i do not recommend to use the IR LED. limited to its straight line transfer character,you do not use it in large angle range.
look at the si4432 chip producted by silicon labs,i did a project with it in a few years ago,everything is ok so far.
for simple and effective communication protocol,you'd better do not transfer one byte only. it's not difficult to setup
a strong protocol. but there are some necessary elements in a protocol,as follows:
sync head + function code + function content + crc + frame end
Just advise for refernece.