Wifi device with directional antenna and programmable power

antennawifiwireless

I need to set up a cheap device for an experiment that sends Wifi signal in a single direction but also allows me to set the power level on the Wifi signal.

I've tried to find a solution and looked at Arduino shields etc. but haven't found anything suitable so far.

The requirements are:

  • Transmission to be able to be picked up by client device
  • SSID programmable
  • Power level programmable
  • Directional antenna (as narrow as possible)

I appreciate any help.

Best Answer

Directionali WiFi

To send WiFi in a "single direction" you need a directional antenna. How directional depends on your requirements for directionality.

WiFi is typically at about 2.4 GHz = 125mm wavelength.
Antennas able to provide directionality of a few degrees are able to be made using either multiple element structures such as Yagi antennas (getting on the high frequency side for these) or dishes (such as satellite TV antennas) or tubular waveguide type antennas (eg "Pringles cantennas" are well known in the amateur community). Formulae and software are available to allow construction of an antenna of a desired degree of directionality.

Other:

Power level control is usually a function of the equipment used and relatively low cost units that allow this are available.

Sending SSID etc if a purely software function. Arduini 'shields' which provide the required hardware functionality and suitable software are available. Asking questions in the Arduino community is recommended.


CANTENNAS

EXCELLENT DIY Cantenna page

From their page - not too hard to duplicate:

enter image description here


Many ideas here

Wikipedia - Cantenna - A few useful links.

Wayback DIY Cantenna page looks useful.
Their calculation page also waybacked

Buy a commercial one or kitset here links may be broken.