Signal encoding identification
This signal is already after AM demodulation


That means this is only meaningful if the signal actually only contains information in its amplitude; luckily, most simple remotes just use some form of On-Off-Keying or Pulse Position Modulation.


  Is it possible to determine the encoding type only by looking at the signal?


If this really is just a signal that is either on or off, then this looks like on-off keying. But really, your visualization might have hidden a lot of relevant information.

This might be a lot. It might simply be that the receiver uses the clock it has, or derives its clock from the preamble. Then, it could just be on/off, or it could also be manchester encoded.