Thoughts on Perceived/Real Loss of Signal Range with Firmware Upgrades

CyberdyneSystems · Apr 16, 2017

I mostly read and don't post too often but a thought occurred today reading about the latest firmware upgrades. First off DJI certainly is a very active company in providing upgrades and continuing to advance its product. Both trying to balance customer needs with looming regulations. Anyway, point being there have been lots of firmware upgrades in the last few months an common response is "my range is now worse, route I've flown lots of times with out issue and I'm now getting disconnects with the controller". So we all received out Mavics over the winter months and have seriously been flying the crap out this amazing bit of technology. Lots of us have areas we have flown at repeatedly and favorite test locations and now are finding our range has been reduced; possibly by the firm ware? Well what else might now be different; well I'm thinking trees in the spring with all there newly budding leafs filled with 2.4Ghz signal sucking water. I'm guessing leafless winter trees are much more transparent to wireless signals and long range flights will be easier in the winter vs spring and summer.

Thoughts?

Bunny Too · Apr 16, 2017

A hard crust of snow helps insulate and extend the signal?

Robbyg · Apr 16, 2017

Nothing has changed about where I fly when using .0500 and .0400

With that said its surprising that not one forum member has a spectrum analyzer that can go up to 2.5Ghz. The one I have in my home lab can only go to 1.8Ghz so it's pretty much useless for WiFi. If we had one member with a spectrum analyzer we could remove the power output changes out of the firmware equation with a definitive answer and then move onto the next possibility. Is DJI changing the acceptable SNR of the signal.

IMHO I think that is what they are doing, just upwardly adjusting what constitutes an acceptable signal and ignoring anything below that. It explains why mine went from some small amounts of degradation in video with .400 to the video just making huge break ups for 3-5 seconds under .500 and then nothing, followed by LOS and RTH. Funny part is I cannot get back control even when the craft is 20% closer than the distance when it lost the signal. I don't have that issue with .400 With .400 the signal comes back much quicker and it fades out very slowly when you go too far.

I don't think its imaginary. Companies that design SDR radios can adjust every parameter of them in software. From DJI point of view they are making the craft more reliable. A good analogy would be between AM radio and FM radio. You can receive the signal further with AM but it may break up as you get further. FM works perfectly just up until the point when the signal completely dies while AM at that same distance is still receivable just a bit scratchy.

Rob