Cisco Aironet 2.4GHz Diversity Patch Antenna, AIR-ANT2012
The Cisco Aironet AIR-ANT2012 is a 2.4GHz, 6.5dBi diversity patch antenna which is compatible with Cisco Aironet 1200 and 1240 series wireless access points. To determine if the AIR-ANT2012 is the correct component for your wireless network, please see the information below, or contact us.
Deploying wireless technology in today's diverse environments requires using hardware and software capable of offsetting and eliminating some of the common negative effects these environments have on wireless signals. Large, cluttered spaces filled with metal shelving and racks, coupled with the varying composition of structural components such as walls, ceilings and roofs, offer an array of factors that lead to poor network performance and, in some instances, failure. This condition is known as Multipath Distortion and can lead to Packet loss, decreased bandwidth, and signal nulling, which can wreak havoc on a network and cause loss of productivity and data.
When signals reflect, refract and diffract off objects, it can delay the packet's arrival and can harm the integrity of the packet as well. The receiving access point will then get multiple versions of the packet and have to shift through them to determine which one it will use. This can confuse the access point, causing errors.
By deploying a Diversity Antenna, you can minimize, if not eliminate, some of these negative effects. Diversity utilizes two antennas instead of one to essentially “pick” the best signal. Due to the antennas being in separate physical locations they are able to sample two different zones in the transmission range. This increases the likelihood the access point will field a signal that’s usable. It will "see" the same signal from two different points of view, compare them, and then pick.
In addition, the 802.11 wireless standard requires that the access point receiving the data send an acknowledgement packet confirming receipt. If the data is corrupt, null or takes too long, no acknowledgement packet is sent and the transmitting access point will re-send. The more bad data, the more re-sent packets and the longer the packets in queue will have to wait to be sent from the transmitting access point.
- Diversity is best used in manufacturing facilities, mills, warehouses, etc.
- Use diversity to cover only one cell at a time.
- Conduct a site survey to identify the final mounting position based on best reception and absence of null points.
- When using diversity antennas that are not in the same housing, the distance that separates them should be a multiple of the frequency (i.e. 2.4Ghz has a wavelength of 4.92", so they should be roughly 5", 10", etc. apart), but should not be more than four multiples apart.