High-power wireless bridges Almost every home has a wireless router. The quality of wireless signals can even affect people's moods, and even indirectly affect the family. Installing cans, placing routers on high ground, buying wireless routers with “Walling the Wall†propaganda... Various methods show that everyone suffers from poor wireless signal in the home. Many friends have thought about making a fuss about the antenna of their own wireless routers. What exactly does the antenna have to do with the quality of wireless signals?
What exactly affects the wireless router's signal
In reality, the interior of a home is mostly a brick wall and a cement wall. It has a great effect on the attenuation of wireless signals, and often has problems with poor signals. It is very troublesome. As a result, some consumers have purchased a foreign brand wireless router that looks very tall, but found that the wireless signal has not improved or even weakened. This is because the domestic and foreign use environments are different. Most of the foreign houses are wooden structures. The degree of attenuation of wireless network signals is not so high. Therefore, some foreign brands of wireless routers have not performed so well in China.
Many wireless antenna routers are popular
As a result, consumers turned to many wireless routers to initiate "offensives." Imagine holding a wireless router like these Octopus. When you go home and power on, you can let the signal cover every corner of the room. However, the strength of the display is cruel wireless signal is not determined by the number of antennas. Because the wireless signal transmitted by the wireless router belongs to the radio frequency signal, the country has strict standards for the transmission power of the wireless router. The national regulations stipulate that the transmission power of wireless routers should not exceed 100mW, which is 20dBm (2.4GHz band). Under the condition that the transmission power is fixed, the signal transmission algorithm will be tested. This is the embodiment of the strength of the manufacturers.
Beamforming technology
In addition, nowadays we can often see “beamforming†beamforming technology on high-end wireless routers. Beamforming is a technique that allows the wireless router's transmitter to perform directional transmission based on the location of the receiver. If beamforming routers are to be used, Must have multiple antennas. This technology transmits over multiple paths. At the receiving end, a certain algorithm is used to process the signals received by multiple antennas, which significantly improves the SNR at the receiving end, so that even if the receiving end is far from the transmitting end, It also gets good signal strength.
These devices can cause co-channel interference problems
Finally, there is the issue of interference at the same frequency. I believe many of my friends are using wireless mice, wireless headphones, wireless controllers, and wireless keyboards. In fact, these wireless devices work in the 2.4 GHz band, and the signals transmitted by our wireless routers will cause co-channel interference. There is also a microwave oven in the kitchen that can cause serious interference to the 2.4 GHz band during work. To avoid this interference, we should try our best to choose a 5Ghz band network. Now the basic mainstream devices already support the 5GHz band, but the wall is the weakness of the 5GHz band.
So, what kind of method can we use to improve the wireless router's signal?
Does adjusting the wireless antenna direction really improve the signal?
To mention the antennas on the wireless router, we have to start with the principle of wireless antennas. I often see words such as "3dBi" and "5dBi" in the parameters of wireless routers, which represent the gain of the antenna. The antenna gain plays a role in amplifying the wireless signal transmitted by the wireless router and is closely related to the direction of the wireless signal transmission. Even in theory, it can be said that the higher the gain of the wireless antenna, the farther the coverage of the wireless signal becomes.
Wireless antenna gain schematic
In daily life, our common wireless router antenna gains are generally 3dBi and 5dBi, and some of the products with prominent wall penetration capabilities use 7dBi gain wireless antennas. In simple terms, when the transmit power is the same, the wireless signal transmitted by the 3dBi booster antenna is shaped like “()â€, much like a semicircle. The 5dBi antenna, which emits a signal similar to "<>", is more like a flattened oval. From the figure we see that the higher the gain is, the smaller the vertical angle is, and the relationship between the coverage area and the shielding angle can be clearly seen. Therefore, if used within a certain range, the gain of 3-5 dBi is beneficial to signal reception, and it is a wrong understanding to increase the antenna once it is thought that it will bring better results.
The antenna is placed horizontally?
Nowadays, there is a small technique for improving wireless signals on the Internet. Users place an antenna of a wireless router horizontally and place it vertically, which can increase the strength of wireless signals. It was very reasonable to hear it, but also people think of directional antennas. A directional antenna has the ability to transmit and receive wireless signals in a certain direction very strongly, and the reception and transmission capabilities in other directions are basically zero. In general, such an antenna looks very much like a small radar or "fence" and can have the ability to receive signals up to several tens of kilometers.
Or all directions?
The wireless routers in our homes generally use omni-directional antennas that can transmit wireless signals evenly to 360° without directivity. According to the principle of a wireless antenna, a horizontal antenna and a vertical antenna form a three-dimensional signal coverage network to increase the strength of wireless signals. Next, we will actually test this little trick in the ZOL office area to see if the wireless antenna is placed sideways.
Wireless antenna is displayed horizontally and vertically to maximize its power
We will conduct two sets of comparison tests in ZOL's office area. One set is to test the wireless signal strength when the antenna is upright; the other set is to place one antenna vertically and one antenna is facing horizontally. Place the direction of the mobile device for wireless signal strength testing. After the test is over, the two groups of wireless signal strengths are compared to see which group of wireless signals are more powerful. (Note: The test results are for reference only)
test environment:
Point B is the placement point of the wireless router; Point A is the test point for the strength of the wireless signal. It is about 30m away from point A and there is no barrier between point A and point A.
Wireless signal strength in antenna vertical state:
Antenna vertical placement
Wireless signal strength is 85%
Wireless signal strength in a horizontal and vertical state:
The antenna is placed vertically and horizontally
Wireless signal strength is 89%
After a comparison test at the same test point, we can see that the wireless signal strength of all antennas placed vertically is 85%; the wireless signal strength of the antenna placed vertically and horizontally is 89%. The professional wireless signal test software proved the way of placing the antenna vertically and horizontally. At point A, it has stronger wireless signal strength. We can completely adjust the antenna of the wireless router to a horizontal and vertical state at home. The vertical antenna is responsible for providing omnidirectional wireless signals, and the vertical antenna is responsible for pointing the multiple areas of mobile devices to enhance wireless signals for them.
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