WiFi frequency and antennas selection for warehouse environment

[Jerry Cao]

We are about to implement WiFi in our warehouse. Need some advice on the frequency and antennas.

We plan to use Cisco 5508 wireless lan controllers and 3502 APs. We are not sure if we should use 2.4GHz or 5GHz and which type of antennas we should use.

Any suggestions and advice are appreciated!

[Scott Fella]

There are many different factors here. Generally I don't see why you wouldn't enable both bands since you are paying for both. Also if you are using the 3502i, then maybe just use the rubber ducks. There are other antennas out there, but not knowing your environment makes it difficult to help here. How high will these AP's be mounted by the way? Also, have you done a site survey or at least tested the coverage of these AP's in your environment.

Thanks,

Scott Fella

Sent from my iPhone

[George Stefanick]

Jerry,

A site survey is very important. Most warehouses I design I like to use patch antennas and point them down aisles (from the ceiling and pointing downward). This lessens the RF interference from excessive omni's installed to the ceiling. But again, a survey is very important.

[Jerry Cao]

Thanks Scott and George,

A site survey is being done. The APs will be mounted about 9 meters high on the ceiling. We will use external antennas for better coverage. We will enable both bands, but we have to buy double amount antennas unless we use dual band antennas which we don't have many options for.

Can omni antennas provide better coverage? Will the LAN controller optimise the interference caused by excessive omnis?

[George Stefanick]

My experience with Omni's in a warehouse environment and perhaps Scott can share his. If you deploy omnis to the roof structure. Your racks typically dont go right to the ceiling. If you get on a lift above the racks you will see all your omni poles sticking down. What this means is that all the APs can see each other and can cause interference with each other.

I tend to use patch / directional antennas to focus my area of coverage which lessens interference.

Just my 2 cents ...

[Scott Fella]

I agree with George... If you plan on using omni's your best bet is to drop the AP as as low as you can. I have seen a conduit running down to a certain height and the a single/double gain box in which the ap mounts to. If you rely on RRM, you better make sure the AP's are not seeing each other like George mentioned.

Thanks,

Scott Fella

Sent from my iPhone