台灣地區LTE-A系統之頻譜規劃與佈建方式探討

Frequency Allocation and Deployment Analysis in Taiwan LTE-A System

陳思怡(Sih-Yi Chen)

指導教授 ： 林信標

國立臺北科技大學/電資學院/電腦與通訊研究所/碩士(2014年)

https://doi.org/10.6841/NTUT.2014.00233

摘要

在現今無線通訊系統中，台灣已邁向了4G系統，而智慧型手持式裝置(Smart Handheld Devices, SHD)使用者用戶的增加，使用者對於無線傳輸的需求及品質的要求逐漸增加。但是，在細胞邊緣的使用者常因離基地台距離較遠，在傳輸通道上因路徑損耗效應造成傳輸品質及系統容量較差，以及來至其他基地台的細胞間干擾(Inter Cell Interference, ICI)的影響，常常造成邊緣使用者(Cell-Edge User, CEU)效能較低的緣故。
目前，對於提升CEU之效能已有許多文獻針對連續頻段進行頻率重複使用(Frequency Reuse)之規劃，但在台灣標到4G頻段之業者，頻段明顯幾乎呈現非連續之情形。在本論文中，會針對台灣目前各業者頻譜之得標情形，提出適用於台灣非連續頻段之頻率重複使用方案，此方法就是協調鄰近的基地台不要在同一個頻段使用相同的功率發射信號，以有效降低干擾。並建構出一個無線通訊系統的模擬軟體平台，能隨機或固定佈建使用者及基地台位置，並可依據路徑損耗、遮蔽效應及頻率重複使用方案來進行更變，最後分別計算出每位使用者的訊號-干擾雜訊比(SINR)、資料傳輸容量(Capacity)及吞吐量(Throughput)。
對於頻率重複使用方案上，本論文模擬各方案在非連續頻譜之情形，最後結果呈現出各家業者皆是以軟性部分頻率重複使用(Soft Fractional Frequency Reuse, SFFR)方案擁有較佳的傳輸容量及吞吐量，並可有效提高細胞邊緣使用者(CEU)之SINR，減少邊緣使用者之干擾。並利用各種頻率重複使用方案運用在現今台灣三大電信業者之現有頻段，模擬結果顯示為擁有最大連續20MHz之業者傳輸效能最佳。

關鍵字

頻率重複使用 ； 台灣LTE-A ； 頻譜規劃

並列摘要

With the rapid development of the wireless communications system, Taiwan has been toward to the 4G system. The quickly increasing of Smart Handheld Devices will cause the requirement of high transmission rate. However, cell-edge user (CEU) will cause poor transmission quality and system capacity due to the channel path loss effect. Also the inter cell interference (ICI) effect from other cell will cause the performance degradation of CEU.
There are some research have adapted Frequency Reuse scheme to reduce ICI for continuous frequency band allocation. However, 4G bands used in Taiwan area are non-continuous. In this paper, we proposed the suitable Frequency Reuse scheme for Taiwan’s 4G spectrum with non-continuous frequency band. Frequency Reuse method is used to coordinate the interference form neighbor cells. A system level communication simulation platform is developed. This simulation platform can randomly or fixed deploy location of users and base stations. Moreover, it can calculate the SINR, capacity, and throughput of mobile users according to shadowing effects and path loss effects with different Frequency Reuse pattern.
Based on the simulation platform, different frequency reuse schemes are used to evaluate the system performance of Taiwan’s three major cellular companies. Compared to other frequency reuse pattern, the result shows that the Soft Frequency Reuse (SFR) scheme has the best capacity and throughput. Also, the SFR scheme can improve the SINR value and decrease the interference on CEU efficiently. Besides, we find that the company which has 20MHz continuous frequency band reaches the best transmission performance.

並列關鍵字

Frequency Reus ； Taiwan LTE-A System ； Frequency Allocation

參考文獻

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