The antenna will work identically for transmitting and receiving, so there is no limitation from the basic physics. The problem is purely one of overdriving a sensitive analog input, which is the receiver input. If the transmitter output is limited to the same power supply that the receiver runs on, this might not matter. It may temporarily make the receiver deaf for a short time after the transmission while its AGC recovers.
Look at the datasheet for the receiver carefully and see what the voltage limits are for the RF input pin. This is actually one of those rare cases where you may be able to use the absolute maximum limits instead of the operating limits if due care is used with all parameters. Your firmware knows when it is transmitting and can know to ignore anything from the receiver during that time and a short time afterward. During this time you only care that the receiver not be damaged.
A better all around solution would be to use a transceiver chip. These have the transmitter and receiver built into the same chip, with a single antenna connection. Whatever protection the receiver might need to not be hurt by transmitter RF levels has already been built in.
For data transmission / reception, one of the less expensive options today is a pre-built module around the nRF24L01+ Transceiver IC. These modules typically offer a built-in PCB-trace antenna, 250 Kbps to 2 MBPS bandwidth before error correction, and are tried and tested.
Most important, they save you time in debugging and antenna tuning. After thousands of people have used these modules, which are built on the manufacturer's reference designs after all, most of the kinks are pretty thoroughly ironed out. Also, being able to tap the experience of many others on the internet who have used such a module, counts for a lot when trying to resolve issues.
For instance, this listing on eBay is for a mere US$2.10 with free international shipping. It uses the 2.4 GHz band, which does not need licensing for low power use in most countries.
Another alternative is this 433 MHz band transmit / receive pair of modules (just 9.6 Kbps though), in case you specifically want to stay with transmit-only and receive-only designs. US$1.99 for the pair makes it pretty attractive.
Of course, in each case, you could as well build your own module starting from the IC manufacturer's reference design, and thus learn while implementing your radio functionality.
It is unlikely that the price advantage of massive volume production can be beaten, though.
Best Answer
You didn't provide any links to the modules or specifications.
The normal, no collision, method would be to poll each outstation: the controller sends out a request for data to each substation in turn and waits for a response. Some form of addressing is required. Assuming your radios can't do that you have a few choices.
In either case some form of error checking (by message checksum) should be used.