The BIG and SMALL ANTENNA topic part 1

no problemo I think :wink:

Well that didn’t take long…

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The local pigeons have decided they like their new 3dBi perch!

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LOL :sunglasses:

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11 dbi and 13 dbi:roll_eyes:

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nice story from Garry https://www.thethingsnetwork.org/community/dublin/post/a-popular-gateway-upgrade

Thanks BoRRoZ! Finally got the gateway and outdoor antenna permanently installed so the antenna experts here may advise about how effective the shield on the rear of my TV’s array antenna will be for blocking LoRa to my new 3dBi antenna? Should I lower the array below my LoRa antenna for better omni-directional?

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Does this antenna/gateway combo work? Well yes, I have received packets from just over 15km but from high ground, it is not totally flat around my house. I used my home made 1/4 wave ground plane from the @lex_ph2lb design on a Pro-Mini node with RFM95W radio but didn’t hang around long enough to try other antennas on my node. I have however seen over 5km with one of those tiny 50mm long sma antennas so next testing is to see how close to the ground I can reliably place my node without attenuating too much RF energy.

Garry

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I think its always better when an omnidirectional antenna, like the one you have installed, is ‘free’ all around so no reflection/blocking/attenuation ect. … but to climb on the roof immediate… take your time to expiriment a bit and watch your console / application

We’ve been using these $30 antennas and they work fine. We get 6 miles distance. Here is a picture of a gateway and antenna installed on the roof of a local winery in Temecula, California.IMG_3838

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I am curious to know if you have to be careful with node placement, specifically height over ground? One application we’re lookig at has the nodes on or effectively just below the ground! Not much data yet.
Thx, G

antenna should be above ground with the sensors underground if you need some distance.

sensorglobe_agriculture_iot_1

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The city I live in has LoRa sensors in manholes. Since the manhole can be in the middle of the street, the antenna needs to be placed underground. They have limited the distance to nearest gateway to 500m, and they report that works.

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yes it works, like for example parking sensors… but limited distance

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Typically, we need to have line of sight connections. Higher is better, also because of the earth’s surface curvature. Our units are installed above the canopy of grape vines. Trees and crops attenuate the signal at 900 MHz, a lower operating frequency would have been better for agricultural applications.

Because we have hills here, we cannot always get line of sight and need multiple gateways. The small femto gateways that are coming out seem ideal for that.
We have one station that has no line of sight, it’s behind a hill, but reflects off a nearby mountain to get the signal to the gateway. Reflection is likely how the signal still can get some distance from a manhole.

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Hi BoRRoZ
Do you have any results with these yagi antennas?
I ordered parts for yagi antenna from local hardware store. Unfortunately I dont have enough time to build and test it.

I’ve had the 11 dbi connected a while ago but I didn’t test the 13 db yet, that one have more elements (duh) but the overall length is shorter

so if you have stationary node(s) in a field far away …

I had good range results with this type of Yagi directional antenna too. It was available on Amazon for $30, and I’ve seen many similar offerings. Data sheet gain is around 10dB.
I like the fact that the antenna is in an enclosure, keeping rain and ice away which can detune . Not that we have that problem in Southern California BTW.

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never seen before… enclosed small yagi … and affordable :sunglasses:

Here are some links, noticed price has gone up a bit since last year.
http://a.co/fmCc95g
http://a.co/4nWyM7h

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Even lower cost here: http://a.co/hXipO6H