> ## Documentation Index
> Fetch the complete documentation index at: https://docs.adsumnetworks.com/llms.txt
> Use this file to discover all available pages before exploring further.

# LBG20x: the Adsum NTN Relay for outdoors

> Firmware for the Fanstel LBG20x: your Bluetooth LE devices in; Wi-Fi, LTE-M, NB-IoT and satellite NB-NTN out; Edge AI on board; its own GNSS position; updated over the air. The demo is on every relay, and licences are per relay.

**Bluetooth in. Edge AI on board. Satellite out.** Firmware that listens to your Bluetooth devices, pre-processes with Edge AI, keeps what matters in flash, takes its own GNSS position, and delivers it over Wi-Fi, LTE-M, NB-IoT or satellite NB-NTN, the cheapest uplink that works. Outdoors, fixed or on the move.

<div className="adsum-mast">
  <div><span className="adsum-mast-k">Ways out</span><span className="adsum-mast-v">4 uplinks</span><span className="adsum-mast-n">Wi-Fi where a network is set, then LTE-M, NB-IoT and satellite NB-NTN, cheapest first.</span></div>
  <div><span className="adsum-mast-k">Over satellite</span><span className="adsum-mast-v">128 bytes</span><span className="adsum-mast-n">One datagram carries a status and an alert. Sent and acknowledged on a geostationary service, from the relay's own GNSS position.</span></div>
  <div><span className="adsum-mast-k">Its own position</span><span className="adsum-mast-v">37 s warm fix</span><span className="adsum-mast-n">At 8 m; a cold fix in 60 to 182 s, at 9 to 10 m. Measured on the unit.</span></div>
  <div><span className="adsum-mast-k">Updated over Bluetooth</span><span className="adsum-mast-v">About 4 minutes</span><span className="adsum-mast-n">Both processors, every setting kept: 947 kB in 101 s and 450 kB in 132 s.</span></div>
</div>

<CardGroup cols={2}>
  <Card title="Datasheet (PDF)" icon="file-pdf" href="https://www.adsumnetworks.com/datasheets/LBG20x-NTN-Relay-Firmware-Datasheet.pdf" horizontal>
    Three pages: what it does, how it works, how it is tested, and the specifications.
  </Card>

  <Card title="The first run, step by step" icon="route" href="/supported-hardware/fanstel/lbg20x-first-run" horizontal>
    From a relay out of the box to readings on your own platform, and a command sent back.
  </Card>
</CardGroup>

<div className="adsum-byline">
  <span>Gateway <b>Fanstel LBG20BC02C</b></span>
  <span>Chips <b>nRF54LM20B and nRF9151</b></span>
  <span>Built and verified by <b>Adsum Networks, October 2026</b></span>
</div>

## Who does what

<div className="adsum-roles">
  <div className="adsum-role"><b>Our partner Fanstel · the hardware</b><span>Designs, makes and sells the LBG20x, and publishes its design: Bluetooth 6 with an NPU for edge AI, cellular and satellite with GNSS, Wi-Fi 6 on the BC02C model, a battery charger and a 3-axis motion sensor, in an IP67 outdoor enclosure ready for a solar panel.</span></div>
  <div className="adsum-role"><b>Adsum Networks · the firmware</b><span>Industrial-grade IoT firmware, to use as it is or to customise in hours with Adsum IoT Coder. We then put it through our reliability and security tests, support it, and keep it safe with security updates.</span></div>
  <div className="adsum-role"><b>You · the product</b><span>Your devices, your network, your data platform. Nothing of ours in the path.</span></div>
</div>

## What it is

<div className="my-6 grid gap-6 md:grid-cols-2">
  <div>
    <img className="m-0 w-full rounded-md border border-gray-200 dark:border-gray-800" src="https://mintcdn.com/adsumnetworks/4JvT85hjlMOCn9uE/images/demos/home-lbg20x.jpg?fit=max&auto=format&n=4JvT85hjlMOCn9uE&q=85&s=ebe334c2b10e9f70d993cb7add62fa50" alt="The Fanstel LBG20x gateway in its yellow IP67 enclosure" width="1440" height="810" data-path="images/demos/home-lbg20x.jpg" />

    <p className="m-0 mt-2 text-sm text-gray-500 dark:text-gray-400">The LBG20x as it ships.</p>
  </div>

