近來無人飛行載具發展迅速，越來越多領域都可以搭配其彈性高以及容易上手的特性，發展出比以往更具效率且創新的應用模式，例如:地形探勘、高空拍攝、載送物資…等，也因為結合了全球定位系統(Global Positioning System，GPS)，操作模式由以往純手動進化為自動駕駛，不僅大幅降低整體操控難度，也增加了飛行的安全性與穩定性。無線通訊發展迅速，頻譜使用的管理也顯得越來越重要，如何確實掌握並有效的管理頻譜資源更是相關監理單位的重點業務之一，近來發生大陸廣播電台訊號干擾到台灣本島現行有在使用的頻段，如何找到干擾源並設法排除相關干擾也是一大課題。軟體定義無線電也是近來廣受討論的通訊技術，提供使用者一個可擴充性與可調整性皆很高的無線通訊平台，支援軟體定義無線電的硬體設備種類越來越多，技術也日益精進，本研究選用RTL-SDR作為訊號接收的硬體設備，其價格相對較低，體積較小、也較符合本研究的需求。
本研究採用自組旋翼式無人飛行載具，搭載微型電腦樹莓派(Raspberry Pi)以及RTL-SDR，建構出一套簡易的頻譜監測系統，針對台灣民視無線電視台所發射之數位電視訊號，進行訊號強度地蒐集，透過與無人飛行載具之繞圈模式結合，找出訊號強度最強在哪個方向角，進而達到測向的目的，最後更透過在不同地點、多組的測向結果，針對發射站台做一初步的定位。

Recently, unmanned aerial vehicles have been developed rapidly. They can be used in many areas due to their high flexibility, the characteristics of easy to learn, and fast design process. Also, wireless communication is developing rapidly, and it needs a large amount of spectrum. Hence, spectrum management is becoming more and more important. The main purposes of spectrum management are to increase spectrum usage efficiency, decrease interference, and clear unauthorized use of radio spectrum. Spectrum monitoring provides the required process as the eyes and ears of the spectrum management. In spectrum monitoring, positioning an interference station is one of the core tasks. Software-defined radio (SDR) has also been widely developed so that more and more types of SDR hardware can be found in the market. For example, RTL-SDR is a low cost, sufficient bandwidth SDR device. This study attempts to build a prototype of mobile spectrum monitoring station and would select RTL-SDR as a signal receiver in the spectrum monitoring system. The prototype monitoring system can be used to collect digital TV signals in Taiwan. This system uses an unmanned aerial vehicle carrying an RTL-SDR device connected a directional antenna to find the direction of a radio station. Combining at least two radio directions, we can reach the goal of positioning a radio station

[1] 內政部國土測繪中心，“無人飛行載具系統簡介，” https://www.nlsc.gov.tw/UAS/2-1_UASintroduce.html
[2] 每日頭條，“深度——一起認識SDR軟體定義無線電，” https://kknews.cc/zh-tw/tech/z6v4eq.html
[3] 何承勳，“以無人飛行載具搭載軟體定義無線電建置空中頻譜監測站，”碩士論文，電信管理研究所，國立成功大學，台南市，2016.
[4] A. Nafkha, M. Naoues, K. Cichon, and A. Kliks, “Experimental spectrum sensing measurements using USRP Software Radio platform and GNU-radio,” 2014 9th International Conference on Cognitive Radio Oriented Wireless Networks and Communications (CROWNCOM), Oulu, Finland, 2014, pp. 429-434.
[5] G. J. Toussaint, P. De Lima, and D. J. Pack, “Localizing RF Targets with Cooperative Unmanned Aerial Vehicles,” 2007 American Control Conference, New York, NY, 2007, pp. 5928-5933.
[6] 民視，“如何收看民視數位無線電視，” http://www.ftv.com.tw/howtoftv01.aspx
[7] 張古東，“以軟體定義無線電實作頻譜監測系統，” 碩士論文，電信管理研究所，國立成功大學，台南市，2014.
[8] J. Mitola, “Software radios: Survey, critical evaluation and future directions,” in IEEE Aerospace and Electronic Systems Magazine, vol. 8, no. 4, pp. 25-36, Apr. 1993.
[9] 柯琮寶，“以軟體定義無線電技術建置電波監測系統之頻寬需求，” 碩士論文，電信管理研究所，國立成功大學，台南市，2015.
[10] 施旻汶，“自動化無人飛行載具輔助擷取橋梁影像之研究，” 碩士論文，營建管理研究所，國立中央大學，桃園市，2014.
[11] W.-T. Chen and C.-H. Ho, “Spectrum monitoring with unmanned aerial vehicle carrying a receiver based on the core technology of cognitive radio – A software-defined radio design,” Journal of Unmanned Vehicle Systems, vol. 5, no. 1, pp. 1-12, 2017.
[12] R. Danymol, T. Ajitha, and R. Gandhiraj, “Real-time communication system design using RTL-SDR and Raspberry Pi,” 2013 International Conference on Advanced Computing and Communication Systems, Coimbatore, India, 2013, pp. 1-5.

