Autonomous Warehouse APs and Antennas

[antonios.skoulariotis]

Dear forum members, I am working on a design that involves many warehouses, as well as storage yards/outside coverage.

The current deployment is the cisco 1231 or 1220, with memory limitation.

The environment is autonomous, and it has to remain like that.

The majority of the APs are utilizing external antennas, some with smaller gain since they are inside the warehouse and dsome much higher antennas since they provide coverage to a sizeable yard.

In an effort to upgrade the system, I would like to find an AP that will serve me well in regards to coverage.

I am thinking the autonomous 1242s AG.  Can please someone suggest an AP as well as some external Antennas/Omni for inside the facility as well as some higher gain antennas (Omni or Directional) for the outside space.

I would appreciate your help on this matter.

AS

[Scott Fella]

Do you have good coverage now? The reason I ask is because you don't want to use a high gain antenna to provide more coverage. That will not work! If you plan on just doing a one for one swap because your existing coverage is fine, then maybe look at the 1260 AP's. These can be purchases as autonomous (make sure you pick the correct part number) and requires the use of external antennas. Might be better if you get one I these antennas.

http://www.sparcotech.com/cgi-bin/commerce.cgi?preadd=action&key=SP-MIMO-OD6

This makes mounting easy since all six leads connect to the antenna and you do not have to worry about antenna spacing.

I would still perform a site survey using the 1260 and these antennas just to ensure you still have coverage. I would think that you would need to add more AP's since the requirements back then isn't the same as what is required for data, voice or location.

Sent from my iPhone

[antonios.skoulariotis]

Scott thank you for the answer, I am aware of the capabilities of the 1260 it is indeed a great AP.  I am not designing an 802.11n system.  The environment requires very little data load, it is for handheld devices only, hence I suggested the 1242 AP.  Do you have any objections of the 1242 AP?

Also I am planning on using 4 antennas, the external ones, omni with some high gain depending if I will install the AP inside the warehouse of outside the warehouse.

I have captured airmagnet RF signal measures, and in some areas I need help especially outside, Hence I would like to use a high gain antenna since the environment is huge and assign the right frequency so I minimize interference with the existing AP.

Thank you for your suggestion.

[Scott Fella · Accepted solution]

Well I was just suggesting the 1260, because the 1242 is EOS/EOL. As for the antennas, you can't go with a high gain to give you more coverage. The issue what you will have is one way conversation. You have to look at the tx power of your wireless device and then compare that with the total tx power of your AP which will include you antenna gain. Your client might be able to hear the AP, but your client traffic will never reach the AP. Every 3dbi is double the power.

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[antonios.skoulariotis]

Scott thank you again for this information that I was nto aware off.  I had no idea that the 1242 is EOL.  So 1260 is the answer.

Now in regards to antenna.  I know you have send me a link before.  But what I am wondering me is why do you suggest me not to install additional APs.

let me give you this example.  I have a yard, which is about 500 long and 400 feet wide if not more.  The yard is loaded with iron and wood, in other words the worst enemies of RF.

As of now there is one 1231 AP with an omni antenna, blasting signal out, but cause of the topology of the yard the signal does not reach to the left side as well, the signals are spotty and when I get a singal it is in the -80 to -90 dBm range, which we know it is not great.

I was thinking of installing a high gain antenna, assign channel 1 to the NEW AP since the Old AP is running our of channel 11, and have an external Antenna to provide additional coverage to that section of the yard.

Do you disagree with me?  would you design it another way?  I know the topology of the yard, is weird and lots of space, but I believe that there has to be something that i can do to increase the spotty coverage so I can avoid dropped packets from the handheld devices on the field.

Any of the cisco antennas that you would reccomend?  Much appreciate your help.

[Scott Fella]

No. I'm suggestions that you might need additional AP's to get you the coverage you need. Your issue will be where you can mount these additional AP's. You already know your going to have issues due to the materials being stored in the yard. Now with these AP's, you have to be able to run power or Ethernet to them.

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[Leo Laohoo · Accepted solution]

I can't answer for Scott's decision to recommend the 1260 but I too would recommend the 1260.  You may not be designing 802.11n but WLAN is like "build and they will come".   Designing an 802.11n network now is "future proofing".

[antonios.skoulariotis]

True statement, I did not think of that, since the handheld can support 802.11a/b/g.  It woul dnot hurt if I provide the 802.11n capability and if they do not need it they will not use it.  Thank you Leolaohoo.

[Leo Laohoo]

It woul dnot hurt if I provide the 802.11n capability and if they do not need it they will not use it.

I wasn't thinking about handheld bar code scanners, per se.  I was more thinking about laptops/netbooks, tablets and smartphones.

I really can't imagine handheld bar code scanners requiring 802.11n as of the moment because the data that is being sent/receive isn't very large or bulky.

I haven't even mentioned wireless VoIP yet. 

[Scott Fella]

Take a look at this discussion also regarding antenna gain.

https://supportforums.cisco.com/thread/2116129

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