力供應中斷或連接後端固定網路線路（Backhaul）之損毀都將使得通訊系統癱瘓而影響救災工作效率。 本研究提出一種新的應急通訊系統，利用原有行動通訊系統中未損毀但失去連網能力的基地台，藉由臨時供應的電力恢復其運轉，並以無線通訊設備與鄰近基地台互連建構一個臨時應急性的網路，稱為應急蜂巢式行動通訊網路（Contingency Cellular Network，CCN），供災區內手機用戶進行通訊。由於災區內部通訊的對象通常是一個特定的群組角色，而非一個特定人員，而災民與救災人員也不知彼此所在位置及聯絡的方式，因此無法以平常的撥號方式發起呼叫。本研究以CCN網路架構為基礎，設計並實作群組通訊模式，讓災區內人員以簡碼方式向任一群組發起呼叫並建立通話。 為驗證CCN群組通訊設計之可行性及效能，我們以IEEE802.11 Wi-Fi無線網路環境建置模擬系統，並以Android平台手機搭配VoIP軟體模擬手機與系統連線以進行通話。最後設計了一連串的實驗評估本模擬系統之效能。從實驗結果可知，本系統可於短時間內即時回應使用者註冊需求及完成通話連線處理；當通話數在30通以下時，Mouth-to-Ear Delay (MED) 值可維持在400ms以下，語音品質控制在一般VoIP使用者可容許的範圍之內。本實驗可作為未來改進系統功能和建置架構之參考依據。 / When stricken by a catastrophic natural disaster, the efficiency of disaster response operation is very critical to life saving. The efficiency of disaster response operation is greatly depending on communication systems. However, they were usually not dependable, including cellular networks, and often crashed due to power outage and backhaul link breakage. The failure of communication systems caused a big coordination problem to many disaster response operations. This thesis proposes a Contingency Cellular Network (CCN) by connecting isolated base stations to survival base stations using long-range wireless links to restore part of cellular network functionality. People can use their own cell phones for emergency communication in the disaster areas. CCN will be able to support many disaster response workers in the early hours of catastrophic natural disasters, thus to save many lives. Since the receiver of a phone call in a disaster area is usually a resource (agent), not a particular person, we designed a special Agency communication mode for CCN allowing CCN users to initiate a phone call to a nearby resource by dialing a designated agency number, instead of a real phone number. To verify our design, we implemented an emulated CCN system using an IEEE 802.11 Wireless LAN to mimic the CCN network and Android small phones with VoIP software to mimic user terminals. Finally, we conducted a series of experiments to evaluate the performance of the emulated system. The experimental results show that the emulated system can respond promptly to the user registration and call set-up requests. Mouth-to-Ear Delay (MED) can be effectively controlled below 400 ms when there is no more than 30 calls originated. This system may be used as reference for the future development of contingency communication networks.

當發生大規模的地震或強烈的颱風等重大天然災害時，通訊系統常常隨著電力與交通系統的損毀而癱瘓。由歷年大型災變中多數災區內之行動通訊系統全面中斷即可印證行動通訊系統其實是極為脆弱的，然而有效運作的通訊系統卻是災情傳遞、資源調度及救災是否順利的關鍵因素。本文所探討的應急通訊系統利用倖存的連通基地台和斷訊卻沒有損毀的基地台，以無線電連接起來建構一個臨時性的通訊系統，稱為應急蜂巢式行動通訊網路(Contingency Cellular Network，CCN)。由於各地災情狀況不完全相同，CCN的建構順序必須考慮災區的輕重緩急、時間的急迫等因素依序建構。因此當CCN拓樸規劃完成後，根據CCN拓樸、各地災情嚴重程度以及拓樸中基地台間的相對距離(運輸時間)進行基地台建構排程規劃，以達到最大的總救災效益。 本文考慮各基地台所能發揮的救災效益、所需建構時間、以及運輸工具從任一基地台到另一基地台所需運輸時間，提出兩個適合CCN拓樸樹狀結構的考慮資源運輸路徑之最佳化排程模型CCNDS-AC和CCNDS-UC。CCNDS-AC限制建構順序必須從連網台往下循序建構，但CCN-UC則否。因發生突發性大型天然災害時，可容許的計算時間相當短暫，因此提出了兩個快速的啟發式演算法DS-ACG與DS-UCB，可在短時間內求出一組相當逼近於最佳解的建構排程順序，與DS-UCB相互比較。本文以電腦模擬的方式進行小規模實驗與大規模實驗評估，並且用Genetic Algorithm來比較啟發式演算法的效能。結果顯示DS-UCB明顯優於DS-ACG及Genetic Algorithm。在小規模實驗中DS-UCB可求得與最佳解的總救災效益誤差平均約0.9%的近似最佳解建構順序。而在大規模實驗下， DS-UCB與十萬個解中的最佳解─pseudo optimal solution相較，總救災效益平均高出約16.7%，而總救災時間平均約少了19.4%。 / When stricken by a large-scale disaster, the efficiency of disaster response operation is very critical to life saving. However, cellular networks were usually crashed in earthquake, typhoons or other natural disasters due to power outage or backhaul breakage. Unfortunately, the efficiency of communication system is a critical factor to the success of disaster response operation. We designed a contingency cellular network (CCN) by connecting physically intact but service-disrupted base stations together with wireless links. Since the transportation capacity may be very limited, scheduling of CCN deployment order according to the demand of disaster operation and traveling time between base stations becomes an important issue. We propose two optimization models: CCN Deployment Scheduling Antecessor Constrained Problem (CCNDS-AC) and CCN Deployment Scheduling Unconstrained Problem (CCNDS-UC), aiming to maximize the efficiency of disaster response operation. Both problems are proven to be NP Hard. We also designed two rapid heuristic algorithms, DS-ASG and DS-UCB to solve the problems respectively when it is needed in urgent. Finally, we evaluated the proposed algorithms against optimal solutions (in small cases only) as well as genetic algorithm by simulation. The experimental results show that DS-UCB outperforms all other algorithms. In small scale cases, the profit obtained by DS-UCB is only 0.9% smaller than what the optimum solution can get. In large scale cases, as compared to the pseudo optimum solution, which is the best solution among 100,000 solutions, DS-UCB outperforms pseudo optimum solutions in profit by 16.7%, and in traveling time by 19.4%, both in average.

歷年發生的大型天然災害中，行動通訊系統常常會因為道路、橋樑、電力的損毀而導致嚴重癱瘓，進而影響災後救援工作的進行，行動通訊系統其實是不可靠且極為脆弱的。為使災區能夠快速地恢復通訊，本研究提出一種應急通訊系統，利用無線通訊，將這些無連線能力的基地台連接起來，並利用存活可連至核心通訊網路的基地台，建構成為一個臨時性的通訊系統，稱為應急蜂巢式行動通訊網路(Contingency Cellular Network，CCN)，供使用者在災區內進行通訊。由於資料庫的可靠度在行動通訊網路中具有舉足輕重之地位，本論文旨在利用分散式架構提高CCN網路資料庫的可靠度，進而提高系統可靠度。我們先分析資料表的特性，並依據各資料表的特性以及資源之多寡，設計相應的分散式架構。 我們利用樹狀拓樸的簡單特性，提出三種分散式架構：(1)用於群組資料表的階層備援式架構、(2)用於HLR資料表的階層備援式架構，以及(3)用於HLR資料表的鄰近階層備援式架構。這三種架構都利用了樹狀拓樸的簡單特性，大幅簡化了資料庫的查詢及更新程序。我們以可用度及平均總成本，以評估各架構在不同的情形下之最合適架構，並觀察在各架構下，其系統可用度與平均總成本之間的關係，由結果可知，在群組資料表儲存架構中，若追求高系統可用度，可選擇高儲存密度之架構，反之，若追求較低的成本，可選擇低儲存密度之架構。而在HLR資料表儲存架構中，階層備援式的系統可用度與平均總成本比鄰近階層備援式來得高，表示階層備援式耗費較多成本，但可用度也較高，故在建置時可依實際情況來選擇合適的架構儲存。 最後，為驗證分散式資料庫架構之可行性，我們利用數部筆記型電腦及Android平台手機來建置階層備援式及鄰近階層備援式架構，並測量在此二種架構下於通話建立時所耗費的時間，從模擬結果可知，此二種架構皆可快速建置並可立即通訊，惟鄰近階層備援式所耗費的通話建立時間略長，但仍在可容許範圍之內。 / When stricken by a catastrophic natural disaster, the efficiency of disaster response operation is very critical to life saving. The efficiency of disaster response operation is greatly depending on communication systems. However, they were usually not dependable, including cellular networks, and often crashed due to power outage and backhaul link breakage. The failure of communication systems caused a big coordination problem to many disaster response operations. This thesis proposes a Contingency Cellular Network (CCN) by connecting isolated base stations to survival base stations using long-range wireless links to recover part of cellular network functionality. People can use their own cell phones for emergency communication in the disaster areas. CCN will be able to support a large number of disaster responders with limited resources in the early hours of disasters, thus to save many lives. Because the reliability of database plays a very important role in the CCN, this thesis proposes a distributed database architecture to improve the reliability of database so as the reliability of CCN. We take advantage of the simplicity of CCN tree topology to design three distributed database architectures: (1) Hierarchical Redundancy Architecture for “Group_Member ” table, (2) Hierarchical Redundancy Architecture