I would like to get some thoughts regarding best design for a small active RFID tag and corresponding transmitter. I am a relative newbie in this arena, but the required functionality is quite simple, from the powered base station, upon pressing a button, a unique signal will be sent out. The tag will periodically listen for this signal and upon receiving this signal, will activate a small onboard LED light and audible buzzer/beeper. The transmission range should extend several hundred feet with cost and size (small as possible) the primary considerations.
Please reply if you have any design suggestions for onboard chip, transmission protocol, battery, etc.
Also, I am looking for a builder/manufacturer to produce a reasonably priced prototype for me (and depending on effectiveness, possibly additional production). Do you have any suggestions for individuals/companies who provide this service?
Thanks!