近年來無人飛行系統的應用逐漸成為主流討論的議題，從原本應用於軍事方
面拓展到大眾以及商業上的應用，如交通壅塞地區的監控系統、高危險救災地區
的偵測視察甚至大範圍農業的農作物狀態監控等。
在本篇論文目標致力於設計一格無線通訊系統應用於無人飛行系統上，而主
要使用情境為將無人機空拍的影像傳輸回基地台。在本篇論文裡分為兩個主要目
標，第一為頇達到45 百萬位元(Mbps)每秒的資料傳輸量，在最高飛行速度為200
公里每小時的情況下，第二則為在達到743.5 公里每小時相較於第一目標更高速
的飛行通道下達到3.5 百萬位元每秒的資料傳輸量。我們透過參考L 頻帶數位飛
航通訊系統(LDACS1)以及多篇討論飛航通道的文獻訂定出適用於我們情境下的
傳輸通道模型。透過正交分頻多工系統(OFDM)系統的參數設計以及模擬結果在
合理範圍內挑選最適用於該情境的系統參數。我們分別選用了256 點以及2048
點的快速傅立葉轉換(FFT)，分別擁有31.25 千赫茲(kHz)以及7.63 千赫茲子載波
頻寬和8微秒(μs)的循環字首(cyclic prefix)來克服通道的不理想特性。最後提出
的傳收端為結合空頻區塊碼(SFBC)二傳輸天線對一接收天線的系統架構，以及
里德索羅門碼(Reed Solomon code)加上迴旋碼(convolutional code)的錯誤更正碼；
兩項技術分別至少提供增進了8 分貝(dB)以及3.75 分貝的系統效能。在最後討論
也顯示出在系統接收端同步部份加上不理想特性的模擬結果。

For the past few years, the application of unmanned aircraft vehicles (UAVs), or unmanned
aircraft system (UAS) have been a rising issue. Except for the military aspect, they widely
used on inspecting the highly risky fields such as volcanic eruption, agriculture with sensor
detect soil, crop and water condition or conflagration for science research and firefighter res-
cue.
In the thesis, our goal is to design a communication system applied on the UAVs. The
scenario is the unmanned aircraft vehicles equipped camera to transmit the video through the
ground station. There are two cases in our scenario, first has maximum cruise speed 200km
per hour, the distance from the ground station to aircraft has 150km and a data rate 45Mbps
required. Another case has maximum cruise speed 0.7 Mach number (743.5km per hour) and
also has 150km transmission distance. We define the aeronautical channel respectively, calcu-
late the link budget, then an OFDM system based design is presented. The system parameters
such as subcarrier spacing, cyclic prefix length and the pilots arrangement evaluation which is
effected by the different Doppler frequency, delay spread and data rate requirement. We pro-
posed an OFDM system with 256 and 2048 fast Fourier transform (FFT) size, which has large
subcarrier spacing 31.25kHz and 7.63kHz with 8s cyclic prefix (CP) duration to overcome
the frequency-selective fading channel. The proposed transceiver includes two transmitters
and one receiver with space frequency block code and channel coding which concatenated
Reed Solomon (255,239) codes and convolutional codes, both the techniques can improve
8dB and 5dB compared with the single input and single output OFDM system respectively.
The timing and frequency synchronization are also discussed.

Abstract i
1 Introduction 1
1.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.3 Main Contributions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.4 Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2 Related Works on Aeronautical Communication and Specification 5
2.1 Aeronautical Data Network . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2.2 Unmanned Aircraft Vehicles (UAVs) . . . . . . . . . . . . . . . . . . . . . . 5
2.3 Orthogonal Frequency-Division Multiplexing (OFDM) . . . . . . . . . . . . 6
2.4 L-Band Digital Aeronautical Communication System (L-DACS) . . . . . . . 8
2.5 Digital Video Broadcasting (DVB) series . . . . . . . . . . . . . . . . . . . 9
2.6 Related System Comparison . . . . . . . . . . . . . . . . . . . . . . . . . . 12
3 Wireless Channel Model 13
3.1 Wireless Channel Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
3.1.1 Wide-sense Stationary with Uncorrelated Scattering (WSSUS) Chan-
nel Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
3.1.2 Link Budget . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
3.1.3 Aeronautical Channel Modeling . . . . . . . . . . . . . . . . . . . . 20
3.1.4 Proposed Channel Model . . . . . . . . . . . . . . . . . . . . . . . . 27
4 System Design 29
4.1 System Target . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
4.2 System Parameter Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.3 Channel Equalization and Pilot Pattern Arrangement . . . . . . . . . . . . . 35
4.4 Antenna Diversity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
4.5 Error Correcting Code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
4.6 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
5 System Implementation and Synchronization Simulation 49
5.1 System Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
5.2 Synchronization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
5.2.1 Coarse Symbol Timing Detection . . . . . . . . . . . . . . . . . . . 53
5.2.2 Fine Symbol Timing Detection . . . . . . . . . . . . . . . . . . . . . 54
5.2.3 Carrier Frequency Offset . . . . . . . . . . . . . . . . . . . . . . . . 56
5.2.4 Sampling Clock Offset . . . . . . . . . . . . . . . . . . . . . . . . . 58
5.2.5 Carrier phase offset . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
5.3 System Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
6 FutureWorks and Conclusion 63
6.1 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
6.2 Future Works . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63

[1] T. D. Chiueh, P. Y. Tsai, I. W. Lai, Baseband Receiver Design for Wireless MIMO-
OFDM Communications, 2nd Edition, 2009 :Wiley.
