Has anyone had success with these kinds of antennas? Tell your success and fail stories here please.

Has anyone had success with these kinds of antennas? Tell your success and fail stories here please.

Yes! Very interesting theme. We want to do some tests soon using Mars Dualpol R5H.

Esp. what do you do to get maximum separation between the 2 radios. I've heard
that some guys put 2 complete boards into the compartment of a dualpol antenna
just to separate the Wireless cards/pigtails.

Does it improve speed to use one radio per direction?

What channel separation is neccessary?

Stefan

I did not tried cross-pol antennas (yet) but here is some numbers:

- Isolation between ports aprox 25 ... 30dB (if a good feeder is used): this means that a +20dBm signal from one port will show up at the other port as -10dBm better case. Is there any Mini-PCI card that can handle that, even operating at the band edges? Probabily the receiver will desense due to front end overload.

- Single braid cables must be avoided between cards and antenna connectors: choose dual shield or semi-rigid ones.

- Better isolation with two completely sealed (RF point of view) boards + mini-pci cards. RF is like water . Leaks thru power supply wiring or ETH cables from one radio may show up at the other.

Now: if someone make both cards that shares the same antenna run at the same TX-RX cycle (e.g both TX and both RX at the same time slot) the answer is yes - you can share the same xpol antenna at adjacent frequencies or even at the same frequency if receivers can handle a -22 ... -25dBc interfering signal (e.g ideal attenuation introduced by oposite polarizations affected by some propagation effects).

If cards can handle the -10dBm signal from a different channel at RX input and if modulation scheme is not affected by an interfering signal which is -35dBc (intermod products from on-air TX at the adjacent channels) may be system run without time-slot sinc using different channels.

I don't know how good those mini-pci cards are under co-channel interference but I saw PTP full-duplex systems using the same channel with 32 or 64 QAM modulation with zero BER if the oposite polarization signal was at least -25dBc. I don't know this numbers for OFDM. And there is the Sat TV business, sharing analog or digital video at the same channel but oposite polarizations (linear or circular). Feeder isolation is the same. The path propagation phenomena are not.

Software sometimes (firmware) can handle that, a routine called XPIC (cross-pol interference cancelling).

Regards;

No problem at all.

With bonding we have a link with 24km running with the mars antennas. The only thing you have to regard is avoiding overlap of the scan list. Stations searching for AP will kill the already established link.

I was not able to setup a perfomant NS-Dual-System (RB433). The bandwidth was very low (4 Mbit/s). The duplex distance was maximum possible (5180 vs 5850).

Now I am waiting for 802.11n to build a system with it.

No problem at all.

With bonding we have a link with 24km running with the mars antennas. The only thing you have to regard is avoiding overlap of the scan list. Stations searching for AP will kill the already established link.

I was not able to setup a perfomant NS-Dual-System (RB433). The bandwidth was very low (4 Mbit/s). The duplex distance was maximum possible (5180 vs 5850).

Now I am waiting for 802.11n to build a system with it.

What is your running configuration? Mars with compartment or external antenna? One Board with 2 cards or 2 Boards
with one card each? What card? 20/40 Mhz channels? What is the real bandwidth?

Stefan

We have a 93km link with Dual pole Andrew Dish's (900mm)

Both pol's have a Nstreme link with AP bridge and station_wds , the bridge at each end has rapid spanning tree to resolve packet storm issues.
At certain times of the year it gets bad signal fade so hence the failover between the polaritys, space diversity would fix this but we cant be bothered at the moment.
Signals are -59 and -69 - Difference being mainly one is running 5300Mhz and the other more in peak of dish at 5800mhz
Xr5 cards too.
Been like for for well over 1 year.

So to answer the initial question, it works well and have had no problems.

we have many other shorter links configure the same working fine, the x-pol seperation is good on the Andrew dish so you can run the frequencies quite close without any forseeable negative effect.
Im about to try some dual nstream soon and looking forward to see what that performs like.

Cheers

Justin.

@ste

Single RB433AH, Bandwidth is with turbo about 60 MBit/s HDX (regarding eirp). But this is only an emergency solution (while I wait for 802.11N) cause we are loosing a lot of spectrum.

ähh, I forgot:

Antenna is mars with compartment.

Hi Justin,

OT but where do you buy your Andrew's dishes from in NZ ?


Regards,


Andrew

Hi All

Try this antennas! they have 53 Db isolation betveen H & V pol!!http://en.jirous.com/antenna-5ghz/jrc-29-duplex
We will be starting to sell this unit soon.

Hi Justin,
OT but where do you buy your Andrew's dishes from in NZ ?
Regards,
Andrew

You cant get the px#f series of 5ghz dish's any more sadly as Andrew stopped making them, they have been the best units we have ever had, quite pricy but best quality all round by a long shot.
Otherwise for other andrews stuff Ideal electrical can get things for you (if you know what your after)
Cheers

Hi,

Have you had any experience using two radios (full duplex) over a single antenna with narrow band filtering like the Tranzeo TR-CS1?

