Tinkerboard S with rtl8812au lost packages. Can not get stable video.

[marstears]

Hardware：ASUS Tinkerboard S (rk3288)
Wifi module：ASUS AC56 USB（rtl8812au）
OS：TinkerOS with linux kernal 4.4
Wifi Driver：patched driver v5.6.4.2
Camera: IMX219
Both RX and TX have the same environment and tested indoor.

wifibroadcast.cfg settings for video:

[common]
wifi_channel = 165
tx_sel_delta = 3 
wifi_region = 'GY' 
debug = False
radio_mtu = 1446
mavlink_agg_timeout = 0.1
#wifi_txpower = None
wifi_txpower = 58        # for 8812au

[drone_video]
keypair = 'drone.key'
stats_port = None
stream = 3
fec_k = 8 
fec_n = 12 
peer = 'listen://0.0.0.0:5600' 
bandwidth = 20 
short_gi = False
stbc = 1
ldpc = 0
mcs_index = 1

[gs_video]
keypair = 'gs.key' 
stats_port = 8002 
stream = 3 
fec_k = 8 
fec_n = 12 
peer = 'connect://127.0.0.1:5600' 
bandwidth = 20

TX video:
gst-launch-1.0 rkcamsrc device=/dev/video0 io-mode=4 isp-mode=2A tuning-xml-path=/etc/cam_iq/IMX219.xml ! queue ! video/x-raw,format=NV12,width=1280,height=720,framerate=24/1 ! queue ! mpph264enc ! 'video/x-h264,stream-format=(string)byte-stream' ! rtph264pay ! queue ! udpsink host=127.0.0.1 port=5600 -v

RX video played with QgroundControl.

wfb-cli gs:

ping from tx to rx tunnel lost about 10%-20% packages.

Video trans with test script.

I have perfect video trans with LAN, but because of package lost I can not even see any continuous image through wifibroadcast. I tried to change settings such like wifi_channel, msc_index and bandwidth got no changes. And I have tested 4 same ASUS AC56 wifi modules with exactly same results. Please help me.

[svpcom]

1. Check that your video bitrate < 7mbit/s. Instead of real cam use gst-launch-1.0 videotestsrc ! videoconvert ! video/x-raw,format=NV12,framerate=30/1,width=1280,height=720 ! x264enc bitrate=4000 tune=zerolatency ! rtph264pay config-interval=1 ! udpsink host=127.0.0.1 port=5600
2. Check that no NetworkManager and/or wpa_supplicant are on used wifi adapters.
3. Try other wifi channel

[marstears]

@svpcom
Do I need write both drone_video and gs_video in wifibroadcast.cfg when insert two cards into same board to do the test?

[svpcom]

Yes. You can just use minimal /etc/wifibroadcast.cfg (only add wifi_channel=XXX in section [common]), because default settings in telemetry/conf/master.cfg already contains them.

[marstears]

@svpcom
Hi, I have done your test. Everythin is good when two wifi cards in same tinkerboard. There was no package lost.

But I still can not make it work when two cards on two boards.

[svpcom]

Check what is difference between linux config on these boards. Try to swap sd-cards between boards to check is this problem software or hardware related

[marstears]

@svpcom
Hi, thank you svpcom. I finally make it work! I
I turned off my office wifi router, and then wifibroadcast seems to be working properly. I don't know why because I'm very sure my router use channel 161 and wifibroadcast use channel 165.
This is the screenshot of server gs log over 20 minutes, there still had same package lost but video was stable.

Was it normal? What else can I do for wifibroadcast optimization?