I have read numerous discussions on problems regarding self interference 
between two mPCI cards inserted in the same SBC, on same Freqs.  Some 
reporting need for 40Mhz of center channel seperation.

These are the factors...
U.FL vs MMCX connectors
One vs two Antenna Ports on a single mpci card  (for example will second 
unused antenna port on card without pigtail hear noise. Does the second port 
need to be terminated?)
Proximity of mPCI slots to each other. (ADI/Lucaya side by side versus MT 
433 Stacked)
High power embedded amped  vs low power cards.
Software thresholds vs not (min and max receive threshold and adapative 
noise immunity)
Bleed over at card versus bleed over at antenna. (polarity won't help at 
card's port)
Interference from Antenna port RF vs internal electronics generated RF noise 
(used to see this in PCs if HDD were to close to MB)
One manufacturer's card vs another's.
Receiver overload vs interference

Unsubstantiated guestimates about this topic won;t really help because there 
are a LOT of variables contributing to the problem.

MT433 or equivellent will most like work excellent if each card has a 
different freq such as 2.4, 5.8, and 900. Unless the problem is Receiver 
Overload. Where in that case maybe 2 CM9s could work better even if both on 
adjacent channel 5.3? If interference is based on Antenna placement, well 
thats easilly controllable by a field tech at time of installation. But what 
I'm concerned about is knowing that the radio system itself is made to be 
non-ninterfering internally. From a remote management perspective, its going 
to be painful tracking which radio systems have to be how far apart in 
channels to not interfere troubleshooting on-the-fly, without some baseline 
stats defined a head of time.

So this brings me to three questions of higher relevence.....

1) What do we need to do to guarantee that two cards can co-exist and be 
used on adjacenet channels without interference at the radio card hardware 
level  (not including antenna placement factors that could allow intference)

2) Has anyone actually used a Spectrum Analyzer or Noise meter to actually 
measure the RF bleed between to mounted cards? With accurate results of what 
the interference levels are?

3) Would WISP members be interested in contributing to a small fund to pay 
someone to actually accurately measure the results for us?

I'd like to specifically know for the 433 board. If using the higher quality 
MMCX w/ single antenna port cards (MT brand card), will 10Mhz of channel 
seperation be enough, to get two 5.3Ghz channels operating correctly?

Tom DeReggi
RapidDSL & Wireless, Inc
IntAirNet- Fixed Wireless Broadband


----- Original Message ----- 
From: "Eje Gustafsson" <e...@wisp-router.com>
To: "'WISPA General List'" <wireless@wispa.org>
Sent: Monday, April 20, 2009 4:39 PM
Subject: Re: [WISPA] is this router overloaded?


> And 5.2 is not allowed for outdoor usage. So Franks unit is an indoor unit 
> I
> would suspect he is suffering from multipath reflections.
>
> Besides on the radar stuff.. The way DFS is designed in MT it will never 
> be
> able to get certified. First of it must continuously look for and detect
> radar not just when it first enable the interface. Secondly it at least 
> did
> a horrible job in actually detecting radar signatures.
>
> Besides 5.2 is not part of the band you can use even with a certified 
> radar
> detecting device.
>
> / Eje
>
> -----Original Message-----
> From: wireless-boun...@wispa.org [mailto:wireless-boun...@wispa.org] On
> Behalf Of Dennis Burgess - LTI
> Sent: Monday, April 20, 2009 3:32 PM
> To: WISPA General List
> Subject: Re: [WISPA] is this router overloaded?
>
> Part of the 5.2 band.  All of the radar patters are in MT, just not
> certified.
>
> * -----------------------------------------------------------
> Dennis Burgess, CCNA, A+, Mikrotik Certified Trainer
> WISPA Board Member - wispa.org <http://www.wispa.org/>
> Link Technologies, Inc -- Mikrotik & WISP Support Services
> WISPA Vendor Member*
> *Office*: 314-735-0270 *Website*: http://www.linktechs.net
> <http://www.linktechs.net/>
> */LIVE On-Line Mikrotik Training/*
> <http://www.linktechs.net/onlinetraining.asp>
>
> The information transmitted (including attachments) is covered by the
> Electronic Communications Privacy Act, 18 U.S.C. 2510-2521, is intended 
> only
> for the person(s) or entity/entities to which
> it is addressed and may contain confidential and/or privileged material. 
> Any
> review, retransmission, dissemination or other use of, or taking of any
> action in reliance upon, this information by persons or entities other 
> than
> the intended recipient(s) is prohibited, If you
> received this in error, please contact the sender and delete the material
> from any computer.
>
>
>
>
>
> Gino Villarini wrote:
>> 5180.....hmmm!!!
>>
>> Not to bust anyones head but you are using an uncertified device on an
>> illegal channel
>>
>> Sent from my Motorola Startac...
>>
>>
>> On Apr 20, 2009, at 3:20 PM, "Josh Luthman"
>> <j...@imaginenetworksllc.com> wrote:
>>
>>
>>> Gino - Top right corner.
>>>
>>> Did the CPU just jump or has it casually been like that?
>>>
>>> I've never had 5 radios in any board, I don't know if that would
>>> cause a lot
>>> of usage or not.  Most any MT box I've seen is <5% CPU.  A lot of
>>> NAT as was
>>> mentioned would be the first place I'd look.
>>>
>>> Josh Luthman
>>> Office: 937-552-2340
>>> Direct: 937-552-2343
>>> 1100 Wayne St
>>> Suite 1337
>>> Troy, OH 45373
>>>
>>> Those who don't understand UNIX are condemned to reinvent it, poorly.
>>> --- Henry Spencer
>>>
>>>
>>> On Mon, Apr 20, 2009 at 3:14 PM, Kevin Neal <ke...@safelink.net>
>>> wrote:
>>>
>>>
>>>> Is this doing any NAT?  Is connection tracking enabled?  Do you
>>>> have all
>>>> unneeded packages disabled?  We have a few RB600's out there and
>>>> they do
>>>> fine for the most part, we don't do any wireless on the 600's and
>>>> all of
>>>> them have the 564 daughterboard in them.
>>>>
>>>> -Kevin Neal
>>>>
>>>>
>>>>
>>>> -----Original Message-----
>>>> From: wireless-boun...@wispa.org [mailto:wireless-
>>>> boun...@wispa.org] On
>>>> Behalf Of Kurt Fankhauser
>>>> Sent: Monday, April 20, 2009 12:50 PM
>>>> To: 'WISPA General List'
>>>> Subject: [WISPA] is this router overloaded?
>>>>
>>>> I have a RB600 here that I've taken a screenshot of. No interfaces
>>>> are
>>>> bridged, everything is routed and I'm noticing some lag in the
>>>> traffic that
>>>> passes though this device during peak use. I suspect that the 41
>>>> RIP routes
>>>> might have something to do with it as actual throughput isn't that
>>>> much
>>>> sometimes topping out around 8Mbps. Just want to hear from others
>>>> and if
>>>> there is any suggestions on how I might speed this up let me know.
>>>> CPU
>>>> usage
>>>> on it is around 40-50%.
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> Kurt Fankhauser
>>>> WAVELINC
>>>> P.O. Box 126
>>>> Bucyrus, OH 44820
>>>> 419-562-6405
>>>> www.wavelinc.com
>>>>
>
>
>
>
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