How many access points can I co-locate within the same coverage area?
The number of access points that can be co-located within the same coverage area also depends upon the version of 802.11 being used. With 802.11b and .11g, there are 11 separate channels that an access point can be configured to use, but only three of those channels are non-overlapping, allowing only three access points to be within a common coverage area without interference. If there are other access points within a given radio space running on overlapping channels, user performance will deteriorate noticeably. 802.11a provides for 12 non-overlapping channels, allowing a greater deployment of access points. However, not as many client devices support 802.11a.
What is the range of a typical Wi-Fi access point?
The range of a Wi-Fi access point depends on the specific hardware being used. Factors that determine a particular Wireless Access Point’s (WAP’s) range are:
- the specific 802.11 protocol employed
- the overall strength of the device transmitter
- the nature of obstructions and interference in the surrounding area
A general rule of thumb in home networking says that 802.11b and 802.11g WAPs support a range of up to 150 feet (46 m) indoors and 300 feet (92 m) outdoors. Another rule of thumb holds that the effective range of 802.11a is approximately one-third that of 802.11b/g. Both of these rough estimates fall on the high end of the range seen in practice.
At UNC, we’re designing a pervasive Wi-Fi infrastructure based on approximately 1500 sq ft per access point, based on 802.11a requirements.