Looking for best low-cost USB/4G modem to transfer CAN data from car to cloud

[Martin F]

Hi there,
I'm logging data from my car to an sd card using a wifi CAN Logger.
The logger can use FTP push to push the data to a server while on-the-go.

However, rather than having the logger connect to my mobile phone hotspot to access the internet, I'd like to use a separate USB 4G modem to act as the access.

Do any of you have good suggestions for low cost modems that are still reasonably stable?
The data to be transferred would probably be around a GB per day, broken into chunks (e.g. 50 my per log file to be transferred).

Thanks!

[stmdude]

For a one-off?

I'd use an old Android phone, and have it do USB tethering. Shows up on the host as an CDC Ethernet device and provides DHCP+NAT.

[Martin F]

Ideally it would be a solution that could work at scale, i.e. initially it would be a one off for testing, but over time we would consider something that could be used across e.g. 20 vehicles.

[logictom]

I've used Telit modems, an HE910, 3G, and LE910 LTE Cat 1 - they are 38 and 36 USD in 180 quantity, not sure about single price, that also for the Aus version. They have a serial or USB interface. They can be bought as a BGA or they come as a mini PCIe module (increased price), which has a USB interface. They do also sell a version in a little extruded aluminium case with power and USB.
I've heard good things about ublox devices, I believe they are cheaper than Telit units, not sure about USB though.

Depending on whats running on the logger, what about an off the shelf USB 4G dongle from any of the main telcos?

[Martin F]

Thanks a lot for a good response !

Essentially, a 4G dongle as you describe could work - and if you know some good ones it may be relevant to test for us. But what we are looking for is something that is ideally "unlocked" to allow other users to install their own SIM cards, assuming e.g. a company has a cellular plan already in place with a supplier they would like to use.

But with that in mind, we are looking for the cheapest possible solution, while maintaining an OK reliable connection. And ideally as compact as possible.

Thanks again,
Martin

[woody]

LoRaWAN?

Missed the Gb/day 

[logictom]

LoRa is used for bytes and kilobytes, you'd never get a GB out a day over LoRa.

You haven't stated what cheap is but you're unlikely to get cheap, small and unlocked.
If you don't want to layout a board then something off the shelf will have to do,  you haven't stated your country so what may be available here probably won't be there.
If you only want 20 and cheap I would look at cheap phones as mentioned earlier.

[Martin F]

Sorry for being unclear:
- I'm looking for options first of all for Denmark/Europe - but over time potentially also alternatives that can work for e.g. USA and rest of World
- The aim is to offer a solution for fleets (trucks, cabs, ...) which means that it could vary in numbers (from e.g. 20 to 100+)
- I'm looking for something that is fairly simple to set up and doesn't take up too much space in the cabin, hence the small / compact
- It would be offered as part of a packaged solution that does not involve too much effort on the client side, hence an old phone e.g. would not be ideal

Hope this clarifies - again thanks a ton,
Martin

[rt]

Martin,

Have you looked at the simple USB powered Mifi modules:
e.g. https://www.aliexpress.com/item/New-Similar-with-E355-14-4Mbps-Portable-Pocket-Mobile-Mifi-Mini-Wireless-USB-Hotspot-3G-4G/1875161052.html

Configured over Wifi Admin panel and have >10m range indoors.  We use them for similar applications to yours.  Loggers which kick data up to a server over http.

rt

[Martin F]

Good tip, I'll check those out!

[krho]

Have you looked what if anything that ublox has suits your need? They are also probably cheaper and more avaialbel in EU than the ones from Quectel.

[logictom]

That helps.
Couple of things that I've had to pick up of late as we are trying to get a product ready for US sale.

In the US if you use a module, even a FCC approved and PTCRB PCB based approved module, like a Telit or ublox, you still have to put it through testing, just not the full suite as if it was an unapproved module - read $$$

So for low cost I would advise something USB based if possible.
Something else to look at is would you go for a single module with worldwide coverage or buy region specific modems? Region specific are cheaper, fewer bands, but you have to stock multiple lines. I'm not sure about other modules but with Telit, for the US, you get the AT&T or Verizon one (I think that's correct - I'll double check).

How will you handle the user entering information into the module? The main one being the APN. If you're going to allow them to use their own SIM on any network then you need a system in place to set this up. Alternatively you could limit to a given provider in each region and preset the details.

Sierra wireless offer a SIM which will work worldwide and roam across networks for a fixed fee - not sure what that fee is though.

I'll find some details on the USB module we use hooked up to a PC.

[logictom]

This is the modem I was referring to, not sure on pricing but you can probably find it, or similar online. Price per unit is probably a lot higher but overall, with low volume, it might be your best bet.