One option is to use off-the-shelf 433MHz RX and TX modules ..
Datasheets for the Laipac TLP-434 transmitter and RLP-434 receiv-er modules are available from www.laipac.com. Compatible 433MHz modules are available from all major kit suppliers. Oatley Electronics sells the encoder and decoder ICs (stock codes SM5162RF & SM5172RF). Check ’em out at www.oatleye.com, with datasheets available from www.samhop.com.tw.