ESP8266 Developer ZoneThe Official ESP8266 Forum2015-12-14T10:26:07+08:00https://bbs.espressif.com:443/feed.php?f=6&t=14482015-12-14T10:26:07+08:002015-12-14T10:26:07+08:00https://bbs.espressif.com:443/viewtopic.php?t=1448&p=5025#p5025 You can refer to PCB antenna of ESP-WROOM-02 Module that can be obtained in the following link.