WiFi signal at home is not strong? It doesn't matter, the wireless router is equipped with a WiFi signal amplifier made with a can, and the signal will be enhanced. Recently, a microblog of "Home-made WiFi signal amplifier for cans" was spread online. Is this self-made signal amplifier reliable? After some verification by the reporter, the cans can theoretically enhance the WiFi signal, but the effect in actual operation is not great.
The online hotspot guide introduces the process of making WiFi signal amplifiers.
To make a WiFi signal amplifier, you need an aluminum can, a pair of scissors, and a wireless router. First, rinse an empty can with water, cut off the bottom of the can, and then cut the top of the can. Keep the can of about 2 cm near the mouth of the can without cutting. Cut the can body in half along the can body directly opposite the can mouth, and expand the aluminum skin into a fan shape. Then turn the aluminum can upside down, use the antenna to pass through the can opening, and use adhesive tape to stick the aluminum can and the router together.
Since it was the first attempt, it took the reporter an hour to complete the production of the WiFi signal amplifier. Under the guidance of professionals, the reporter conducted experiments.
Open a laptop with wireless network function in the living room and download a WiFi signal test software from the Internet. Without sticking the aluminum can and the router together, move the laptop closer to the wireless router also in the living room. The test software shows that the WiFi signal strength varies between -13dBm and -14dBm. dBm is a unit that indicates the strength of the WiFi signal. The values ​​are all negative. The smaller the absolute value, the stronger the WiFi signal strength.
Then came to the bedroom, which is 20 meters away from the wireless router, separated by two walls, and the WiFi signal strength fluctuated up and down at -50dBm. It can be seen that as the distance increases and the walls are blocked, the WiFi signal strength is also weakened.
After obtaining the data in the normal state, the reporter put a WiFi signal amplifier made of a can on the antenna of the wireless router. When the laptop is close to the wireless router, the WiFi signal strength varies between -12dBm and -15dBm. When the laptop is placed in the bedroom, the WiFi signal strength fluctuates around -49dBm. The reporter also tried to adjust the direction of the WiFi signal amplifier's opening. When the opening direction was facing the laptop, the signal strength was -47dBm when the signal strength was the strongest, and the signal was enhanced.
Through experiments, we can find that although the WiFi signal amplifier made of a can can help, the added signal is almost negligible. Why is this?
"In remote areas, many people use cans as antennas to receive TV signals. Using cans as WiFi signal amplifiers, the principle is the same as this." Dr. Fang Peiyu explained. Now, Fang Peiyu is a technology leader of a high-tech enterprise specializing in WiFi phones.
Fang Peiyu said that the inner surface of the cans reflected radio waves, enhancing the antenna's ability to transmit and receive signals. However, this kind of enhancement is directional enhancement, not amplification, that is, the back signal is reflected to the front, so that the open front signal is enhanced, but the back signal is attenuated. This is the same reason as the flashlight mirror. "If made properly, WiFi signal amplifiers made of cans can be directed to increase the signal by 20%."
However, this is only theoretical. "If you want to maximize the signal, it has a relationship with the curved shape of the can surface, the position of the antenna, and the wavelength of the signal. It is difficult for ordinary citizens to master these skills." Fang Peiyu said.
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