|Quoting SP90 (Reply 10):|
First question is how exactly does the PTV systems work on planes? Are the contents stored on a central server on the plane or received real time via satellite connection?
There are three ways that PTVs work and all ways are in use and vary in technology. The first PTVs were powered by cassette players found in a galley. There are usually 8-16 cassette players and they play the movies on the channel system that is wired to each of the seats.
The second and more advanced IFE systems are AVOD systems. They have a computer hard drive that stores all the video programming, and the individual PTV computers play the movies upon the passengers request. These are more advanced, but are also more prone to failure and can be slow.
The third type is satellite tv/radio. This was pioneered by jetBlue where they use existing satellite television and have a reciever on the plane. It works like normal cable for the most part.
As for IFE of the seats that the original poster is referring to, if there are PTVs, they most likely would be of the cassette type since AVOD and satellite tv have only been around for a few years and those seats aren't being replaced.
If you have never designed an airplane part before, let the real designers do the work!