超小型人工衛星を用いた地上センサーデータ収集のための長距離微小電力通信における研究九州工業大学 工学部 宇宙システム工学科

趙研究室

191A2021 悦永裕大
指導教員: 趙孟佑

LoRa とは省電力且つ長距離通信を目的に開発された変調方法である. 近年その技術検証は IoT を実現する一つの手段として議論されてきた. S&F システムとはストア＆フォワードの略称であり人工衛星を利用したデータ輸送である. 本システムでは超小型人工衛星を用いた IoT ミッションの一つとして認識されており, 更に LoRa 通信を含めた LPWAを基本とする通信方法が用いられ, それらは地上のセンサーターミナルと人工衛星を繋ぐ役割を担う. 本研究では, 九州工業大学で開発された 6U CubeSat KITSUNE を用いた S&Fミッションの実証をイタリア-日本間で実施する. また地上センサーターミナルから衛星へのアップリンクの際に用いる LoRa 通信においてその実現性を考察する.

Research on Long-Range micropower communicationfor terrestrial sensor data acquisition using CubeSat
Kyushu Institute Of Technology, Department of Space System Engineering, Cho laboratory
191A2021

Yudai Etsunaga

Supervisor: Prof. Mengu ChoLoRa is a modulation method designed for low-power, long-distance communications,and its utility and verification have recently been getting popular as one of means ofcommunication for building IoT networks. S&F system, which stands for Store & Forward is away of data transportation via satellite. It is also recognized as one of the CubeSat missions relatedto IoT, moreover, it is expected that LPWA-based communication including LoRa will be appliedto connect the ground sensor terminal and the satellite in this system. In this research, the 6U
CubeSat, KITSUNE developed by Kyutech will be used to demonstrate the S&F mission between
Italy and Japan using LoRa transceivers, which is one of the main objectives of KITSUNECubeSat. Moreover, it considers the feasibility of LoRa communication for ground to satellite
applications.

Table of Contents
List of acronyms...........................................................................................................................51.

Introduction ..........................................................................................................................62.

KITSUNE project ...............................................................................................................10

3.

LoRa ................................................................................................................................... 11
3.1 LoRa Modulation .......................................................................................................... 11
3.2 Spreading Factor ...........................................................................................................13
3.3 Code Rate ......................................................................................................................143.4 Signal Bandwidth ..........................................................................................................14
3.5 Packet Structure.............................................................................................................15

4.

Design of QFH antenna ......................................................................................................15
4.1 Background ...................................................................................................................15
4.2 Design of the first model ...............................................................................................16
4.3 Design of the second model...........................................................................................21
4.4 Long-Range Test of the fist model.................................................................................25

5.

Data uplink to KITSUNE ...................................................................................................27
5.1 Data packet format ........................................................................................................27
5.2 GST configuration .........................................................................................................27
5.2.1

Breadboard model ..................................................................................................29

5.2.2

GST board ..............................................................................................................30

5.3 Data uplink ....................................................................................................................32
5.3.1

Success of S&F mission .........................................................................................33

5.3.1.1

Case 1 ..............................................................................................................33

6.

Discussion .........................................................................................................................36

7.

Continuing collaboration with University of Rome Sapienza ............................................38

8.

Conclusion ........................................................................................................................38

9.

Bibliography......................................................................................................................39

10. Appendix ...........................................................................................................................41
10.1

Transmission code on the breadboard model ...............................................................41

10.2

Transmission code on the GST board (Temperature sensor data) ................................44

10.3Transmission code on the GST board (Temperature and pressure sensor data) ...........49

10.4

Receiving code for 10 bytes data packet format ..........................................................55

10.5

Receiving code for 16 bytes data packet format ..........................................................58

10.6

Passage propagation code on MATLAB ......................................................................62

10.6

Data type .....................................................................................................................67
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