DIY_2.4G_Yagi antenna

Disclaimer: I am not a professional in radio frequency, so I am not responsible for any losses that may be caused by this antenna. Please consider the risks by yourself before using it.

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Board thickness: 1.6mm

Solder mask color: According to your own preference, it does not affect the antenna performance.

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Text begins

    By chance, I saw the data of this antenna and wanted to play with it. The gain is 7dbi and the standing wave ratio is 1.3~1.4 . The performance is still very good. However, the size of the original version is a 15x10 (cm) four-layer board, but there are no traces on the middle two layers, and there are many areas without traces on the outer ring. In order to make it free and not waste, the outer ring was cut off. , and for a more cool purpose, the shape is set to the shape of a maple leaf spatula, hoping that it will not affect the performance of the antenna.

       In order to verify the antenna performance, a comparative test was conducted with the original antenna of the Fossil i6: the remote control was located at the window on the 8th floor, and the receiver was held at a position of about 400 meters to test the RSSI. (Flying is prohibited in the imperial capital, and qualified model friends are welcome to fly for testing)

Since the calculation formula of RSSI is not very clear in the A7105 data sheet, we only compare the values ​​here. We will not discuss whether it is true or not. We get the following data (all numbers are rssi in decimal).

The original Fuse antenna is placed vertically, that is, the antenna points to the sky.

Yagi antenna, the antenna is placed vertically and pointed at the test point.

in conclusion

       It can be seen from the comparison that the RSSI of the DIY Yagi antenna is about 10dbm higher than that of the original antenna, and we know that for every 6dbm increase in rssi, the communication distance approximately doubles, so the effect of this antenna is still good, but it is limited by the lack of The specific parameters of the test instrument and antenna are still unknown.

In addition, the connector can use SMA_JE 1.6MM. I am too lazy to change the PCB. You can buy it yourself.