[2] L. Gupta, R. Jain and G. Vaszkun,”Survey of Important Issues in UAV Communication
Networks”,in IEEE Communications Surveys & Tutorials, vol. 18, no. 2, pp. 1123-1152,
Secondquarter 2016.
[3] Maria de,Unmanned Aerial Vehicle: An Overview, InsideGNSS, January 2008
[4] ETSI TS 01 545-1 V1.2.1 (2014-04), Second Generation DVB Interactive Satellite Sys-
tem (DVB-RCS2); Part 1: Overview and System Level specification
[5] M. Schnell, U. Epple, D. Shutin and N. Schneckenburger, ”LDACS: future aeronautical
communications for air-traffic management,” in IEEE Communications Magazine, vol.
52, no. 5, pp. 104-110, May 2014.
[6] IEEE 802.11g Further Higher Data Rate Extension in the 2.4 GHz Band, available on-
line at http://standards.ieee.org/getieee802/download/802.11g-2003.pdf.
[7] Y. Wang, M. C. Ertrk, H. Arslan, R. Sankar, I. h. Ra and S. Morgera, ”Throughput and
delay analysis in Aeronautical Data Networks,”Computing, Networking and Communi-
cations (ICNC), 2012 International Conference on, Maui, HI, 2012, pp. 771-775.
[8] Nasa projects web site, NASA, ACAST. [Online]. Available:
http://acast.grc.nasa.gov/main/projects/
[9] Newsky project, EU, Newsky Project, 2008, 21271.
[10] ITU-R, Characteristics of unmanned aircraft systems and spectrum requirements to sup-
port their safe operation in non-segregated airspace, Report ITU-R .2171, Dec. 2009.
[11] Y. Zeng, R. Zhang and T. J. Lim, ”Wireless communications with unmanned aerial ve-
hicles: opportunities and challenges,” in IEEE Communications Magazine, vol. 54, no.
5, pp. 36-42, May 2016.
[12] T. Hwang, C. Yang, G.Wu, S. Li and G. Y. Li, ”OFDM and ItsWireless Applications: A
Survey,” in IEEE Transactions on Vehicular Technology, vol. 58, no. 4, pp. 1673-1694,
May 2009.
[13] STATFOR, the EUROCONTROL Statistics and Forecast Service, Challenges of
Growth, Task 4: European Air Traffic in 2035, EUROCONTROL, June 2013;
http://www.eurocontrol.int/statfor
[14] S. Brandes, U. Epple, S. Gligorevic, M. Schnell, B. Haindl and M. Sajatovic, ”Physi-
cal layer specification of the L-band Digital Aeronautical Communications System (L-
DACS1),”2009 Integrated Communications, Navigation and Surveillance Conference,
Arlington, VA, 2009, pp. 1-12.
[15] ETSI EN 102 377 V1.1.1(2005-02), DVB-H Implementation Guide
[16] ETSI EN 101 190 V1.1.1 (1997-12), Implementation Guidelines for DVB-T Services,
Transmission Aspects
[17] G. Faria, J. A. Henriksson, E. Stare and P. Talmola, ”DVB-H: Digital Broadcast Services
to Handheld Devices,” in Proceedings of the IEEE, vol. 94, no. 1, pp. 194-209, Jan. 2006.
[18] Youping Zhao and Jinxing Li, ”Analysis of the impact of Doppler spread on OFDM-
based next-generation high-speed rail broadband mobile communications,” Communi-
cation Technology and Application (ICCTA 2011), IET International Conference on,
Beijing, 2011, pp. 116-120.
[19] R. Zhang, B. Ai, L. Yang, H. Song and Z. q. Li, ”A precoding and detection scheme
for OFDM based wireless communication system in high-speed environment,” in IEEE
Transactions on Consumer Electronics, vol. 60, no. 4, pp. 558-566, Nov. 2014.
[20] Rui Jiang, Youping Zhao and Jinxing Li, ”Optimization of mobile video transmission in
the high-speed rail environment,” Communications and Networking in China (CHINA-
COM), 2013 8th International ICST Conference on, Guilin, 2013, pp. 22-27.
[21] J. H. Jeon, H. An and S. J. Park, ”Design and implementation of bidirectional
OFDM modem prototype for high-speed underwater acoustic communication sys-
tems,”OCEANS 2016 - Shanghai, Shanghai, 2016, pp. 1-4.