Regards,
Daniel G.

Poynting's dual-pol 5Ghz enclosure/antenna has worked great for us. An RB600 fits inside.

Hi Normunds.

Successful with 2 oiwtech 32dbi 5GHz dual polarization antenna, using RB600, Mikrotik R52H and nstreme dual.

1 frequency on 5.8
other on 5.3.


72km spot and 20megabits one way.
10megabits +- both ways.

if you need more description and screenshots I can make.

best regards from brazil
vince de luca

what about no dual-polarization but those antennas which have two on one panel? I think there are such also available, with two connectors.

mramos, has exactly the right concept it is all about the isolation of one signal from the other, it doesn't really matter the configuration of the actual antennas only the raw numbers.

I used to use signal-pol 29 dBi dishes and would put 2 of them up wired to 2 seperate radio enclosures. Antenna seperation was about 10ft, boxes were aluminium but close together (1.5 ft apart). Using this method and any form of fdx (routing, bonding, etc.) was a mess. I typically got better performance when runnning one antenna at a time.

However after the initial mess, we decided to wire the antennas to one enclosure and run dual-ns for comparison purposes. Now remember Nstreme dual is a RouterOS only feature and the beauty of it is one radio is locked doing only Rx, and the other only Tx. This was a huge advantage as the 802.11 ack commands were always sent on the same radio (this is contrary to the seperate enclosure where even though each radio must be doing both Rx and Tx). Performance jumped and we got a much more reliable fdx link.

After that test we evaluated 29 dBi dual-pol dishes, repeated both scenarios, and came out with similar results. Why? Well if you do a signal scan in both setups you would find there is not alot of additional isolation with the antennas seperated the vertical signal is still being picked up by the horizontal antenna and vice versa.

Rule of thumb... max isolation between signals = better performance, it doesn't matter how its achieved.

To answer normis, the panel style dual-pol antennas we use, are built with two antennas on one PCB and have seperate connectors for each, the performance is the same as the dual-pol dishes.

The only approach I have wanted to try but haven't due to the loss in flexibility was to use a signal filter (bandpass filter). Most products that are built for FDX use this to achieve signal isolations >45 dB on top of what the antenna is already doing, and as mentioned earlier some custom FDX solutions would use software to futhor isolate the signals before the actually radio would 'hear' it.

Cheers

MyThougts et al.

I had severe problems at a X band instalation (8GHz), where the customer did not want to spent on bandpass filters at the TX side because "TX frequency was 650MHz away". Make him understand that the transceiver generates background noise, the SSPA generates out of band bg noise was a hard task. At the end, the receiver was completely blocked by wideband bg noise from PA + xceiver. A 135dB isolation was necessary. So ... we added the TX filters and solved the problem.

On those 802.11A/B/G radios I think the safest way to put them at the same antenna - and - keep all the avialable frequencies or reach predictable and repeateable results is: both V&H on one side TX and RX at the same time slot. May be using a single clock source for both, I don't know. Have those cards a "clock pin" or an external TX/RX pin for TDM sinc?

Microwave filters are basically mechanical stuff and to be good need to be machined at a CNC. Tuned ones have losses between 1.5 and 3dB if you use the adjacent channels as stopband transition. Waveguides ones when silver plated internally can exibit loss as low as 0,3dB and can be built for a single channel with this loss and good group delay figures (modem taps can handle that). But we always needs two filters, one for TX and another for RX (4 total at one side). The RX filter kills the TX channel. The TX filter kills the out of band noise at the RX frequencies.

And the leaks ... on bandscan I can detect full scale signals from a Ubiquiti SR9 (its 2.4G stages) using an SR2 3 meter away. Note that the SR9 is not connected to any antenna but to a dummy load good up to 12GHz. And the SR2 uses a bi-quad antenna with a 0.45m² reflector. My idea was a 900MHz NLOS link and a 2.4AP at the same X86 card. But with those leaks ...

All PTP microwave radios have sealed compartments for TX & RX. Diplexer isolations ranging from 135 to 160dB depending on TX power.

