Mesh & user access RSSI
04-07-2013 03:01 AM
I am in an installation project, which have been completed and the customer is saying that the signal is very bad.
I want to tell that our APs have Surge Arresters installed on them (Which should mean that the signal should be lower compared with AP without Surge Arrestor - insurtion loss will increase).
Now I am looking at the mesh (point-to-point link)
-one of the the links the link quality value is 36 , does this mean there is something wrong ? is this good should it be 40 ? or should be 25 ? or it is just perfect ?
- The second link is 21 is it acceptable or there is a big problem and it is hardly working and the installation is wrong ?! what the value of this should be ?
- The customer saying that the second link should not form and this point should connect with other portal, does the AP point choosed this Portal due to link quality which is better than link quality with other portal ?
- Some APs providing Users coverage, is there a standard coverage test, for the APs ? when I come under the AP the signal strength using inSSIDer is around -55, is that fine ? distributers saying you are having problem with the antenna it is not tight, our tech saying it is tight and if you start moving the connection, the tape will move not the connecter. In addition, the signal can fluctuate too much. and if I am under a car cover with a distance of 60 m the signal can reach 70dbm using InSSIDer, some people telling me that your Dell Latitiude e6400 has a problem in its Wireless Card!!!
- Some APs are installed on a very thick building which I think if I am next the AP but on the side wall the signal drops to -70 to -73 (sometimes can be above) fluctuate. Also note that other AP are installed just behind the trees.
- The Antenna (White part) can move if we surround it when there is a polyphasor, is not it ?
I really do not know how can I tell that the signal is good (or as standard as almost evey Area has its Characteristic.
I am totaly confused with what is ture and where is the wrong part and how things should work and be considered fine/perfect!
Re: Mesh & user access RSSI
04-07-2013 06:45 PM
There's a lot of unknowns here, so I will run down as best I can...
* If by surge arrestors you mean lightning arrestors on the antennas, their insertion loss should be between 0.25-0.5dB at most. For a PtP link that shouldn't retard the signal very much.
* What kind of APs are you working with, MSRs or AP-175s?
* When you talk about first and second link, are you talking about two links between the same PtP? If so, what antennas are on each end? Details of your toology would be needed to know what is and isn't normal/expected and what is out of range.
* When the antenna is attached and torqued properly, and weatherized with mastic and tape, NOTHING should move, not the tape or the antenna connectors. If they are moving or twisting, there's a chance the connector is loose and should be re-connected an re-weatherized.
* Not sure what you are trying to say about client coverage. There's no standard measure or test exept what you standardize on (measure with the same tool using the same client across the site to compare, set baselines between your client and others used on site, etc). Overhead car covers or metal awnings will certainly drop the RF signal (attenuate between 8-15dB depending on LoS from the client to the AP). Same goes for buildings and wall. If the wall is concrete and steel rebar reinforced, you will see large attenuation of RF.
* Not sure what you mean between the polyphasor and white antenna part? Will need more explanation
If you can give us more details on your deployment, AP models and antennas, what links and the topology of the mesh, we can better detail what kinds of SNR you should expect to see. NOTHING should ever be loose, tape or antenna. If something is moving it should be considered suspect and addressed.
Distinguished Technologist, TME