Wireless Access

Hello.

I've got a setup with several AP-175Ps with D607 antennas and controller which need to cover area. There are places where there is no signal or signal strength is very low. Currently the gain for antenna is set to 7 dBi and transmit EIRP is 25 dBm. Are those the maximux values? Are there any other values that might increase signal strength? How can I check current transmit EIRP on each access point?

You can lower the antenna gain in the configuration to get higher EIRP. The TX-power will be adjusted by the IAP based on the country's regulatory domain Max EIRP and the antenna gain you fill in.

What value do you recommend for antenna gain?

The D609 is a 60 degree sector antenna.  Please take a look at your coverage area and make sure that antenna is appropriate for that application.  Clients on the left and right of the antenna not getting coverage is indication that you need an omnidirectional antenna instead.  This antenna is used frequently for point-to-point coverage as opposed to client coverage due to its focused coverage.

 

What do you have to cover?

 

It's a warehouse with pallet racks. Antennas are attached to walls 20-40 meters above the ground pointing towards bays between racks.

Can you recommend any settings (gain and EIRP) for that setup?

Before I answer, how many AP175s do you have deployed already with those antennas?

Does the warehouse have freezing/very hot temperatures, or is it controlled?

 

There are about 15 access points covering the warehouse. Temperature is normal mostly depending on outside temperature and season. There are no freezing or hot areas.

How far apart are the antennas and how long are the aisles?  How tall are the stacks on the sides of the aisles?  What is the product being stacked...(paper, metal or liquid)?

I have made a diagram of warehouse and where racks and access points (blue squares) are placed.

The racks are about 20-30 meters tall. Mostly paper and solid materials are stored. No liquid and metal.

Okay.

 

Unfortunately, the appropriate antenna for that is the ap-ant-90  http://www.arubanetworks.com/pdf/products/ap-ant-90_ss.pdf because it has a downtilt pattern designed to be able to give ground coverage at those heights.  The d607 is used for point-to-point links and probably will not give good ground coverage to clients at those heights.  The AP105 and AP135 also have built-in downtilt omnidirectional antennas and would be appropriate for this if the temperature does not swing too high or low.

 

With your existing antennas, you could put the power up high, but it is probably too focused coming from the D807 to provide ground coverage at those distances between access points.  See if you could obtain two AP-ANT-90s and measure your coverage.  Do you have anything to do a site survey to see your coverage for the D809s?

 

Before you do anything, you should check out Chuck L, our resident expert's presentation here:  http://community.arubanetworks.com/t5/Community-Tribal-Knowledge-Base/Wireless-Design-for-Stores-Warehouses-amp-Manufacturing/ta-p/21618 to see if any of it applies to your installation.

ANT-2x2-D607 is an appropriate choice. the antennas should be mounted with the pigtails coming out of the bottom off the antenna.

 

the backplate of the antenna shoul dbe parallel to the wall assuming wall mount location

 

To maximise tx power set antenna gain to 0 and set max power on the radio. this will give an incorrect EIRP indication in monitoring SW but will ensure that the max EIRP is being used. In this configuration and with the antenna gain of the 607 you will be in compliance with North American regualroty power levels.

 

What client is used or is this a general issue?

 

Cables should not be stretched. if they are they may be broken

 

As this is indoors i assume that LARs have not been used. they should not be in this case

 

Are you having coverage probelms on 2.4 and 5 GHz?

 

if there a cellular basestation nearby (within a 1/2 mile) or a DAS system in the warehouse?

 

Please see attachd heatmap simulation

Is there any other radio system deployed in the building. any radio operating in the DC to  10 GHz range,

Hello Mate78,

 

I had a similar deployment using AP105 in the pass the only different is that the height is hovering around 15 meters and I mount them on the ceiling top.Only issue is the maintenance of the APs but can be overcome as they should have equipment sisscors lift etc to bring engineers up. It is cheaper and have no issue in term of coverage hole as AP105 is using monidirection APs. Goods are liquid chemicals.

Thanks for valuable information.

Unfortuantely I don't have anything to do a site survey right now but I will try to get a couple of different antennas to see if they accommodate to this setup.

Before you change anything, you might want to walk the floor with you whatever handheld you are using in site survey mode to see the coverage at various points. You may have to move the antennas, but by all means see what you have.

Thanks for the presentation.

It is general issue regardless of clients being used. The problem is with both bands. This setup must compliant with european regulatory rules.

I don't know if there is cellular basestation close to the site or other radio systems inside but probably not.

 

Ok

European power levels are 20 dBm (100mW) in 2.4 and 30 dBm (1000 mW).

In open spaces a laptop will connect in 5 GHz to an AP-175 up to 600m away using the 5 dBi omni kit ANT-2x2-5005.

The 607 has a couple dB more gain at its peak and your deployment is directionally oriented.

Your comments indicate that this is a global issue so this is not an issue with a single client device.

These are my assumptions but I will ask to verify

AP-175
No lightning surge protectors
2 x ANT-2x2-D607 on each AP-175 with no other cables. Pigtails only.
The pigtail cables are not stretched in install and not stressed
The cables were not used as handles when the antennas were installed
The antennas are mounted on a wall
The antennas are installed with the cables coming out the bottom
The back plate of the antenna is installed parallel with the wall.
CSD override disabled
Ant gain set to 7 in both bands
Tx power (EIRP) set to 20 dBm in 2.4 and 30 dBm in 5 GHz.

The only mechanism that I am aware of that can create a global failure would be a very high power transmitter operating between 3 and 4 GHz or individual high power devices below 2.8 GHz and above 4.5 GHz.