Regards

Currently we have 5 dual polarity antennas available:
1. Jirous - parabolic dish - 29dBi/29dBi gain @ 5400-5900
2. Jirous - parabolic dish - 23dBi/23dBi gain @ 5400-5900
3. Mars MA-WA56-DP25N - flat panel antenna - 25/24dBi gain @ 4950-5850
4. Mars MA-WA56-DP25 - same as above but frequency range is only 5400-5850
5. MTI 485025/NVH - flat panel antenna - 23dBi gain @ 5000-5950


My personal favorite is MTI, because it has about 50dB of separation depending on frequency, which allows you to make nstreme dual link with high power cards (maximum power without rx errors is 24dBm) and has very wide bandwidth from 5000 to 5950 - you can find many clean chanells
We have about 100 links with these antennas, without any problems, from 30m to 14km, performance is about 80Mbits full duplex with strong&clean signal @ 5GHz turbo

Note on Mars antennas - they have two models, unfortunately, new mode (with N) has more bandwitdh, but speparation is not enough (only 25dB) witch makes this antenna completely unusable with atheros cards.
The "old" MARS without "N" has about 38-42dB of spearation, depending onf frequency, this is enough in most cases but tx power should be as low as possible 14-17dBm works good.

About Jirous, personaly i don't like dishes, but 29dBi model is very good antenna for nstreme dual, especialy over long links (over 15km). We have case with 18km link, @ 82/78Mbits signals -57dBm


About frequencies, with spearation over 40dB (especialy with MTI & Jirous) , you can easily use chanells with only 40-50MHz separation, for example for turbo 40MHz chanells: 5500MHz (5480-5520) --- 50MHz space --- 5590MHz (5570-5610)

My personal favorite is MTI, because it has about 50dB of separation depending on frequency, which allows you to make nstreme dual link with high power cards (maximum power without rx errors is 24dBm) and has very wide bandwidth from 5000 to 5950 - you can find many clean chanells
We have about 100 links with these antennas, without any problems, from 30m to 14km, performance is about 80Mbits full duplex with strong&clean signal @ 5GHz turbo

Are you running RB433's with N-Streme dual in these MTi's?

Are you running RB433's with N-Streme dual

theoretically it's possible to make one, but i'm using boards with faster cpu 433AH/600A or ALIX

Hi,
I experienced big problems with dual-polarity antennas.
I setup two links (7 KM and 5 KM) with MARS Antennas MA-WA56-DP25SBRF -> http://www.mars-antennas.com/item/g_ant ... 1-156.html

The signal is very good, and both single polarity are working well. I have about 35-40Mbps in turbo mode.
But when I activate both polarizations (H + V) then both links become very unstable: high delay, disconnect -> and the link becomes unusable.

I try many things:
- replacing the wireless card: R52 and SR5
- to use two separate RB serving the separate polarization
- In any case I try any possible frequency combination
- I also try an other Dual-polarity antennas (unfortunately I don’t have here the exact model of these antennas)

My conclusion is that dual polarity antennas are unusable!

What I can’t understand is why when I setup a short laboratory link (with a distance from few meters to 100 meters) the antenna was working well.
When I increase the distance to 3 KM, I get an unstable link.

Can anyone explain me the reason of this behaviour of dual polarity antennas?

Many thanks
Regards
Stefano

Hi,
I experienced big problems with dual-polarity antennas.
I setup two links (7 KM and 5 KM) with MARS Antennas MA-WA56-DP25SBRF -> http://www.mars-antennas.com/item/g_ant ... 1-156.html

Which version of this antenna do you have ?
MARS manufactured TWO versions of this antenna, both are looking smilar, but if you have version with connectors (SMA or N) very close to each other (2cm)- that's probably DP25N

I try many things:
- replacing the wireless card: R52 and SR5

That won't help, almost every atheros has the same rx sensivity, and the same saturation threshold on RX

- to use two separate RB serving the separate polarization

That won't help, problem is within antenna not RouterBoard, but still we have much better thoroughput on RB600/ALIX boards than 433' Ones

- In any case I try any possible frequency combination

That won't help, but currently i'm not shure exactly why, my opinion is that strong interference signal causes RX LNA to saturate themself

- I also try an other Dual-polarity antennas (unfortunately I don’t have here the exact model of these antennas)

If you're interesed in good Dual Polarity antennas (or complete nstreme dual links) write me an email - i can send you 2 pcs for tests - if there's any problem with performance on both polarizations - i'll return your cash

My conclusion is that dual polarity antennas are unusable!

Thats not true.
We have hundreds of them working, some of them are on Nstreme Dual links with througput 70Mbps full duplex

What I can’t understand is why when I setup a short laboratory link (with a distance from few meters to 100 meters) the antenna was working well.
When I increase the distance to 3 KM, I get an unstable link.

Can anyone explain me the reason of this behaviour of dual polarity antennas?

When your wireless interface has good signal (-60 or better) it tries to connect with 54Mbps (or 54*2 with turbo) speed.
When interface has 54Mbps wireless tx rate - the card transmit data with lower power - for example 6-24Mbps is 20dBm (100mW) and 54Mbps is only 12dBm (16mW)
Many many times with dual polarity links i needed to lower actual tx power or set higher tx speed manualy to push link with maximum performance.

