How do I design an antenna

Forum: Microcontrollers and Digital Electronics BTM222 PCB antenna design





Moin, I'm currently designing a board for a BTM222 module. I didn't have that much to do with antennas, though. My antenna on the board (the entire signal) is now exactly 31mm long (according to the Eagle ULP "lenght-freq-ri") and 1mm wide (for the most part). Do you think that dignity is enough? There are also no huge distances to be bridged via Bluetooth (max 1.5m; only about a connection to the smartphone). Moritz



you have to leave space around your antenna (no gnd or cables / components) that it is kinked is also suboptimal, but at <5m it="" doesn't="">

: Edited by user


OK. Would it be better that way? Or also copper around it and just no GND?



With my BTMs, I always put a straight conductor with a lambda / 4 length and rounded for the feed 5mm away next to the module, conductor track width 0.5mm. The ground plane ended at the module pins so that the antenna only rested on the bare FR4. The whole construct is placed on the edge of the board. That always worked very well.

: Edited by user


What do you think of such an antenna? Do you think that would be better than the first? Moritz



Yes, it's better. But the exemption can be a little bigger. Move the antenna closer to the edge of the board.

: Edited by user


Hello, it was a couple of years ago, but: Did the antenna work so well after all? Greetings Lucas

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