With the widespread adoption of wireless networks, especially in residential buildings where numerous wireless signals coexist, mutual interference has severely impacted network stability and transmission speed. To address this issue, let’s analyze how to prevent interference and achieve the most stable wireless network environment.
1. The detection and mitigation of wireless interference can be performed either by scanning with the APs providing access services, or through networks composed of specialized equipment. It can even involve dedicated handheld RF devices for interference location, which is generally suitable for small networks or precise positioning within limited areas. For large networks, a dedicated monitoring network typically needs to be deployed. The devices in such specialized networks are generally APs in Monitor mode or dedicated Sensors.
2. One approach is the independent mode, where the devices for detection and the devices for network access are managed by different controllers, with no interaction between the two;
The other is the integrated mode, where the devices for detection and the devices for network access are managed by the same controller. The detection network server can also process monitoring data from the access network’s APs. Compared to the independent mode, integrated networks offer unified management, full utilization of access network resources, and more convenient detection and location capabilities.
3. When the air interface signal energy exceeds a certain threshold, an FFT transformation is performed, and the output is further fed to the WLAN receiver and various identifiers. The former determines whether the interference is a WLAN signal and further analyzes the MAC information, while the latter identifies the type of non-WLAN interference source.
4. Wireless interference avoidance and mitigation can bring significant performance improvements to WLAN networks. These technical features have been widely implemented across the industry. By refining details such as 802.11 packet transmission or overall WLAN coordination, the entire network is enhanced, mutual interference is reduced, and WLAN network performance is notably improved. These technical features include: packet transmission rate adjustment; per-packet power control; and intelligent load balancing technology.
1. Packet transmission rate adjustment involves dynamically calculating the transmission rate for each packet. For each packet sent or retransmitted to a Client, factors such as the Client’s signal strength and historical transmission data are considered to dynamically calculate the appropriate current transmission rate.
2. When a transmission fails, different rate adjustment algorithms can be used based on the environment. In high-density environments, packet transmission failures are typically caused by packet collisions. Using a very low transmission rate only increases the air time of packet transmission, affecting a larger area and leading to a higher probability of further collisions. This may cause other APs to further reduce their transmission rates, plunging the entire network into a low-performance state. By using only high-rate retransmissions, even if multiple attempts are unsuccessful, upper-layer retransmission mechanisms can be leveraged, ultimately not affecting application availability.
3