One of the ways to extend the range of the WiFi network is by increasing the AP power. In this article you can read about the signal power of the access point and wireless router.

AP Power and Wireless Range Extension

Common Misunderstanding About the Signal Power in the Wireless Networks

The common belief is that the range of the wireless network depends strictly on the signal power of the access point. In the reality, the factor which you could instantly connect with a wireless network range is SNR – signal-to-noise ratio. SNR is the ratio of the signal power to the noise power.

SNR and Access Point Performance

The higher SNR, the better the performance of the access point. The AP power could be irrelevant. You can have the same signal power, but you can reduce the noise. This will result in better performance and increased range.

AP power

AP power

When You Lose the Wireless Signal?

Background noise is present everywhere with the constant average intensity. As the wireless clients move from the AP, signal power decreases while the background noise is constant. This results with decreased SNR and lower speed. You can see in the image red dotted line of the background noise. When the received power is less than background noise, you lose the wireless signal. In the real world, there are also the obstacles and other wireless signals. When the AP power is less than the power of other wireless signals, the client loses the signal. This happens in particular distance from access point. The factors which determine the power of other wireless signals are:

  • Background noise – constant
  • Other wireless signals
  • Physical obstacles
Low rate clients downgrade the WiFi performace

Low rate clients downgrade the WiFi performace

Low Rate Clients Downgrade the WiFi Performance

In this picture is an example of 802.11n WiFi cell. The region with lower data rates,  takes the most space of the coverage. The clients in this boundary region are forced to use lower speeds. AP for lower speeds needs to use the lower modulation schemes. All these results with inefficient use of AP capacity. Approximately 85% of the network coverage is in the three lower rate regions.

Site Survey for the Enterprise Wireless Network – Speed v’s Range

Proper wireless site survey is crucial for big enterprise wireless networks. So if you want to have a bigger range of the wireless network you need to increase the AP power. This will result with a downgrade in performance and lower speeds. If you have more AP, configured with the lower power, you will have better performance and bigger data rates. More AP gives the more cost. You need to obtain the optimum between the AP power on each AP and the number of APs.

Design and implementation of WiFi network for Wireless IP telephony is quite demanding task. Not only because capacity and coverage but also many other factors. Read more about wireless IP telephony in Wireless IP Telephony – Voice over WLAN (VoWLAN).

Home Wireless Network Site Setup

In the home environment, wireless network range is not big and there is limited number of clients. The biggest problems here are:

  • Physical obstacles
  • Other wireless signals

You don’t have to bother with the speed vs range optimization of the. With two things you can dramatically increase the performance of the home wireless network:

  • The optimum AP placement
  • Increase the AP power

The Optimum AP Placement

Place the AP or wireless router in the central location, away from the obstacles like walls and metal objects. The AP should be also away from other wireless signals. Devices like microwave ovens, cordless telephones and baby monitors interfere with the AP signal. Put the AP at least 1m (3 feet) from these devices.

Increase the AP power

If the result of the poor WiFi connection is some physical obstruction or other wireless signal, increasing the AP power could dramatically increase your wireless network performance. The problem is that most of the home wireless routers don’t give you the possibility for adjustment of the AP power. The AP power can be increased in the following ways:

  • Firmware upgrade
  • New AP
  • Improving the antenna

Read the great article about this on Increasing a Router’s Transmit Power. More about improving the wireless antenna read The Best WiFi Antenna. About the other ways to extend the range of the wireless network you can read on WLAN Extend.

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