sending data through dtmf

Discussion in 'The Projects Forum' started by elengr, Oct 10, 2011.

  1. elengr

    Thread Starter New Member

    Feb 5, 2011
    15
    0
    I am planning to built a robot which can be controlled wirelessly. The robot should send data (temperature,photographs of places,etc) back to me which can be monitored on a computer. Can I use DTMF to achieve the purpose since GSM module is relatively expensive? If DTMF can be used then why GSM are more expensive.
     
  2. kubeek

    AAC Fanatic!

    Sep 20, 2005
    4,670
    804
    GSM costs more becuse:
    it has the RF section already built in
    it can transmit at much higher bit rates than DTMF can


    With DTMF you can transmit 4bits at a time, and I think transmitting 5 symbols per second is optimistic. That gives you 20 bits per second at most. that is 2.5 bytes per second, how long do you think transmitting a phtograph will take? For example a 640*480 image from a webcam could have 15-30kB with serious compression, that is 100-200 minutes to transmit one image.
     
  3. staroflaw

    New Member

    May 28, 2011
    5
    0
    Cant you use wifi?

    I made a wifi remote control car using a FON.
    I sent data through serial.
     
  4. elengr

    Thread Starter New Member

    Feb 5, 2011
    15
    0
    Is rf technology a better and economical option than DTMF? Which is better and why?
     
  5. kubeek

    AAC Fanatic!

    Sep 20, 2005
    4,670
    804
    Depends how much data you need to transfer. If you need to send 10 digits of a phone number, dtmf is enough. For higher transmit speeds you need better technology.
     
  6. BMorse

    Senior Member

    Sep 26, 2009
    2,675
    234
    do a search on MiWi, and ZigBee too, just some other options other than WiFi...
     
Loading...