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by FrankPetrilli 839 days ago
Unfortunately the latency is nowhere near good enough for racing - best case actual results are ~100ms E2E. The project authors have claimed some absurdly low latency numbers in the past but they're laden with asterisks, like using a wired connection.
1 comments

The latency numbers were indeed shady .. like he advertised "cheapest digital fpv" and for that price they were doing 720p60fps with the latency around 80-100 indeed.. but with the more expensive 120fps setup, they were getting closer to interesting latency: https://youtu.be/i_Wz9oAK5z4?t=224

The other issue is that a lot of their source code isn't open source yet. The majestic etc.. bits.

What I am hopeful is that: once there is easy to use hardware for people to tinker around with, the project will actually improve to the point of being a real system like ExpressLRS.

DJI/Caddx are using basically LTE radios, I doubt WiFi chipsets will have acceptable perf. Still, for fixed wing this might be acceptable and cheaper than existing systems. For freestyle/racing.. forget it.
Typically speaking, even if you are getting around 10-12Mbps over wifi that means each 720p raw frame takes only ~2-3ms to transmit. Most of the time is spent in encoding and decoding the video frames, waiting for retransmissions etc..

Also they aren't exactly using Wifi. They're using just the chipset to broadcast. Here's the interesting talk from the original author of wifibroadcast . The challenges they fixed to use wifi hardware for transmission: https://media.ccc.de/v/36c3-10630-wifibroadcast .