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Sending signals from laptop wifi adapter?

  1. Jan 25, 2014 #1
    From what I understand, laptops have a wireless adapter that sends radio signals at a specific frequency to connect to a wifi router.

    My guess is that the wireless adapter is some sort of radio wave emitter/reciever, and could in theory be used for any other purpose besides connecting to a wifi router. I suppose also that computers come by default with software for the adapter, that which allows me to see nearby routers and connect to them.

    But is there any way for me, as a simple user, to write my own software that can use the wireless adapter to send any information I want (with only the physical device's capabilities as a limitation)?

    For example, can I tell it to "emit a 3.1 GHz wave for 5 seconds and then stop." Or to broadcast "Hello world" using some mapping from strings to radio wave signals which can then be read by other devices using the inverse mapping. I don't care if the signal becomes meaningless for routers.

    I have no specific application in mind, I am just curious to know whether I have any control over the signals the wireless adapter sends/recieves. And if I do, can I control it the same way I can control an Arduino and tell it to turn LEDs on and off?
  2. jcsd
  3. Jan 25, 2014 #2


    Staff: Mentor

    Well Intel publishes the specs:


    It seems that the bands of transmission are fixed to specific bands so you can change that.

    However, you could communicate with other devices that can listen to those frequencies.

    One example are wifi spy tanks and aerial drones that act as wifi hotspots for you to connect to.


    The iPad app talks to the tank using a wifi connection. The tank provides a hotspot to connect to.
  4. Jan 26, 2014 #3


    User Avatar
    Gold Member

    Building a wifi controlled device is very different than trying to reprovision a wifi chip to communicate with a different device using a different protocol.

    The wifi chip 802.11 radio PHY and MAC are highly integrated and changing any part of that would be difficult. For example, the header structure, retry logic, packet format, error correction, and many other aspects of the protocol are totally hidden from the user. It is all based on the 802.11 spec.

    I tried to find a programmers reference manual for a wifi chip (broadcom, realtek) so you could see the high level at which it is programmed. You should look around.

    Regardless, you will need to find a reference manual for the chip in your laptop in order to understand what flexibility you may be able to exploit.
    Last edited: Jan 26, 2014
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