- An often overlooked component in WLAN design during coverage analysis is the use of semidirectional antennas.
- Many deployments of WLANs use only the manufacturer’s default low-gain
omnidirectional antenna, which typically has about 2.14 dBi of gain.
- Buildings come in many shapes and sizes and often have long corridors or hallways where the coverage of an indoor semidirectionalantenna may be much more advantageous. Many warehouse devices still use legacy non-802.11n technology, which is more susceptible to problems caused by multipath. Using a unidirectional antenna i areas where there are metal racks, file cabinets, and metal lockers can
be advantageous at times because you can cut down on reflections.
- With 802.11n and 802.11ac technology, semidirectional MIMO patch antennas are often pointed down from the ceiling to provide for sectors of coverage in areas where there is a high density of users and devices.
- A good site survey kit should have a variety of antennas, both omnidirectional and semidirectional. Do not be afraid to provide coverage in a building by using a combination of both low-gain omnidirectional antennas and indoor semidirectional antennas