The YoctoHub-GSM-4G is a wireless-enabled module that can host three Yoctopuce modules to access them remotely through a 4G (LTE-M or NB-IoT) or 2G cellular network. It can be powered either by a Micro-B USB cable and a regular phone charger, or a 5V battery pack.

For 4G, the YoctoHub-GSM-4G works on LTE bands 2, 3, 4, 5, 8, 12, 13 and 20 in LTE-M (LTE Cat M1) and NB-IoT (LTE Cat NB1) modes. For 2G, the YoctoHub-GSM-4G works on GSM bands 850 MHz, E-GSM 900 MHz,
DCS 1800 MHz and PCS 1900 MHz (quad band), in GPRS and EGPRS (EDGE) modes. For a detailed list of supported frequency bands by country, consult the Wikipedia pages https://en.wikipedia.org/wiki/LTE_frequency_bands and http://en.wikipedia.org/wiki/GSM_frequency_bands. Note that some countries have not yet deployed LTE-M and/or NB-IoT support.

You can use the YoctoHub-GSM-4G in the same way as a VirtualHub running on a little computer, but it is much easier to setup and maintain than a computer. It is smaller and consumes less. It is compatible out-of-the-box with all existing applications using Yoctopuce API. As for the VirtualHub, it can run autonomously using HTTP callbacks.

Moreover, the YoctoHub-GSM-4G features a built-in clock timer, that makes it possible to put the device into low-power deep sleep and wake-up automatically at predefined times. This makes it possible to reduce power consumption to 15uA while sleeping, which is crucial for applications running on battery or solar panels. The YoctoHub-GSM-4G only needs a few seconds of wake-up time to post data on an web server using the HTTP callback.

You can connect three Yoctopuce modules directly, one of which can be fixed directly on the YoctoHub-GSM-4G and connected using a Board2Board-127 connector. More devices can be connected, thanks to the YoctoHub-Shield extension. The YoctoHub-GSM-4G can power Yoctopuce devices up to 2A.

The device is provided with an articulated antenna (9cm, with SMA connector) and a connection cable (uFL to SMA).

Warning: although the 3 downstream ports hosting Yoctopuce devices use micro-B USB connectors, the YoctoHub-GSM-4G uses a specific protocol simpler than USB to talk to the devices. Therefore, it is not possible to drive or even to power a regular (non-Yoctopuce) device using the YoctoHub-GSM-4G. It is not possible either to use a regular USB hub (such as the Micro-USB-Hub) on the downstream ports. If you need more downstream ports for Yoctopuce devices, you can use a YoctoHub-Shield.