Introduction » History » Version 5
Version 4 (AUGER, Anne sophie, 03/23/2015 09:43 AM) → Version 5/10 (AUGER, Anne sophie, 03/23/2015 09:48 AM)
h1. Introduction
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:
* regulatory aspects : we must find a frequency band, either license-free or requiering rights of emission
* link budget aspects : some parameters can be adjusted to reach the wanted performance
* flight constraints have to be considered in the choice of the equipment to allow a full time link
p=. !Slide1.jpeg!
To summarize the system design constraints, we can fill the mission statement below:
p=. !cahier_des_charges.png!
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:
p=. Bit rate = FPS*5,0692 * L ^1,391^ /(1000*AR)
So
p=. *Bit rate=322 Kbps*
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 bit rate of 500 kbps.
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:
* regulatory aspects : we must find a frequency band, either license-free or requiering rights of emission
* link budget aspects : some parameters can be adjusted to reach the wanted performance
* flight constraints have to be considered in the choice of the equipment to allow a full time link
p=. !Slide1.jpeg!
To summarize the system design constraints, we can fill the mission statement below:
p=. !cahier_des_charges.png!
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:
p=. Bit rate = FPS*5,0692 * L ^1,391^ /(1000*AR)
So
p=. *Bit rate=322 Kbps*
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 bit rate of 500 kbps.