One of the suggestions from the 1st "RF in 3D" video was: compare analog with digital video transmission. In this video you will hopefully understand better why DJI (and other digital video transmissions) can look so much better and how they achieve it!
Analog is relativly easy to understand (works like your 1950ties analog TV) although I simplified it: it's not only FM but rather the color part is phased in as well).
Digital on the other hand is quite complex and we need to know a few basic RF principles until we can "understand" the block of radio waves used by DJI and how it works:
DJI HDL (our Caddx Vista/Airunit RF spec):
OFDM, 256QAM? or 64QAM
79.9999ms sync
ASK (amplitude shift keying) + PSK (phase shift keying) = QAMxx
many spikes (64 or 256) on a grid that can transmit data simultaneous...
After all the research I was a bit dissapointed that I couldn't decode the "spikes" myself with the spectran - but either my knowledge isn't sufficient (I'm not an RF engineer), or we don't know the correct modulation parameters, the sync time...
If you want to join my PATREON, please check it out here: https://bit.ly/2ESMtIO
●▬▬▬LINKS▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬▬●
►my "Analog vs. Digital" video: https://youtu.be/tOgS4ME5tBg
►RF in 3D FIRST video (control links): https://youtu.be/1Eagm0EKp0o
QRP: Digital FPV 1: Overview https://youtu.be/oEDt_Kx2gr8
QRP: Digital FPV 2: Modulation https://youtu.be/E8FxdZp_QzU
Bardwell: HDZero vs DJI: https://youtu.be/SmfbMTe80Uc
Aaronia QAM Video: https://www.youtube.com/watch?v=kYrWMjasNrI
https://aaronia.de/spektrumanalysator/spectran-v6-usb-echtzeit/
●▬▬▬EQUIPMENT▬▬▬▬▬▬▬▬▬▬▬▬▬●
my Hangar: http://goo.gl/QNzck
Filmed with: Sony A7c, OBS Studio (to capture desktop)
Edited with Premiere Pro
●▬▬▬VIDEO INDEX▬▬▬▬▬▬▬▬▬▬▬▬●
00:00 Intro
01:14 Analog video
02:12 DJI Digital Video
06:22 QAM number = BITRATE!
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#DJIFPV #digital #SpectranV6
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