Introduction » History » Version 3

AUGER, Anne sophie, 03/23/2015 09:42 AM

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h1. Introduction
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The aim of this project is the design study of a Telemetry and Telecommand (TM/TC) link between small aircrafts (ie TB20) and an antenna on top of ISAE building. There are different aspects in this work: 
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* regulatory aspects : we must find a frequency band, either license-free or requiering rights of emission
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* link budget aspects : some parameters can be adjusted to reach the wanted performance
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* flight constraints have to be considered in the choice of the equipment to allow a full time link
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To summarize the system design constraints, we can fill the mission statement below:
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In order to define the video bit rate required for our application, knowing the aspect ratio (AR=1,78) quality of the encoded video (L=720p) and its frame cadence (FPS=12), we used the following formula:
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p=. Bit rate = FPS*5,0692 * L ^1,391^ /(1000*AR) 
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So 
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p=. *Bit rate=322 Kbps*
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As the link will allow video transmission, we will need an adapted encapsulation protocol, so we must take into account extra bits: we decide to define a video bit rate of 500 kbps.