隨著科技進步，近年來無線資料流量每年都在持續增加，為了提供大量增加的資料流量和對各種應用的頻譜需求，公民寬頻無線電服務 (Citizens Broadband Radio Service, CBRS) 是一種解決方法。本論文根據代理人 (Domain Proxy) 實現在自我組織網路(self-organized networking, SON)服務器中的架構，利用SON的特性，使Domain Proxy能夠更有效的管理許多公民寬頻無線電服務設備(Citizens Broadband Radio Service Device, CBSD) ，並且代理CBSD向(Spectrum Access System, SAS)進行頻譜要求。此外，Domain Proxy也會擁有並管理一段CBRS頻譜的分配，並將管理的CBRS頻譜分配給其服務的CBSD。Domain Proxy必須針對不同優先權用戶頻譜使用權，進行分配。若在一次頻譜分配後，因為可能會有比某一個既有的CBSD還要更高優先權的CBRS用戶要使用頻譜，所以原本在使用此channel的CBSD需要將這個channel讓出來供高優先權CBRS用戶使用，這樣會造成原本某CBSD正在使用的channel不能夠再繼續使用，必須要重新向SAS索取新的channel的使用授權，藉著移動到其他channel進行頻譜使用。因此，在等待授權的期間這個被移動的CBSD少了CBRS channel，就無法讓連接到其的民眾使用良好的服務品質。
為了讓正在使用3.5 GHz頻譜的用戶能夠一直使用被分配到的通道 (channel)，且同時滿足CBRS對於不同優先權用戶頻譜使用權與通訊傳輸干擾的要求，我們提出了最小化傳輸不連續性演算法 (Minimize Discontinuity of Transmission Algorithm, MDTA)，在滿足CBRS用戶的優先權、先服務較早來的CBSD和一般許可接取使用者 (Generalized Authorized Access, GAA)受到其他同channel的GAA的必須干擾小於一個域值的條件下，來達到最小化CBSD被移動到其他channel的次數。MDTA考慮以上所敘述的三個條件，會先分配頻譜給先來的優先接取使用者 (Priority Access License, PAL)，再分配給較晚來的PAL用戶，接著分配給先來的GAA用戶，最後分配給較晚來的GAA用戶。MDTA同時也考慮GAA受到其他同channel的GAA的干擾小於一個域值，讓GAA可以有效的使用頻譜資源。模擬結果顯示我們的方法減少了CBSD被移動到其他channel的次數，我們的方法比其他人的方法減少96~98%移動次數。

With the advancement of technology, wireless data traffic has continued to increase yearly. To provide a large amount of increased data traffic and spectrum requirements for various applications, Citizens Broadband Radio Service (CBRS) is a feasible solution. This thesis considers the architecture that Domain Proxy is implemented in the self-organized networking (SON) server and uses the characteristic of SON which enables Domain Proxy to manage many Citizens Broadband Radio Service Devices (CBSDs) more effectively. Domain Proxy can assist CBSDs to request the spectrum from Spectrum Access System (SAS). It will also own the SAS granted spectrum and manage the granted spectrum allocation to its served CBSD. Domain Proxy allocates the spectrum based on the priority of CBSDs. After a spectrum allocation, a higher priority CBRS user may want to use the spectrum, so the higher priority CBRS user will take the channel used by a lower priority CBSD. This will cause the channel originally used by a lower priority CBSD cannot continue to be used by that lower priority CBSD. This lower priority CBSD has to request a new channel from SAS to get another channel for further spectrum access. Therefore, without the CBRS channel, this low priority CBSD cannot provide good quality of service for its served mobile users while it is waiting for authorization.
To allow CBSDs continuously use the granted CBRS channel, we propose the Minimize Discontinuity of Transmission Algorithm (MDTA), aiming to minimize the number of times that CBSDs moved to other channels by three conditions which are the priority of CBRS users, the earlier joining time of CBSDs, and the GAA's interference caused by other GAAs. MDTA considers the priority of CBRS users first. Then, MDTA serves the earlier jointed CBSDs. MDTA will firstly allocate spectrum to the first-coming PALs, and then to the later PALs. Further, MDTA will allocate spectrum to the first-coming GAAs, and finally to the later GAAs. MDTA also considers that GAA's interference from other GAAs on the same channel needs to be less than a threshold, so that GAA can effectively use CBRS spectrum. The simulation results show that the proposed MDTA reduces the number of times CBSDs are moved to other channels. Specifically, the proposed MDTA reduces the number of moves by 96~98% compared with other methods.

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