I am assuming that you are familiar with soldering and can solder on dot-matrix PCBs. If not I can still help you out.
First of all using infrared system is not recommended since it is ambient temparature dependent and during daylight/bright settings, the sensors don't perform as expected as well as their designed range in not very good.(the reason is that infrared signals are basically heat waves which the sun messes up if u are outside)
I bielieve that we can take another approach to solve your problem - Radio Frequency.
The benefits you get are - longer range (upto 100 metres), lesser distortion, and most importantly, ability to work in any condition.
Look out for some cheap RF Rx/Tx 434MHz module(receiver and transmitter pair) and a decoder/encoder pair like HT12D/E(google it). All components(EXcluding soldering equipment and PCB) should cost you no more than 10euro.
If you can get your hands on these, we can get started and ill help u by providing a schematic and steps.
It will be way cooler to build as well as save ur trusty arduino for other projects.