No that is not possible. The device would need to operate as a gateway and that is not simple.

Hey Charliemaker,

Cellular-based Gateway - This is something that you can do today if you wish! We have some users who have used a cellular modem connected to an mc-Gateway (Either through Ehternet or WIFI) and then can relay the information from their modules via the gateway and then to the cloud using cellular connectivity. You would need to source a cellular modem/cellular hotspot to do so but it is relatively easy to do! Something like this would work: http://nimbelink.com/e2c-link-ethernet-to-cellular-router/

can someone recommend a low-cost device that would serve as an interface between the mc-Gateway and SIGFOX network?

What are you looking to do? If you look at mc-Demo205, you can relay the information back to the cloud using the SIGFOX network quite easily (providing you are within SIFGOX coverage). The mc-Demo205 is quite a versatile device and can connect to multiple sensors or devices and also includes a built-in temperature sensor, accelerometer and boasts a GNSS receiver too! Depending on what you are wanting to do, the 205 could be a good choice as you can measure multiple variables and relay that info via SIGFOX. If you are interested in learning more about the mc-Demo205, you can check out:

mc-Demo205 product specification: https://static1.squarespace.com/static/5644f11fe4b0d6ca7d80d351/t/582f8781e4fcb5e251bc00a4/1479509893678/mcDemo205+Product+Specification+V0.3.pdf

YouTube video - Technical overview of the mc-Demo205