Hi marksx,
this are good news for me !

Which version of this antenna do you have ?
MARS manufactured TWO versions of this antenna, both are looking smilar, but if you have version with connectors (SMA or N) very close to each other (2cm)- that's probably DP25N

The Mars I'm using are SMA.

If you're interesed in good Dual Polarity antennas (or complete nstreme dual links) write me an email - i can send you 2 pcs for tests - if there's any problem with performance on both polarizations - i'll return your cash

I will contact you asap

When your wireless interface has good signal (-60 or better) it tries to connect with 54Mbps (or 54*2 with turbo) speed.
When interface has 54Mbps wireless tx rate - the card transmit data with lower power - for example 6-24Mbps is 20dBm (100mW) and 54Mbps is only 12dBm (16mW)
Many many times with dual polarity links i needed to lower actual tx power or set higher tx speed manualy to push link with maximum performance.

Interesting thing, you are saing to fix power (low) and speed (high). I can try

regards
Stefano

The Mars I'm using are SMA.

Yes, but look at the picture:


the N connectors are about 10cm from each other, the DP25N has only 2cm space between connectors

like this one:



DP25N are completely useless with atheros based cards


For fixed tx power try 10dBm use 36Mbps rate with turbo - with signal > -73dBm you should get 60Mbps fdx on nstreme dual

I am using a dual polorised antenna that has pole seperation of -32dB.

I can pass 36Mb through a 28km link but when I turn on the second radio card on the horiz polarity the speed drops to 16Mb. I get the same results when I do the experiment the otherway round (Horz on Vert Off). I am using RB433AH and XR5's. My link is -59db. Vert is 5180Ghz and Horz is 5800Ghz (loads of frequency seperation.) I am not passing any data over the second link, just registering it and then the first polorisartion is affected.

I have seen dual polorised antennas with -53dB from another supplier and maybe this is the way to go ? Or maybe I should use less powerfull cards such as R5H's

I also can get better results when I turn down the XR5's to a power level of 18db using card rates in the TX Power. I do not like doing this as I always get worse results when default power is not used even when I fix the Data speed to 32Mb/32Mb or less.

I am using Nstream but not dual Nstream as this makes the situation much worse.

From my experience minimum 40dB of separation is needed to ensure quality of dual link
Some antennas doesn't have such separation, so they're not suited for this type of work.
If separation is low (eg 39-41dB) you need to lower your TX power on TX interface, because crucial is signal on RX interface it can't be too strong .
I've bad experience with tx power > 24dBm (like 28dBm default XR-5 power) i couldn't push more data than 40Mbits fdx, with power 22-24 it's way more stable

We have a lot of VERY GOOD links with PAC WIRELESS Dual Pol :

29 dbi and 32 dbi

You can use these antennas in 5.1 to 5.8 ghz, so you can make TX in 5.2 and RX with 5.7 for example...

We are using them with :

Mikrotik
Ubiquiti
Motorola OFDM
REDLINE
Etc...

http://www.pacwireless.com/products/HDDA5W.shtml

Regards

Is anyone using dual polarity sectors antenna at their base station? If so, what manufacturer and model used?

Hi Chipi

We have a lot of VERY GOOD links with PAC WIRELESS Dual Pol :

29 dbi and 32 dbi

We too are using the PAC WIRELESS antenna's 29dbi model. I am using the radome too. We have XR5's installed into 433AH's on both ends. These are the antenna's that are giving us trouble.

All works well until I turn on the second polarity and the first link goes crazy. I am using the vert on 5.180Ghz and the horz on 5.700Ghz. Both wireless interfaces are set to single nstream. All other settings are set to factory default in the wireless interfaces.

The link is 29km and perfect clear line of sight.

Can you confirm your config ? Are you using nstream dual ? What throughput are you getting ? Radio Cards being used ?

Have you run the bandwidth tester pushing traffic in both directions ?

Sorry about all the questions but our link is not performing very well at all.

Is anyone using dual polarity sectors antenna at their base station? If so, what manufacturer and model used?

Yes, we are using 16dbi vert/ 16dbi horz dual pol 90 degree sectors. They seem to be performing well although I have not tested them extensively. We have many installations with 4 sectors installed giving 360 degrees coverage in horz and vert.

I am buying them here. http://www.irishwireless.eu/shop/item.aspx?itemid=270
I think that they are made by ITElite.

hello marksx.

we had problems in setting up links using dual-polarization antennas.
tested various channels, different configurations of tx power, always getting the same result:
high signal but bad quality connection when activating the second polarization.
The antenna that is tested Kathrein 824 008.

I'm interested in testing with the antenna that you indicated.

