RF Transmission & Receiving Questions

Is there a way to direct a RF signal at a specific RF device (ie like pointing it at the specific device similar to what you'd expect in a line of sight IR scenario), even if there are other RF devices in the same room? I like the benefits of RF being able to travel a great distance, but am trying to overcome a scenario where i can send the signal via RF, but that its not received by identical other devices.

what im trying to accomplish is a scenario where a signal can be transmitted (and ideally have a reply / response received back as well) over a distance of approximately 30 ft to a specific RF device, but without the scenario of sending that same signal to an unintended other (similar or identical) RF device.

I've heard of Z-wave, and it seems like that technology might reach the distance I'm looking for, but i don't know how to address the other concern of transmitting unintentionally to other RF devices. Is there something better or different then Z-wave that achieves hat I'm looking for.

Any thoughts of this being easier to be accomplished via a laser or some sort of RF & laser combination??
Thanks in advance.

In a brief, it doesn't work with RF transmission. Z-wave is an example of using unique addresses to select a receiver, that's a practical concept. It works with wireless keys, cell phones and more.

Why don't you add decoder at the receiver so that each receiver has it's unique code.

There is no way to send RF energy to selective device only. Any other RF device will get at least part of RF energy. There are some methods to separate devices. It may be frequency division or time division as the easiest methods. Some kinds of spread spectrum signals are also possible like UWB, TDMA, CDMA, OFDM, etc. The best choice will depend on your application. There are a lot of vendors who have practically ready to go solution as RF ICs. Usually they are simple and require a few parts to be added to the chip.