Sigfox is a LPWA network using the free radio frequency to communicate. There radio frequencies are changing in the different zone (Europe, America, Asia…) When you are developing a device you need to test it but you are not authorized to use all these frequency from the country you are.

The Sigfox emulator is a solution for this : it allows to directly connect your device and analyze the transmission whatever the frequency you are using is. The Sigfox emulator kit is an SDR dongle with a Sigfox software for understanding, decoding the sigfox signals.

You can wire your transmitter to this receiver to not emit the signal over-the-air and legally use a non authorized frequency in your country. When you are using an authorized frequency you can simply communicate over the air.

Kit

The kit contains:

• The SDR kit you can connect to a USB slot.
• 2 antenna wires with a SMA connector and an UFL connector.
• A 40db attenuator you can add on the line to avoid receiver saturation.

Installation

The kit comes with a link to the software download. This software works on Windows 10 and Linux. Documentation indicates W7 also supported.

You need to plug the dongle in one of the usb and wait for the driver installation. Once done you can run the Snek program you downloaded from sigfox.

Then this is a standard installation :

One done the program named SNEK is accessible. To start it you need to have the sigfox dongle connected. In my experience (running on a VM) the USB device is named NXPxxxx and then its name after a certain time changes to Sigfox NED. Only when you have this second name is appearing you can connect and start the SNEK.

Configuration

The configuration is made from a web page connecting to the emulator server. During my test with the default IE browser on W10 it was not possible to save the page setting but in fact it seems doing it… By-the-way a switch to chrome solved that.

The setting url is : http://localhost:8085/static/index.html

The first step is to select the zone you want to listen to

The you set the device ID you want to receive and decode.

Configure the device

To be received by the Snek tool the device must be configured in emulator mode. This is a way to distinguish the test messages from real messages (and also a way to not use the SNEK as a Sigfox sniffer). This is made by switch the device private key to the Sigfox public key.

By-the-way, with a TD device you can switch to this mode with an AT command:

AT$PID=1

When you modify your firmware you can do the equivalent configuration calling the following function before any transmission:

TD_SIGFOX_SetPublicKey(true);

This function has to be called before the Sigfox transmission. Once is sufficient until the next chip restart.

Listen for messages

Now the messages can be received clicking on the “Message” entry menu on to of the Page (This entry can be hide behind the Authentication enabled label when the window is not full page)

Once you fired a message from the device you can get it on the emulator windows. The tool is also able to simulate a callback.