Hi Chipi

We have a lot of VERY GOOD links with PAC WIRELESS Dual Pol :

29 dbi and 32 dbi

We too are using the PAC WIRELESS antenna's 29dbi model. I am using the radome too. We have XR5's installed into 433AH's on both ends. These are the antenna's that are giving us trouble.

All works well until I turn on the second polarity and the first link goes crazy. I am using the vert on 5.180Ghz and the horz on 5.700Ghz. Both wireless interfaces are set to single nstream. All other settings are set to factory default in the wireless interfaces.
The link is 29km and perfect clear line of sight.
Sorry about all the questions but our link is not performing very well at all.

I too have had the same sort of issues with these antennas.
I haven't extensively trialed them on dual pole links but the one short 5km link ive done running dual nstream doesnt behave as it should.

Cheers

Is anyone using dual polarity sectors antenna at their base station? If so, what manufacturer and model used?

Yes, we are using 16dbi vert/ 16dbi horz dual pol 90 degree sectors. They seem to be performing well although I have not tested them extensively. We have many installations with 4 sectors installed giving 360 degrees coverage in horz and vert.

I am buying them here. http://www.irishwireless.eu/shop/item.aspx?itemid=270
I think that they are made by ITElite.

Thanks for the reply. Hoping I can get these here in the US.

I found this antenna the MTI MT-484026/NVH cost roughly $800-up from various suppliers. I planning on doing a test deployment with a couple of these or two Pac Wireless sectors (1 vertical and 1 horizontal) with the new 802.11n technology. The Pac Wireless solutions seems more cost effective at the moment.

I found this antenna the MTI MT-484026/NVH cost roughly $800-up from various suppliers. I planning on doing a test deployment with a couple of these or two Pac Wireless sectors (1 vertical and 1 horizontal) with the new 802.11n technology. The Pac Wireless solutions seems more cost effective at the moment.

This seems expensive. I have 90 degree H/V sectors with 16dbi dual polarized (Not 60-DEGREE 16DB as per MTI MT-484026/NVH) The cases that I am using can hold a 433AH or an RB600A internally too.

Check this link http://www.irishwireless.eu/shop/item.aspx?itemid=270

Quote Bushy.. Edited later by Interpoint (http://wirelessconnect.eu/ is also a very good company)

Price is 175.00 euro !
I have about 10 of these in the field and all are working fine.

For Interpoint:

http://wirelessconnect.eu/ might be worth a look too

For Interpoint:

http://wirelessconnect.eu/ might be worth a look too

You are right Bushy.. I have also bought kit from these guys and they are very good suppliers.

I could not find their dual sectors on their website though. I am sure they could supply though.

Hey guys, Dual Pol Sectors have been on my wishlist for some time, just seen available for the first time by the posts here.

I looked at the link from irishwireless.eu and it was a dead link, I also e-mailed wireless connect for more info


But, what is the Model# of the dual-pol sector that you have 10 of in the field?

Your answer is eagerly awaited,
Josh

Some Dual polarity antenna manufacturers:

http://www.itelite.net/ ( Tested them and work great)

http://www.poynting.co.za/ ( Not tested )

Interesting tread normis.

But not seen any post re. dual band antennas yet.....
I am thinking of using 90 or 120 degree sectors for both 2,4 and 5 (5.4-5.7Ghz) frequencies.
Since polarity will be the same (V) I expect more problems then dual polarity antennas when it comes to noise-over or interference.

But dual (even tri-band) antennas are manufactured (http://www.stelladoradus.com/dual.tri.band.antennas.php) and I would like to know if anybody has any experience or say to share on this forum...

I am going to setup several links with dual pol. antennas like http://landashop.com/catalog/pack-dual- ... p-927.html, on 2 - 8 km links.
Hope to tell a succes story in some weeks time!

I am only not sure if I should use dual n-stream or just bond to links?
Previously my single freq. back haul links with n-stream wasn't performing well for real time traffic (VOIP etc.) under slack conditions. Since people also make calls during slack times this was very frustrating. Switched all my links back to normal.
The maximum throughput on nstream was only slightly higher anyway (bandwith speedtest showed only 1Mb max. increase when nstream was enabled.)
So how would this reflect on dual-n-stream with dual polarity antenna compared to bonded channel interests me. Any input?

Previously my single freq. back haul links with n-stream wasn't performing well for real time traffic (VOIP etc.) under slack conditions. Since people also make calls during slack times this was very frustrating. Switched all my links back to normal.

The new version of nstreme, in the wireless test package, fixed this problem many months ago.

Previously my single freq. back haul links with n-stream wasn't performing well for real time traffic (VOIP etc.) under slack conditions. Since people also make calls during slack times this was very frustrating. Switched all my links back to normal.

The new version of nstreme, in the wireless test package, fixed this problem many months ago.

Give me more info please. I use wireless test package since some months because is has RTS/CTS. I see no difference in the nstream funcionality (winbox options) then on the normal wireless packages.

