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AUGER, Anne sophie, 03/21/2015 07:54 PM
| 1 | 1 | AUGER, Anne sophie | h1. DESIGN OF A TM/TC LINK BETWEEN SMALL AIRCRAFT AND GROUND STATION |
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| 3 | 2 | AUGER, Anne sophie | h2. INTRODUCTION |
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| 5 | 2 | AUGER, Anne sophie | The aim of this project is the design of a Telemetry and Command link between small aircrafts (ie TB20) and an antenna on top of ISAE building. There are different aspects in this work: |
| 6 | 2 | AUGER, Anne sophie | * regulatory aspects : we must pay for rights of emission on a given frequency band |
| 7 | 2 | AUGER, Anne sophie | * link budget aspects : some parameters can be adjusted to reach the wanted performance |
| 8 | 2 | AUGER, Anne sophie | * flight constraints have to be considered to allow a full time link |
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| 10 | 2 | AUGER, Anne sophie | To summarize the system design constraints, we can fill the mission statement below: |
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| 12 | 4 | AUGER, Anne sophie | |_.Type of application|_.Communication link between small aircraft and ground station|_. | |
| 13 | 4 | AUGER, Anne sophie | |Minimum range|50 km|Line Of Sight| |
| 14 | 4 | AUGER, Anne sophie | |Fligh|| |
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| 19 | 1 | AUGER, Anne sophie | In order to define the video bit rate required for our application, knowing the quality of the encoded video (720p) and its frame cadence (12 fps) , we used the following formula : |
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| 21 | 4 | AUGER, Anne sophie | p=. Bit rate = FPS * 5,0692 * L ^1,391 / (1000 * AR) |
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| 23 | 1 | AUGER, Anne sophie | With AR = 1,78, FPS=12 and L=720 |
| 24 | 4 | AUGER, Anne sophie | So |
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| 26 | 4 | AUGER, Anne sophie | p=.Bit rate=322 Kbps |
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| 28 | 3 | AUGER, Anne sophie | As the link will allow data and video transmission, we choose to use the MPEG4 packet format, adapted for multiplexing different nature content. Therefore, we have to consider extra bits due to the encapsulation of data in MPEG4 frames, and we decide to define a bit rate of 500 kbps. |
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| 33 | 1 | AUGER, Anne sophie | h2. RESEARCH OF A FREQUENCY BAND |
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| 36 | 2 | AUGER, Anne sophie | h3. Issue of a free band |
| 37 | 1 | AUGER, Anne sophie | SYSTEM DESIGN CONSTRAINTS AND VARIABLES |
| 38 | 1 | AUGER, Anne sophie | SIMULATION OF THE LINK BUDGET PERFORMANCE |