for “HLR” table, and (3) Hierarchical Neighboring Redundancy Architecture for “HLR” table. The tree topology greatly simplified the query and update procedures. We use availability and average total cost to analytically evaluate all three architectures trying to identify the most appropriate architecture under different circumstances. Based on our evaluation results, CCN operators can choose the most appropriate architecture according to their realistic circumstances. Finally, in order to verify the feasibility of the proposed architectures, we implemented a simplified prototype using several laptops and Android mobile phones. The Hierarchical Redundancy Architecture and the Neighboring Redundancy Architecture were implemented. The results show that both architectures can be functional with reasonable performance except that Hierarchical Neighboring Redundancy Architecture may take longer time, but in a tolerable range, to setup a call.

當發生大規模地震或強烈颱風等大型天然災害，其災後72小時為人命搜救之黃金期。由歷來的大型災變中，可知行動通訊系統其實極為脆弱且不可靠，而通訊系統癱瘓將影響救災工作之成效。本論文中探討的應急通訊系統利用倖存之連通基地台和斷訊卻沒有損毀的基地台，以無線電互相連接成一個轉送拓樸以建構臨時性通訊系統，稱為應急蜂巢式行動通訊網路(Contingency Cellular Network，CCN)。 在災難發生後，災區通常有許多須要較高通話需求的關鍵區域，其通話需求遠高於輕度災區，建置CCN時必須優先保障其通訊需求，我們先前之研究所提出的樹狀轉送拓樸其結構較脆弱，若任何一個link斷訊失去轉送功能，則其節點以下的使用者通訊將受到影響，導致任何一個節點對外通訊能力非常脆弱，影響CCN之可用度。為了提升CCN之可用度，我們提出了多路徑的CCN網路拓樸解決方案，在本方案中，每個關鍵區域都有數條對外通訊的連線。 本論文以各基地台通訊範圍內的通訊需求人數與災區毀損程度，作為效益參數，在有限緊急修復資源下，將問題塑模為一個類似K-Maximum Spanning Tree問題的Length Bounded Disjoint K-Path Max-Profit Mesh問題，我們證明它屬於NP-Hard問題，並且提出快速且效能不差之啟發式演算法，可在緊急時建立應急蜂巢式行動網路的多路徑網路拓樸。本文以電腦模擬方式，進行實驗以驗證我們的模型之適切性，並評估多路徑拓樸可提升之CCN可用度，實驗結果可提供使用者依不同的CCN可用度及總救災效益需求，選擇所需之多路徑數量。 / When stricken by a catastrophic natural disaster, the golden 72 hours is very critical to life saving. However, communication systems including cellular networks often crashed due to various causes making big impact to the efficiency of disaster response. Our research proposes the Contingency Cellular Network (CCN) by connecting disconnected base stations together using wireless links to form an overlay Ad Hoc network over a disconnected cellular network. 　　In our previous study, we proposed a tree topology to construct CCN, which is vulnerable since a single link failure may have a big impact to the availability of CCN. This thesis proposes a multi-path topology to enhance the availability of CCN such that the selected critical areas will have redundant communication paths connecting to the core network and thus, have higher resiliency against link failure. We model the CCN Multi-path Network Topology Design problem into a combinatorial problem, called Length Bounded Disjoint K-Path Max-Profit Mesh Problem. We take the degree of emergency and the population of each stricken area as the priority measure as well as the amount of emergency recovery resources as the capacity constraint in the topology computation model. The problem is proven to be NP Hard. Therefore, we designed an efficient heuristic algorithm (HLBDK) to solve the problem when it is needed in urgent. Finally, we evaluated the proposed algorithm by simulation. The simulation results show that the average performance deviation of the proposed heuristic algorithm away from the optimal solutions is smaller than 7% in all cases. A significant improvement in the availability can be obtained by using multi-path topology at a reasonable performance degradation. Our research results provide users a fundamental base to determine their availability requirement at a countable performance degradation.