[22] P. Kyosti, et al, WINNER II D1.1.2, WINNER II channel models, [Online Available]
https:// www.ist-winner.org/deliverables.html, September 2007.
[23] D. Pompili and I. F. Akyildiz, ”Overview of networking protocols for underwater wire-
less communications,” in IEEE Communications Magazine, vol. 47, no. 1, pp. 97-102,
January 2009.
[24] P. Hoeher, ”A statistical discrete-time model for the WSSUS multipath channel,” in IEEE
Transactions on Vehicular Technology, vol. 41, no. 4, pp. 461-468, Nov 1992.
[25] M. Patzold, U. Killat, F. Laue and Yingchun Li, ”On the statistical properties of de-
terministic simulation models for mobile fading channels,” in IEEE Transactions on
Vehicular Technology, vol. 47, no. 1, pp. 254-269, Feb 1998
[26] Walter Debus, RF Path Loss & Transmission Distance Calculations, Technical Memo-
randum, August 4, 2006
[27] Deutsches Zentrum fur Luft und Raumfahrt (DLR), Expected B-AMC System Perfor-
mance, Doc. ref. CIEA15EN506.11, 2007.
[28] N. Neji, R. de Lacerda, A. Azoulay, T. Letertre and O. Outtier, ”Survey on the Future
Aeronautical Communication System and Its Development for Continental Communica-tions,” in IEEE Transactions on Vehicular Technology, vol. 62, no. 1, pp. 182-191, Jan.
2013.
[29] ICAO, Amendment 82 to the international standards and recommended practices aero-
nautical telecommunications, Feb 2007
[30] ICAO, Regional Preparatory Group Meeting for World Radio communication Confer-
ence 2007 (WRC-2007) ACP Working Group B and F and NSP SSG Meetings, Feb
2007
[31] P. A. Bello, Aeronautical channel characterization, IEEE Transaction on Communica-
tions, vol. 21, no. 5, pp. 548563, May 1973.
[32] J. Painter, S. C. Gupta, and L. R. Wilson, Multipath modeling for aeronautical commu-
nications, IEEE Transaction on Communications, vol. 21, no. 5, pp.658662, May 1973.
[33] A. Neul et al., Propagation measurements for the aeronautical satellite channel, IEEE
Vehicular Technology Conference, vol. 37, pp. 9097, June 1987.
[34] E. Haas, Aeronautical channel modeling, IEEE Transactions on Vehicular Technology,
vol. 51, no. 2, pp.254 -264, Mar. 2002
[35] Deutsches Zentrum fur Luft und Raumfahrt (DLR), Updated LDACS1 System Specica-
tion, Doc. ref. EWA04-1-T2-D1, 2011.
[36] M. Failli, Digital land mobile radio communications, COST 207 Final Rep., Sept. 1988.
[37] A. A. Hutter, ”Design of OFDM systems for frequency-selective and time-variant chan-
nels,” Broadband Communications, 2002. Access, Transmission, Networking. 2002 In-
ternational Zurich Seminar on, Zurich, 2002, pp. 39-1-39-6.
[38] Meng-Han Hsieh and Che-Ho Wei, ”Channel estimation for OFDM systems based on
comb-type pilot arrangement in frequency selective fading channels,” in IEEE Transac-
tions on Consumer Electronics, vol. 44, no. 1, pp. 217-225, Feb 1998.
[39] J. D. Parsons, The Mobile Radio Propagation Channel, 2nd Edition, 2000,Wiley, pp330-
335.
[40] Hongwei Yang, Dong Li, Switched STBC and SFBC, IEEE 802.16m-08/016r1 Call for
Contributions on Project 802.16m System Description Document, ,May 2008
[41] N. Nyirongo, W. Q. Malik and D. J. Edwards, ”Concatenated RS-Convolutional Codes
for Ultrawideband Multiband-OFDM,” 2006 IEEE International Conference on Ultra-
Wideband, Waltham, MA, 2006, pp. 137-142.
[42] P. Jacob, R. P. Sirigina, A. S. Madhukumar and V. A. Prasad, ”Cognitive Radio for
Aeronautical Communications: A Survey,” in IEEE Access, vol. 4, no. , pp. 3417-3443,
2016.
[43] U. Epple and M. Schnell, ”Overview of legacy systems in L-band and its influence on the
future aeronautical communication system LDACS1,” in IEEE Aerospace and Electronic
Systems Magazine, vol. 29, no. 2, pp. 31-37, Feb. 2014.
[44] M. C. Erturk, J. Haque, W. A. Moreno and H. Arslan, ”Doppler Mitigation in OFDM-
Based Aeronautical Communications,” in IEEE Transactions on Aerospace and Elec-
tronic Systems, vol. 50, no. 1, pp. 120-129, January 2014.
[45] A. Donner, C. Kissling and R. Hermenier, ”Satellite constellation networks for aeronau-
tical communication: traffic modelling and link load analysis,” in IET Communications,
vol. 4, no. 13, pp. 1594-1606, September 3 2010.