RFID Bracelet with Alerts

I need an engineering sample of the following: Two RFID Bracelets. One is passive the other is active. When the active bracelet stops identifying the passive bracelet, the active bracelet sounds an alert (beeping sound) and vibrates, (The active bracelet does not have to be in the form of a bracelet. It can be a plastic device that you put in your bag i.e.) The minimal distance needed is 5 meters. Meaning- the active bracelet will sense the passive bracelet for 5 meter. After the active bracelet leaves the ~5 meter range, the alert and vibration turns on until enters into range again. The active bracelet may relay on battery. For more information please contact me. Thank you