大型天然災害會癱瘓通訊系統，嚴重影響到救災效率，本論文旨在快速進行可用連外頻寬分配，供應急通訊系統使用。無線通訊技術的成熟，為使用者帶來極大的便利性，但當發生大規模的地震或強烈颱風等重大天然災害時，通訊系統卻常常因架構等因素，隨著電力與交通系統的損毀而癱瘓。由歷年大型災變中多數災區內之行動通訊系統全面中斷即可印證行動通訊系統其實是極為脆弱，而有效運作的通訊系統卻是災情傳遞、資源調度以及互助協調是否順利的關鍵因素。 本篇論文所探討的應急通訊系統是利用倖存的連通基地台和斷訊卻沒有損毀的基地台，以無線電連接起來建構一個臨時性的通訊系統，稱為應急蜂巢式行動通訊網路(Contingency Cellular Network，CCN)。由於CCN的連外頻寬有限，大量話務將造成通訊系統壅塞，影響重要訊息傳遞，且災區各個地方受災情況不盡相同，使得 CCN 的頻寬資源需視各地災情緊急程度與需求進行規劃配置，以充分發揮頻寬效益傳遞重要資訊。本論文主要在探討如何在CCN網路拓樸已決定的情況下進行頻寬分配，以達到最大的救災效益。因此我們提出一適合 CCN 樹狀結構的頻寬分配優化模型，以追求救災效益的最大化，這個模型可供使用者(救災指揮單位)系統化的解決 CCN 頻寬分配問題。 本論文所提出的頻寬分配模型包含 CCN 樹狀拓樸、基地台數目、可用之連外頻寬資源限制、各基地台Backhaul頻寬限制、基本頻寬需求限制、差異化之通訊品質通道和效益遞減函數。我們證明此模型是NP-Hard問題，並提出一個考慮各基地台的災情緊急程度以及通訊品質需求差異而進行快速頻寬分配的演算法，此演算法透過計算頻寬分配總救災效益決定優劣。經實驗，可快速得出接近最佳解的頻寬分配結果。 / When stricken by a large-scale disaster, the efficiency of disaster response operation is very critical to life saving. We propose to build a contingency cellular network to support emergency communication in large scale natural disasters by connecting disconnected base stations. This thesis addresses the bandwidth allocation problem. The advance of mobile communication technologies has brought great convenience to users. Cellular phone becomes the first communication tool most people would use in emergency. However, cellular networks were usually crashed in earthquake, typhoons or other natural disasters due to power outage or backhaul breakage. Unfortunately, the efficiency of communication system is a critical factor to the success of disaster response operation such as resource allocation as well as coordination of rescue and relief operations. We designed a contingency cellular network (CCN) by connecting physically intact but service-disrupted base stations together with wireless links. As the bandwidth resource in CCN is limited, a smart bandwidth allocation to facilitate prioritized bandwidth sharing will maximize the contribution of CCN to the disaster response operation. We model the CCN Bandwidth Allocation Problem into a Nested 0-1 Knapsack Problem aiming to maximize disaster operation efficiency. The problem is proven to be NP Hard. We also design an efficient heuristic algorithm to solve the problem when it is needed in urgent.