Hi everyone,

I think all of us here have problem with "INTERFERENCE" on our network. Mikrotik gave us so many parameter, like noise floor thereshold,calibration interval etc, so what is the best setting for an AP on a highly interfered environment? Maybe what kind of antenna and mini pci should we use. Would you please all share your experience and knowledge for all of us?

Thank you all

I always enable periodic calbration. For one hotspot I enabled DFS-non RADAR detect which worked great, not so good in a fixed wireless environment if your clients do not automatcally change channel too. Although I have found that using DFS took the guess work out of choosing the best channel for an AP which I then fixed onto that channel. You could install a bandpass filter - choose the quietest channel, once installed you can only use the frequency the bandpass filter is designed for.

I think that everyone who has a problem with WIFI says : " ... Interferences ..." and that´s no real reason everytime....

A good configuration in your APs or a bad one is the difference in a lot of cases....

For example, I had a lot of clients using standars APs (Senao, Micronet, Dlink, Lucent, etc...) with a lot of "INTERFERENCE" problems .... I´d replaced them with MKT + Senao NL2511+ (same frecuency, same TX power, same modulation....) and the problems disappears.... so ... the "Interference" dissapears ??? ... No

In MKTs APs I every use :

NAT
Bandwidth control (Simple queue for standar traffic, per client)
Bandwidth control (Queue tree + mangle, for P2P)
DROP WAREZ P2P Protocol
Default Forward ... NO
Default Authenticate ... NO
A lot of rules in the firewall to stop non-desired packets....
etc...

You cannot use this kind of configurations in standar APs... that´s the great difference, I suppose....

Regards
Sebastian

Configuration for these AP's is very minimal..

What chipi suggested may work for him, but the settings he offers wouldn't do anything to combat interference, they'd just increase the CPU load on your AP.

In my opinion you don't want your AP's doing anything CPU intensive. Save that for a higher end router to handle your bandwidth queues, routing decisions, firewalling, PPPoE server, etc. That way you have more CPU available on your AP to deliver higher throughput.

Using mikrotik's as CPE's has a definite advantage over competing cheaper CPE's. You can use your desired RF card + antenna to design it to fit your application. When you swapped the CPE's for mikrotik's did you see an increase in your SNR and CCQ's? I'd assume you did.

I think Harvski provided the best solution for environments with interference present. Bandpass filters, and such will definitely help clean up the RF side of things. There's not much in the software that will combat interference, save for DFS and changing frequencies.

The fact is if you're using unlicensed spectrum you will see interference. You want to make sure you clients have good signal to noise ratios to provide a "buffer" between the clients signal, and the noise floor. Use high quality antennas especially on the AP end. Stay away from 2.4GHz for fixed wireless applications. It's becoming way too crowded, especially here in the US.

my 2 cents...

DFS does automatic frequency selection correct? How does this work in an enviroment running multiple MT AP's???

From the manual

dfs-mode (none | radar-detect | no-radar-detect; default: none) - used for APs to dynamically select frequency at which this AP will operate
none - do not use DFS
no-radar-detect - AP scans channel list from "scan-list" and chooses the frequency which is with the lowest amount of other networks detected
radar-detect - AP scans channel list from "scan-list" and chooses the frequency which is with the lowest amount of other networks detected, if no radar is detected in this channel for 60 seconds, the AP starts to operate at this channel, if radar is detected, the AP continues searching for the next available channel which is with the lowest amount of other networks detected

This only happens on start up of the interface and reading this information it might be better to always use the RADAR detect too so that the quietest channel is used radio wise as well as number of wireless network... Maybe MikroTik could fill in the gaps as to what DFS is looking for.

I don't use DFS on my Fixed Wireless network as I'm also using 2.4GHz for backhaul as well as the AP. I can imagine chaos might occur if I did use it.