Here is a little explanation of how this IR receivers work
http://www.societyofrobots.com/member_tutorials/node/102 ( in the area a little different from communications, but I believe it will be clear). The basics: we modulate our bit samples with 40 KHz (or 38 KHz, it is relatively wide-band, so 40 KHz receiver will most likely sense 38 KHz signal). Something like that: we a re sending 10101 pattern
1 0 1 0 1
______________________ ______________________ ___________________
_______| |________________| |____________________| | _
and modulate IR LED intensity.
__ __ _ __ __ _ __ __ __ _ __ __ _ __ __ __ _ __ __ _ __
________| |_| |_| |_| |_| |_| |_| |___________________| |_| |_| |_| |_| |_| |_| |_______________________| |_| |_| |_| |_| |_| |_| |__
Receiver demodulate it into initial pattern (text is formatted automatically, really second and third "one" bits look loke the first one)