  <div>
    <img className="m-0 w-full rounded-md border border-gray-200 dark:border-gray-800" src="https://mintcdn.com/adsumnetworks/O_AaTf4fpUXKQfA9/images/demos/lbg20x-open.jpg?fit=max&auto=format&n=O_AaTf4fpUXKQfA9&q=85&s=2adeca995c1f61b54b79125a62d33f05" alt="The LBG20x opened: the mainboard and its M.2 radio card inside the enclosure" width="690" height="532" data-path="images/demos/lbg20x-open.jpg" />

    <p className="m-0 mt-2 text-sm text-gray-500 dark:text-gray-400">Opened: the mainboard and its M.2 radio card.</p>
  </div>
</div>

An outdoor gateway from [Fanstel](https://www.fanstel.com/lbg51e20c): IP67, 107 × 141 × 40 mm with a wall-mount bracket, −40 to +85 °C. It runs from USB-C or an M12 input, takes an optional 18650 cell, and Fanstel describes it as ready for a solar panel. Its LTE antenna is inside or on an SMA connector, and its GNSS antenna on u.FL. Like the BLG20x, it is **two computers on one board**:

* **The Bluetooth half**, a Fanstel BM20 module on Nordic's nRF54LM20B, hears the sensors, decides what is worth keeping, sends over Wi-Fi where the module is fitted and a network is set, and is what you commission over Bluetooth, from Adsum IoT Coder or the commissioning page.
* **The wide-area half**, a Nordic nRF9151, owns the modem: LTE-M, NB-IoT and NB-NTN satellite, and the GNSS receiver that gives the relay its own position.

The two halves run their own firmware and each reports only what it knows itself. The firmware is the BLG20x's, built for this board.

## What the firmware does

<div className="adsum-fig">
  <div className="adsum-pipe">
    <div className="adsum-step"><b>Your sensors</b><span>Anything that advertises over Bluetooth LE.</span></div>
    <div className="adsum-step is-key"><b>The relay</b><span>Admits the devices you name, knows where it is. Counts or quarantines the rest, never silently.</span></div>
    <div className="adsum-step"><b>Wi-Fi, LTE-M, NB-IoT or satellite</b><span>Cheapest first, in the order the deployment allows.</span></div>
    <div className="adsum-step"><b>Your platform</b><span>Your tenant, your devices. Nothing of ours in the path.</span></div>
  </div>

  <p className="adsum-cap">A reading and a command take the same path, in opposite directions.</p>
</div>

* **Commissioned from Adsum IoT Coder or from a browser.** Over Bluetooth either way, every value read back from the unit. The position can be the relay's own GNSS fix, or a phone's or a typed one.
* **A deployment class, set once.** Terrestrial only, satellite only, or both as a ladder. The unit refuses a setting its class cannot carry, at the desk, before it is installed.
* **Only the devices you name.** An expected-devices list admits your sensors. Everything else heard is counted or held in a quarantine you can inspect.
* **Readings to your own platform.** Confirmable CoAP, or MQTT with or without TLS on Wi-Fi and cellular; protobuf or CBOR; each reading with the device's own timestamp.
* **A command back.** A value set on the platform reaches the Bluetooth half on the unit's next exchange.
* **Metered by design.** Wi-Fi first, then the cheapest cell; every send is checked against a monthly allowance, with a separate one for satellite.

## Industrial grade, by design

<div className="adsum-fig">
  <div className="adsum-lanes">
    <div className="adsum-lane"><b>Runs unattended</b><span>Hardware watchdogs, and self-recovery from a hang, a dropped link, a bad configuration or a power cut.</span></div>
    <div className="adsum-lane"><b>Never loses data</b><span>Records wait in flash until your platform acknowledges them. Alarms are never overwritten, and every dropped record is counted.</span></div>
    <div className="adsum-lane"><b>Updated over the air</b><span>Signed updates for both processors, over Bluetooth at the desk or LTE-M and NB-IoT in the field, so a security fix needs no site visit.</span></div>
    <div className="adsum-lane"><b>Edge AI on board</b><span>Data is pre-processed on the relay, beside the radio, so a decision leaves the site and not raw data.</span></div>
    <div className="adsum-lane"><b>Knows where it is</b><span>Its own GNSS fix times the satellite link, and the motion sensor asks for a new one when the relay moves.</span></div>
    <div className="adsum-lane"><b>Secure by design</b><span>Signed boot, secure key storage, authenticated Bluetooth, and only the devices you name admitted. Once claimed, it takes images only with your key.</span></div>
    <div className="adsum-lane"><b>Costs under control</b><span>Wi-Fi first, then the cheapest cell, a data budget counted before every send, and the modem off in between.</span></div>
    <div className="adsum-lane"><b>Tested to prove it</b><span>Reliability and security tests on the real board, GNSS with and without sky. <a href="/supported-hardware/fanstel/lbg20x-specification#tested-to-prove-it">The tests</a>.</span></div>
  </div>
</div>

