Recommendation for a antenna upgrade, or signal booster?

Hardware
1

Greetings Particle community.

I’m working in remote parts of East Africa (currently Tanzania), using Electrons to monitor/control off-grid solar energy systems. A lot of the places we work in now (and intend to go) lack a decently strong/reliable signal. I’ve been using 3rd Party SIMs with some success, since the Particle SIM carrier doesn’t have a strong presence here, but even the strongest local networks aren’t quite strong enough.

I’m wondering if anyone has had some success with range extenders, signal boosters, or even just alternative antenna with an electron in a location with a consistently weak signal.

2

Hi @SCM,

Good question! In an area with less cellular coverage, you can improve your signal using a antenna with better gain, or a directional antenna. Checkout some of the more powerful Taoglas antennas here, and physically getting some altitude on the antenna can help too.

https://www.digikey.com/catalog/en/partgroup/taoglas-limited-external/22473?mpart=GSA.8841.A.105111&vendor=931

Look for higher decibel gains (dBi’s), and sometimes just moving the antenna around, trying to orient it towards a known tower can help.

I hope that helps!

Thanks,
David

1 Like
3

However, using a higher gain antenna than that specified in the Electron certification will require new certification to local standards.

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4

Please do update us on what you end up doing about this.

I also plan on deploying web-connected solar generators in Africa in the future. Have not dealt with cellular networks over there yet.

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5

Thanks for the tips. What do you think about this? https://www.digikey.com/product-detail/en/abracon-llc/APAMS-131/535-12921-ND/5226442

Also, is using a 2 band (matched to the U-BLOX 270 frequencies) going to give me better signal than a 5 band antenna that works with either the 270 or 260?

6

Hi @SCM,

In particular you want the gain to be in the frequency bands you’ll be using, so a quad-band antenna isn’t necessarily better for this particular project unless you’re using those extra bands, but it might help if you wanted to re-use that antenna for something else down the road. I would (depending if you’re using 2G, or 3G), lookup the local frequency bands, and pick an antenna with good performance / efficiency in that range.

Thanks,
David

7

Thanks @Dave

I just ordered a few to test, will report back here to let people know what I find out.

1 Like
8

So I ordered the following two antennas for testing:

https://www.digikey.ca/product-detail/en/abracon-llc/APAMS-131/535-12921-ND/5226442

https://www.digikey.ca/product-detail/en/abracon-llc/APAMS-103/535-12093-ND/4155858

So far I’ve had no luck with either of them. I’ve been testing in a location with weak 3G signal that comes and goes, but the EDGE network is pretty persistent.

I can connect with the standard Particle taoglas antenna. I’ll paste the output from the Particle test below. With the above antennas I’m trying to test, the +UEONS command rarely returns any of the networks that Particle antenna finds.

UPDATE: I wanted to note that I’m using a test program written by @rickkas7 found here: https://github.com/rickkas7/CellularHelper

TEST OUTPUT:

Turning on uBlox modem...
Cellular.on() took 480 ms to run
manufacturer=u-blox
model=SARA-U270
firmware version=23.20
ordering code=SARA-U270-00S-00
IMEI=***********************
IMSI=***********************
ICCID=***********************
----------------------------------
Now getting network registration status
----------------------------------
--------------------------------------------------
----> Sending command: AT+CREG?


+CREG: 0,1

OK
----------------------------------
Now trying to get a list of all the carriers that the modem can see
----------------------------------
--------------------------------------------------
----> Sending command: AT+UEONS

+UEONS: (2,"ZANTEL-TZ","ZANTEL","64003",2,"",""),(2,"ZANTEL-TZ","ZANTEL","64003",0,"",""),(3,"64009","64009","64009",2,"",""),(1,"TIGO - TZ","TIGO","64002",2,"",""),(1,"TIGO - TZ","TIGO","64002",0,"",""),(3,"64009","64009","64009",0,"",""),(1,"64007","64007","64007",2,"",""),(3,"celtel","celtel","64005",0,"",""),(3,"VodaCom","VodaCom","64004",0,"","")
OK
----------------------------------
Now trying to get an IP address!
----------------------------------
Got an IP address in 2290 milliseconds
running cellular tests
operator name= Zantel
rssi=6, qual=2
service rat=UMTS mcc=640, mnc=3, lac=e8 ci=158913 band=UMTS 2100 dlf=10662 ulf=9712
ping 8.8.8.8=1
dns device.spark.io=0.0.0.0
attempting to connect to the Particle cloud...
connected to the cloud in 18920 milliseconds
running cloud tests
tests complete!
press the MODE button to disconnect from the cloud and repeat tests
------------------------------------------
END OF TEST OUTPUT
9

Here is what I get with the APAMS-131:

Turning on uBlox modem...
Cellular.on() took 480 ms to run
manufacturer=u-blox
model=SARA-U270
firmware version=23.20
ordering code=SARA-U270-00S-00
IMEI=***********************
IMSI=***********************
ICCID=***********************
----------------------------------
Now getting network registration status
----------------------------------
--------------------------------------------------
----> Sending command: AT+CREG?


+CREG: 2,0

OK
----------------------------------
Now trying to get a list of all the carriers that the modem can see
----------------------------------
--------------------------------------------------
----> Sending command: AT+UEONS


OK
----------------------------------
Now trying to get an IP address!
----------------------------------

Then the test hangs up while looking for an IP address, since it didn’t seem to find any cell towers.

Am I missing something here? Shouldn’t these antennas work?

10

How are these antennas powered?
AFAIK active antennas need to be powered :confused:

11

@ScruffR I’m not powering them with anything other than what is supplied by the Particle’s antenna connector. Is there a way I could inject more power?

12

I don’t think the Electron supports active antennas that aren’t selfpowered.
@mohit might have some insight tho’

13

One of the reasons I chose those antennas was because it seemed like they were self powered. At least I don’t see anything about power supply on the data sheets. Was I wrong? :grimacing:

14

The keyword is “active”.
How would the active circuitry work without supply power?

15

The antenna datasheet says nothing about powering the antennas or power specs so I also assume they are not powered.

I found this though:

image.jpg1946×1288 197 KB

16

The specs are confusing. One is called “active” with no power specs as @ScruffR indicated and the other is clearly passive. However with 3dBi and 2dBi gain, I suspect as @ScruffR pointed out, that neither is active.

17

:blush: I seem to have misinterpreted this table

image.png804×1000 55.2 KB

Only looking at the “value” and not at the whole row is no good :flushed:

2 Likes
18

So it seems like these are indeed passive antennas. Any ideas for other tests I can perform?