[Photo] 900MHz band directional antenna production

This is a simple and easy to make high-gain directional antenna, the classic Yagi antenna structure, as shown below:

Note: This antenna was invented by the Japanese Yagi, so it is called the Yagi antenna.

In the figure, the linear vibrator is made of Φ10mm aluminum tube, and the folded vibrator is made of aluminum strip with a cross section of 10 × 3mm. Among them, the reflector is 200mm, the director is 130mm, and the vibrator is 150mm.

This antenna is best used between 800-900MHz. The upper limit can be extended to the mobile communication band of the mobile phone. The effect is acceptable. After 970MHz, the gain drops sharply. The lower limit can reach 780MHz, and the gain below 750MHz drops sharply.

The number of directors can be selected according to the actual situation. Although the more the better, the gain will not increase much after too much, but the total length of the antenna will increase a lot. According to the actual measurement, the antenna gain is about 10 dB for the 7 directors, and about 15 dB for the figure.


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