What is Adaptive-Link?

Adaptive-Link is a system that automatically adjusts video and link quality between the drone and the ground station based on signal strength.

When you are close — video is clear and smooth. When far away — quality decreases, but the link remains stable.

Info

In other words, you no longer need to manually set transmit power!

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How It Works

Adaptive-Link automatically controls:

• Bitrate
• Transmitter power
• MCS, SNR, RSSI parameters
• FEC and QoS depending on distance and conditions

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Installing Adaptive-Link on Radxa GS

1. Image v1.9.9 or newer → disable Wi-Fi card power.
2. Reboot Radxa and log in as radxa/radxa or root/root.
3. Run nmtui — connect to your home Wi-Fi.
4. SSH → run:

sudo curl -L -o alink_install.sh https://raw.githubusercontent.com/OpenIPC/adaptive-link/refs/heads/main/alink_install.sh
sudo chmod +x alink_install.sh
sudo ./alink_install.sh gs remove
sudo ./alink_install.sh gs install

Wait for the update to finish. Reboot the VRX.

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Installing Adaptive-Link on Runcam WiFiLink V1/V2 Cameras

1. Download Multiconfigurator.
2. Extract and launch it.
3. Connect to the camera at 192.168.1.10 (password 12345).
4. Click Connect (turns blue when camera is reachable); after connecting the camera type, sensor and Wi-Fi card are detected.
5. Go to Firmware → Runcam → Wifilink → fpv and click Update.
6. After the update:
   Open Telemetry → enable UART0, add Mavlink.
   Enable Alink Drone → Enable.

After the camera connects to the Radxa you should see this window:

Warning!

If it doesn't appear — adaptive_link is NOT working.

Edit the configuration file on the Air Unit — only a few values matter:

/etc/alink.conf

Here you set whether RSSI or SNR takes priority:

snr
rssi_weight=0,5
snr_weight=0,5
osd_level=5

osd_level controls how many lines of info Adaptive-Link displays (bitrate, CPU load, etc.) — range 0–5.

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Force-Enabling Adaptive Link

1. Open WinSCP.
2. Connect to the camera via FTP/SSH.
3. Open /etc/rc.local and insert before exit:

alink_drone &

4. To overclock the CPU (optional): open /etc/rc.local and add:

echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
echo 1200000 > /sys/devices/system/cpu/cpu0/cpufreq/policy0/scaling_min_freq
echo 1200000 > /sys/devices/system/cpu/cpu0/cpufreq/policy0/scaling_max_freq

Note!

Warning: some cameras may behave unstably with overclocking — test on the bench first!

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Safe TX Profiles

txprofile files for network cards — here (filename must always be txprofile.conf)

Example safe TX profile:

# <range> <gi> <mcs> <fecK> <fecN> <bitrate> <gop> <Pwr> <roiQP> <bandwidth> <qpDelta>
999 - 999   long 0 8 12 1999 10 30 0,0,0,0 20 -12
1000 - 1050 long 0 8 12 2000 10 30 0,0,0,0 20 -12
1051 - 1500 long 1 8 12 4000 10 25 0,0,0,0 20 -12
1501 - 1950 long 2 8 12 8000 10 20 12,6,6,12 20 -12
1951 - 2001 short 2 8 12 9000 10 20 12,6,6,12 20 -12

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TX File Parameters

• range — range for adaptive transmission.
• gi — guard interval.
• mcs — modulation and coding scheme.
• fecK — number of data symbols in FEC.
• fecN — total number of symbols in FEC.
• bitrate — data transmission rate (bits/s).
• gop — keyframe interval.
• Pwr — transmitter power level.
• roiQP — quantisation for region of interest.
• bandwidth — channel bandwidth.
• qpDelta — corrective QP difference.

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