Where the is a WISP there is a way

While driving to #usmum2019 I happened to see this lone antenna sticking up on a house off of I30 near Dallas.  Being a “WISP guy” I am probably just a handful of folks who recognize such things.  If you are a wisp and think you can’t compete in urban areas remember this picture.

Now, I do not know the details. There could be zero broadband in this neighborhood, or there could be a lot of competition.  If any of my readers claim this please let me know the details as I would like to do a story on you. Wireless ISPs can compete and are competing everyday.

PTP 550 continuation

In a previous post, I mentioned a 5-mile link using Cambium PTP550s and why frequency matters. Today we enabled the second radio and have some results from that.  First, let us talk about some of the parameters.

As you can see from our frequency scan we have a very noisy frequency.  Without DFS we have very few open channels.  Due to this, the results you will see later are not optimal.  The limiting factor is the noise on the band.

After much channel selection, this is what we ended up with. As you can see we are just running a 40mhz and a 20mhz channel.  This is because the band is so noisy.

As a result of the frequency, this is what we have ended up with for quality and capacity. The second radio is less than optimal, but it is passing solid data.

So what do speed tests look like across the link?

Single Radio Speedtest

Using channel bonding

Some of you may still be asking, it should be more. If you have noticed the noisy frequency band has been the greatest factor on this link.  In the quality and capacity screenshot, you will notice the 2nd radio only has a 45% capacity.  This is due to channel selection. If we could get better channels this would improve the link.

Wo what is the answer? Better backhaul antennas are upgrade number 1.  Currently, we are using UBNT 2 foot dishes, which were chosen due to the gain needed on this link. Secondly, when DFS is certified for these radios we will have more channels available.  The frequency scan shows the DFS channels are less noisy in this area, which will increase throughput.

Just for giggles, we had the tech on-site run a speedtest.  This was through a wireless router with a 100 meg ethernet port plugged into the local router.

 

Frequency does matter

Recently we installed a PTP 550 link for a client.  This is a connectorized version with 2-foot dishes on it for a four-mile link.  Overkill you say, but the idea is the dishes make up the gain and not transmitter power.  A much cleaner signal can be achieved which falls within the FCC guidelines for total EIRP.

So let’s get to it.  Our first image is out path.  This link had clear line of sight from a 150-foot foot water tower to a 240-foot tower.

Google Earth Path

The 240 Foot tower

150 Foot water tower

After getting out of the cold we let things burn in for a few days. This is what an initial spectrum analysis looked like.

Radio Frequency set on 5820 mhz

Radio Frequency set on 5200mhz

As you can see the RSSI was within 2 DB, which isn’t terrible.  However, due to interference, the MCS rates are markedly different, which is what results in the big differences in speed.  Please note this is only with one radio enabled and on a 20mhz channel.  We fully expect bigger speeds once we up channel sizes and enable the second radio.