Some guidelines on picking wireless frequencies

Wireless can be something of a black art, and there are a dizzying array of standards and choices. Here are some simple guidelines to help you pick wisely:

  • --We operate in four frequency ranges: 72Mhz (RC gear), 900 Mhz (video and telemetry), 1.3 Ghz (video) and 2.4 GHz (RC, video and telemetry), not including GPS, which is a passive receiver only.
  • --It is a BAD IDEA to have transmitters and receivers in the same frequency range right next to each other, so you'll want to choose your equipment to avoid this.
  • --In general, the lower the frequency the longer the range because it can go around obstructions better, so 900 Mhz video tends to have longer range than 2.4Ghz video. But digital transmission technology can more than compensate for that, so it's not a hard-and-fast rule. For instance, a high-end spread-spectrum 2.4GHz wireless video setup can outperform a lower-end 900 Mhz one.
  • --Some frequency ranges are more crowded than others. For instance, indoors and in urban environments 2.4GHz has to compete with everything from WiFi to Bluetooth to cordless phones. 900Mhz just competes with some cordless phones.


So, for example, you could try these configurations:

 

Configuration One: RC: 2.4Ghz. Xbee 900Mhz. Video: 1.3 Ghz

 

Configuration Two: RC 2.4 Ghz, Xbee 900Mhz, Video 2.4Ghz, with antenna as far from RC as possible

 

Configuration Three: RC: 72 Mhz, Xbee 900Mhz, Video 2.4 Ghz.

Views: 3750


3D Robotics
Comment by Chris Anderson on January 9, 2012 at 9:43pm

japi: sorry, typo. Fixed. 


Moderator
Comment by Ruwan on January 9, 2012 at 9:48pm

thanks Chris.

Comment

You need to be a member of DIY Drones to add comments!

Join DIY Drones

© 2020   Created by Chris Anderson.   Powered by

Badges  |  Report an Issue  |  Terms of Service