Actually, if I understand well does nstream perform well under load conditions because it makes better use of frame filling but that means under low load conditions sending of frames are delayed because there is not enough data yet?
How is that solved then?

And sorry, but we are drifting off topic here.....

Previously my single freq. back haul links with n-stream wasn't performing well for real time traffic (VOIP etc.) under slack conditions. Since people also make calls during slack times this was very frustrating. Switched all my links back to normal.

The new version of nstreme, in the wireless test package, fixed this problem many months ago.

Give me more info please. I use wireless test package since some months because is has RTS/CTS. I see no difference in the nstream funcionality (winbox options) then on the normal wireless packages.

The settings are the same, it just works much better when it comes to PtMP and latency.
http://forum.mikrotik.com/viewtopic.php?f=7&t=27302

Any experiences with ARC dual pol panel?
http://www.xagyl.com/store/product.php? ... 309&page=1

ARC gear in general?
It claims 40dBm separation...

We do this all the time.

Most dishes typically exhibit 25-35db of isolation. We also use MTI dual pole panels (MT-485025/NVH) with no issue as well. (Motorola uses this antenna on their integrated PTP products).

Whether R52s, CM9s, SR5s, or XR5s, they all work fine. We have used as little separation as 60mhz between 20mhz channel centers.

Pigtails are adjacent to each other with no noticeable IM. You will typically be able to see your other pole at around -38 if you are radiating 26dbm.

We've used this on 100m shots all the way to 23 miles and most often in the 6 mile area with 23dbi panels.

I've only used ARC single pole panels, but have used two butted against each other with normal results - that being full rate thruput.

Matt

Any experiences with ARC dual pol panel?
http://www.xagyl.com/store/product.php? ... 309&page=1

ARC gear in general?
It claims 40dBm separation...

I get good speeds using that antenna with the R52N.

Most dishes typically exhibit 25-35db of isolation. We also use MTI dual pole panels (MT-485025/NVH) with no issue as well. (Motorola uses this antenna on their integrated PTP products).

Whether R52s, CM9s, SR5s, or XR5s, they all work fine. We have used as little separation as 60mhz between 20mhz channel centers.

We also use the MTi's but even with the R52 we have had to dial down the output power to get these to work but believe this to be inteference within the enclosure. Do you use any shielding within the MTi enclosures to get 2 XR5's working in these?

Any experiences with ARC dual pol panel?
http://www.xagyl.com/store/product.php? ... 309&page=1

ARC gear in general?
It claims 40dBm separation...

I get good speeds using that antenna with the R52N.

Hey RK,
What sort of speeds, distance etc.?

Responses to a few posts....

My experience with the single pole version of the ARC antenna... we have several links at 7 miles and 40mhz wide channels in the -60 range with 100% ccq.

Here is a pic of a typical enclosure with 2 CM9s. We have hundreds in this type of enclosure with 3 CM9s, SR5s, and XR5s, as well as a mix of SR9, XR9, SR2, XR5, SR5, CM9, EM9, R52, R5H, and R52Ns.

We have stopped using R52s (and R5Hs) as we have had terrible performance with them - especially on links longer than 2 miles.

Matt

Here's a shot of ADI AE-1 enclosure, Mikrotik RB600A, UbiQuiti SR71-15, a L-com 28.5 dBi Broadband Parabolic Dish Antenna, and an old Primestar roof mount.

From the Front...

I don't believe i have line-of-sight with this link, this is what i get.

matt & fibrewire, can you both e-mail me pictures of your grounding setups on towers, and inside your enclosures.

amirm@tierpath.com

only thing grounded is a wire that goes from the mounting plate on the back of the ADI AE-1 enclosure to cold water ground at both locations. Maybe I should get actual grounding equipment? Lightning arrestors?

Any Suggestions?

Polyphaser, transtector, or citel.

I was actually hoping you had already done it and had pics to share.

OT, but, I wonder is 2T2R+NStreme Dual Possible with 802.11n, maybe 600Mbps?

If you look at the enclosure I posted, you'll see the 2 LSXL-MEs and the Citel. The MJ8 is grounded to a lug which is passed through to the enclosure. The LSXLs pass thru and the enclosure paint is stripped on the inside, and penetrox is applied on both sides of the o-ring, thus ensuring decent ampacity. Depending on the site, we may also pass a 2AWG conductor from another lug inside to a down conductor, though this is not common. All connection points including the lugs inside are penetroxed.

Ever tower is a bit different. On angle braced tower we normally use a Harger 213T flat plate to a bar if we have more than 2 connections, then all units are grounded via independent connections. Bonding to down conductors is always preferable if available. Code in the area, along with improved (and recent) tower regs, state that 2AWG is the minimum required conductor. Ribbon is also allowed as long as the correct minimums are observed.