[13] W.-T. Chen, K.-T Chang, and C.-P. Ko, “Spectrum monitoring for wireless TV and FM broadcast using software-defined radio,” Multimedia Tools and Applications, vol. 75, no. 16, pp. 9819-9836, 2015.
[14] M. Jakubiak, “Cellular network coverage analysis using UAV and SDR,” M.S. thesis, Dept. Electron. and Comm. Eng., Tampere Univ. of Tech., Tampere, Finland, 2014.
[15] 馮仕龍，“多旋翼無人飛行載具通訊系統建置，” 碩士論文，電子工程研究所，國防大學理工學院，桃園市，2016.
[16] I. Llamas-Garro, K. Lukin, M. T. de Melo, and J. M. Kim, “Frequency and angular estimations of detected microwave source using unmanned aerial vehicles,” 2016 IEEE MTT-S Latin America Microwave Conference (LAMC), Puerto Vallarta, Mexico, 2016, pp. 1-3.
[17] iThome，“Google Maps利用手機基地台提供定位服務，” http://www.ithome.com.tw/node/46499.
[18] DearHoney數位音樂工作室，“Google WiFi 定位的原理，” https://www.dearhoney.idv.tw/1293/google-wifi-%E5%AE%9A%E4%BD%8D%E7%9A%84%E5%8E%9F%E7%90%86/
[19] Pixhawk Overview. [Online]. Available: http://ardupilot.org/copter/docs/common-pixhawk-overview.html
[20] Copter，“連接電變與馬達(Pixhawk)，”http://copter.ardupilot.tw/initial-setup/assembly-instructions/connect-escs-and-motors-pixhawk/.
[21] Installing Mission Planner — Mission Planner documentation. [Online]. Available: http://ardupilot.org/planner/docs/common-install-mission-planner.html.
[22] 915 MHz (American) Telemetry Radio Set - 3DR. [Online]. Available: https://store.3dr.com/products/915-mhz-telemetry-radio.
[23] 大城科技，“產品資訊-數位電視天線DA-2610戶外高級型，”http://www.u99.com.tw/show_sample_list.asp?prodid=120112229556&g=awp_trax&l=tw
[24] Circle Mode — Copter documentation. [Online]. Available: http://ardupilot.org/copter/docs/circle-mode.html.
[25] Rtl Power: Basic scripting. [Online]. Available: http://kmkeen.com/rtl-power/.
[26] Google Map. [Online]. Available: https://www.google.com.tw/maps/.
[27] Vincenty solutions of geodesics on the ellipsoid in JavaScript | Movable Type Scripts. [Online]. Available: http://www.movable-type.co.uk/scripts/latlong-vincenty.html.
[28] Helping you with gnuplot. [Online]. Available: http://www.gnuplot.info/help.html.