Find out the "culprit" of wireless network Interference"

Wireless Network interference can cause a lot of troubles. Why is the network speed so slow because few people use wireless Internet access? That's because some RF Frequencies you don't see are "cool ". After reading the following sections, you will learn about the causes of interference in the wireless network.

RF interference may cause catastrophic deployment of Wireless LAN (WLAN. However, many companies are still able to use their wireless networks without any trouble. However, after installing wireless networks, however, the network cannot run as planned. Interference signals from external RF Sources are often the culprit. Therefore, it is necessary for us to understand the impact of RF interference and technologies to avoid interference.

Do not complain about the slow network. RF interference is the culprit.

To understand that wireless network interference is related to RF interference, you can quickly view how the 802.11 station (customer's wireless communication devices and Access Points) accesses the wireless media. Data packets can be transmitted only when 802.11 stations do not transmit data on other stations. If another station happens to be sending data packets, the other station will wait until the media is idle. The true 802.11 Media Access Protocol is more complex, but this understanding makes it easier for us to analyze the problem.

RF interference includes unwanted radio frequency signals, which interrupt normal wireless operations. Due to the characteristics of the 802.11 media access protocol, the RF signal reaches a certain amplitude and frequency, it looks like a data packet sent by 802.11 stations. Of course this is a false signal. Before the interference signal disappears, this fake signal will cause 802.11 stations to wait for Uncertain Time before trying to access the media.

Even worse, RF interference does not comply with the 802.11 protocol. Therefore, when a valid 802.11-bit stand sends data packets, the interference signal may suddenly start to make waves. In this case, the target station will receive the wrong data packet and cannot use the "OK" signal to respond to the source station. On the other hand, the source station will try to resend data packets. Wireless Network interference will cause unnecessary waste of money for enterprises, which is also a headache.

This may cause wireless network interference, which may lead to network latency and user dissatisfaction. Sometimes, when rf interference exists, the 802.11 Protocol automatically switches to a lower data rate (which also reduces the use of wireless applications) and tries to continue running. The worst case is that 802.11 stations will wait until the interference signal disappears, and the delay can be several hours or even longer.

What are RF interference sources?

For a 24. GHz wireless network, the interference signal sources include microwave oven, mobile phone, Bluetooth-enabled devices, frequency-hopping spread spectrum wireless networks, and adjacent wireless networks. Among them, the most destructive is the 24. GHz mobile phones and cordless phones widely used at home and in the unit. If someone is using this phone in a wireless network room (such as 802.11b or 802.11g in the 24. GHz band), the performance of the wireless network will be greatly reduced.

Microwave ovens that are about 3 meters away from the AP will also lead to a reduction in the performance of the wireless network (802.11b/g. Of course, this refers to a working microwave oven. If someone is operating Bluetooth-enabled devices, such as laptops and PDAs, very close to the 802.11 station, especially if the 802.11 station is far away from the station that is communicating with it (that is, the signal is very weak), it will also cause serious performance degradation. Although there are few frequency-hopping spread spectrum wireless networks, if they exist, the performance will be greatly reduced. Networks like wireless networks adjacent to your wireless network may conflict if you do not coordinate the frequency selection with the other party.

Take measures to avoid RF interference

Unless you are a "Superman", you cannot directly view or eliminate RF interference in wireless network interference. Of course, when using the network, you may find problems, such as the slow speed of surfing the Internet.

The following are some tips for you to consider using these methods to reduce the RF interference of your network:

1. analyze the possibility of RF interference

You may need to do this before installing the wireless network. You may wish to analyze the problem through the RF field investigation. In addition, you need to talk to personnel in the facility to learn about other RF devices that may be in use. This will give you some information and help you decide what actions you need to take to reduce interference.

2. prevent interference sources from running

After knowing the potential RF interference source, you can turn it off to clear the interference. This is the best way to deal with RF conflicts. However, this method is not always practical. For example, you cannot stop people next door from using their mobile phones. However, in the company's user location, you can turn off Bluetooth-enabled devices and microwave oven operations.

3. Provide adequate wireless network coverage

To avoid wireless network interference, one way to reduce RF conflicts is to ensure that the wireless network has a strong signal through the location of its users. If the signal gets weaker, the interference signal will naturally become more troublesome. This is like you are talking to someone, and there is a plane flying over, in order to let the other party hear, you can only speak a little louder. Of course, this also means that you conduct a thorough investigation on the site to determine the optimal number and location of the AP.

4. Correctly configure Parameters

If you are deploying an 802.11g network, adjust the AP frequency so that it can avoid the frequency of potential interference signals. However, this method is not always effective, but it is worth a try. For example, a microwave oven usually has a conflict with the top 2-4 GHz bandwidth. Therefore, you may need to adjust the AP close to the microwave oven so that it only uses 1 or 6 channels instead of 11 channels.

5. Deploy a 5 GHz Wireless Network

Most of today's RF interference is in the 2-4 GHz band. If you find that the other technologies we mentioned earlier do not play a major role in preventing interference, you may wish to consider deploying an 802.11a or 802.11n network. In this way, in addition to preventing RF interference, you can also make the network have a higher throughput.

One problem with RF interference is that it will change over time. For example, a neighbor just buys a cordless phone and uses it frequently, or the use of wireless networks in your region is greatly increased. This means that the impact of RF interference will increase over time, and of course it may also disappear. Therefore, you can also investigate potential RF interference in advance.

To make your network smoother, pay close attention to the wireless devices that may cause lower performance of the wireless network.