Adding an external wifi antenna to Autopi CM4

Projects / Brainstorming
#1

Hi all, wanted to share how I added an external wifi antenna (connector) to the Autopi. It looks like this and should improve wifi reception when installed in/near metal.

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Selected photo (3)2000×1500 175 KB

First machine this part with 4 holes

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Then reinstall the 3 uFL to SMA connectors. Install 1 more for the CM4 wifi port. These are commonly available on adafruit or amazon.

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Finally switch to the external connector in your config.txt :

dtparam=ant2

2 Likes
#2

Signal levels with a generic 8dBi antenna,

Before

wlan0     IEEE 802.11  ESSID:
          Mode:Managed  Frequency:2.462 GHz  Access Point: 
          Bit Rate=72.2 Mb/s   Tx-Power=31 dBm   
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Power Management:on
          Link Quality=42/70  Signal level=-68 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:476  Invalid misc:0   Missed beacon:0

After

wlan0     IEEE 802.11  ESSID:
          Mode:Managed  Frequency:2.462 GHz  Access Point:   
          Bit Rate=72.2 Mb/s   Tx-Power=31 dBm   
          Retry short limit:7   RTS thr:off   Fragment thr:off
          Power Management:on
          Link Quality=52/70  Signal level=-58 dBm  
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0