close range radio communication

Discussion in 'General Electronics Chat' started by Spence, Jan 8, 2011.

  1. Spence

    Thread Starter Member

    Apr 23, 2010
    I need some type of radio communication between 2 mobile robotic devices, they need to be aware of each other when they are too close, 1-2 metres.

    They don't need to communicate (data) with each other, just be aware of each other. A microcontroller will control the logic.

    The big problem is that I haven't got a scope, so it's a bit difficult to design my own thing. There are lots of circuits available on the net, I've built some of them and they haven't worked. I can't afford to go through a massive learning curve because I've got two or three projects on the go.

    What I'm asking for is some advice, what should I be looking at, frequency, modulation etc., and if there's a tried and tested circuit you could recommend.

    *power 9v rechargeable power pack
    *aerial if vertical 6" max
  2. beenthere

    Retired Moderator

    Apr 20, 2004
    Radio would be exceptionally difficult to arrange as a guide to distance. A continuous broadcast is not going to have some sharp detection limit.

    A possible method is to have each equipped with an oscillator and speaker. The tone could be received by the other robot with a microphone and filtered amplifier. The loudness could be the determinant of how close they are.