Wi-Fi is a wireless local area network, which is a wireless local area network technology based on the IEEE 802.11 standard.
WiFi frequency band
WIFI is divided into 2.4Ghz and 5Ghz in frequency band.
The working protocol of the 2.4Ghz frequency band is 802.11n, and the maximum air interface rate of the dual antenna (physical layer theory) is 150 2=300Mbps (300 Mbit/s).
The working protocol of the 5Ghz frequency band is 802.11ac, and the common dual antenna maximum air interface rate is 433.3 2=867Mbps.
WiFi rate measurement
WiFi is divided into two types according to the rate, one is the air interface rate, and the other is the actual speed measurement.
Speedtest website speedtest access method
Air interface speed
air interface speed measurement cannot represent the actual speed measurement value. In practical applications, we often find that the WiFi speed is lower than the air interface speed because WiFi signals are transmitted through radio waves. When wireless signals are transmitted in the air, interference and Loss, these factors will affect the actual rate of WiFi.
Actual speed measurement The
actual speed measurement is similar to a driving car. For example, the maximum speed of the car dashboard can reach 300km/h, but it is limited by road conditions (equivalent to Wi-Fi interference), car damage (similar to Wi-Fi loss), Speed limit signs (similar to network bandwidth restrictions) and other factors, our actual driving speed basically cannot reach the maximum speed. Therefore, the actual speed measurement value of WiFi is often lower than the air interface speed.
The normal Wi-Fi speed measurement value is
in an ideal environment (a shielded room without interference). The WiFi speed measurement experience data of domestic mainstream ONTs refers to the values in the table. In an open interference environment, the WiFi speed measurement value will decrease. If the interference is small , 2.4GWiFi speed measurement experience value is generally about 50Mbps, 5G speed measurement value varies greatly according to the device capacity, the speed measurement experience value using Mac pro is generally about 500Mbps, if the actual WiFi speed measurement value is far from the above experience value, then the network needs to be Trouble shooting.
WIFI troubleshooting speed test
1. Speed measurement with wired
Use wired for speed measurement. If the wired speed measurement is much lower than the operator's contracted speed, such as the operator provides 100M broadband, the actual speed is only 50M, it means that there is a problem with the network, and the network fault needs to be checked. If the wired network speed is normal, the WiFi speed measurement is lower If the wire rate difference is large, perform the second step.
2. Speed measurement close to WiFi devices
Perform speed measurement close to the ONT device. When measuring speed, it is recommended that the client device face the ONT with a distance of about 0.5~1m and no obstructions.
Third, the configuration is correct
3. Confirm whether the configuration is correct. Unreasonable configuration will affect the WiFi speed measurement. Check whether the WiFi speed is low due to improper WiFi configuration.
4. Whether the test time period is optimal
4. Whether the test time is the best, avoid the peak period of Internet access, during this period mutual interference between WiFi affects the speed measurement performance, it is recommended to conduct speed measurement in multiple time periods.
5. Whether the test environment has less interference
Keep away from other interference sources when testing, for example, choose a separate small room for testing, or use tin foil to build a simple shielded environment, put the device in, and test.
6. Whether there are other software influences on the test equipment
Different devices have different WiFi performance. Try to close the software on the device that may affect the network tester, such as firewall, anti-virus software, WiFi scanning software inSSIDer, etc., and then test the speed.
7. Only the test device is connected to WiFi during the confirmation test
Disconnect other users during the test to ensure that only the test device is connected to WiFi. You can see the number of connections in the STA information of the network device, and test after removing other connected users.
8. Capability of testing and testing equipment
The speed measurement equipment must be greater than the expected speed measurement. Generally, equipment with strong WiFi capabilities is used for speed measurement. Avoid poor speed measurement due to insufficient speed measurement equipment.
Improve WiFi signal
There are many ways to improve the WiFi signal. It is necessary to keep the device away from objects that affect the WiFi range and signal strength so that it can give full play to the signal.
- Objects that cause signal attenuation: metal objects, load-bearing walls, large appliances/furniture.
- Objects that cause signal interference are mainly electronic devices: microwave ovens, wireless phones, Bluetooth devices, etc.
- Regarding the placement of the equipment: we can also adjust the antenna direction to expand the coverage of the WiFi signal. For a single floor, the signal and the antenna have a longer propagation distance in the vertical direction. The antenna should be placed vertically to expand the horizontal coverage. For multiple floors, both horizontal and vertical signal propagation should be considered.
- If you have higher requirements for network speed, watching wireless videos, online games, etc., it is recommended to use a wired connection.
If there is only one router in the home, it is recommended to put it in the middle, with the antenna upright. For duplex floors, it is recommended to add a Repeater to ensure wider WiFi coverage.
Wireless stuck troubleshooting guide
More than 75% of users choose mobile phones to watch online videos wirelessly. Therefore, the quality of the wireless network is very important, and the contracted broadband and WiFi quality between users and operators are the two key factors affecting wireless video bandwidth.
Therefore, when the wireless video is stuck, it is necessary to investigate from these two aspects.
1 Confirm whether the service meets the video requirements
2. Check whether the wired playback is stuck
3. Confirm whether the terminal equipment signal is normal
Wireless troubleshooting
1. Understand the network diagram of the wireless network and the necessary conditions for network fault location. The wireless network is divided into three layers from top to bottom, the convergence layer, the transmission layer, and the access layer. Failure in any link will affect the network efficiency. When a network fails, the troubleshooting principle is: check the hardware, upper-layer software, and lower-layer software, with the upper layer first, then the lower layer, and the hardware then software segmented troubleshooting strategy. The troubleshooting idea is divided into three steps:
1. Check whether there is packet loss or forwarding abnormality in upper-level equipment, such as transmission network, gateway, etc.
2. Check the optical modem device, the power adapter is not matched, and the optical path quality problem.
3. Check the mobile device, such as Compatibility, equipment failure, etc.