WLAN radio illumination

When faced with a WLAN infrastructure for data transmission, the design of the WLAN network for VoWLAN must be more closely meshed. In doing the planning, the WLAN supply to nearby areas also needs to be considered so that, for example, phone calls can be made in the coffee area. For the roaming to function perfectly and to achieve good voice quality, a supply with at least -70 dBm within a cell must be assured. The radio cells should also overlap by 6-10 dBm. The VoWLAN telephones and the access points should be set to maximum transmit power (20 dBm/100 mW).

List of minimum requirements for the WLAN radio frequency site survey for VoWLAN

With larger buildings, the three available non-overlapping radio channels, (e. g. 1, 6, 11) will need to be assigned more than once. For there to be no restrictions on performance it should be ensured that, within a radio cell on the same channel, there are no access points working that deliver a signal that is stronger than -80 dBm.

Minimum space between two WLAN access points on the same transmit channel

When installing a VoWLAN it is essential to do an Ekahau site survey™ (www.ekahau.de) to plan the building's illumination and to identify the locations for the access points. A site survey™ uses PC-based planning software to inspect the building and calculate comprehensive illumination. It also identifies the best locations for the WLAN access points.

Typical result of a site survey