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Does anyone have a source for authoritative information for antenna patterns for this AP? It has integrated antennas.

The AP technical literature doesn't seem to relate the mounting (suggested as either vertical wall or horizontal ceiling) to the patterns. For patterns, there is a 2.4 GHz and 5 GHz azimuth and elevation in the Cisco Reference Guide for Antennas for the 1130ag series AP. It doesn't specify which mounting position the patterns apply to, and because they are asymmetrical, that is going to make a difference in mounting.

The best information I've been able to get after talking to multiple people at Cisco is that the patterns are probably for a vertically mounted AP with the cables at the bottom.

The 1130ag series patterns in one RF planning tool seem to be the opposite in both orientation and gain from this Cisco information.

I don't have an 1131ag in hand to test, and I hoped to finish the design today. Since the client is appearance-conscious, it would help to know how they have to be mounted.

Thank you.
Charles Preston

Are you saying that the literature states that the AP can be mounted vertically or horizontally?

The data sheet says:
"Built-in antennas provide omnidirectional coverage specifically designed for today?¡é?€??s open workspaces. A multipurpose mounting bracket easily secures Cisco Aironet 1130AG Series access points to ceilings and walls. "

From the Hardware Installation Guide

c. Mount the access point at the indicated destination using the specified mounting method. For specific mounting instructions, see these sections:

?¡é?€?¡°Horizontal or vertical surface, such as a ceiling or wall (see the "Mounting the Access Point on a Horizontal or Vertical Surface" section).

?¡é?€?¡°Below a suspended ceiling (see the "Mounting the Access Point Below a Suspended Ceiling" section).

?¡é?€?¡°Above a suspended ceiling (see the "Mounting the Access Point Above a Suspended Ceiling" section).

?¡é?€?¡°On a desktop or shelf (see the "Mounting Access Point on a Desktop or Shelf" section.

The installation instructions further state that the mounting plate can be installed upside down on a vertical surface for upper cable entry.

Since the elevation pattern shown is distinctly asymmetrical in a "down" direction for vertical? mounting, this would mostly help the floor above. Where floor construction is poured concrete over corrugated steel, I'll bet multipath patterns would be interesting. My recollection is that the corrugation pattern is around a wavelength at 2.4 GHz.

As soon as I read the material above, I was skeptical, but figured there might be some interesting antenna design I didn't understand. Then I read about the 3 dBi gain at 2.4 GHz and 4.5 dBi gain at 5 GHz, and was pretty sure that additional pattern information would clear up the mystery, since it wasn't going to be omnidirectional everywhere with that gain. Especially with no mention of smart beamforming antennas. But I couldn't find the information relating pattern to position.

When I did a site survey (using a 1232AG), the predicted RSSI didn't match what I measured, so I started looking closer at the RF planning software, only to find it didn't seem to match the Cisco information. My previous experiences with predicted vs measured also indicate that it is risky to omit site surveys, or at least some on-site measurements.

Thank you.
Charles Preston

I got additional email from Cisco support saying that he had checked, and that the antenna patterns shown in the Cisco Reference Guide for Antennas are for the 1131AG mounted on a wall, vertically, cable side down.

The RF planning software folks changed their patterns (which had additional problems with the way they displayed gain).

This leaves open the question of why Cisco technical documentation has only one set of patterns but advises mounting either horizontally or vertically for an omnidirectional pattern.

It looks like this will need to be settled (in my mind, at least) by measuring RF from an 1131AG.

Thank you.
Charles Preston

Hi everyone,

I wanted to throw in an update to this post since it came up in my google search.

The current Cisco 1130ag Hardware Installation Guide now clearly states that these APs should only be mounted on a horizontal surface (page 2-12). Otherwise, the internal antennas will begin propagating more directionally, explaining Charles' observations!

David