## Position, and why satellite needs it

**Every record, and where it came from.** A satellite link times itself from the relay's position, so a relay that moves can lose the satellite. This one measures:

* **Measured.** A fix between uplink cycles: 37 s warm, at 8 m; 60 to 182 s cold, at 9 to 10 m.
* **Used by the satellite uplink.** A fix becomes the position the satellite connection is timed from.
* **On request.** Your platform can ask for a new fix whenever it needs one.
* **Movement wakes a fix.** The motion sensor asks for a new position when the relay moves.
* **A fallback.** A position from a phone, or typed in at commissioning, where the sky is hidden.

| Uplink | What leaves the relay | Size |
| :- | :- | :- |
| **Wi-Fi, LTE-M, NB-IoT** | Digests per device, alerts, status and a daily health record | About 1 kB per cycle |
| **Satellite NB-NTN** | Alerts and status only. Everything else waits in flash for a cheaper uplink | One 128 B datagram |

One real datagram, 46 B of transport and 40 B carrying a status and an alert, was sent and acknowledged over a geostationary NB-NTN service on 9 October 2026, on the relay's own GNSS position. More on the link in [satellite IoT: NB-NTN](/satellite-ntn).

## Updated over the air, signed

* **Over Bluetooth, at the desk.** Both processors in about four minutes, from Adsum IoT Coder or the commissioning page, and the unit keeps its settings.
* **Over the mobile network, in the field.** LTE-M or NB-IoT, while the relay keeps working: no site visit.
* **Never over satellite.** An update waits for a cellular uplink, so the satellite allowance is never spent on firmware.
* **Safe by default.** Signed images only, for both processors. A new image is tested on the unit, and rolls back by itself if it does not prove healthy.
* **Yours once claimed.** A relay claimed with your computer's key takes images from no one else.

Measured on the unit, 11 October 2026: both processors over Bluetooth, 947 kB in 101 seconds and 450 kB in 132 seconds.

## From our firmware to your product

<div className="adsum-fig">
  <div className="adsum-ladder">
    <div className="adsum-tier"><div className="adsum-when">Minutes</div><div className="adsum-what"><b>Try it</b><span>The demo comes on every relay from Fanstel: ten devices, no time limit.</span></div></div>
    <div className="adsum-tier"><div className="adsum-when">Under 30 min</div><div className="adsum-what"><b>First relay live</b><span>Commissioned from Adsum IoT Coder or a browser, and sending readings to your own platform.</span></div></div>
    <div className="adsum-tier"><div className="adsum-when">Hours</div><div className="adsum-what"><b>Make it yours</b><span>A new sensor, a rule or a payload, with Adsum IoT Coder, which already knows the board and the firmware.</span></div></div>
    <div className="adsum-tier"><div className="adsum-when">Then</div><div className="adsum-what"><b>Certify your version</b><span>Your build goes through the same reliability and security tests, on the board, and earns its own certificate.</span></div></div>
    <div className="adsum-tier"><div className="adsum-when">Five years</div><div className="adsum-what"><b>Stay secure</b><span>Watched, advised and fixed: security fixes for five years, delivered over the air.</span></div></div>
  </div>
</div>

## BLG20x or LBG20x?

The same firmware, the same uplinks and the same licences. What differs is where the relay goes.

| | BLG20x | LBG20x |
| :- | :- | :- |
| **Where** | Indoors, at a fixed site | Outdoors, fixed or on the move |
| **Position** | Set once at commissioning, from a phone or typed in | Its own GNSS fix: at commissioning, on request, and when it moves |
| **Enclosure** | IP51, 90 × 65 × 28 mm, desk or wall | IP67, 107 × 141 × 40 mm, wall-mount bracket |
| **Operating temperature** | −40 to +80 °C | −40 to +85 °C |
| **Power** | USB-C, with an AC adapter | USB-C or M12; battery and solar next |
| **Records in flash** | 2 MB | 1.4 MB |
| **Cues** | A buzzer | A cue light |
| **Proven over satellite** | A status and two alerts, 13 September 2026 | An alert, on its own GNSS position, 9 October 2026 |
| **Updated over Bluetooth** | Both processors in under six minutes | Both processors in about four minutes |

Both take Wi-Fi on their BC02C models. Fanstel's pages have the models on sale.