In the past 5 years, we have had 2 lightning attributed failures on the 1000+ links we have installed and maintain. Those were an Orthogon Gemini and a Proxim 5054. The Gemini antenna and enclosure were melted. The 5054 was toasted via ethernet, as the customer had removed the ethernet protection (last week I might add).

If you look at the enclosure I posted, you'll see the 2 LSXL-MEs and the Citel. The MJ8 is grounded to a lug which is passed through to the enclosure. The LSXLs pass thru and the enclosure paint is stripped on the inside, and penetrox is applied on both sides of the o-ring, thus ensuring decent ampacity. Depending on the site, we may also pass a 2AWG conductor from another lug inside to a down conductor, though this is not common. All connection points including the lugs inside are penetroxed.

Ever tower is a bit different. On angle braced tower we normally use a Harger 213T flat plate to a bar if we have more than 2 connections, then all units are grounded via independent connections. Bonding to down conductors is always preferable if available. Code in the area, along with improved (and recent) tower regs, state that 2AWG is the minimum required conductor. Ribbon is also allowed as long as the correct minimums are observed.

In the past 5 years, we have had 2 lightning attributed failures on the 1000+ links we have installed and maintain. Those were an Orthogon Gemini and a Proxim 5054. The Gemini antenna and enclosure were melted. The 5054 was toasted via ethernet, as the customer had removed the ethernet protection (last week I might add).

Now why would a customer remove that piece, kinda funny. What kind of Cat cable do you use to supply the power and also what do you use to ground it and what protection are you using at the base of the tower for the PoE and in Building? I ask because I am fixing to setup a tower soon and I want to make sure I do what I need to do before i set it up. Any picitures you can take or diagrams you have would be appreciated.

Hehehe... guess he wanted to try his luck!

For short towers we typically use Comscope 5NF4, for taller sites, or where more normal grounding is required, Belden 7919A is used with shield clamps every 75'.

Hehehe... guess he wanted to try his luck!

For short towers we typically use Comscope 5NF4, for taller sites, or where more normal grounding is required, Belden 7919A is used with shield clamps every 75'.

What kind of shield clamp, btw, thanks for this info, it's very helpful.

When using 7919a, we normally use Times GK-S200TT midspan shield kits as they are the same size at the cat5 when stripped.

Can someone explain the difference between this two things:
Port to Port Isolation 30dB
Cross Polarization 25dBi
example from same antenna.

We have a lot of VERY GOOD links with PAC WIRELESS Dual Pol :

29 dbi and 32 dbi

You can use these antennas in 5.1 to 5.8 ghz, so you can make TX in 5.2 and RX with 5.7 for example...

We are using them with :

Mikrotik
Ubiquiti
Motorola OFDM
REDLINE
Etc...

http://www.pacwireless.com/products/HDDA5W.shtml

Regards

Same here.

5.7ghz 32 dbi MT myself

hi to all

i want to know for covering 1 mile denced area with Rb 433 ah+16 dBi omni antenna witch mini pci card required .and where can i bey it in India. pls help me friends.


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Fibrewire pls I need some more info from you;
You said your link is NLOS, pls give me the distance, height from the sea pwr out; I am starting to setup a 50km link that, at the center of it's travel, passes on top of a hill so it impact the fresnel zone; since 802.11n seems to be more suitable for NLOS connection on 5ghz I will try with a couple of SR71 and dual pol dishes.
Many thanks for your help
Regards
Alessandro

Can someone explain the difference between this two things:
Port to Port Isolation 30dB
Cross Polarization 25dBi
example from same antenna.

Port to port is in reference to the two antenna connectors on the radio card.

Cross polarization isolation refers to the perceived field strength when an E or H plane signal is compared to another E or H plane signal that is skewed 90 degrees. Thus if comparing a horizontal and vertically polarized signal being received at a remote location, the off skew signal will be reduced in power compared to the matching polarity signal.
What that delta is, depends on several variables, but the rule of thumb is 25-30db of difference on linearly polarized signals. (Circular and other multi-pole methods yield different results).

I have link with two MIMO r52N each point. I need to create nstreme dual link. For this link I have two multipolarized antennas.What is the best option?

Connect 1 radio in multipolarized antenna (each chain with one polarition) or connect each chain of 1 radio in diferents multipolarized antenna?

Thnks

Hello,

We will test 2x HDDA5W-32-DP with 4x XR5 radio cards on about 25km huge link this days, and I will post some test results here...

I have link with two MIMO r52N each point. I need to create nstreme dual link. For this link I have two multipolarized antennas.What is the best option?

Connect 1 radio in multipolarized antenna (each chain with one polarition) or connect each chain of 1 radio in diferents multipolarized antenna?

