How to read Spectrum Analyzer?

Been following this site for awhile now, trying to learn as much as possible. In regards to the sprectrum analyzer with the 900mhz, how do we read them. I have looked through the on-line knowledger center on this site and some of the past posts. Is there somewhere that explains all about the analyzer. For instance, a how to guide. I downloaded the userguide dated march 05 and have learned a great deal, but I am looking for something more in depth that I can study and prehaps grasp the concept, more then I have now. Any help? Please! Thanks :wink:

When its enabled you will see green bars going up and down. The green bar is the current signal strength for that freq. You will also notice that there is a little yellow line as well. That is how strong the device has seen that signal for that freq.


Moto recommends that all AP’s and backhauls be sepereated by atleast 20 mhz if not more. So for example 2.4 ap’s set to 2415.0 2435.0 2457.5

Those would be your center channel that the canopy equipment uses. From what I understand from support. Adding roughly 6 mhz above and below for each freq.

When useing the spectrum you want to make sure that those freq that you choose are as low and clean as posible meaning the green lines showing
-80 or better depending on your specs to avoid any interferance on that channel.

Keep in mind that if you have other deviced located on the same tower. You will see those in the spectrum. If you Disable those the green lines whould decrease if there is nothing else on that freq.

That pretty much it.

Someone else might be able to explain this better.

So you want to chose the freq. with the LOWEST dbm reading? Meaning 65dbm is better than 80 dbm. I realize the lower the reading, the better or stronger the signal.

wirelessSolutions wrote:
So you want to chose the freq. with the LOWEST dbm reading? Meaning 65dbm is better than 80 dbm. I realize the lower the reading, the better or stronger the signal.


Nope it's the other way round for interference. 80 is better than 65. We are dealing with negative numbers here, and -80 is lower than -65 :D

Panzer

the 900mhz needs aleast 4 mhz spacing motorola recommends 9mhz.

everything else aleast 20mhz motorola recommends 25 mhz.

Thanks sir for this info, it was a nice peice 

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Joewi - Keep in mind that these are posts from 2005 (12 years ago), and refer to the FSK or PMP 100 product.  

The information regarding how to interpret spectrum analysis is still valid, meaning the measurements are negative dBm measurements, and lower equals less noise (i.e. -80 dBm is less of a signal than -65 dBm).

However, the information about guard bands differs with the PMP 450 and ePMP platforms of products (our current product lines).

Thanks for reading!

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Thank sir for that info