## Ways to have it

| | What you get | How |
| :- | :- | :- |
| **Demo firmware** | Both halves, on every relay from Fanstel: ten devices, 10 MB a month over mobile and 10 KB over satellite, no time limit | Free |
| **Production licence** | Our production firmware on one relay: security fixes for five years, a year of new versions (renewed a year at a time), and the evidence pack (certificate, test report, SBOM, advisories and VEX) | [Per relay, see prices](https://www.adsumnetworks.com/licensing/) |
| **Guided first run** | The step-by-step run in Adsum IoT Coder, with the board knowledge behind it | [Free account](/account) |
| **Your own build, certified** | Your device side, built by you in Adsum IoT Coder, certified on the real board | Quoted |
| **Full source** | Change anything, connectivity side included | Ask us |
| **Your device in the catalogue** | Its profile in the next production release, when it serves every buyer | Free, [ask for it](https://www.adsumnetworks.com/request/) |

Buy licences at [www.adsumnetworks.com](https://www.adsumnetworks.com/licensing/). For a quote, the source or your own build, [write to us](https://www.adsumnetworks.com/contact/). We reply within one business day.

## What you need

| | |
| :- | :- |
| **Gateway** | A Fanstel LBG20x, and a SIM on a plan that allows LTE-M or NB-IoT |
| **Tools** | VS Code with Adsum IoT Coder 0.5.1 or later, on a computer with Bluetooth (tested on macOS and Linux) |
| **Bluetooth** | From Adsum IoT Coder: the computer's own Bluetooth. From a browser: Chrome or Edge on a desktop, or Chrome on Android. No browser on iOS supports Web Bluetooth |
| **Probes, rarely** | Only for a unit on an older release: a debug probe for each half, once, with Nordic's `nrfutil` |
| **Platform** | An account on the platform the readings go to. The first run uses [ThingsBoard Cloud](https://thingsboard.cloud/signup), whose free plan is enough to evaluate one relay |
| **Satellite, optional** | The satellite edition, an NB-NTN SIM from a provider that covers your region, and a view of the sky. See [satellite IoT](/satellite-ntn) |

## Next on the LBG20x

* **Battery and charging.** The firmware charges an 18650 cell from USB-C, M12 or a solar panel, and reports its level on your platform.
* **Tamper and orientation,** from the 3-axis motion sensor. Movement already wakes a fix.
* **LoRa,** through the LR2021 on the BC21EE, once its M.2 card is available.

## What the demo firmware does not do

* **No device management.** A demo unit does not appear in a device console and is not updated over the mobile network; that is part of the production firmware. A newer demo release still installs over Bluetooth.
* **No USB data on the mainboard V2.** Its USB-C carries power only, so claiming and updating go over Bluetooth.
* **Limited use.** The demo is for evaluation. The limits are stated in the extension before you install, and the commissioner reads them off the unit.

## Where to buy

Fanstel designs, makes and sells the LBG20 family, including the LBG20BXE, whose Bluetooth module adds a power amplifier, and models with LoRa: [fanstel.com](https://www.fanstel.com/lbg51e20c). Certifications are Fanstel's, model by model. Adsum writes, verifies and licenses the firmware and the knowledge.

<CardGroup cols={2}>
  <Card title="Firmware specification" icon="list-check" href="/supported-hardware/fanstel/lbg20x-specification">
    What each processor does, the GNSS fix, the uplink order, record sizes, updates, recovery and the tests.
  </Card>

  <Card title="The first run, step by step" icon="route" href="/supported-hardware/fanstel/lbg20x-first-run">
    Pair, claim, commission with its own fix, admit a sensor, send readings, send a command back.
  </Card>

  <Card title="Satellite IoT: NB-NTN" icon="satellite" href="/satellite-ntn">
    What NB-NTN is, what it costs, and how the relays use it.
  </Card>

  <Card title="The BLG20x" icon="microchip" href="/supported-hardware/fanstel/blg20x">
    The indoor relay, on the same firmware.
  </Card>
</CardGroup>


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