Detector Circuit

Discussion in 'The Projects Forum' started by fuzail, Oct 3, 2010.

  1. fuzail

    Thread Starter New Member

    Oct 3, 2010
    My project involves checking the presence of a device in a room. The device would have some kind of transmitter attached to it.
    The receiver is supposed to send a high signal to a micro controller only when the device is detected in the room else send a low signal or vice versa.

    I need some suggestions how i can go about implementing this ?
  2. wayneh


    Sep 9, 2010
    Isn't this exactly what RFID is for? I'd start by researching that.
  3. marshallf3

    Well-Known Member

    Jul 26, 2010
    First of all it can't be RF related or it will go through any area that isn't totally shielded, that leaves you with light or sound.

    Sound will be able to carry through walls to some extent depending on frequency, level and construction of the walls but is a good candidate. Ultrasonic is probably the best choice for this.

    Infrared light, especially if aimed up and bouncing off a ceiling of some color other than blue or green, (cyan is the exact opposite) carries pretty well and might be your best choice if something interferes with the use of sound.