Nordic nRF9151 Satellite NTN Network
This guide provides the steps to connect the Nordic nRF9151-SMA Development Kit to Skylo satellite Non-Terrestrial Networks (NTN) using a Monogoto SIM.
Quick Navigation
Set up the nRF9151DK
Connect the USB cable to the nRF9151DK
Connect the LTE antenna
Connect the GPS antenna
Insert the Monogoto SIM
Run the latest modem and application firmware
Update the nRF9151DK with the latest modem firmware which supports NTN and use the serial_lte_modem application firmware.
How to update the nRF modem and application firmware
Update modem firmware
Download the latest modem firmware on Nordic's website, under nRF9151 SiP NTN firmware.
Open nRF Connect for Desktop > Programmer.
Upload the .zip file to the Programmer and select Write.
Update application firmware
Download the latest nRF9151 SMA DK application and modem firmware on Nordic's website (e.g. nrf9151dk_mfw-2.0.2_sdk-3.1.0).
Find among the downloads the serial_lte_modem application firmware (e.g. nrf9151dk_serial_lte_modem_2025-XX-XX_XXX )
Upload the .hex file to the Programmer and select Erase & Write.
Open a serial connection with the nRF9151
You can use the Cellular Terminal from the nRF Connect for Desktop, or any program of choice (e.g. PuTTY for Windows, or screen/minicom/miniterm for macOS/Linux).
Set the baud rate to 115200 . To test the connection with the nRF9151 modem enter AT and expect the answer OK.
Check SIM Status
Enable the module
Check SIM status
Expected response: +CPIN: READY
+CPIN: READY means that the SIM is ready and does not require any PIN entry.
Query Device Information
Useful for confirming firmware, hardware and SIM identity.
Request the firmware version
Example response: mfw_nrf9151-ntn_1.0.0-1.alpha
The minimum required modem firmware is mfw_nrf9151-ntn_1.0.0-1.alpha
Request the hardware version
Example response: %HWVERSION:nRF9151 LACA A1A
Request the IMSI
Request the ICCID (Integrated Circuit Card ID), which is the identification number of the SIM
Acquire GPS location
To establish a satellite connection, a location has to be set.
Put the radio in flight mode
Enable GNSS
Activate GPS within the nRF module
Start the GNSS scan
It can easily take up multiple minutes to establish an initial GNSS fix.
Example response:
Save the location as we need it later on.
Shutdown the GPS
Connect the nRF9151 to Skylo
Disable radio
Enable NTN mode (NB-IoT over satellite)
Lock the modem to one or multiple NTN satellite bands
Set GPS location
Format:
Set the location which has just been acquired, e.g.:
Validate if the location was successfully set
Set APN
Subscribe to network status events
CEREG network registration status events
Subscribe to error codes from the network
Subscribe to connection state changes
Enable modem domain event reporting
Enable the radio
Example responses:
CEREG State Codes
0
Not registered, not searching
1
Registered (home network)
2
Not registered, searching
3
Registration denied
4
Unknown / out of coverage
5
Registered & roaming
Radio & Signal Checks
Check the signal quality
Example response: +CESQ: 99,99,255,255,15,53
Request network info
Example response:
Test the Connection by Sending UDP Payload
To send UDP data, send three AT commands:
Create UDP socket
Expected response: #XSOCKET:0,2,17
Connect socket
Replace <ip-address> with the ip address of your UDP server
Set the IP address and port, e.g.:
Expected response: #XCONNECT:1
Send UDP data
Example response: #XSEND:12
Close the UDP socket
Expected response: #XSOCKET:0,"closed"
Switch Between NTN and Public Networks
Use the following commands to switch from NTN to public networks:
Disable radio
Enable public networks
Enable radio
Switch Back to Satellite NTN
Disable radio
Enable NTN
Enable radio
Useful Links
Last updated
Was this helpful?