Summary of Wireless Interference avoidance and reduction methods

Method to avoid and reduce Wireless Interference 1.RRM

RRM isWLANThe spectrum resource management module of the Network monitors and analyzes Air Port noise, WLAN interference outside the network, air port utilization, and traffic interaction between the AP and Client, the AP channel is dynamically adjusted based on the information and the optimal channel is selected for transmission. Channel adjustment must be considered for the whole network, and the impact on the Client must be minimized. As shown in figure 6, the target office area to be covered has two AP networks working on Channel 11 and Channel 6, respectively. Then, RRM can scan the result based on the empty port, automatically adjusts the AP adjacent to the AP to other non-interference channels.

On the other hand, RRM can monitor the neighbor information of each AP in the network and the RF information of the Client, and dynamically adjust the sending power of each AP according to the information. When black hole coverage is detected, the transmission power will be increased. When the signal strength of the neighboring AP in the same channel is higher than a certain degree, the transmission power will be reduced and mutual interference will be reduced. 7 ).

Method for avoiding and reducing Wireless Interference 2. Spectrum Analysis

Spectrum Analysis can detect non-WLAN interference from the surrounding environment in a timely and comprehensive manner. When new interference is detected in the spectrum analysis, an alarm will be triggered, and information such as the interference type, channel, interference intensity, and duty cycle will be displayed, and the interference location can be further located, facilitate timely troubleshooting. Spectrum analysis can also monitor the performance of the entire network's blank ports and issue alerts in a timely manner.

The combination of spectrum analysis and RRM enables the entire network to avoid interference channels in a timely manner without human intervention, thus ensuring network availability.

Methods for avoiding and reducing Wireless Interference 3. Channel multiplexing

In a high-density deployment environment, such as a spacious conference hall, student dormitory, and library, the AP deployment density is relatively high, which usually leads to visibility between the AP in the same channel and serious mutual interference. By using channel multiplexing technology, the AP coverage can be further reduced to eliminate mutual interference and improve the degree of channel reuse.

Channel multiplexing actually increases the AP's CCA threshold and reduces the reception sensitivity. CCA, that is, channel idle evaluation, means that the WLAN Chip needs to evaluate whether the channel is idle before transmitting signals to the blank port. If it is idle, messages can be sent after the conflicting backoff algorithm is executed. If it is busy, you need to wait. The receiving sensitivity means that the RF signal strength that reaches the WLAN receiver must not be lower than a certain value before it can be correctly received. In fact, when the RF signal strength is lower than the receiving sensitivity, the WLAN Chip will not start the receiving action.

When the receiving sensitivity is reduced, the AP coverage is reduced, but the neighboring AP signals of the same channel can be ignored without affecting the reception in their respective ranges. When the CCA gate is increased, even if the neighboring AP of the same channel sends a signal, as long as the signal strength does not exceed the CCA threshold, the AP can still send its own signal. At this time, as long as the signal reaches the Client to meet the SNR requirement, it can still be correctly received by the Client.

Methods for avoiding and reducing Wireless Interference 4. network deployment survey and Optimization

In the Wireless Interference avoidance and reduction method, the spectrum navigation method requires the survey and deployment environment, attenuation coefficient of various obstacles, network application service planning, AP coverage planning, select the AP installation location, select the appropriate transmitting antenna, and so on. Without good network deployment, it is difficult to achieve the best network performance.

Methods for avoiding and reducing Wireless Interference 5. Spectrum navigation

In the method of avoiding and reducing Wireless Interference, the method of spectrum navigation is to guide dual-band users to 5g frequencies as much as possible to reduce the load on 2G. The number of non-WLAN devices on 5G is relatively small, and the number of channels is large, which can achieve very good performance.