Signal Plus 15” LoRa Antenna
The Signal Plus 15” omnidirectional LoRa antenna offers fantastic performance for mesh applications in the ISM band.
Of all antennas I’ve used for LoRa/mesh purposes, this is (by far) the antenna I’ve spent the most hours testing various equipment and firmware with, and for good reason. It is simply an excellent antenna.
Pictured on the right, you can see one of the my permanently-mounted 15” Signal Plus LoRa antennas is on my main test vehicle (a suspiciously-overpowered electric golf cart).
About this Antenna
There’s nothing really LoRa-specific about this antenna (or any others that I’m aware of), except for the fact that it’s sensitive to the range of frequencies typically used for mesh and LoRa systems.
Specs
Cost (2025): $32.00
Frequency: 824.0 - 960.0
Gain: 5.8dBi
Height: 15”
Type: Omnidirectional
Max Power: 150 watts
Weatherproof: Yes
What’s Included
Antenna
Mounting Bracket (attached)
3 Meters of pretty decent cable
U-Bolts for attachment to a mast
Mesh / LoRa Antenna Tests
Methodology
As a mesh communication firmware developer, my only interest is really whether this antenna plays well with LoRa mesh applications. My testing is pragmatic and focuses on reliability of encrypted mesh deliveries (one way and 2 way) at various distances, and that is really all.
As you can see in the screenshots below, using the ChatterBox mesh firmware, I’m able to see a live view of which devices/nodes I’m receiving pings from. I’m also able to send messages, which return an ECDSA signed confirmation (shows as check mark), so I know for a fact the message was received and validated, without seeing the distant device.
At first glance, this may not seem like an antenna you’d want to mount to a vehicle, but to run through the variety of tests I had planned, the easiest solution was to mount it to my main short-range test vehicle (shown here).
Vehicle Mounted Testing
Generally, I’m only interested in single-hop ranges up to 15 miles or so, so this electric test vehicle works fine for that. For distances greater than 15 miles, I’d rather the mesh firmware handle routing than have to be running amps in multiple places. But, that’s a personal preference really.
Mounting and running at a stationary position (base station) is how I image most people would make use of this particular antenna.
Given that it’s weatherproof and ready to be mounted to the side of a wall or to a mast, I think that’s what you’re most likely to do if you’re reading this.
Stationary Node Testing
The ChatterBox mesh communication firmware is designed to learn and take advantage of the fact that some mesh devices are moving around while others are stationary. Stationary nodes/devices typically have fairly constant connectivity (or lack thereof) to other stationary nodes, while ones that move a lot (say, in your vehicle or pocket) make good opportunistic delivery “nodes”, but shouldn’t be counted on quite as much as stationary nodes.
Findings
Typically I focus on a few common pairings of antennas to test with, and the standard battery of tests are a range between 1 and 8 miles. At 8 miles and beyond, earth curvature plays a factor and requires more height (at least here in the flat midwest). If an antenna is looking really promising, I’ll push the distance a little more…but again, the focus of my testing is mesh firmware compatibility, not breaking RF records.
Pushing The Limits - 26 Miles in 1 Hop
I cannot predict how well you’d be able to replicate results, because certainly there are many factors involved that can significantly impact over large distances and often change with the seasons/weather/terrain.
With the above caveat out of the way, I can tell you I’ve successfully (and repeatedly) send encrypted messages and received signed confirmation within seconds, and in one hop, over distances as high as 26 miles.
This was not via multiple mesh hops, but rather direct RF in a single hop. Given that there were no mountains (this is the flat midwest) and the 15” signal plus was only about 8 feet off the ground…I was pretty blown away by this one.
With the ChatterBox firmware, that means this antenna / equipment was able to exchange 12 packets bi-directional on at least 6 different frequencies across 26 miles within a few seconds…simply amazing.
Rating : Excellent - Highly Recommended
The Signal Plus 15” Omni antenna offers excellent performance for mesh / LoRa systems. It has become the go to antenna for ChatterBox solar nodes and fixed-position nodes where wind and space could be a concern.
At $30-ish, the value offered by this antenna from Signal Plus is just outrageous. You are not likely to find anything near this price that compares in any way (if you do, please contact me).
You may notice there’s a coat of black latex paint on the antenna mounted to the test vehicle. That had no noticeable affect on performance at all, making this a decent stealth option as well.
I regularly run these antennas un-amped, paired with 1 watt and 20 watt amps with excellent results in all cases. If you pair a 20 watt amp with this thing, prepare to be amazed.
For anyone who wants a fixed antenna that isn’t so big it’s an eye sore, this LoRa antenna is my top recommendation.