Best equipment for long-distance 2.4 GHz link?

I should have said the other side is not my actual office but part of my workplace. I wanted to avoid opening the administratively non-trivial request of installing a new access point for my home office, and it seems with my present equipment I am just at the edge. It seems to me a router with good signal processing and a decent antenna would do the job. So - which ones?

routers... both sides need dedicated directional treatment. a home made parabola reflector(s) would get you 200m... albeit at %30-50 goodput primarily due to latency.

yaghi sounds optimal

Maybe without much administrative hassle one of the existing AP's could be moved closer to a window facing your house. As you said, you only need a few dB here.

If there is 5 GHz I'd use that as more antenna gain is possible in a small package and there is less interference.

I've never had any success with yagi antennas on 2.4. The "best equipment" here clearly would be a dish, so with that ruled out you're looking for second best, which I would consider some sort of CPE. The one TP-Link CPE that I have used, granted it was an old model, had absolutely terrible radio performance compared to anything Ubiquiti.

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Since I already have iffy connectivity, I don't think I need a directional antenna on the other end. I'm sure it would help, though.

Good point about moving the AP - I will check into this. The net is only 2.4 GHz.

Based on your comments, I checked deeper into Ubiquiti. I see UAP-AC-M ("UniFi Access Point AC Mesh | 2.4 / 5 GHz") and think about using it with the external antenna AM-2G15-120 ("Ubiquiti AM-2G15-120 | 2.4 GHz, airMAX Sektor Antenne, 120°, 15dBi"). That would probably get me the extra few dB, based on your comments. The AP looks like is is supported by stock OpenWRT. I will think about ordering this equipment.

https://comfastwifi.us/comfast-cf-e314-outdoor-cpe-bridge-long-range-300m-signal-booster-extender

not tried it personally but i have tried their 5ghz model. (model cf-e312a)
cost about around 44 usd.
tested on a mobile phone with 5ghz and i get full speed on my 50mbps dsl.
LOS at around 250meters.

After some searching, there are a few access points (that I would run in client mode) with integrated antennas that look like they may have a higher gain antenna than the 9db antenna of the TP-Link CPE210 with which I have had partial success. I see:

  • MikroTik SXTsq Lite2 (10 db antenna, about 35 EUR),
  • LigoWave LigoDLB 2-14n (14 db antenna, about 100 EUR, but seemingly not available in Germany)
  • Ubiquiti Nanobeam NBE-M2-13 (13 db antenna, about 95 EUR).

Unfortunately, it doesn't look like there is a stock OpenWRT image for any of these. Am I missing any device with support in stock OpenWRT images? For the MikroTik, it looks like it would be fairly easy to build an OpenWRT image. For the Uniquiti Nanobeam, it also looks like it might be possible.

My other option maybe be something like an ALFA Tube-2HP (65 EUR) as client/AP and a YAGI antenna with 12 db or 16 db gain (about 30 EUR). This would come with good OpenWRT support.

Any comments on this?

The Comfast CF-E314NV2 has a 14 db antenna and looks like it would be sent from outside Germany and would take a while and have questionable return possibilities and would cost about 50 EUR. It is not listed as having a stock OpenWRT image, although there are several other Comfast devices with support, so probably would be possible.

http://downloads.openwrt.org/snapshots/targets/ath79/generic/openwrt-ath79-generic-comfast_cf-e314n-v2-squashfs-sysupgrade.bin

if you need a higher dbi ubiquity has many models but would cost much more.

the mikrotik LHG 2 xl is the best option, in 2.4 ghz, that is not listed as supported but i'm sure it will work, i wish i have one, that is missing from my collection.
another option is the old stable ubiquiti powerbeam m2.
LHG = 21dbi antenna
ubiquiti powerbeam = 18 dbi antenna

Not sure why this feed showed up with an alert in my email, as I am not part of it, but since i am here anyway:

  • The NanoBeam are supurb little devices. Running 3 pairs of them myself, with trees; 150~250 meters)

  • Ideally, you should have them at both sides, in pairs. If you run them in reverse, so the Office side as STA-client, your home as AP, you are strictly speaking not setting up an extra AP. (and if you do it sneakily, they will not detect an extra AP.)

  • Stock OpenWRT for Mx series (XW variant https://openwrt.org/toh/ubiquiti/nanobeam) will run on this device. But do remember to downgrade to older Ubiquity first, or you are bricking it and need to open up the device to hardwire it to serial. And these NanoBeams are ultrasonicly welded, cannot be opened up without a dremel.

  • Why run OpenWrt at all. Especially if you use them in pairs, the native AirMax TDMA mode is best for completely transparent links (do choose the WDS mode on both sides, even if you are not really repeating, so it activate MAC & ARP transparency)

  • Nowadays, I would prefer 5Ghz, especially if you deploy them in pairs. So the NanoBeam 5AC-16 or 19 instead.

Best of luck

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Thanks for all the feedback.

I ordered the Ubiquiti NanoBeam M2-13 and matching indoor suction-cup window mount. I'll report back once I've had a chance to try it out. Meanwhile, I will try to get my colleagues to move an AP closer to a window.

My Ubiquity PowerBeam PBE-M2-400 easily connects to a router 4 miles away with clear LoS

yes, it's a super machine.

The main problem with the urban WiFi links on the 2.4 GHz band is the interference. I would suggest 5 GHz devices for similar projects. Nevertheless, I hope you find some free spectrum for your link using the aforementioned equipment. :slight_smile:

For those without the spare cash but some mechanical skills there is the "cantenna" which used to be well known a few years back.
If you search the web for cantenna multiple useful links will be returned.
For example:


or
https://www.turnpoint.net/wireless/cantennahowto.html

So with the Ubiquiti NanoBeam M2-13, my connection now is pretty decent and meets my needs, although not quite as strong and robust as I would ideally like.

I suspect the improvement is mostly due to the overall improved antenna and signal processing of the NanoBeam compared to the TP-Link CPE210 I was trying with before. However, I have also been experimenting quite a lot with positioning and aiming the device, and this has likely also improved a little bit, so this is not a perfectly controlled comparison.

This connection is now stable for hours albeit at relatively low rates - typically MCS3 is the highest negotiated. The connection does occasionally briefly drop out, but so far this was only happened a couple times for a few seconds, and this is not problematic for my use case. I suspect a Ubiquiti PowerBeam M2-400 (or a MikroTik LHG 2) would indeed give me a better connection but, as I said, our landlord does not allow mounting a dish, so I have stayed away from those. (And hopefully the NanoBeam is inconspicuous enough that it does not count...)

Thanks for all the advice on this thread!

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