Thnks

One radio, one antenna, otherwise you will create too much interference between channels..i.e. 2 channels on the same antenna...

Hello,

We will test 2x HDDA5W-32-DP with 4x XR5 radio cards on about 25km huge link this days, and I will post some test results here...

did you test these, and are they worth the $380+ each?

Sam

Port to port is in reference to the two antenna connectors on the radio card.

Cross polarization isolation refers to the perceived field strength when an E or H plane signal is compared to another E or H plane signal that is skewed 90 degrees. Thus if comparing a horizontal and vertically polarized signal being received at a remote location, the off skew signal will be reduced in power compared to the matching polarity signal.
What that delta is, depends on several variables, but the rule of thumb is 25-30db of difference on linearly polarized signals. (Circular and other multi-pole methods yield different results).

Dear Matt,
So sorry, I'm new to this. Base on your explanation, could you give the sample of the picture from what you've described.
I think this could give a better view on this.

Another question, is there a different between cross polarization and dual-polarization?
Is the dual-pol same with the dual-band antenna?
For the N card type which got 2 connector for antenna, is cross polarization best for any wireless networking or dual-pol?

Thanks

Dear Matt,
So sorry, I'm new to this. Base on your explanation, could you give the sample of the picture from what you've described.
I think this could give a better view on this.

Another question, is there a different between cross polarization and dual-polarization?
Is the dual-pol same with the dual-band antenna?
For the N card type which got 2 connector for antenna, is cross polarization best for any wireless networking or dual-pol?

Thanks

I'm not sure what you're asking for exactly regarding a better description or picture.

Cross polarization is just that, two signal with differing polarities, normally 'crossed' if they are planar. You can also have cross polarity by using right and left hand circular.

Dual polarization is anything using more than one polarity, whether a planar and circular, two planars with one skewed, or even two of the same polarity, thus inferring spatial diversity.

Dual band refers to different frequency ranges, such as 2.4 and 5.8ghz.

Depending on your system design, dual polarity may be sufficient, or cross polar may be desirable. This gets into design considerations of your base and client.

Hello,

I'm just testing 2 x ITELITE DP 16dB
RB433 + 2x CM9
Distance about 400 meters...

Dual n-stream max 3/3 Mbps ????

I have other 2 dual n-stream links with 2 antennas per side and works about 25/25 Mbps on 6-7 km distance (conf is RB433AH + R52H)...

To anyone using dual polarity SECTOR antennas with an access point (not dishes for ptp)! How are you connecting it? Do you use one radio per polarization like 1 radio for horizontal and one radio for vertical or are you using one radio and splitting the signal to the dual n connectors on the sector?

Is anyone using dual polarity sectors antenna at their base station? If so, what manufacturer and model used?

Yes, we are using 16dbi vert/ 16dbi horz dual pol 90 degree sectors. They seem to be performing well although I have not tested them extensively. We have many installations with 4 sectors installed giving 360 degrees coverage in horz and vert.

I am buying them here. http://www.irishwireless.eu/shop/item.aspx?itemid=270
I think that they are made by ITElite.

To anyone using dual polarity SECTOR antennas with an access point (not dishes for ptp)! How are you connecting it? Do you use one radio per polarization like 1 radio for horizontal and one radio for vertical or are you using one radio and splitting the signal to the dual n connectors on the sector?

How about the simple approach: using both chains on a 802.11n radio?

Poynting's dual-pol 5Ghz enclosure/antenna has worked great for us. An RB600 fits inside.

Ditto this. We have good luck with the Poynting case + 600 + R52hn over short distances (under 5 miles). We have achieved just shy of 90mbit with two 600 boards stripped down (necessary packages only, connection tracking off) over these links, which mates very nicely with a DS3 landline. On longer shots we've used Pac Wireless' 32db dual-pol dish with radome and achieved 70+mbit out to about 20 miles.

Both of these antenna are dual-pole, zero separation units, relatively compact and convenient to deploy. I suspect that there is greater performance to be gained with spacial separation as well as different geometries in the antenna array, but as our performance results have always been faster than our landline uplinks we haven't had to put any additional labor in. We are, however, very interested in the results of others using spacially separated antenna and how their results compare.

-Nelson

Hello,

We will test 2x HDDA5W-32-DP with 4x XR5 radio cards on about 25km huge link this days, and I will post some test results here...

did you test these, and are they worth the $380+ each?

Sam

Yes, see my post above.

-Nelson

I am looking to do a channel modeling study in 400MHz in an NLOS environment and hence looking at the following options for base station antennas which can deal with multipath:
- circ polarization
- dual polarization +/- 45degrees
- And I have also thinking about do a 2-separate antenna solution, one V and one H yagi going into a single ant connector through a power combiner / splitter.

Any thoughts on choosing the right approach?

your comments appreciated.

sid