how can I build a paging (beeper) system?

I have to build a simple paging system which is going to be used inside a small building. There will be a stationary transmitter and beepers at people moving around the building. It is enough if I can send only one signal to them, I don't need complicated messages with numbers/letters, just a beep is enough. I have no information on how to build such a system, any suggestions where to begin, schemas, ideas, all kind of help very much appreciaed

It sounds a sample system. But each block is necessary such as transmitter, receiver, RF front-end, baseband, etc. Also, you should plan the frequency, modulatoin type, power, etc. I think modulation is necessary even just a beep signal is needed. Without modulation the beeper receiver can receive and response to any interference.

Yeah, modulation will be necessary sure. But which type of modulation and frequencies should be preferred? Will I be able to build such a system myself? The problem mainly lies in using RF indoors i guess. I used an RF system previously and I experienced many problems indoors with receiving the signal. That was a ready made RF system. I wonder if I can build a system myself from scratch for my own needs.

It's a big project to build the system from scratch and ensure its performance is well. Maybe you can start with some mature transceiver ICs.

Choose as simple modulation as you can. AM is fine when you just need some simple audio like a beep. You will have to make it at a open frequency like 433MHz. But then again most open frequency bands are used alot, so the likelihood of disturbances becomes higher.

Try to make an AM receiver at 433MHz as this is relatively simple as a start. Then do the transmitter. Just a thought.

Thank you for all the answers. I looked for them but could not fine any suitable ready-made transceivers. (it maybe because of the country I reside now) I was warned previously not to use AM modulation because of interferences, but maybe it is worth a try still. Thanks