Yagi/Parabolic explained by an engineer

[bob_r]

Rick at Drone Valley is an engineer and explains in detail both the Yagi Uda range extenders and the Parabolic range extenders. Good Youtube channel.

 

[ShadowCat]

Rick at Drone Valley is an engineer and explains in detail both the Yagi Uda range extenders and the Parabolic range extenders. Good Youtube channel.

Perfect as I have a HF aerial here that does exactly the same thing and is used primarily for Amateur Radio. and that is where the principle come from so yep he knows his stuff!!

 

[Hydrostan]

That was a very interesting and helpful video. I have a parabolic and ordered one of his yagi uda antennas.

 

[icecoldgin]

Just thinking aloud.

We are always discussing boosting the signal strength of the RC.

How about boosting the signal strength of the aircraft/drone antenna?

I watched some YTs on boosting the built in antennas of cell phones to get better wifi signals.

Will that work for the AC? Hmmmm ....

 

[ShadowCat]

Just thinking aloud.

We are always discussing boosting the signal strength of the RC.

How about boosting the signal strength of the aircraft/drone antenna?

I watched some YTs on boosting the built in antennas of cell phones to get better wifi signals.

Will that work for the AC? Hmmmm ....

You will be messing with the internal workings of the drone or adding weight thus negating any gains you might have.

 

[scro]

Just thinking aloud.

We are always discussing boosting the signal strength of the RC.

How about boosting the signal strength of the aircraft/drone antenna?

I watched some YTs on boosting the built in antennas of cell phones to get better wifi signals.

Will that work for the AC? Hmmmm ....

All the yagi and parabolic "boosters" work by directing the RC signal into a more concentrated beam rather than sending it out in every direction. You then need to point the RC towards the drone to reap the benefits. There's no actual increase in power output from the RC. You can get signal amplifiers that you plug in to the RC that increase the transmission power, but then you usually also use different antennas as well.

Putting any yagi or parabolic reflectors on the drone will make it more "deaf" to the RC signal in every direction except the direction the reflector/yagi is pointing. Great for if you want to only fly in a straight line away from you (eg flight range competitions) but not so good for general flying around. It would be possible to fit an amplifier to the drone itself but, as @ShadowCat points out, you'd be adding weight to the drone in the form of amplifier, connections, power supply and possibly different antennas, none of which are really desirable in general use.

The antennas on the drone (and in a cell phone) are a slight compromise on the ideal antenna, but mainly due to size/shape/weight restrictions.

 

[ShadowCat]

Yagi's are indeed passive and this is how the antennas works. The radio waves from each element are emitted with a phase delay, so that the individual waves emitted in the forward direction (up) are in phase, while the waves in the reverse direction are out of phase. Therefore, the forward waves add together, (constructive interference) enhancing the power in that direction, while the backward waves partially cancel each other (destructive interference), thereby reducing the power emitted in that direction. At other angles, the power emitted is intermediate between the two extremes

 

[icecoldgin]

Not really thinking of yagi udas or mini parabolics on the drone.

How about something along these lines:

Hmmm, maybe I can tape these on the front legs and see what happens ?

 

[scro]

@ShadowCat Nice animation of a yagi in action. Better than yards of prose

 

[MMPerrish]

Ya know I got a pair of Yagi Udas and I haven’t experienced the same results as everyone else. My connection drops out at closer distances, is overall kinda sketchy, all the while facing the direction I’m supposed to and attempting to use them correctly. Maybe I’m just in a higher interference area.

 

[ShadowCat]

Not really thinking of yagi udas or mini parabolics on the drone.

How about something along these lines:

Hmmm, maybe I can tape these on the front legs and see what happens ?

ouch if you have to take the cover off blood everywhere!!! and no can do on a iPhone or Smart Controller.. Maybe tinfoil?? ? after all its a reflector